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Berasategui JA, Žerdoner Čalasan A, Zizka A, Kadereit G. Global distribution, climatic preferences and photosynthesis-related traits of C 4 eudicots and how they differ from those of C 4 grasses. Ecol Evol 2023; 13:e10720. [PMID: 37964791 PMCID: PMC10641307 DOI: 10.1002/ece3.10720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 10/25/2023] [Accepted: 10/30/2023] [Indexed: 11/16/2023] Open
Abstract
C₄ is one of three known photosynthetic processes of carbon fixation in flowering plants. It evolved independently more than 61 times in multiple angiosperm lineages and consists of a series of anatomical and biochemical modifications to the ancestral C3 pathway increasing plant productivity under warm and light-rich conditions. The C4 lineages of eudicots belong to seven orders and 15 families, are phylogenetically less constrained than those of monocots and entail an enormous structural and ecological diversity. Eudicot C4 lineages likely evolved the C4 syndrome along different evolutionary paths. Therefore, a better understanding of this diversity is key to understanding the evolution of this complex trait as a whole. By compiling 1207 recognised C4 eudicots species described in the literature and presenting trait data among these species, we identify global centres of species richness and of high phylogenetic diversity. Furthermore, we discuss climatic preferences in the context of plant functional traits. We identify two hotspots of C4 eudicot diversity: arid regions of Mexico/Southern United States and Australia, which show a similarly high number of different C4 eudicot genera but differ in the number of C4 lineages that evolved in situ. Further eudicot C4 hotspots with many different families and genera are in South Africa, West Africa, Patagonia, Central Asia and the Mediterranean. In general, C4 eudicots are diverse in deserts and xeric shrublands, tropical and subtropical grasslands, savannas and shrublands. We found C4 eudicots to occur in areas with less annual precipitation than C4 grasses which can be explained by frequently associated adaptations to drought stress such as among others succulence and salt tolerance. The data indicate that C4 eudicot lineages utilising the NAD-ME decarboxylating enzyme grow in drier areas than those using the NADP-ME decarboxylating enzyme indicating biochemical restrictions of the later system in higher temperatures. We conclude that in most eudicot lineages, C4 evolved in ancestrally already drought-adapted clades and enabled these to further spread in these habitats and colonise even drier areas.
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Affiliation(s)
- Jessica A. Berasategui
- Prinzessin Therese von Bayern Lehrstuhl für Systematik, Biodiversität & Evolution der PflanzenLudwig‐Maximilians Universität MünchenMünchenGermany
- Institute for Molecular PhysiologyJohannes Gutenberg‐University MainzMainzGermany
| | - Anže Žerdoner Čalasan
- Prinzessin Therese von Bayern Lehrstuhl für Systematik, Biodiversität & Evolution der PflanzenLudwig‐Maximilians Universität MünchenMünchenGermany
| | - Alexander Zizka
- Department of BiologyPhilipps‐University MarburgMarburgGermany
| | - Gudrun Kadereit
- Prinzessin Therese von Bayern Lehrstuhl für Systematik, Biodiversität & Evolution der PflanzenLudwig‐Maximilians Universität MünchenMünchenGermany
- Botanischer Garten München‐Nymphenburg und Botanische Staatssammlung MünchenStaatliche Naturwissenschaftliche Sammlungen BayernsMünchenGermany
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Sharma P, Varga M, Kerezsi G, Kajári B, Halasi-Kovács B, Békefi E, Gaál M, Gyalog G. A dataset on the geographical distribution, bounds, and reed cover of Hungarian fishponds. Data Brief 2023; 49:109354. [PMID: 37448737 PMCID: PMC10336421 DOI: 10.1016/j.dib.2023.109354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 06/14/2023] [Accepted: 06/22/2023] [Indexed: 07/15/2023] Open
Abstract
This paper presents geospatial datasets, figures, and tables illustrating i) the location and total area of fish farms under cultivation; and ii) the spatiotemporal dynamics of reed cover in Hungarian fishponds generated from the published study of Sharma et al., [1]. Preliminary data for fish farm locations were obtained from the Institute of Agricultural Economics (AKI), followed by significant refinement based on high-resolution Google Earth Pro-imagery. The fishpond area dataset was validated against the values reported in annual statistical reports on aquaculture. In order to map reed vegetation freely available Sentinel-2 imagery (between 2017 and 2021) was accessed from the Copernicus Open Access Hub [2] and emergent macrophyte cover was classified using the NDVI-based threshold values [1]. Scientists, policymakers, and fish farmers can all benefit from such geospatial datasets. It could be used to monitor the extent of fishponds in Hungary and to design farm-level reed management plans to optimize the provision of ecological and production services.
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Affiliation(s)
- Priya Sharma
- Research Center for Fisheries and Aquaculture, Institute of Aquaculture and Environmental Safety, Hungarian University of Agriculture and Life Sciences, 35 Anna-liget, Szarvas 5540, Hungary
| | - Mónika Varga
- Institute of Animal Sciences, Hungarian University of Agriculture and Life Sciences, 40 Guba, Kaposvar 7400, Hungary
| | - György Kerezsi
- Research Center for Irrigation and Water Management, Institute of Environmental Sciences, Hungarian University of Agriculture and Life Sciences, Anna-liget 35, Szarvas 5540, Hungary
| | - Balázs Kajári
- Research Center for Irrigation and Water Management, Institute of Environmental Sciences, Hungarian University of Agriculture and Life Sciences, Anna-liget 35, Szarvas 5540, Hungary
| | - Béla Halasi-Kovács
- Research Center for Fisheries and Aquaculture, Institute of Aquaculture and Environmental Safety, Hungarian University of Agriculture and Life Sciences, 35 Anna-liget, Szarvas 5540, Hungary
| | - Emese Békefi
- Research Center for Fisheries and Aquaculture, Institute of Aquaculture and Environmental Safety, Hungarian University of Agriculture and Life Sciences, 35 Anna-liget, Szarvas 5540, Hungary
| | - Márta Gaál
- Institute of Agricultural Economics (AKI), 3-5 Zsil u., Budapest 1093, Hungary
| | - Gergő Gyalog
- Research Center for Fisheries and Aquaculture, Institute of Aquaculture and Environmental Safety, Hungarian University of Agriculture and Life Sciences, 35 Anna-liget, Szarvas 5540, Hungary
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3
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Chen Z, Wang W, Cescatti A, Forzieri G. Climate-driven vegetation greening further reduces water availability in drylands. GLOBAL CHANGE BIOLOGY 2023; 29:1628-1647. [PMID: 36524280 DOI: 10.1111/gcb.16561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 12/09/2022] [Indexed: 05/28/2023]
Abstract
Climate change alters surface water availability (WA; precipitation minus evapotranspiration, P - ET) and consequently impacts agricultural production and societal water needs, leading to increasing concerns on the sustainability of water use. Although the direct effects of climate change on WA have long been recognized and assessed, indirect climate effects occurring through adjustments in terrestrial vegetation are more subtle and not yet fully quantified. To address this knowledge gap, here we investigate the interplay between climate-induced changes in leaf area index (LAI) and ET and quantify its ultimate effect on WA during the period 1982-2016 at the global scale, using an ensemble of data-driven products and land surface models. We show that ~44% of the global vegetated land has experienced a significant increase in growing season-averaged LAI and climate change explains 33.5% of this greening signal. Such climate-induced greening has enhanced ET of 0.051 ± 0.067 mm year-2 (mean ± SD), further amplifying the ongoing increase in ET directly driven by variations in climatic factors over 36.8% of the globe, and thus exacerbating the decline in WA prominently in drylands. These findings highlight the indirect impact of positive feedbacks in the land-climate system on the decline of WA, and call for an in-depth evaluation of these phenomena in the design of local mitigation and adaptation plans.
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Affiliation(s)
- Zefeng Chen
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, China
- College of Hydrology and Water Resources, Hohai University, Nanjing, China
| | - Weiguang Wang
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, China
- College of Hydrology and Water Resources, Hohai University, Nanjing, China
- Key Laboratory of Water Big Data Technology of Ministry of Water Resources, Hohai University, Nanjing, China
| | | | - Giovanni Forzieri
- Department of Civil and Environmental Engineering, University of Florence, Florence, Italy
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Jahan R, McDonald IR. Diversity of Methylobacterium species associated with New Zealand native plants. FEMS Microbiol Lett 2023; 370:fnad124. [PMID: 37985695 PMCID: PMC10699869 DOI: 10.1093/femsle/fnad124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 09/26/2023] [Accepted: 11/17/2023] [Indexed: 11/22/2023] Open
Abstract
Methylobacterium species are abundant colonizers of the phyllosphere due to the availability of methanol, a waste product of pectin metabolism during plant cell division. The phyllosphere is an extreme environment, with a landscape that is heterogeneous and continuously changing as the plant grows and is exposed to high levels of ultraviolet irradiation. Geographically, New Zealand (NZ) has been isolated for over a million years, has a biologically diverse flora, and is considered a biodiversity hotspot, with most native plants being endemic. We therefore hypothesize that the phyllosphere of NZ native plants harbor diverse groups of Methylobacterium species. Leaf imprinting using methanol-supplemented agar medium was used to isolate bacteria, and diversity was determined using ARDRA and 16S rRNA gene sequencing. Methylobacterium species were successfully isolated from the phyllosphere of 18 of the 20 native NZ plant species in this study, and six different species were identified: M. marchantiae, M. mesophilicum, M. adhaesivum, M. komagatae, M. extorquens, and M. phyllosphaerae. Other α, β, and γ-Proteobacteria, Actinomycetes, Bacteroidetes, and Firmicutes were also isolated, highlighting the presence of other potentially novel methanol utilizers within this ecosystem. This study identified that Methylobacterium are abundant members of the NZ phyllosphere, with species diversity and composition dependent on plant species.
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Affiliation(s)
- Rowshan Jahan
- Te Aka Mātuatua—School of Science, Te Whare Wānanga o Waikato—University of Waikato, Private Bag 3105, Hamilton 3240, Aotearoa, New Zealand
| | - Ian R McDonald
- Te Aka Mātuatua—School of Science, Te Whare Wānanga o Waikato—University of Waikato, Private Bag 3105, Hamilton 3240, Aotearoa, New Zealand
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Vinod N, Slot M, McGregor IR, Ordway EM, Smith MN, Taylor TC, Sack L, Buckley TN, Anderson-Teixeira KJ. Thermal sensitivity across forest vertical profiles: patterns, mechanisms, and ecological implications. THE NEW PHYTOLOGIST 2023; 237:22-47. [PMID: 36239086 DOI: 10.1111/nph.18539] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 07/31/2022] [Indexed: 06/16/2023]
Abstract
Rising temperatures are influencing forests on many scales, with potentially strong variation vertically across forest strata. Using published research and new analyses, we evaluate how microclimate and leaf temperatures, traits, and gas exchange vary vertically in forests, shaping tree, and ecosystem ecology. In closed-canopy forests, upper canopy leaves are exposed to the highest solar radiation and evaporative demand, which can elevate leaf temperature (Tleaf ), particularly when transpirational cooling is curtailed by limited stomatal conductance. However, foliar traits also vary across height or light gradients, partially mitigating and protecting against the elevation of upper canopy Tleaf . Leaf metabolism generally increases with height across the vertical gradient, yet differences in thermal sensitivity across the gradient appear modest. Scaling from leaves to trees, canopy trees have higher absolute metabolic capacity and growth, yet are more vulnerable to drought and damaging Tleaf than their smaller counterparts, particularly under climate change. By contrast, understory trees experience fewer extreme high Tleaf 's but have fewer cooling mechanisms and thus may be strongly impacted by warming under some conditions, particularly when exposed to a harsher microenvironment through canopy disturbance. As the climate changes, integrating the patterns and mechanisms reviewed here into models will be critical to forecasting forest-climate feedback.
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Affiliation(s)
- Nidhi Vinod
- Conservation Ecology Center, Smithsonian's National Zoo & Conservation Biology Institute, Front Royal, VA, 22630, USA
- Department of Ecology and Evolutionary Biology, UCLA, Los Angeles, CA, 90039, USA
| | - Martijn Slot
- Smithsonian Tropical Research Institute, Apartado Postal 0843-03092, Panama City, Panama
| | - Ian R McGregor
- Center for Geospatial Analytics, North Carolina State University, Raleigh, NC, 27607, USA
| | - Elsa M Ordway
- Department of Ecology and Evolutionary Biology, UCLA, Los Angeles, CA, 90039, USA
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Marielle N Smith
- Department of Forestry, Michigan State University, East Lansing, MI, 48824, USA
- School of Natural Sciences, College of Environmental Sciences and Engineering, Bangor University, Bangor, LL57 2DG, UK
| | - Tyeen C Taylor
- Department of Civil & Environmental Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Lawren Sack
- Department of Ecology and Evolutionary Biology, UCLA, Los Angeles, CA, 90039, USA
| | - Thomas N Buckley
- Department of Plant Sciences, University of California, Davis, CA, 95616, USA
| | - Kristina J Anderson-Teixeira
- Conservation Ecology Center, Smithsonian's National Zoo & Conservation Biology Institute, Front Royal, VA, 22630, USA
- Smithsonian Tropical Research Institute, Apartado Postal 0843-03092, Panama City, Panama
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Zuo J, Tang X, Zhang H, Zu M, Zhang X, Yuan Y. Analysis of niche shift and potential suitable distributions of Dendrobium under the impact of global climate change. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:11978-11993. [PMID: 36103069 DOI: 10.1007/s11356-022-22920-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Accepted: 09/03/2022] [Indexed: 06/15/2023]
Abstract
Dendrobium is a valuable traditional Chinese herb that contains active ingredients such as polysaccharides and alkaloids that have anti-aging, antioxidant, and immunomodulating effects. The appropriate distribution range of Dendrobium should be predicted from the perspective of ecological niche theory in order to preserve and utilize medicinal plant resources. In this study, Dendrobium nobile, Dendrobium officinale, and Dendrobium moniliforme were selected to predict the potential suitable distributions and ecological niche shifts. A comparison of 19 environmental variables of the three Dendrobium species revealed three climatic factors that differed significantly when the species were compared two at a time. The principal component analysis was carried out in order to screen seven climatic factors for ecological niche shift analysis. All three Dendrobium species were found to have a very similar ecological niche, but with a relatively small range of variability regarding certain climatic factors. Finally, the current and future suitable areas for these three Dendrobium species in China were predicted using the MaxEnt model and ArcGIS using the two representative concentration pathways (RCP 2.6 and 8.5). Overall, the analysis of the climatic factors' comparisons, niche shift, and current and future suitable areas of these three Dendrobium species provides a basis for medicinal plant resource conservation and utilization, and our methods could be applied to the study of other similar valuable medicinal plants.
