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Song Y, Liu T, Jiao R, Lu Y, Sun K, Zhao K, Wen Y, Shi W, Song S. Nanoscale chestnut soil pore characteristics changes induced by non-growing season precipitation in a temperate grassland. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 948:174818. [PMID: 39025141 DOI: 10.1016/j.scitotenv.2024.174818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Revised: 07/12/2024] [Accepted: 07/13/2024] [Indexed: 07/20/2024]
Abstract
Changes in precipitation patterns during the non-growing season can affect soil moisture storage in temperate grasslands. However, there is a lack of comprehensive understanding regarding how these changes influence microscale soil pore characteristics and nutrient cycling in the context of climate change. Therefore, we carried out a 3-year artificial precipitation experiment during the non-growing season, along with N2 adsorption experiments of soil pore distribution and surveys of soil nutrient content. The aim was to clarify the influence of non-growing season precipitation variations on nanoscale soil pore characteristics and explore the potential correlations of the soil physicochemical properties. The results showed that: (1) The precipitation sheltering treatment during the non-growing season led to a significant 9.80 % increase in soil porosity at the 0-15 cm depth compared to the control. (2) Compared to the control, alterations in non-growing season precipitation (both increase and sheltering treatments) led to a significant increase in soil specific surface area (SSA), with an average increase of 23.2 %. Additionally, soil micropores, mesopores, macropores, and total pore volume (PV) increased by an average of 24.2 %, 14.0 %, 30.1 %, and 23.1 %, respectively. (3) Significant correlations were observed between soil microscale pore characteristics and soil C, soil organic matter (SOM), C: N ratio, and available P (AP). Redundancy analysis showed that soil microscale pore characteristics effectively accounted for the variations in soil nutrients with an explanatory degree of 94.23 %. (4) Influence pathways analysis by structural equation modeling indicated that dramatic variability in non-growing season precipitation promoted increases in mesopore and macropore volume, as well as the transformation of mesopores into macropores, thereby facilitating soil carbon accumulation. Our study suggests that soil microscale pore characteristics, acquired through adsorption experiments, assist in elucidating these potential synergistic mechanisms among physicochemical properties under varying non-growing season precipitation patterns. Given the escalating impacts of climate change, our findings provide novel insights and evidence for the assessment of climate change impacts in temperate arid grassland ecosystems.
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Affiliation(s)
- Yifan Song
- Yinshanbeilu Grassland Eco-hydrology National Observation and Research Station, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100044, China
| | - Tiejun Liu
- Yinshanbeilu Grassland Eco-hydrology National Observation and Research Station, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100044, China.
| | - Rui Jiao
- Yinshanbeilu Grassland Eco-hydrology National Observation and Research Station, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Yajing Lu
- Beijing Water Science and Technology Institute, Beijing 100048, China
| | - Kai Sun
- College of Energy and Transportation Engineering of Inner Mongolia Agricultural University, Hohhot 010021, China
| | - Keke Zhao
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100044, China
| | - Yunhao Wen
- College of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
| | - Wei Shi
- College of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
| | - Shaomai Song
- Ruyang Office of Water Conservation, Luoyang 471200, China
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Männistö MK, Ahonen SHK, Ganzert L, Tiirola M, Stark S, Häggblom MM. Bacterial and fungal communities in sub-Arctic tundra heaths are shaped by contrasting snow accumulation and nutrient availability. FEMS Microbiol Ecol 2024; 100:fiae036. [PMID: 38549428 PMCID: PMC10996926 DOI: 10.1093/femsec/fiae036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 02/26/2024] [Accepted: 03/27/2024] [Indexed: 04/06/2024] Open
Abstract
Climate change is affecting winter snow conditions significantly in northern ecosystems but the effects of the changing conditions for soil microbial communities are not well-understood. We utilized naturally occurring differences in snow accumulation to understand how the wintertime subnivean conditions shape bacterial and fungal communities in dwarf shrub-dominated sub-Arctic Fennoscandian tundra sampled in mid-winter, early, and late growing season. Phospholipid fatty acid (PLFA) and quantitative PCR analyses indicated that fungal abundance was higher in windswept tundra heaths with low snow accumulation and lower nutrient availability. This was associated with clear differences in the microbial community structure throughout the season. Members of Clavaria spp. and Sebacinales were especially dominant in the windswept heaths. Bacterial biomass proxies were higher in the snow-accumulating tundra heaths in the late growing season but there were only minor differences in the biomass or community structure in winter. Bacterial communities were dominated by members of Alphaproteobacteria, Actinomycetota, and Acidobacteriota and were less affected by the snow conditions than the fungal communities. The results suggest that small-scale spatial patterns in snow accumulation leading to a mosaic of differing tundra heath vegetation shapes bacterial and fungal communities as well as soil carbon and nutrient availability.
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Affiliation(s)
- Minna K Männistö
- Natural Resources Institute Finland, Ounasjoentie 6, FI-96200 Rovaniemi, Finland
| | - Saija H K Ahonen
- Ecology and Genetics Research Unit, University of Oulu, Pentti Kaiteran katu 1, FI-90014 Oulu, Finland
| | - Lars Ganzert
- Natural Resources Institute Finland, Ounasjoentie 6, FI-96200 Rovaniemi, Finland
- Plankton and Microbial Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Zur alten Fischerhütte 2, 16775 Stechlin, Germany
| | - Marja Tiirola
- Department of Biological and Environmental Science, University of Jyväskylä, Survontie 9, FI-40014 Jyväskylä, Finland
| | - Sari Stark
- Arctic Centre, University of Lapland, Pohjoisranta 4, Fl-96101 Rovaniemi, Finland
| | - Max M Häggblom
- Natural Resources Institute Finland, Ounasjoentie 6, FI-96200 Rovaniemi, Finland
- Department of Biochemistry and Microbiology, Rutgers University, 76 Lipman Drive, New Brunswick, NJ 08901, United States
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Buttler A, Teuscher R, Deschamps N, Gavazov K, Bragazza L, Mariotte P, Schlaepfer R, Jassey VEJ, Freund L, Cuartero J, Quezada JC, Frey B. Impacts of snow-farming on alpine soil and vegetation: A case study from the Swiss Alps. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166225. [PMID: 37586524 DOI: 10.1016/j.scitotenv.2023.166225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 08/08/2023] [Accepted: 08/09/2023] [Indexed: 08/18/2023]
Abstract
Snow-farming is one of the adaptive strategies used to face the snow deficit in ski resorts. We studied the impact of a