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Affiliation(s)
- Jiajia Zuo
- Jiangsu Key Laboratory of Crop Genetics and Physiology, College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, 225009, People's Republic of China
| | - Xinggang Tang
- Co-Innovation Center for Sustainable Forestry in Southern China, Jiangsu Province Key Laboratory of Soil and Water Conservation and Ecological Restoration, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
| | - Hanyue Zhang
- Jiangsu Key Laboratory of Crop Genetics and Physiology, College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, 225009, People's Republic of China
| | - Mengting Zu
- Jiangsu Key Laboratory of Crop Genetics and Physiology, College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, 225009, People's Republic of China
| | - Xihe Zhang
- Department of Tourism and Art, Guangling College, Yangzhou University, Yangzhou, 225009, People's Republic of China
| | - Yingdan Yuan
- Jiangsu Key Laboratory of Crop Genetics and Physiology, College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, 225009, People's Republic of China.
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Three Decades of Gross Primary Production (GPP) in China: Variations, Trends, Attributions, and Prediction Inferred from Multiple Datasets and Time Series Modeling. REMOTE SENSING 2022. [DOI: 10.3390/rs14112564] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The accurate estimation of gross primary production (GPP) is crucial to understanding plant carbon sequestration and grasping the quality of the ecological environment. Nevertheless, due to the inconsistencies of current GPP products, the variations, trends and short-term predictions of GPP have not been sufficiently well studied. In this study, we explore the spatiotemporal variability and trends of GPP and its associated climatic and anthropogenic factors in China from 1982 to 2015, mainly based on the optimum light use efficiency (LUEopt) product. We also employ an autoregressive integrated moving average (ARIMA) model to forecast the monthly GPP for a one-year lead time. The results show that GPP experienced an upward trend of 2.268 g C/m2 per year during the studied period, that is, an increasing rate of 3.9% per decade since 1982. However, these trend changes revealed distinct heterogeneity across space and time. The positive trends were mainly distributed in the Yellow River and Huaihe River out of the nine major river basins in China. We found that the dynamics of GPP were concurrently affected by climate factors and human activities. While air temperature and leaf area index (LAI) played dominant roles at a national level, the effects of precipitation, downward shortwave radiation (SRAD), carbon dioxide (CO2) and aerosol optical depth (AOD) exhibited discrepancies in terms of degree and scope. The ARIMA model achieved satisfactory prediction performance in most areas, though the accuracy was influenced by both data values and data quality. The model can potentially be generalized for other biophysical parameters with distinct seasonality. Our findings are further verified and corroborated by four widely used GPP products, demonstrating a good consistency of GPP trends and prediction. Our analysis provides a robust framework for characterizing long-term GPP dynamics that shed light on the improved assessment of the environmental quality of terrestrial ecosystems.
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Guidelines for Publicly Archiving Terrestrial Model Data to Enhance Usability, Intercomparison, and Synthesis. DATA SCIENCE JOURNAL 2022. [DOI: 10.5334/dsj-2022-003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
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9
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Wei Y, Lan G, Wu Z, Chen B, Quan F, Li M, Sun S, Du H. Phyllosphere fungal communities of rubber trees exhibited biogeographical patterns, but not bacteria. Environ Microbiol 2022; 24:3777-3790. [PMID: 35001480 DOI: 10.1111/1462-2920.15894] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/29/2021] [Accepted: 01/01/2022] [Indexed: 11/28/2022]
Abstract
Phyllosphere microbiomes play an essential role in maintaining host health and productivity. Still, the diversity patterns and the drivers for the phyllosphere microbial community of the tropical cash crop Rubber tree (Hevea brasiliensis) - are poorly understood. We sampled the phyllosphere of field-grown rubber trees in South China. We examined the phyllosphere bacterial and fungal composition, diversity and main drivers of these microbes using the Illumina® sequencing and assembly. Fungal communities were distinctly different in different climatic regions (i.e. Xishuangbanna and Hainan Island) and climatic factors, especially mean annual temperature, and they were the main driving factors of foliar fungal communities, indicating fungal communities showed a geographical pattern. Significant differences of phyllosphere bacterial communities were detected in different habitats (i.e. endophytic and epiphytic). Most of the differences in taxa composition came from Firmicutes spp., which have been assigned as nitrogen-fixing bacteria. Since these bacteria cannot penetrate the cuticle like fungi, the abundant epiphytic Firmicutes spp. may supplement the deficiency of nitrogen acquisition. And the main factor influencing endophytic bacteria were internal factors, such as total nitrogen, total phosphorus and water content of leaves. External factors (i.e. climate) were the main driving force for epiphytic bacteria community assembly. Our work provides empirical evidence that the assembly of phyllosphere bacterial and fungal differed, which creates a precedent for preventing and controlling rubber tree diseases and pests and rubber tree yield improvement.
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Affiliation(s)
- Yaqing Wei
- College of Ecology and Environment, Hainan University, Haikou, 570228, China.,Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road, Haikou, Hainan, 571737, China.,Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou, Hainan, 571737, China
| | - Guoyu Lan
- Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road, Haikou, Hainan, 571737, China.,Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou, Hainan, 571737, China
| | - Zhixiang Wu
- Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road, Haikou, Hainan, 571737, China.,Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou, Hainan, 571737, China
| | - Bangqian Chen
- Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road, Haikou, Hainan, 571737, China.,Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou, Hainan, 571737, China
| | - Fei Quan
- Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road, Haikou, Hainan, 571737, China.,Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou, Hainan, 571737, China
| | - Mingmei Li
- Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road, Haikou, Hainan, 571737, China.,Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou, Hainan, 571737, China
| | - Shuqing Sun
- Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road, Haikou, Hainan, 571737, China.,Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou, Hainan, 571737, China
| | - Haonan Du
- Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road, Haikou, Hainan, 571737, China.,Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou, Hainan, 571737, China
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Smith RJ, Singarayer JS, Mayle FE. Response of Amazonian forests to mid-Holocene drought: A model-data comparison. GLOBAL CHANGE BIOLOGY 2022; 28:201-226. [PMID: 34651394 DOI: 10.1111/gcb.15929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 09/22/2021] [Accepted: 09/25/2021] [Indexed: 06/13/2023]
Abstract
There is a major concern for the fate of Amazonia over the coming century in the face of anthropogenic climate change. A key area of uncertainty is the scale of rainforest dieback to be expected under a future, drier climate. In this study, we use the middle Holocene (ca. 6000 years before present) as an approximate analogue for a drier future, given that palaeoclimate data show much of Amazonia was significantly drier than present at this time. Here, we use an ensemble of climate and vegetation models to explore the sensitivity of Amazonian biomes to mid-Holocene climate change. For this, we employ three dynamic vegetation models (JULES, IBIS, and SDGVM) forced by the bias-corrected mid-Holocene climate simulations from seven models that participated in the Palaeoclimate Modelling Intercomparison Project 3 (PMIP3). These model outputs are compared with a multi-proxy palaeoecological dataset to gain a better understanding of where in Amazonia we have most confidence in the mid-Holocene vegetation simulations. A robust feature of all simulations and palaeodata is that the central Amazonian rainforest biome is unaffected by mid-Holocene drought. Greater divergence in mid-Holocene simulations exists in ecotonal eastern and southern Amazonia. Vegetation models driven with climate models that simulate a drier mid-Holocene (100-150 mm per year decrease) better capture the observed (palaeodata) tropical forest dieback in these areas. Based on the relationship between simulated rainfall decrease and vegetation change, we find indications that in southern Amazonia the rate of tropical forest dieback was ~125,000 km2 per 100 mm rainfall decrease in the mid-Holocene. This provides a baseline sensitivity of tropical forests to drought for this region (without human-driven changes to greenhouse gases, fire, and deforestation). We highlight the need for more palaeoecological and palaeoclimate data across lowland Amazonia to constrain model responses.
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Affiliation(s)
- Richard J Smith
- Department of Geography and Environmental Science, School of Archaeology, Geography and Environmental Science (SAGES), University of Reading, Whiteknights, Reading, UK
| | - Joy S Singarayer
- Department of Meteorology, University of Reading, Whiteknights, Reading, UK
| | - Francis E Mayle
- Department of Geography and Environmental Science, School of Archaeology, Geography and Environmental Science (SAGES), University of Reading, Whiteknights, Reading, UK
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Yan K, Han W, Zhu Q, Li C, Dong Z, Wang Y. Leaf surface microtopography shaping the bacterial community in the phyllosphere: evidence from 11 tree species. Microbiol Res 2021; 254:126897. [PMID: 34710835 DOI: 10.1016/j.micres.2021.126897] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 09/27/2021] [Accepted: 10/13/2021] [Indexed: 10/20/2022]
Abstract
Phyllosphere bacteria are an important component of environmental microbial communities and are closely related to plant health and ecosystem stability. However, the relationships between the inhabitation and assembly of phyllosphere bacteria and leaf microtopography are still obscure. In this study, the phyllosphere bacterial communities and leaf microtopographic features (vein density, stomatal length, and density) of eleven tree species were fully examined. Both the absolute abundance and diversity of phyllosphere bacterial communities were significantly different among the tree species, and leaf vein density dominated the variation. TITAN analysis showed that leaf vein density also played more important roles in regulating the relative abundance of bacteria than stomatal features, and 6 phyla and 62 genera of phyllosphere bacteria showed significant positive responses to leaf vein density. Moreover, LEfSe analysis showed that the leaves with higher vein density had more bacterial biomarkers. Leaf vein density also changed the co-occurrence pattern of phyllosphere bacteria, and the co-occurrence network demonstrated more negative correlations and more nodes on the leaves with larger leaf vein density, indicating that higher densities of leaf veins improved the stability of the phyllosphere bacterial community. Phylogenetic analysis showed that deterministic processes (especially homogeneous selection) dominated the assembly process of phyllosphere bacterial communities. The leaf vein density increased the degree of bacterial clustering at the phylogenetic level. Therefore, the inhabitation and assembly of the phyllosphere bacterial community are related to leaf microtopography, which provides deeper insight into the interaction between plants and bacteria.
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Affiliation(s)
- Kun Yan
- Taishan Forest Ecosystem Research Station of State Forestry Administration, College of Forestry, Shandong Agricultural University, Tai'an, 271018, PR China
| | - Wenhao Han
- Taishan Forest Ecosystem Research Station of State Forestry Administration, College of Forestry, Shandong Agricultural University, Tai'an, 271018, PR China
| | - Qiliang Zhu
- Taishan Forest Ecosystem Research Station of State Forestry Administration, College of Forestry, Shandong Agricultural University, Tai'an, 271018, PR China
| | - Chuanrong Li
- Taishan Forest Ecosystem Research Station of State Forestry Administration, College of Forestry, Shandong Agricultural University, Tai'an, 271018, PR China
| | - Zhi Dong
- Taishan Forest Ecosystem Research Station of State Forestry Administration, College of Forestry, Shandong Agricultural University, Tai'an, 271018, PR China
| | - Yanping Wang
- Taishan Forest Ecosystem Research Station of State Forestry Administration, College of Forestry, Shandong Agricultural University, Tai'an, 271018, PR China.
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12
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Ambient Air Pollution Shapes Bacterial and Fungal Ivy Leaf Communities. Microorganisms 2021; 9:microorganisms9102088. [PMID: 34683409 PMCID: PMC8540654 DOI: 10.3390/microorganisms9102088] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 09/27/2021] [Accepted: 10/01/2021] [Indexed: 01/04/2023] Open
Abstract
Ambient air pollution exerts deleterious effects on our environment. Continuously exposed to the atmosphere, diverse communities of microorganisms thrive on leaf surfaces, the phylloplane. The composition of these communities is dynamic, responding to many environmental factors including ambient air pollution. In this field study, over a 2 year period, we sampled Hedera helix (ivy) leaves at six locations exposed to different ambient air pollution conditions. Daily, we monitored ambient black carbon (BC), PM2.5, PM10, nitrogen dioxide, and ozone concentrations and found that ambient air pollution led to a 2–7-fold BC increase on leaves, the phylloplane BC load. Our results further indicated that the phylloplane BC load correlates with the diversity of bacterial and fungal leaf communities, impacting diversity more than seasonal effects. The bacterial genera Novosphingobium, Hymenobacter, and Methylorubrum, and the fungal genus Ampelomyces were indicators for communities exposed to the highest phylloplane BC load. Parallel to this, we present one fungal and two bacterial phylloplane strains isolated from an air-polluted environment able to degrade benzene, toluene, and/or xylene, including a genomics-based description of the degradation pathways involved. The findings of this study suggest that ambient air pollution shapes microbial leaf communities, by affecting diversity and supporting members able to degrade airborne pollutants.
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13
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Palmer JL, Hilton S, Picot E, Bending GD, Schäfer H. Tree phyllospheres are a habitat for diverse populations of CO-oxidizing bacteria. Environ Microbiol 2021; 23:6309-6327. [PMID: 34523801 DOI: 10.1111/1462-2920.15770] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 07/21/2021] [Accepted: 09/08/2021] [Indexed: 11/28/2022]
Abstract
Carbon monoxide (CO) is both a ubiquitous atmospheric trace gas and an air pollutant. While aerobic CO-degrading microorganisms in soils and oceans are estimated to remove ~370 Tg of CO per year, the presence of CO-degrading microorganisms in above-ground habitats, such as the phyllosphere, and their potential role in CO cycling remains unknown. CO-degradation by leaf washes of two common British trees, Ilex aquifolium and Crataegus monogyna, demonstrated CO uptake in all samples investigated. Based on the analyses of taxonomic and functional genes, diverse communities of candidate CO-oxidizing taxa were identified, including members of Rhizobiales and Burkholderiales which were abundant in the phyllosphere at the time of sampling. Based on predicted genomes of phyllosphere community members, an estimated 21% of phyllosphere bacteria contained CoxL, the large subunit of CO-dehydrogenase. In support of this, data mining of publicly available phyllosphere metagenomes for genes encoding CO-dehydrogenase subunits demonstrated that, on average, 25% of phyllosphere bacteria contained CO-dehydrogenase gene homologues. A CO-oxidizing Phyllobacteriaceae strain was also isolated from phyllosphere samples which contains genes encoding both CO-dehydrogenase as well as a ribulose-1,5-bisphosphate carboxylase-oxygenase. These results suggest that the phyllosphere supports diverse and potentially abundant CO-oxidizing bacteria, which are a potential sink for atmospheric CO.
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Affiliation(s)
- Jess L Palmer
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Sally Hilton
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Emma Picot
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Gary D Bending
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Hendrik Schäfer
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
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14
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Walker AP, Johnson AL, Rogers A, Anderson J, Bridges RA, Fisher RA, Lu D, Ricciuto DM, Serbin SP, Ye M. Multi-hypothesis comparison of Farquhar and Collatz photosynthesis models reveals the unexpected influence of empirical assumptions at leaf and global scales. GLOBAL CHANGE BIOLOGY 2021; 27:804-822. [PMID: 33037690 PMCID: PMC7894311 DOI: 10.1111/gcb.15366] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 09/01/2020] [Indexed: 05/19/2023]
Abstract
Mechanistic photosynthesis models are at the heart of terrestrial biosphere models (TBMs) simulating the daily, monthly, annual and decadal rhythms of carbon assimilation (A). These models are founded on robust mathematical hypotheses that describe how A responds to changes in light and atmospheric CO2 concentration. Two predominant photosynthesis models are in common usage: Farquhar (FvCB) and Collatz (CBGB). However, a detailed quantitative comparison of these two models has never been undertaken. In this study, we unify the FvCB and CBGB models to a common parameter set and use novel multi-hypothesis methods (that account for both hypothesis and parameter variability) for process-level sensitivity analysis. These models represent three key biological processes: carboxylation, electron transport, triose phosphate use (TPU) and an additional model process: limiting-rate selection. Each of the four processes comprises 1-3 alternative hypotheses giving 12 possible individual models with a total of 14 parameters. To broaden inference, TBM simulations were run and novel, high-resolution photosynthesis measurements were made. We show that parameters associated with carboxylation are the most influential parameters but also reveal the surprising and marked dominance of the limiting-rate selection process (accounting for 57% of the variation in A vs. 22% for carboxylation). The limiting-rate selection assumption proposed by CBGB smooths the transition between limiting rates and always reduces A below the minimum of all potentially limiting rates, by up to 25%, effectively imposing a fourth limitation on A. Evaluation of the CBGB smoothing function in three TBMs demonstrated a reduction in global A by 4%-10%, equivalent to 50%-160% of current annual fossil fuel emissions. This analysis reveals a surprising and previously unquantified influence of a process that has been integral to many TBMs for decades, highlighting the value of multi-hypothesis methods.
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Affiliation(s)
- Anthony P. Walker
- Environmental Sciences Division and Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTNUSA
| | - Abbey L. Johnson
- Environmental Sciences Division and Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTNUSA
| | - Alistair Rogers
- Environmental & Climates Sciences DepartmentBrookhaven National LaboratoryUptonNYUSA
| | - Jeremiah Anderson
- Environmental & Climates Sciences DepartmentBrookhaven National LaboratoryUptonNYUSA
| | - Robert A. Bridges
- Cyber & Applied Data Analytics DivisionOak Ridge National LaboratoryOak RidgeTNUSA
| | - Rosie A. Fisher
- National Center for Atmospheric ResearchBoulderCOUSA
- Centre Européen de Recherche et de Formation Avancée en Calcul Scientifique (CERFACS)ToulouseFrance
| | - Dan Lu
- Computational Sciences & Engineering DivisionOak Ridge National LaboratoryOak RidgeTNUSA
| | - Daniel M. Ricciuto
- Environmental Sciences Division and Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTNUSA
| | - Shawn P. Serbin
- Environmental & Climates Sciences DepartmentBrookhaven National LaboratoryUptonNYUSA
| | - Ming Ye
- Department of Earth, Ocean, and Atmospheric ScienceFlorida State UniversityTallahasseeFLUSA
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15
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Li SF, Valdes PJ, Farnsworth A, Davies-Barnard T, Su T, Lunt DJ, Spicer RA, Liu J, Deng WYD, Huang J, Tang H, Ridgwell A, Chen LL, Zhou ZK. Orographic evolution of northern Tibet shaped vegetation and plant diversity in eastern Asia. SCIENCE ADVANCES 2021; 7:eabc7741. [PMID: 33571113 PMCID: PMC7840128 DOI: 10.1126/sciadv.abc7741] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 12/04/2020] [Indexed: 05/09/2023]
Abstract
The growth of the Tibetan Plateau throughout the past 66 million years has profoundly affected the Asian climate, but how this unparalleled orogenesis might have driven vegetation and plant diversity changes in eastern Asia is poorly understood. We approach this question by integrating modeling results and fossil data. We show that growth of north and northeastern Tibet affects vegetation and, crucially, plant diversity in eastern Asia by altering the monsoon system. This northern Tibetan orographic change induces a precipitation increase, especially in the dry (winter) season, resulting in a transition from deciduous broadleaf vegetation to evergreen broadleaf vegetation and plant diversity increases across southeastern Asia. Further quantifying the complexity of Tibetan orographic change is critical for understanding the finer details of Asian vegetation and plant diversity evolution.
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Affiliation(s)
- Shu-Feng Li
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China.
- Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Mengla 666303, China
- School of Geographical Sciences, University of Bristol, Bristol, UK
| | - Paul J Valdes
- School of Geographical Sciences, University of Bristol, Bristol, UK
| | - Alex Farnsworth
- School of Geographical Sciences, University of Bristol, Bristol, UK
| | - T Davies-Barnard
- School of Geographical Sciences, University of Bristol, Bristol, UK
- College of Engineering, Maths, and Physical Sciences, University of Exeter, Exeter, UK
- Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Tao Su
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China
- Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Mengla 666303, China
| | - Daniel J Lunt
- School of Geographical Sciences, University of Bristol, Bristol, UK
| | - Robert A Spicer
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China
- School of Environment, Earth and Ecosystem Sciences, The Open University, Milton Keynes, MK7 6AA, UK
| | - Jia Liu
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China
| | - Wei-Yu-Dong Deng
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jian Huang
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China
| | - He Tang
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Andy Ridgwell
- School of Geographical Sciences, University of Bristol, Bristol, UK
- Earth and Planetary Sciences, University of California, Riverside, CA 92521, USA
| | - Lin-Lin Chen
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhe-Kun Zhou
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China.
- Key Laboratory of Biogeography and Biodiversity, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China
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16
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Singh E, Schenk PM, Carvalhais LC. Sample Preparation for Culture-Independent Profiling and Isolation of Phyllosphere Bacteria to Identify Potential Biopesticides. Methods Mol Biol 2021; 2232:193-208. [PMID: 33161549 DOI: 10.1007/978-1-0716-1040-4_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Studying the plant phyllosphere to understand inhibition patterns to the growth of fungal foliar pathogens by using the Arabidopsis thaliana pathosystem offers unique opportunities for evaluating strategies for plant protection against foliar diseases. The wide array of bacteria inhabiting the phylloplane of plants has been researched to a much lesser extent compared to the bacteria in the rhizosphere. This difference is especially evident as bacteria derived from the aerial section of plants are rarely used in formulations of foliage sprays against pathogens and pests. In this chapter we outline easy and reliable methods for sample preparation to profile phyllosphere bacteria using high throughput amplicon sequencing and isolate/characterize potentially beneficial phyllosphere bacteria from Arabidopsis thaliana that inhibit in vitro the growth of foliar pathogens such as Alternaria brassicicola. The use of the described methods for profiling and screening phyllosphere bacteria may provide tangible progress on the discovery of new potential biological control agents against agriculturally important pathogens.
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Affiliation(s)
- Eugenie Singh
- Plant-Microbe Interactions Laboratory, School of Agriculture and Food Sciences, The University of Queensland, St Lucia, QLD, Australia
| | - Peer M Schenk
- Plant-Microbe Interactions Laboratory, School of Agriculture and Food Sciences, The University of Queensland, St Lucia, QLD, Australia.
| | - Lilia C Carvalhais
- Centre for Horticultural Science, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, QLD, Australia
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17
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Kusstatscher P, Wicaksono WA, Bergna A, Cernava T, Bergau N, Tissier A, Hause B, Berg G. Trichomes form genotype-specific microbial hotspots in the phyllosphere of tomato. ENVIRONMENTAL MICROBIOME 2020; 15:17. [PMID: 33902724 PMCID: PMC8067393 DOI: 10.1186/s40793-020-00364-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 08/29/2020] [Indexed: 05/03/2023]
Abstract
BACKGROUND The plant phyllosphere is a well-studied habitat characterized by low nutrient availability and high community dynamics. In contrast, plant trichomes, known for their production of a large number of metabolites, are a yet unexplored habitat for microbes. We analyzed the phyllosphere as well as trichomes of two tomato genotypes (Solanum lycopersicum LA4024, S. habrochaites LA1777) by targeting bacterial 16S rRNA gene fragments. RESULTS Leaves, leaves without trichomes, and trichomes alone harbored similar abundances of bacteria (108-109 16S rRNA gene copy numbers per gram of sample). In contrast, bacterial diversity was found significantly increased in trichome samples (Shannon index: 4.4 vs. 2.5). Moreover, the community composition was significantly different when assessed with beta diversity analysis and corresponding statistical tests. At the bacterial class level, Alphaproteobacteria (23.6%) were significantly increased, whereas Bacilli (8.6%) were decreased in trichomes. The bacterial family Sphingomonadacea (8.4%) was identified as the most prominent, trichome-specific feature; Burkholderiaceae and Actinobacteriaceae showed similar patterns. Moreover, Sphingomonas was identified as a central element in the core microbiome of trichome samples, while distinct low-abundant bacterial families including Hymenobacteraceae and Alicyclobacillaceae were exclusively found in trichome samples. Niche preferences were statistically significant for both genotypes and genotype-specific enrichments were further observed. CONCLUSION Our results provide first evidence of a highly specific trichome microbiome in tomato and show the importance of micro-niches for the structure of bacterial communities on leaves. These findings provide further clues for breeding, plant pathology and protection as well as so far unexplored natural pathogen defense strategies.
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Affiliation(s)
- Peter Kusstatscher
- Institute of Environmental Biotechnology, Graz University of Technology, Graz, Austria
| | - Wisnu Adi Wicaksono
- Institute of Environmental Biotechnology, Graz University of Technology, Graz, Austria
| | - Alessandro Bergna
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), Graz, Austria
| | - Tomislav Cernava
- Institute of Environmental Biotechnology, Graz University of Technology, Graz, Austria
| | - Nick Bergau
- Department of Cell and Metabolic Biology, Leibniz Institute of Plant Biochemistry, Halle, Germany
| | - Alain Tissier
- Department of Cell and Metabolic Biology, Leibniz Institute of Plant Biochemistry, Halle, Germany
| | - Bettina Hause
- Department of Cell and Metabolic Biology, Leibniz Institute of Plant Biochemistry, Halle, Germany
| | - Gabriele Berg
- Institute of Environmental Biotechnology, Graz University of Technology, Graz, Austria
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18
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Yan ZZ, Chen QL, Zhang YJ, He JZ, Hu HW. Industrial development as a key factor explaining variances in soil and grass phyllosphere microbiomes in urban green spaces. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 261:114201. [PMID: 32109819 DOI: 10.1016/j.envpol.2020.114201] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 02/10/2020] [Accepted: 02/15/2020] [Indexed: 06/10/2023]
Abstract
Microbiota in urban green spaces underpin ecosystem services that are essential to environmental health and human wellbeing. However, the factors shaping the microbial communities in urban green spaces, especially those associated with turf grass phyllosphere, remain poorly understood. The lack of this knowledge greatly limits our ability to assess ecological, social and recreational benefits of urban green spaces in the context of global urbanization. In this study, we used amplicon sequencing to characterize soil and grass phyllosphere bacterial communities in 40 urban green spaces and three minimally disturbed national parks in Victoria, Australia. The results indicated that urbanization might have shown different impacts on soil and grass phyllosphere microbial communities. The bacterial diversity in soil but not in grass phyllosphere was significantly higher in urban green spaces than in national parks. Principal coordinate analysis revealed significant differences in the overall patterns of bacterial community composition between urban green spaces and national parks for both soil and grass phyllosphere. Industrial development, as represented by the number of industries in the region, was identified as a key driver shaping the bacterial community profiles in urban green spaces. Variation partitioning analysis suggested that industrial factors together with their interaction with other factors explained 20% and 28% of the variances in soil and grass phyllosphere bacterial communities, respectively. The findings highlight the importance of industrial development in driving the spatial patterns of urban microbiomes, and have important implication for the management of microbiomes in urban green spaces.
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Affiliation(s)
- Zhen-Zhen Yan
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC, 3010, Australia
| | - Qing-Lin Chen
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC, 3010, Australia
| | - Yu-Jing Zhang
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC, 3010, Australia
| | - Ji-Zheng He
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC, 3010, Australia
| | - Hang-Wei Hu
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC, 3010, Australia.
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19
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Zervas A, Zeng Y, Madsen AM, Hansen LH. Genomics of Aerobic Photoheterotrophs in Wheat Phyllosphere Reveals Divergent Evolutionary Patterns of Photosynthetic Genes in Methylobacterium spp. Genome Biol Evol 2020; 11:2895-2908. [PMID: 31626703 PMCID: PMC6798729 DOI: 10.1093/gbe/evz204] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/11/2019] [Indexed: 01/02/2023] Open
Abstract
Phyllosphere is a habitat to a variety of viruses, bacteria, fungi, and other microorganisms, which play a fundamental role in maintaining the health of plants and mediating the interaction between plants and ambient environments. A recent addition to this catalogue of microbial diversity was the aerobic anoxygenic phototrophs (AAPs), a group of widespread bacteria that absorb light through bacteriochlorophyll α (BChl a) to produce energy without fixing carbon or producing molecular oxygen. However, culture representatives of AAPs from phyllosphere and their genome information are lacking, limiting our capability to assess their potential ecological roles in this unique niche. In this study, we investigated the presence of AAPs in the phyllosphere of a winter wheat (Triticum aestivum L.) in Denmark by employing bacterial colony based infrared imaging and MALDI-TOF mass spectrometry (MS) techniques. A total of ∼4,480 colonies were screened for the presence of cellular BChl a, resulting in 129 AAP isolates that were further clustered into 21 groups based on MALDI-TOF MS profiling, representatives of which were sequenced using the Illumina NextSeq and Oxford Nanopore MinION platforms. Seventeen draft and four complete genomes of AAPs were assembled belonging in Methylobacterium, Rhizobium, Roseomonas, and a novel Alsobacter. We observed a diverging pattern in the evolutionary rates of photosynthesis genes among the highly homogenous AAP strains of Methylobacterium (Alphaproteobacteria), highlighting an ongoing genomic innovation at the gene cluster level.
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Affiliation(s)
- Athanasios Zervas
- Section of Environmental Microbiology and Biotechnology, Department of Environmental Science, Aarhus University, Roskilde, Denmark
| | - Yonghui Zeng
- Section of Environmental Microbiology and Biotechnology, Department of Environmental Science, Aarhus University, Roskilde, Denmark.,Aarhus Institute of Advanced Studies, Aarhus University, Denmark
| | - Anne Mette Madsen
- National Research Centre for the Working Environment, Copenhagen, Denmark
| | - Lars H Hansen
- Section of Environmental Microbiology and Biotechnology, Department of Environmental Science, Aarhus University, Roskilde, Denmark.,Environmental Microbial Genomics Group, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
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20
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Carlström CI, Field CM, Bortfeld-Miller M, Müller B, Sunagawa S, Vorholt JA. Synthetic microbiota reveal priority effects and keystone strains in the Arabidopsis phyllosphere. Nat Ecol Evol 2019; 3:1445-1454. [PMID: 31558832 PMCID: PMC6774761 DOI: 10.1038/s41559-019-0994-z] [Citation(s) in RCA: 146] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 08/21/2019] [Indexed: 12/12/2022]
Abstract
Multicellular organisms including plants are colonised by microorganisms, some of which are beneficial to growth and health. The assembly rules for establishing the plant microbiota are not well understood, and neither is the extent to which their members interact. We conducted drop-out and late introduction experiments by inoculating Arabidopsis thaliana with synthetic communities from a resource of 62 native bacterial strains to test how arrival order shapes community structure. As a read-out we tracked the relative abundance of all strains in the phyllosphere of individual plants. Our results showed that community assembly is historically contingent and subject to priority effects. Missing strains could, to various degrees, invade an already established microbiota, which was itself resistant and remained largely unaffected by latecomers. Additionally, our results indicate that individual Proteobacteria (Sphingomonas, Rhizobium) and Actinobacteria (Microbacterium, Rhodococcus) strains have the greatest potential to affect community structure as keystone species.
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Affiliation(s)
| | | | | | - Barbara Müller
- Institute of Microbiology, ETH Zurich, Zurich, Switzerland
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21
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Potential Transient Response of Terrestrial Vegetation and Carbon in Northern North America from Climate Change. CLIMATE 2019. [DOI: 10.3390/cli7090113] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Terrestrial ecosystems and their vegetation are linked to climate. With the potential of accelerated climate change from anthropogenic forcing, there is a need to further evaluate the transient response of ecosystems, their vegetation, and their influence on the carbon balance, to this change. The equilibrium response of ecosystems to climate change has been estimated in previous studies in global domains. However, research on the transient response of terrestrial vegetation to climate change is often limited to domains at the sub-continent scale. Estimation of the transient response of vegetation requires the use of mechanistic models to predict the consequences of competition, dispersal, landscape heterogeneity, disturbance, and other factors, where it becomes computationally prohibitive at scales larger than sub-continental. Here, we used a pseudo-spatial ecosystem model with a vegetation migration sub-model that reduced computational intensity and predicted the transient response of vegetation and carbon to climate change in northern North America. The ecosystem model was first run with a current climatology at half-degree resolution for 1000 years to establish current vegetation and carbon distribution. From that distribution, climate was changed to a future climatology and the ecosystem model run for an additional 2000 simulation years. A model experimental design with different combinations of vegetation dispersal rates, dispersal modes, and disturbance rates produced 18 potential change scenarios. Results indicated that potential redistribution of terrestrial vegetation from climate change was strongly impacted by dispersal rates, moderately affected by disturbance rates, and marginally impacted by dispersal mode. For carbon, the sensitivities were opposite. A potential transient net carbon sink greater than that predicted by the equilibrium response was estimated on time scales of decades–centuries, but diminished over longer time scales. Continued research should further explore the interactions between competition, dispersal, and disturbance, particularly in regards to vegetation redistribution.
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22
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Zhou SYD, Zhu D, Giles M, Yang XR, Daniell T, Neilson R, Zhu YG. Phyllosphere of staple crops under pig manure fertilization, a reservoir of antibiotic resistance genes. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 252:227-235. [PMID: 31153027 DOI: 10.1016/j.envpol.2019.05.098] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 05/18/2019] [Accepted: 05/19/2019] [Indexed: 05/11/2023]
Abstract
In China, the common use of antibiotics in agriculture is recognized as a potential public health risk through the increasing use of livestock derived manure as a means of fertilization. By doing so this may increase the transfer of antibiotic resistance genes (ARGs) from animals, to soils and plants. In this study two staple crops (rice and wheat) were investigated for ARG enrichment under differing fertilization regimes. Here, we applied 4 treatments, no fertilizer, mineral fertilizer, clean (reduced antibiotic practice) and dirty (current antibiotic practice) pig manure, to soil microcosms planted with either rice or wheat, to investigate fertilization effects on the abundance of ARGs in the respective phyllospheres. For both rice and wheat, samples were collected after two separate fertilization periods. In total, 162 unique ARGs and 5 mobile genetic elements (MGEs) were detected from all rice and wheat samples. The addition of both clean and dirty manure, enhanced ARG abundance significantly when compared to no fertilizer treatments (P < 0.001), though clean manure enriched ARGs to a lesser extent than dirty manure, in all rice and wheat samples (P < 0.001). The classes of ARGs recorded were different between crops, with wheat samples having a higher ARG diversity than rice. These results revealed that staple crops in China such as rice and wheat may be a reservoir for ARGs when clean and dirty pig manure is used for fertilization.
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Affiliation(s)
- Shu-Yi-Dan Zhou
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, 361021, China; University of the Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China
| | - Dong Zhu
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, 361021, China; University of the Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China
| | - Madeline Giles
- Ecological Sciences, The James Hutton Institute, Dundee, DD2 5DA, Scotland, UK
| | - Xiao-Ru Yang
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, 361021, China
| | - Tim Daniell
- Department of Animal and Plant Sciences, The University of Sheffield, Sheffield, S10 2TN, UK; Ecological Sciences, The James Hutton Institute, Dundee, DD2 5DA, Scotland, UK
| | - Roy Neilson
- Ecological Sciences, The James Hutton Institute, Dundee, DD2 5DA, Scotland, UK
| | - Yong-Guan Zhu
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, 361021, China; University of the Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China; State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
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23
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Zakharova L, Meyer K, Seifan M. Trait-based modelling in ecology: A review of two decades of research. Ecol Modell 2019. [DOI: 10.1016/j.ecolmodel.2019.05.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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24
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Brownstein NC, Louis TA, O'Hagan A, Pendergast J. The Role of Expert Judgment in Statistical Inference and Evidence-Based Decision-Making. AM STAT 2019; 73:56-68. [PMID: 31057338 PMCID: PMC6474725 DOI: 10.1080/00031305.2018.1529623] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 09/14/2018] [Accepted: 09/15/2018] [Indexed: 11/21/2022]
Abstract
This article resulted from our participation in the session on the “role of expert opinion and judgment in statistical inference” at the October 2017 ASA Symposium on Statistical Inference. We present a strong, unified statement on roles of expert judgment in statistics with processes for obtaining input, whether from a Bayesian or frequentist perspective. Topics include the role of subjectivity in the cycle of scientific inference and decisions, followed by a clinical trial and a greenhouse gas emissions case study that illustrate the role of judgments and the importance of basing them on objective information and a comprehensive uncertainty assessment. We close with a call for increased proactivity and involvement of statisticians in study conceptualization, design, conduct, analysis, and communication.
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Affiliation(s)
- Naomi C Brownstein
- Department of Biostatistics and Bioinformatics, Moffitt Cancer Center, Tampa, FL.,Department of Oncologic Sciences, University of South Florida, Tampa, FL.,Department of Behavioral Sciences and Social Medicine, Florida State University, Tallahassee, FL
| | - Thomas A Louis
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Anthony O'Hagan
- School of Mathematics and Statistics, The University of Sheffield, Sheffield, UK
| | - Jane Pendergast
- Department of Biostatistics and Bioinformatics, Duke University, Durham, NC
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25
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Liang J, Xia J, Shi Z, Jiang L, Ma S, Lu X, Mauritz M, Natali SM, Pegoraro E, Penton CR, Plaza C, Salmon VG, Celis G, Cole JR, Konstantinidis KT, Tiedje JM, Zhou J, Schuur EAG, Luo Y. Biotic responses buffer warming-induced soil organic carbon loss in Arctic tundra. GLOBAL CHANGE BIOLOGY 2018; 24:4946-4959. [PMID: 29802797 DOI: 10.1111/gcb.14325] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 05/10/2018] [Indexed: 05/06/2023]
Abstract
Climate warming can result in both abiotic (e.g., permafrost thaw) and biotic (e.g., microbial functional genes) changes in Arctic tundra. Recent research has incorporated dynamic permafrost thaw in Earth system models (ESMs) and indicates that Arctic tundra could be a significant future carbon (C) source due to the enhanced decomposition of thawed deep soil C. However, warming-induced biotic changes may influence biologically related parameters and the consequent projections in ESMs. How model parameters associated with biotic responses will change under warming and to what extent these changes affect projected C budgets have not been carefully examined. In this study, we synthesized six data sets over 5 years from a soil warming experiment at the Eight Mile Lake, Alaska, into the Terrestrial ECOsystem (TECO) model with a probabilistic inversion approach. The TECO model used multiple soil layers to track dynamics of thawed soil under different treatments. Our results show that warming increased light use efficiency of vegetation photosynthesis but decreased baseline (i.e., environment-corrected) turnover rates of SOC in both the fast and slow pools in comparison with those under control. Moreover, the parameter changes generally amplified over time, suggesting processes of gradual physiological acclimation and functional gene shifts of both plants and microbes. The TECO model predicted that field warming from 2009 to 2013 resulted in cumulative C losses of 224 or 87 g/m2 , respectively, without or with changes in those parameters. Thus, warming-induced parameter changes reduced predicted soil C loss by 61%. Our study suggests that it is critical to incorporate biotic changes in ESMs to improve the model performance in predicting C dynamics in permafrost regions.
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Affiliation(s)
- Junyi Liang
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee
| | - Jiangyang Xia
- Tiantong National Station of Forest Ecosystem, Research Center for Global Change and Ecological Forecasting, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
- Institute of Eco-Chongming (IEC), Shanghai, China
| | - Zheng Shi
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma
| | - Lifen Jiang
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma
- Center for Ecosystem Science and Society and Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona
| | - Shuang Ma
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma
- Center for Ecosystem Science and Society and Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona
| | - Xingjie Lu
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma
- Center for Ecosystem Science and Society and Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona
| | - Marguerite Mauritz
- Center for Ecosystem Science and Society and Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona
| | | | - Elaine Pegoraro
- Center for Ecosystem Science and Society and Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona
| | - Christopher Ryan Penton
- College of Integrative Sciences and Arts, Arizona State University, Mesa, Arizona
- Center for Fundamental and Applied Microbiomics, Biodesign Institute, Arizona State University, Tempe, Arizona
| | - César Plaza
- Center for Ecosystem Science and Society and Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona
- Departamento de Biología y Geología, Física y Química Inorgánica, Escuela Superior de Ciencias Experimentales y Tecnología, Universidad Rey Juan Carlos, Móstoles, Spain
- Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Verity G Salmon
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee
| | - Gerardo Celis
- Center for Ecosystem Science and Society and Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona
| | - James R Cole
- Department of Plant, Soil and Microbial Sciences, Center for Microbial Ecology, Michigan State University, East Lansing, Michigan
| | - Konstantinos T Konstantinidis
- School of Civil and Environmental Engineering and School of Biology, Georgia Institute of Technology, Atlanta, Georgia
| | - James M Tiedje
- Department of Plant, Soil and Microbial Sciences, Center for Microbial Ecology, Michigan State University, East Lansing, Michigan
| | - Jizhong Zhou
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma
- Institute for Environmental Genomics, University of Oklahoma, Norman, Oklahoma
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China
- Earth and Environmental Sciences, Lawrence Berkeley National Laboratory, Berkeley, California
| | - Edward A G Schuur
- Center for Ecosystem Science and Society and Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona
| | - Yiqi Luo
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma
- Center for Ecosystem Science and Society and Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona
- Department of Earth System Science, Tsinghua University, Beijing, China
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26
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Mahnert A, Ortega RA, Berg C, Grube M, Berg G. Leaves of Indoor Ornamentals Are Biodiversity and Functional Hotspots for Fungi. Front Microbiol 2018; 9:2343. [PMID: 30327646 PMCID: PMC6174238 DOI: 10.3389/fmicb.2018.02343] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 09/12/2018] [Indexed: 12/18/2022] Open
Abstract
Leaf-inhabiting fungi are an important, but often overlooked component of molecular biodiversity studies. To understand their diversity and function in relation to plant species and climate, the phyllospheres of 14 phylogenetically diverse ornamental plant species were analyzed under different controlled greenhouse conditions. We found unexpectedly high fungal diversity (H' = 2.8-6.5), OTU numbers (449-1050) and abundances (103-106 CFU cm-2 leaf surface) associated with all plants studied indoors. Despite experimental limitations, the composition of fungal communities were inclined toward a plant species-dependent pattern compared to the ambient climatic variables. Most detected fungi were patho- and saprotrophs showing a yeast-like growth morphology and were associated to the groups of endophytes and potential plant pathogens in a plant species-specific manner. A representative strain collection showed that 1/3 of the tested fungi (mainly Penicillium, Cladosporium, and Cryptococcus spp.) were able to inhibit mycelial growth and 2/3 inhibit sporulation of the plant pathogen Botrytis cinerea by the production of antifungal volatile organic compounds (VOCs) completely. This study indicates that plant leaves harbor a stable phyllosphere fungal diversity in diverse microclimates and enrich distinctive functional guilds.
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Affiliation(s)
- Alexander Mahnert
- Institute of Environmental Biotechnology, Graz University of Technology, Graz, Austria
| | - Rocel Amor Ortega
- Institute of Environmental Biotechnology, Graz University of Technology, Graz, Austria
- Department of Biology, College of Science, University of the Philippines Baguio, Baguio, Philippines
| | - Christian Berg
- Institute of Plant Sciences, Karl-Franzens-University, Graz, Austria
| | - Martin Grube
- Institute of Plant Sciences, Karl-Franzens-University, Graz, Austria
| | - Gabriele Berg
- Institute of Environmental Biotechnology, Graz University of Technology, Graz, Austria
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27
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Fox DL, Pau S, Taylor L, Strömberg CAE, Osborne CP, Bradshaw C, Conn S, Beerling DJ, Still CJ. Climatic Controls on C4 Grassland Distributions During the Neogene: A Model-Data Comparison. Front Ecol Evol 2018. [DOI: 10.3389/fevo.2018.00147] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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28
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Liu Z, Ballantyne AP, Poulter B, Anderegg WRL, Li W, Bastos A, Ciais P. Precipitation thresholds regulate net carbon exchange at the continental scale. Nat Commun 2018; 9:3596. [PMID: 30185789 PMCID: PMC6125429 DOI: 10.1038/s41467-018-05948-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 08/03/2018] [Indexed: 11/16/2022] Open
Abstract
Understanding the sensitivity of ecosystem production and respiration to climate change is critical for predicting terrestrial carbon dynamics. Here we show that the primary control on the inter-annual variability of net ecosystem carbon exchange switches from production to respiration at a precipitation threshold between 750 and 950 mm yr−1 in the contiguous United States. This precipitation threshold is evident across multiple datasets and scales of observation indicating that it is a robust result and provides a new scaling relationship between climate and carbon dynamics. However, this empirical precipitation threshold is not captured by dynamic global vegetation models, which tend to overestimate the sensitivity of production and underestimate the sensitivity of respiration to water availability in more mesic regions. Our results suggest that the short-term carbon balance of ecosystems may be more sensitive to respiration losses than previously thought and that model simulations may underestimate the positive carbon–climate feedbacks associated with respiration. The sensitivity of terrestrial net ecosystem carbon exchange (NEE) to climate remains a major source of uncertainty. Here, the authors identify a precipitation threshold of between 750-950 mm yr−1 for the contiguous United States, beyond which NEE is regulated by respiration rather than production.
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Affiliation(s)
- Zhihua Liu
- Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, MT, 59812, USA. .,CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China.
| | - Ashley P Ballantyne
- Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, MT, 59812, USA
| | - Benjamin Poulter
- Biospheric Sciences Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, 20770, USA
| | | | - Wei Li
- Laboratoire des Sciences du Climat et de l'Environnement/Institut Pierre Simon Laplace, Commissariat à l'Énergie Atomique et aux Énergies Alternatives-CNRS-Université de Versailles Saint-Quentin, Université Paris-Saclay, F-91191, Gif-sur-Yvette, France
| | - Ana Bastos
- Laboratoire des Sciences du Climat et de l'Environnement/Institut Pierre Simon Laplace, Commissariat à l'Énergie Atomique et aux Énergies Alternatives-CNRS-Université de Versailles Saint-Quentin, Université Paris-Saclay, F-91191, Gif-sur-Yvette, France.,Department of Geography, Ludwig-Maximilians-Universität München, Luisenstr. 37, 80333, Munich, Germany
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l'Environnement/Institut Pierre Simon Laplace, Commissariat à l'Énergie Atomique et aux Énergies Alternatives-CNRS-Université de Versailles Saint-Quentin, Université Paris-Saclay, F-91191, Gif-sur-Yvette, France
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29
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Assessing the characteristics of net primary production due to future climate change and CO 2 under RCP4.5 in China. ECOLOGICAL COMPLEXITY 2018. [DOI: 10.1016/j.ecocom.2018.04.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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30
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Mills BJW, Batterman SA, Field KJ. Nutrient acquisition by symbiotic fungi governs Palaeozoic climate transition. Philos Trans R Soc Lond B Biol Sci 2018; 373:20160503. [PMID: 29254967 PMCID: PMC5745338 DOI: 10.1098/rstb.2016.0503] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/27/2017] [Indexed: 11/12/2022] Open
Abstract
Fossil evidence from the Rhynie chert indicates that early land plants, which evolved in a high-CO2 atmosphere during the Palaeozoic Era, hosted diverse fungal symbionts. It is hypothesized that the rise of early non-vascular land plants, and the later evolution of roots and vasculature, drove the long-term shift towards a high-oxygen, low CO2 climate that eventually permitted the evolution of mammals and, ultimately, humans. However, very little is known about the productivity of the early terrestrial biosphere, which depended on the acquisition of the limiting nutrient phosphorus via fungal symbiosis. Recent laboratory experiments have shown that plant-fungal symbiotic function is specific to fungal identity, with carbon-for-phosphorus exchange being either enhanced or suppressed under superambient CO2 By incorporating these experimental findings into a biogeochemical model, we show that the differences in these symbiotic nutrient acquisition strategies could greatly alter the plant-driven changes to climate, allowing drawdown of CO2 to glacial levels, and altering the nature of the rise of oxygen. We conclude that an accurate depiction of plant-fungal symbiotic systems, informed by high-CO2 experiments, is key to resolving the question of how the first terrestrial ecosystems altered our planet.This article is part of a discussion meeting issue 'The Rhynie cherts: our earliest terrestrial ecosystem revisited'.
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Affiliation(s)
| | - Sarah A Batterman
- School of Geography, University of Leeds, Leeds LS2 9JT, UK
- Priestley International Centre for Climate, University of Leeds, Leeds LS2 9JT, UK
- Smithsonian Tropical Research Institute, Ancon, Panama
| | - Katie J Field
- Centre for Plant Sciences, School of Biology, University of Leeds, Leeds LS2 9JT, UK
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31
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Fisher RA, Koven CD, Anderegg WRL, Christoffersen BO, Dietze MC, Farrior CE, Holm JA, Hurtt GC, Knox RG, Lawrence PJ, Lichstein JW, Longo M, Matheny AM, Medvigy D, Muller-Landau HC, Powell TL, Serbin SP, Sato H, Shuman JK, Smith B, Trugman AT, Viskari T, Verbeeck H, Weng E, Xu C, Xu X, Zhang T, Moorcroft PR. Vegetation demographics in Earth System Models: A review of progress and priorities. GLOBAL CHANGE BIOLOGY 2018; 24:35-54. [PMID: 28921829 DOI: 10.1111/gcb.13910] [Citation(s) in RCA: 183] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 08/12/2017] [Accepted: 08/17/2017] [Indexed: 05/24/2023]
Abstract
Numerous current efforts seek to improve the representation of ecosystem ecology and vegetation demographic processes within Earth System Models (ESMs). These developments are widely viewed as an important step in developing greater realism in predictions of future ecosystem states and fluxes. Increased realism, however, leads to increased model complexity, with new features raising a suite of ecological questions that require empirical constraints. Here, we review the developments that permit the representation of plant demographics in ESMs, and identify issues raised by these developments that highlight important gaps in ecological understanding. These issues inevitably translate into uncertainty in model projections but also allow models to be applied to new processes and questions concerning the dynamics of real-world ecosystems. We argue that stronger and more innovative connections to data, across the range of scales considered, are required to address these gaps in understanding. The development of first-generation land surface models as a unifying framework for ecophysiological understanding stimulated much research into plant physiological traits and gas exchange. Constraining predictions at ecologically relevant spatial and temporal scales will require a similar investment of effort and intensified inter-disciplinary communication.
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Affiliation(s)
- Rosie A Fisher
- National Center for Atmospheric Research, Boulder, CO, USA
| | | | | | | | - Michael C Dietze
- Department of Earth and Environment, Boston University, Boston, MA, USA
| | - Caroline E Farrior
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | | | - George C Hurtt
- Department of Geographical Sciences, University of Maryland, College Park, MD, USA
| | - Ryan G Knox
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | | | | | - Marcos Longo
- Embrapa Agricultural Informatics, Campinas, Brazil
| | - Ashley M Matheny
- Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, Austin, TX, USA
| | - David Medvigy
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | | | | | - Shawn P Serbin
- Environmental and Climate Sciences Department, Brookhaven National Laboratory, Upton, NY, USA
| | - Hisashi Sato
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokohama, Japan
| | | | - Benjamin Smith
- Department of Physical Geography and Ecosystem Science, Lund University, Lund, Sweden
| | - Anna T Trugman
- Program in Atmospheric and Oceanic Sciences, Princeton University, Princeton, NJ, USA
| | - Toni Viskari
- Smithsonian Tropical Research Institute, Panamá, Panamá
| | - Hans Verbeeck
- Department of Applied Ecology and Environmental Biology, Faculty of Bioscience Engineering, Ghent University, Gent, Belgium
| | - Ensheng Weng
- Center for Climate Systems Research, Columbia University, New York, NY, USA
| | - Chonggang Xu
- Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Xiangtao Xu
- Department of Geosciences, Princeton University, Princeton, NJ, USA
| | - Tao Zhang
- Department of Biology, University of Florida, Gainesville, FL, USA
| | - Paul R Moorcroft
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
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32
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Huntingford C, Atkin OK, Martinez-de la Torre A, Mercado LM, Heskel MA, Harper AB, Bloomfield KJ, O'Sullivan OS, Reich PB, Wythers KR, Butler EE, Chen M, Griffin KL, Meir P, Tjoelker MG, Turnbull MH, Sitch S, Wiltshire A, Malhi Y. Implications of improved representations of plant respiration in a changing climate. Nat Commun 2017; 8:1602. [PMID: 29150610 PMCID: PMC5693865 DOI: 10.1038/s41467-017-01774-z] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 10/13/2017] [Indexed: 11/09/2022] Open
Abstract
Land-atmosphere exchanges influence atmospheric CO2. Emphasis has been on describing photosynthetic CO2 uptake, but less on respiration losses. New global datasets describe upper canopy dark respiration (R d) and temperature dependencies. This allows characterisation of baseline R d, instantaneous temperature responses and longer-term thermal acclimation effects. Here we show the global implications of these parameterisations with a global gridded land model. This model aggregates R d to whole-plant respiration R p, driven with meteorological forcings spanning uncertainty across climate change models. For pre-industrial estimates, new baseline R d increases R p and especially in the tropics. Compared to new baseline, revised instantaneous response decreases R p for mid-latitudes, while acclimation lowers this for the tropics with increases elsewhere. Under global warming, new R d estimates amplify modelled respiration increases, although partially lowered by acclimation. Future measurements will refine how R d aggregates to whole-plant respiration. Our analysis suggests R p could be around 30% higher than existing estimates.
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Affiliation(s)
- Chris Huntingford
- Centre for Ecology and Hydrology, Wallingford, Oxfordshire, OX10 8BB, UK.
| | - Owen K Atkin
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 134, Canberra, ACT, 2601, Australia.,ARC Centre of Excellence in Plant Energy Biology, Research School of Biology, The Australian National University, Building 134, Canberra, ACT, 2601, Australia
| | | | - Lina M Mercado
- Centre for Ecology and Hydrology, Wallingford, Oxfordshire, OX10 8BB, UK.,College of Life and Environmental Sciences, Amory Building, University of Exeter, Rennes Drive, Exeter, EX4 4RJ, UK
| | - Mary A Heskel
- The Ecosystems Center, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA, 02543, USA
| | - Anna B Harper
- College of Engineering, Mathematics and Physical Sciences, Laver Building, University of Exeter, North Park Road, Exeter, EX4 4QF, UK
| | - Keith J Bloomfield
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 134, Canberra, ACT, 2601, Australia
| | - Odhran S O'Sullivan
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 134, Canberra, ACT, 2601, Australia
| | - Peter B Reich
- Department of Forest Resources, University of Minnesota, 1530 Cleveland Avenue North, St Paul, MN, 55108, USA.,Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW 2751, Australia
| | - Kirk R Wythers
- Department of Forest Resources, University of Minnesota, 1530 Cleveland Avenue North, St Paul, MN, 55108, USA
| | - Ethan E Butler
- Department of Forest Resources, University of Minnesota, 1530 Cleveland Avenue North, St Paul, MN, 55108, USA
| | - Ming Chen
- Department of Forest Resources, University of Minnesota, 1530 Cleveland Avenue North, St Paul, MN, 55108, USA
| | - Kevin L Griffin
- Department of Earth and Environmental Sciences, Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10964-8000, USA
| | - Patrick Meir
- Division of Plant Sciences, Research School of Biology, The Australian National University, Building 134, Canberra, ACT, 2601, Australia.,School of Geosciences, University of Edinburgh, Edinburgh, EH9 3FF, UK
| | - Mark G Tjoelker
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW 2751, Australia
| | - Matthew H Turnbull
- Centre for Integrative Ecology, School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Stephen Sitch
- College of Life and Environmental Sciences, Amory Building, University of Exeter, Rennes Drive, Exeter, EX4 4RJ, UK
| | | | - Yadvinder Malhi
- School of Geography and the Environment, Oxford University Centre for the Environment, University of Oxford, South Parks Road, Oxford, OX1 3QY, UK
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33
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De Kauwe MG, Medlyn BE, Walker AP, Zaehle S, Asao S, Guenet B, Harper AB, Hickler T, Jain AK, Luo Y, Lu X, Luus K, Parton WJ, Shu S, Wang YP, Werner C, Xia J, Pendall E, Morgan JA, Ryan EM, Carrillo Y, Dijkstra FA, Zelikova TJ, Norby RJ. Challenging terrestrial biosphere models with data from the long-term multifactor Prairie Heating and CO 2 Enrichment experiment. GLOBAL CHANGE BIOLOGY 2017; 23:3623-3645. [PMID: 28145053 DOI: 10.1111/gcb.13643] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 01/15/2017] [Indexed: 06/06/2023]
Abstract
Multifactor experiments are often advocated as important for advancing terrestrial biosphere models (TBMs), yet to date, such models have only been tested against single-factor experiments. We applied 10 TBMs to the multifactor Prairie Heating and CO2 Enrichment (PHACE) experiment in Wyoming, USA. Our goals were to investigate how multifactor experiments can be used to constrain models and to identify a road map for model improvement. We found models performed poorly in ambient conditions; there was a wide spread in simulated above-ground net primary productivity (range: 31-390 g C m-2 yr-1 ). Comparison with data highlighted model failures particularly with respect to carbon allocation, phenology, and the impact of water stress on phenology. Performance against the observations from single-factors treatments was also relatively poor. In addition, similar responses were predicted for different reasons across models: there were large differences among models in sensitivity to water stress and, among the N cycle models, N availability during the experiment. Models were also unable to capture observed treatment effects on phenology: they overestimated the effect of warming on leaf onset and did not allow CO2 -induced water savings to extend the growing season length. Observed interactive (CO2 × warming) treatment effects were subtle and contingent on water stress, phenology, and species composition. As the models did not correctly represent these processes under ambient and single-factor conditions, little extra information was gained by comparing model predictions against interactive responses. We outline a series of key areas in which this and future experiments could be used to improve model predictions of grassland responses to global change.
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Affiliation(s)
- Martin G De Kauwe
- Department of Biological Science, Macquarie University, North Ryde, NSW, 2109, Australia
| | - Belinda E Medlyn
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Anthony P Walker
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN, 37831, USA
| | - Sönke Zaehle
- Biogeochemical Integration Department, Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, 07745, Jena, Germany
| | - Shinichi Asao
- Natural Resource Ecology Laboratory, Colorado State University, Fort Collins, CO, 80523-1499, USA
| | - Bertrand Guenet
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, F-91191, Gif-sur-Yvette, France
| | - Anna B Harper
- College of Engineering, Mathematics, and Physical Sciences, University of Exeter, Exeter, EX4 4QF, UK
| | - Thomas Hickler
- Senckenberg Biodiversity and Climate Research Centre (BiK-F), Senckenberganlage 25, 60325, Frankfurt, Germany
- Department of Physical Geography, Geosciences, Goethe-University, Altenhöferallee 1, 60438, Frankfurt, Germany
| | - Atul K Jain
- Department of Atmospheric Sciences, University of Illinois, 105 South Gregory Street, Urbana, IL, 61801-3070, USA
| | - Yiqi Luo
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, 73019, USA
| | - Xingjie Lu
- CSIRO Oceans and Atmosphere, Private Bag #1, Aspendale, Vic., 3195, Australia
| | - Kristina Luus
- Biogeochemical Integration Department, Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, 07745, Jena, Germany
| | - William J Parton
- Natural Resource Ecology Laboratory, Colorado State University, Fort Collins, CO, 80523-1499, USA
| | - Shijie Shu
- Department of Atmospheric Sciences, University of Illinois, 105 South Gregory Street, Urbana, IL, 61801-3070, USA
| | - Ying-Ping Wang
- CSIRO Oceans and Atmosphere, Private Bag #1, Aspendale, Vic., 3195, Australia
| | - Christian Werner
- Senckenberg Biodiversity and Climate Research Centre (BiK-F), Senckenberganlage 25, 60325, Frankfurt, Germany
| | - Jianyang Xia
- Tiantong National Forest Ecosystem Observation and Research Station, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, 200062, China
| | - Elise Pendall
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Jack A Morgan
- Rangeland Resources Research Unit, Agricultural Research Service, United States Department of Agriculture, Fort Collins, CO, 80526, USA
| | - Edmund M Ryan
- Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YW, UK
| | - Yolima Carrillo
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Feike A Dijkstra
- Centre for Carbon, Water and Food, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Tamara J Zelikova
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
| | - Richard J Norby
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN, 37831, USA
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Walker AP, Quaife T, van Bodegom PM, De Kauwe MG, Keenan TF, Joiner J, Lomas MR, MacBean N, Xu C, Yang X, Woodward FI. The impact of alternative trait-scaling hypotheses for the maximum photosynthetic carboxylation rate (V cmax ) on global gross primary production. THE NEW PHYTOLOGIST 2017. [PMID: 28643848 DOI: 10.1111/nph.14623] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The maximum photosynthetic carboxylation rate (Vcmax ) is an influential plant trait that has multiple scaling hypotheses, which is a source of uncertainty in predictive understanding of global gross primary production (GPP). Four trait-scaling hypotheses (plant functional type, nutrient limitation, environmental filtering, and plant plasticity) with nine specific implementations were used to predict global Vcmax distributions and their impact on global GPP in the Sheffield Dynamic Global Vegetation Model (SDGVM). Global GPP varied from 108.1 to 128.2 PgC yr-1 , 65% of the range of a recent model intercomparison of global GPP. The variation in GPP propagated through to a 27% coefficient of variation in net biome productivity (NBP). All hypotheses produced global GPP that was highly correlated (r = 0.85-0.91) with three proxies of global GPP. Plant functional type-based nutrient limitation, underpinned by a core SDGVM hypothesis that plant nitrogen (N) status is inversely related to increasing costs of N acquisition with increasing soil carbon, adequately reproduced global GPP distributions. Further improvement could be achieved with accurate representation of water sensitivity and agriculture in SDGVM. Mismatch between environmental filtering (the most data-driven hypothesis) and GPP suggested that greater effort is needed understand Vcmax variation in the field, particularly in northern latitudes.
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Affiliation(s)
- Anthony P Walker
- Oak Ridge National Laboratory, Environmental Sciences Division and Climate Change Science Institute, Oak Ridge, TN, 37830-6301, USA
- Department of Animal and Plant Sciences, University of Sheffield, Alfred Denny Building, Western Bank, Sheffield, S10 2TN, UK
| | - Tristan Quaife
- Department of Meteorology, National Centre for Earth Observation, University of Reading, Reading, RG6 6BX, UK
| | - Peter M van Bodegom
- Institute of Environmental Sciences, Leiden University, 2333 CC, Leiden, the Netherlands
| | - Martin G De Kauwe
- Department of Biological Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Trevor F Keenan
- Earth Sciences Division, Lawrence Berkeley National Lab, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Joanna Joiner
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA
| | - Mark R Lomas
- Department of Animal and Plant Sciences, University of Sheffield, Alfred Denny Building, Western Bank, Sheffield, S10 2TN, UK
| | - Natasha MacBean
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, F-91191, France
| | - Chongang Xu
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, 87544, USA
| | - Xiaojuan Yang
- Oak Ridge National Laboratory, Environmental Sciences Division and Climate Change Science Institute, Oak Ridge, TN, 37830-6301, USA
| | - F Ian Woodward
- Department of Animal and Plant Sciences, University of Sheffield, Alfred Denny Building, Western Bank, Sheffield, S10 2TN, UK
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Thurner M, Beer C, Ciais P, Friend AD, Ito A, Kleidon A, Lomas MR, Quegan S, Rademacher TT, Schaphoff S, Tum M, Wiltshire A, Carvalhais N. Evaluation of climate-related carbon turnover processes in global vegetation models for boreal and temperate forests. GLOBAL CHANGE BIOLOGY 2017; 23:3076-3091. [PMID: 28192628 PMCID: PMC5516177 DOI: 10.1111/gcb.13660] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 12/27/2016] [Accepted: 01/31/2017] [Indexed: 05/29/2023]
Abstract
Turnover concepts in state-of-the-art global vegetation models (GVMs) account for various processes, but are often highly simplified and may not include an adequate representation of the dominant processes that shape vegetation carbon turnover rates in real forest ecosystems at a large spatial scale. Here, we evaluate vegetation carbon turnover processes in GVMs participating in the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP, including HYBRID4, JeDi, JULES, LPJml, ORCHIDEE, SDGVM, and VISIT) using estimates of vegetation carbon turnover rate (k) derived from a combination of remote sensing based products of biomass and net primary production (NPP). We find that current model limitations lead to considerable biases in the simulated biomass and in k (severe underestimations by all models except JeDi and VISIT compared to observation-based average k), likely contributing to underestimation of positive feedbacks of the northern forest carbon balance to climate change caused by changes in forest mortality. A need for improved turnover concepts related to frost damage, drought, and insect outbreaks to better reproduce observation-based spatial patterns in k is identified. As direct frost damage effects on mortality are usually not accounted for in these GVMs, simulated relationships between k and winter length in boreal forests are not consistent between different regions and strongly biased compared to the observation-based relationships. Some models show a response of k to drought in temperate forests as a result of impacts of water availability on NPP, growth efficiency or carbon balance dependent mortality as well as soil or litter moisture effects on leaf turnover or fire. However, further direct drought effects such as carbon starvation (only in HYBRID4) or hydraulic failure are usually not taken into account by the investigated GVMs. While they are considered dominant large-scale mortality agents, mortality mechanisms related to insects and pathogens are not explicitly treated in these models.
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Affiliation(s)
- Martin Thurner
- Department of Environmental Science and Analytical Chemistry (ACES)Stockholm UniversityStockholmSweden
- Bolin Centre for Climate ResearchStockholm UniversityStockholmSweden
| | - Christian Beer
- Department of Environmental Science and Analytical Chemistry (ACES)Stockholm UniversityStockholmSweden
- Bolin Centre for Climate ResearchStockholm UniversityStockholmSweden
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l'Environnement (LSCE)Gif‐sur‐YvetteFrance
| | | | - Akihiko Ito
- National Institute for Environmental StudiesTsukubaJapan
| | - Axel Kleidon
- Max Planck Institute for BiogeochemistryJenaGermany
| | - Mark R. Lomas
- School of Mathematics and StatisticsUniversity of SheffieldSheffieldUK
| | - Shaun Quegan
- School of Mathematics and StatisticsUniversity of SheffieldSheffieldUK
| | | | | | - Markus Tum
- German Aerospace Center (DLR)German Remote Sensing Data Center (DFD)WesslingGermany
| | | | - Nuno Carvalhais
- Max Planck Institute for BiogeochemistryJenaGermany
- CENSEDepartamento de Ciências e Engenharia do AmbienteFaculdade de Ciências e TecnologiaUniversidade NOVA de LisboaCaparicaPortugal
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Ma S, Osuna JL, Verfaillie J, Baldocchi DD. Photosynthetic responses to temperature across leaf-canopy-ecosystem scales: a 15-year study in a Californian oak-grass savanna. PHOTOSYNTHESIS RESEARCH 2017; 132:277-291. [PMID: 28425026 DOI: 10.1007/s11120-017-0388-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 04/13/2017] [Indexed: 06/07/2023]
Abstract
Ecosystem CO2 fluxes measured with eddy-covariance techniques provide a new opportunity to retest functional responses of photosynthesis to abiotic factors at the ecosystem level, but examining the effects of one factor (e.g., temperature) on photosynthesis remains a challenge as other factors may confound under circumstances of natural experiments. In this study, we developed a data mining framework to analyze a set of ecosystem CO2 fluxes measured from three eddy-covariance towers, plus a suite of abiotic variables (e.g., temperature, solar radiation, air, and soil moisture) measured simultaneously, in a Californian oak-grass savanna from 2000 to 2015. Natural covariations of temperature and other factors caused remarkable confounding effects in two particular conditions: lower light intensity at lower temperatures and drier air and soil at higher temperatures. But such confounding effects may cancel out. At the ecosystem level, photosynthetic responses to temperature did follow a quadratic function on average. The optimum value of photosynthesis occurred within a narrow temperature range (i.e., optimum temperature, T opt): 20.6 ± 0.6, 18.5 ± 0.7, 19.2 ± 0.5, and 19.0 ± 0.6 °C for the oak canopy, understory grassland, entire savanna, and open grassland, respectively. This paradigm confirms that photosynthesis response to ambient temperature changes is a functional relationship consistent across leaf-canopy-ecosystem scales. Nevertheless, T opt can shift with variations in light intensity, air dryness, or soil moisture. These findings will pave the way to a direct determination of thermal optima and limits of ecosystem photosynthesis, which can in turn provide a rich resource for baseline thresholds and dynamic response functions required for predicting global carbon balance and geographic shifts of vegetative communities in response to climate change.
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Affiliation(s)
- Siyan Ma
- Ecosystem Science Division, Department of Environmental Science, Policy and Management, University of California at Berkeley, 137 Mulford Hall # 3114, Berkeley, CA, 94720, USA.
| | - Jessica L Osuna
- Atmospheric, Earth, and Energy Division, Lawrence Livermore National Laboratory, 7000 East Avenue L-103, Livermore, CA, 94550, USA
| | - Joseph Verfaillie
- Ecosystem Science Division, Department of Environmental Science, Policy and Management, University of California at Berkeley, 137 Mulford Hall # 3114, Berkeley, CA, 94720, USA
| | - Dennis D Baldocchi
- Ecosystem Science Division, Department of Environmental Science, Policy and Management, University of California at Berkeley, 137 Mulford Hall # 3114, Berkeley, CA, 94720, USA
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37
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Devine AP, McDonald RA, Quaife T, Maclean IMD. Determinants of woody encroachment and cover in African savannas. Oecologia 2017; 183:939-951. [PMID: 28116524 PMCID: PMC5348564 DOI: 10.1007/s00442-017-3807-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 01/01/2017] [Indexed: 11/17/2022]
Abstract
Savanna ecosystems are an integral part of the African landscape and sustain the livelihoods of millions of people. Woody encroachment in savannas is a widespread phenomenon but its causes are widely debated. We review the extensive literature on woody encroachment to help improve understanding of the possible causes and to highlight where and how future scientific efforts to fully understand these causes should be focused. Rainfall is the most important determinant of maximum woody cover across Africa, but fire and herbivory interact to reduce woody cover below the maximum at many locations. We postulate that woody encroachment is most likely driven by CO2 enrichment and propose a two-system conceptual framework, whereby mechanisms of woody encroachment differ depending on whether the savanna is a wet or dry system. In dry savannas, the increased water-use efficiency in plants relaxes precipitation-driven constraints and increases woody growth. In wet savannas, the increase of carbon allocation to tree roots results in faster recovery rates after disturbance and a greater likelihood of reaching sexual maturity. Our proposed framework can be tested using a mixture of experimental and earth observational techniques. At a local level, changes in precipitation, burning regimes or herbivory could be driving woody encroachment, but are unlikely to be the explanation of this continent-wide phenomenon.
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Affiliation(s)
- Aisling P. Devine
- Department of Biosciences, Wallace Building, Swansea University, Singleton Park, Swansea, SA2 8PP UK
- Environment and Sustainability Institute, University of Exeter, Cornwall Campus, Penryn, TR10 9EZ UK
| | - Robbie A. McDonald
- Environment and Sustainability Institute, University of Exeter, Cornwall Campus, Penryn, TR10 9EZ UK
| | - Tristan Quaife
- Department of Meteorology, University of Reading, Earley Gate, PO Box 243, Reading, RG6 6BB UK
| | - Ilya M. D. Maclean
- Environment and Sustainability Institute, University of Exeter, Cornwall Campus, Penryn, TR10 9EZ UK
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38
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Song X, Zeng X. Evaluating the responses of forest ecosystems to climate change and CO 2 using dynamic global vegetation models. Ecol Evol 2017; 7:997-1008. [PMID: 28168035 PMCID: PMC5288257 DOI: 10.1002/ece3.2735] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Revised: 12/10/2016] [Accepted: 12/18/2016] [Indexed: 11/08/2022] Open
Abstract
The climate has important influences on the distribution and structure of forest ecosystems, which may lead to vital feedback to climate change. However, much of the existing work focuses on the changes in carbon fluxes or water cycles due to climate change and/or atmospheric CO 2, and few studies have considered how and to what extent climate change and CO 2 influence the ecosystem structure (e.g., fractional coverage change) and the changes in the responses of ecosystems with different characteristics. In this work, two dynamic global vegetation models (DGVMs): IAP-DGVM coupled with CLM3 and CLM4-CNDV, were used to investigate the response of the forest ecosystem structure to changes in climate (temperature and precipitation) and CO 2 concentration. In the temperature sensitivity tests, warming reduced the global area-averaged ecosystem gross primary production in the two models, which decreased global forest area. Furthermore, the changes in tree fractional coverage (ΔFtree; %) from the two models were sensitive to the regional temperature and ecosystem structure, i.e., the mean annual temperature (MAT; °C) largely determined whether ΔFtree was positive or negative, while the tree fractional coverage (Ftree; %) played a decisive role in the amplitude of ΔFtree around the globe, and the dependence was more remarkable in IAP-DGVM. In cases with precipitation change, Ftree had a uniformly positive relationship with precipitation, especially in the transition zones of forests (30% < Ftree < 60%) for IAP-DGVM and in semiarid and arid regions for CLM4-CNDV. Moreover, ΔFtree had a stronger dependence on Ftree than on the mean annual precipitation (MAP; mm/year). It was also demonstrated that both models captured the fertilization effects of the CO 2 concentration.
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Affiliation(s)
- Xiang Song
- International Center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China
| | - Xiaodong Zeng
- International Center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China; Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology Nanjing China; University of Chinese Academy of Sciences Beijing China
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39
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Atkin OK, Bahar NHA, Bloomfield KJ, Griffin KL, Heskel MA, Huntingford C, de la Torre AM, Turnbull MH. Leaf Respiration in Terrestrial Biosphere Models. ADVANCES IN PHOTOSYNTHESIS AND RESPIRATION 2017. [DOI: 10.1007/978-3-319-68703-2_6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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40
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van Wilgen BW, Carruthers J, Cowling RM, Esler KJ, Forsyth AT, Gaertner M, Hoffman MT, Kruger FJ, Midgley GF, Palmer G, Pence GQK, Raimondo DC, Richardson DM, van Wilgen NJ, Wilson JR. Ecological research and conservation management in the Cape Floristic Region between 1945 and 2015: History, current understanding and future challenges. ACTA ACUST UNITED AC 2016. [DOI: 10.1080/0035919x.2016.1225607] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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41
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Ortega RA, Mahnert A, Berg C, Müller H, Berg G. The plant is crucial: specific composition and function of the phyllosphere microbiome of indoor ornamentals. FEMS Microbiol Ecol 2016; 92:fiw173. [PMID: 27624084 DOI: 10.1093/femsec/fiw173] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/14/2016] [Indexed: 11/14/2022] Open
Abstract
The plant microbiome is a key determinant of plant health. Less is known about the phyllosphere microbiota and its driving factors in built environments. To study the variability of the microbiome in relation to plant genotype and climate under different controlled conditions, we investigated 14 phylogenetically diverse plant species grown in the greenhouses of the Botanical Garden in Graz (Austria). All investigated plants showed specific bacterial abundances of up to 10(6) CFU cm(-2) on their leaves. Bacterial diversity (H('): 2.4-7.9) and number of putative OTUs (461-2013) were strongly plant species dependent. Statistical analysis showed a significantly higher correlation of community composition to plant genotype in comparison to the ambient climatic variables. In addition to the microbiome structure, we studied the antagonistic potential towards the foliar pathogen Botrytis cinerea as functional indicator. A high proportion of isolates (up to 58%) were able to inhibit pathogen growth by production of volatile organic compounds (VOCs). Data of structure and function were linked: frequently isolated VOCs producers (e.g. Bacillus and Stenotrophomonas) were highly present in phyllosphere communities, which were dominated by members of Firmicutes This study indicates that indoor ornamentals feature a distinct, stable microbiota on leaves irrespective of the indoor climate.
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Affiliation(s)
- Rocel Amor Ortega
- Institute of Environmental Biotechnology, Graz University of Technology, 8010 Graz, Austria University of the Philippines Baguio, 2600 Baguio City, Philippines
| | - Alexander Mahnert
- Institute of Environmental Biotechnology, Graz University of Technology, 8010 Graz, Austria
| | - Christian Berg
- Institute of Plant Sciences, University of Graz, 8010 Graz, Austria
| | - Henry Müller
- Institute of Environmental Biotechnology, Graz University of Technology, 8010 Graz, Austria
| | - Gabriele Berg
- Institute of Environmental Biotechnology, Graz University of Technology, 8010 Graz, Austria
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42
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Medlyn BE, De Kauwe MG, Zaehle S, Walker AP, Duursma RA, Luus K, Mishurov M, Pak B, Smith B, Wang YP, Yang X, Crous KY, Drake JE, Gimeno TE, Macdonald CA, Norby RJ, Power SA, Tjoelker MG, Ellsworth DS. Using models to guide field experiments: a priori predictions for the CO2 response of a nutrient- and water-limited native Eucalypt woodland. GLOBAL CHANGE BIOLOGY 2016; 22:2834-51. [PMID: 26946185 DOI: 10.1111/gcb.13268] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 02/01/2016] [Accepted: 02/09/2016] [Indexed: 05/27/2023]
Abstract
The response of terrestrial ecosystems to rising atmospheric CO2 concentration (Ca ), particularly under nutrient-limited conditions, is a major uncertainty in Earth System models. The Eucalyptus Free-Air CO2 Enrichment (EucFACE) experiment, recently established in a nutrient- and water-limited woodland presents a unique opportunity to address this uncertainty, but can best do so if key model uncertainties have been identified in advance. We applied seven vegetation models, which have previously been comprehensively assessed against earlier forest FACE experiments, to simulate a priori possible outcomes from EucFACE. Our goals were to provide quantitative projections against which to evaluate data as they are collected, and to identify key measurements that should be made in the experiment to allow discrimination among alternative model assumptions in a postexperiment model intercomparison. Simulated responses of annual net primary productivity (NPP) to elevated Ca ranged from 0.5 to 25% across models. The simulated reduction of NPP during a low-rainfall year also varied widely, from 24 to 70%. Key processes where assumptions caused disagreement among models included nutrient limitations to growth; feedbacks to nutrient uptake; autotrophic respiration; and the impact of low soil moisture availability on plant processes. Knowledge of the causes of variation among models is now guiding data collection in the experiment, with the expectation that the experimental data can optimally inform future model improvements.
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Affiliation(s)
- Belinda E Medlyn
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
- Department of Biological Sciences, Macquarie University, North Ryde, NSW, 2109, Australia
| | - Martin G De Kauwe
- Department of Biological Sciences, Macquarie University, North Ryde, NSW, 2109, Australia
| | - Sönke Zaehle
- Biogeochemical Integration Department, Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, D-07745, Jena, Germany
| | - Anthony P Walker
- Oak Ridge National Laboratory, Environmental Sciences Division and Climate Change Science Institute, 1 Bethel Valley Road, Oak Ridge, TN, USA
| | - Remko A Duursma
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Kristina Luus
- Biogeochemical Integration Department, Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, D-07745, Jena, Germany
| | - Mikhail Mishurov
- Department of Physical Geography and Ecosystem Science, Lund University, Sölvegatan 12, 22362, Lund, Sweden
| | - Bernard Pak
- CSIRO Oceans and Atmosphere Flagship, Private Bag 1, Aspendale, Vic., 3195, Australia
| | - Benjamin Smith
- Department of Physical Geography and Ecosystem Science, Lund University, Sölvegatan 12, 22362, Lund, Sweden
| | - Ying-Ping Wang
- CSIRO Oceans and Atmosphere Flagship, Private Bag 1, Aspendale, Vic., 3195, Australia
| | - Xiaojuan Yang
- Oak Ridge National Laboratory, Environmental Sciences Division and Climate Change Science Institute, 1 Bethel Valley Road, Oak Ridge, TN, USA
| | - Kristine Y Crous
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - John E Drake
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Teresa E Gimeno
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
- ISPA, Bordeaux Science Agro, INRA, 33140, Villenave d'Ornon, France
| | - Catriona A Macdonald
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Richard J Norby
- Oak Ridge National Laboratory, Environmental Sciences Division and Climate Change Science Institute, 1 Bethel Valley Road, Oak Ridge, TN, USA
| | - Sally A Power
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Mark G Tjoelker
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - David S Ellsworth
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
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43
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Li T, Zhang Q, Zhang W, Wang G, Lu Y, Yu L, Zhang R. Prediction CH4 Emissions from the Wetlands in the Sanjiang Plain of Northeastern China in the 21st Century. PLoS One 2016; 11:e0158872. [PMID: 27409586 PMCID: PMC4943593 DOI: 10.1371/journal.pone.0158872] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 06/23/2016] [Indexed: 11/19/2022] Open
Abstract
The Sanjiang Plain has been experienced significant wetland loss due to expanded agricultural activities, and will be potentially restored by the China National Wetland Conservation Action Plan (NWCP) in future. The objective of this study is to evaluate the impact of future climate warming and wetland restoration on wetland CH4 emissions in northeast China. We used an atmosphere-vegetation interaction model (AVIM2) to drive a modified biogeophysical model (CH4MODwetland), and projected CH4 flux variations from the Sanjiang Plain wetlands under different Representative Concentration Pathway scenarios throughout the 21st century. Model validation showed that the regressions between the observed and simulated CH4 fluxes by the modified model produced an R2 of 0.49 with a slope of 0.87 (p<0.001, n = 237). According to the AVIM2 simulation, the net primary productivity of the Sanjiang Plain wetlands will increase by 38.2 g m-2 yr-1, 116.6 g m-2 yr-1 and 250.4 g m-2 yr-1 under RCP 2.6, RCP 4.5 and RCP 8.5, respectively, by the end of this century. For RCP 2.6, 4.5 and 8.5 scenarios, the CH4 fluxes will increase by 5.7 g m-2 yr-1, 57.5 g m-2 yr-1 and 112.2 g m-2 yr-1. Combined with the wetland restoration, the regional emissions will increase by 0.18‒1.52 Tg. The CH4 emissions will be stimulated by climate change and wetland restoration. Regional wetland restoration planning should be directed against different climate scenarios in order to suppress methane emissions.
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Affiliation(s)
- Tingting Li
- LAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China
| | - Qing Zhang
- LAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China
| | - Wen Zhang
- LAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China
- * E-mail:
| | - Guocheng Wang
- LAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China
| | - Yanyu Lu
- Anhui Climate Center, Hefei, 230031, China
| | - Lijun Yu
- LAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China
| | - Ran Zhang
- CCRC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China
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Rezende LFC, Arenque BC, Aidar ST, Moura MSB, Von Randow C, Tourigny E, Menezes RSC, Ometto JPHB. Evolution and challenges of dynamic global vegetation models for some aspects of plant physiology and elevated atmospheric CO2. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2016; 60:945-955. [PMID: 26498437 DOI: 10.1007/s00484-015-1087-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Revised: 10/06/2015] [Accepted: 10/13/2015] [Indexed: 06/05/2023]
Abstract
Dynamic global vegetation models (DGVMs) simulate surface processes such as the transfer of energy, water, CO2, and momentum between the terrestrial surface and the atmosphere, biogeochemical cycles, carbon assimilation by vegetation, phenology, and land use change in scenarios of varying atmospheric CO2 concentrations. DGVMs increase the complexity and the Earth system representation when they are coupled with atmospheric global circulation models (AGCMs) or climate models. However, plant physiological processes are still a major source of uncertainty in DGVMs. The maximum velocity of carboxylation (Vcmax), for example, has a direct impact over productivity in the models. This parameter is often underestimated or imprecisely defined for the various plant functional types (PFTs) and ecosystems. Vcmax is directly related to photosynthesis acclimation (loss of response to elevated CO2), a widely known phenomenon that usually occurs when plants are subjected to elevated atmospheric CO2 and might affect productivity estimation in DGVMs. Despite this, current models have improved substantially, compared to earlier models which had a rudimentary and very simple representation of vegetation-atmosphere interactions. In this paper, we describe this evolution through generations of models and the main events that contributed to their improvements until the current state-of-the-art class of models. Also, we describe some main challenges for further improvements to DGVMs.
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Affiliation(s)
- L F C Rezende
- Earth System Science Center, National Institute for Space Research (INPE), Av. dos Astronautas, 1758 - Jd. da Granja, CEP: 12227-010, São José dos Campos, SP, Brazil.
| | - B C Arenque
- Botany Department, University of São Paulo (USP), R. do Matão, 277, CEP: 05508-090, Butantã, SP, Brazil
| | - S T Aidar
- Embrapa Tropical Semiarid Brazilian Agricultural Research Corporation (EMBRAPA), Rodovia BR-428, Km 152, Zona Rural, CEP: 56302-970, Petrolina, PE, Brazil
| | - M S B Moura
- Embrapa Tropical Semiarid Brazilian Agricultural Research Corporation (EMBRAPA), Rodovia BR-428, Km 152, Zona Rural, CEP: 56302-970, Petrolina, PE, Brazil
| | - C Von Randow
- Earth System Science Center, National Institute for Space Research (INPE), Av. dos Astronautas, 1758 - Jd. da Granja, CEP: 12227-010, São José dos Campos, SP, Brazil
| | - E Tourigny
- Earth System Science Center, National Institute for Space Research (INPE), Av. dos Astronautas, 1758 - Jd. da Granja, CEP: 12227-010, São José dos Campos, SP, Brazil
| | - R S C Menezes
- Federal University of Pernambuco (UFPE), Av. Prof. Luis Freire, 1000, CEP: 50740-540, Cidade Universitária, Recife, PE, Brazil
| | - J P H B Ometto
- Earth System Science Center, National Institute for Space Research (INPE), Av. dos Astronautas, 1758 - Jd. da Granja, CEP: 12227-010, São José dos Campos, SP, Brazil
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45
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Bellasio C, Beerling DJ, Griffiths H. An Excel tool for deriving key photosynthetic parameters from combined gas exchange and chlorophyll fluorescence: theory and practice. PLANT, CELL & ENVIRONMENT 2016; 39:1180-97. [PMID: 25923517 DOI: 10.1111/pce.12560] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 02/10/2015] [Accepted: 02/25/2015] [Indexed: 05/23/2023]
Abstract
Combined photosynthetic gas exchange and modulated fluorometres are widely used to evaluate physiological characteristics associated with phenotypic and genotypic variation, whether in response to genetic manipulation or resource limitation in natural vegetation or crops. After describing relatively simple experimental procedures, we present the theoretical background to the derivation of photosynthetic parameters, and provide a freely available Excel-based fitting tool (EFT) that will be of use to specialists and non-specialists alike. We use data acquired in concurrent variable fluorescence-gas exchange experiments, where A/Ci and light-response curves have been measured under ambient and low oxygen. From these data, the EFT derives light respiration, initial PSII (photosystem II) photochemical yield, initial quantum yield for CO2 fixation, fraction of incident light harvested by PSII, initial quantum yield for electron transport, electron transport rate, rate of photorespiration, stomatal limitation, Rubisco (ribulose 1·5-bisphosphate carboxylase/oxygenase) rate of carboxylation and oxygenation, Rubisco specificity factor, mesophyll conductance to CO2 diffusion, light and CO2 compensation point, Rubisco apparent Michaelis-Menten constant, and Rubisco CO2 -saturated carboxylation rate. As an example, a complete analysis of gas exchange data on tobacco plants is provided. We also discuss potential measurement problems and pitfalls, and suggest how such empirical data could subsequently be used to parameterize predictive photosynthetic models.
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Affiliation(s)
- Chandra Bellasio
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
| | - David J Beerling
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
| | - Howard Griffiths
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK
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46
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Bayesian Analysis of Uncertainty in the GlobCover 2009 Land Cover Product at Climate Model Grid Scale. REMOTE SENSING 2016. [DOI: 10.3390/rs8040314] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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47
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Ito A, Nishina K, Noda HM. Evaluation of global warming impacts on the carbon budget of terrestrial ecosystems in monsoon Asia: a multi-model analysis. Ecol Res 2016. [DOI: 10.1007/s11284-016-1354-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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48
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Moore GW, Edgar CB, Vogel JG, Washington-Allen RA, March RG, Zehnder R. Tree mortality from an exceptional drought spanning mesic to semiarid ecoregions. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2016; 26:602-11. [PMID: 27209798 DOI: 10.1890/15-0330] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Significant areas of the southern USA periodically experience intense drought that can lead to episodic tree mortality events. Because drought tolerance varies among species and size of trees, such events can alter the structure and function of terrestrial ecosystem in ways that are difficult to detect with local data sets or solely with remote-sensing platforms. We investigated a widespread tree mortality event that resulted from the worst 1-year drought on record for the state of Texas, USA. The drought affected ecoregions spanning mesic to semiarid climate zones and provided a unique opportunity to test hypotheses related to how trees of varying genus and size were affected. The study was based on an extensive set of 599 distributed plots, each 0.16 ha, surveyed in the summer following the drought. In each plot, dead trees larger than 12.7 cm in diameter were counted, sized, and identified to the genus level. Estimates of total mortality were obtained for each of 10 regions using a combination of design-based estimators and calibrated remote sensing using MODIS 1-yr change in normalized difference vegetation index products developed by the U.S. Forest Service. As compared with most of the publicized extreme die-off events, this study documents relatively low rates of mortality occurring over a very large area. However, statewide, regional tree mortality was massive, with an estimated 6.2% of the live trees perishing, nearly nine times greater than normal annual mortality. Dead tree diameters averaged larger than the live trees for most ecoregions, and this trend was most pronounced in the wetter climate zones, suggesting a potential re-ordering of species dominance and downward trend in tree size that was specific to climatic regions. The net effect on carbon storage was estimated to be a redistribution of 24-30 Tg C from the live tree to dead tree carbon pool. The dead tree survey documented drought mortality in more than 29 genera across all regions, and surprisingly, drought resistant and sensitive species fared similarly in some regions. Both angiosperms and gymnosperms were affected. These results highlight that drought-driven mortality alters forest structure differently across climatic regions and genera.
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49
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Le Maitre DC, Gush MB, Dzikiti S. Impacts of invading alien plant species on water flows at stand and catchment scales. AOB PLANTS 2015; 7:plv043. [PMID: 25935861 PMCID: PMC4480063 DOI: 10.1093/aobpla/plv043] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 03/26/2015] [Indexed: 06/04/2023]
Abstract
There have been many studies of the diverse impacts of invasions by alien plants but few have assessed impacts on water resources. We reviewed the information on the impacts of invasions on surface runoff and groundwater resources at stand to catchment scales and covering a full annual cycle. Most of the research is South African so the emphasis is on South Africa's major invaders with data from commercial forest plantations where relevant. Catchment studies worldwide have shown that changes in vegetation structure and the physiology of the dominant plant species result in changes in surface runoff and groundwater discharge, whether they involve native or alien plant species. Where there is little change in vegetation structure [e.g. leaf area (index), height, rooting depth and seasonality] the effects of invasions generally are small or undetectable. In South Africa, the most important woody invaders typically are taller and deeper rooted than the native species. The impacts of changes in evaporation (and thus runoff) in dryland settings are constrained by water availability to the plants and, thus, by rainfall. Where the dryland invaders are evergreen and the native vegetation (grass) is seasonal, the increases can reach 300-400 mm/year. Where the native vegetation is evergreen (shrublands) the increases are ∼200-300 mm/year. Where water availability is greater (riparian settings or shallow water tables), invading tree water-use can reach 1.5-2.0 times that of the same species in a dryland setting. So, riparian invasions have a much greater impact per unit area invaded than dryland invasions. The available data are scattered and incomplete, and there are many gaps and issues that must be addressed before a thorough understanding of the impacts at the site scale can be gained and used in extrapolating to watershed scales, and in converting changes in flows to water supply system yields.
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Affiliation(s)
- D C Le Maitre
- CSIR Natural Resources and the Environment, PO Box 320, Stellenbosch 7599, South Africa Centre for Invasion Biology, Department of Botany and Zoology, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa
| | - M B Gush
- CSIR Natural Resources and the Environment, PO Box 320, Stellenbosch 7599, South Africa
| | - S Dzikiti
- CSIR Natural Resources and the Environment, PO Box 320, Stellenbosch 7599, South Africa
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50
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Abramoff RZ, Finzi AC. Are above- and below-ground phenology in sync? THE NEW PHYTOLOGIST 2015; 205:1054-1061. [PMID: 25729805 DOI: 10.1111/nph.13111] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Globally, root production accounts for 33-67% of terrestrial net primary productivity and influences decomposition via root production and turnover, carbon (C) allocation to mycorrhizal fungi and root exudation. As recognized above ground, the timing of phenological events affects terrestrial C balance, yet there is no parallel understanding for below-ground phenology. In this paper we examine the phenology of root production and its relationship to temperature, soil moisture, and above-ground phenology. Synthesizing 87 observations of whole-plant phenology from 40 studies, we found that, on average, root growth occurs 25 ± 8 d after shoot growth but that the offset between the peak in root and shoot growth varies > 200 d across biomes (boreal, temperate, Mediterranean, and subtropical). Root and shoot growth are positively correlated with median monthly temperature and mean monthly precipitation in boreal, temperate, and subtropical biomes. However, a temperature hysteresis in these biomes leads to the hypothesis that internal controls over C allocation to roots are an equally, if not more, important driver of phenology. The specific mechanisms are as yet unclear but they are likely mediated by some combination of photoassimilate supply, hormonal signaling, and growth form.
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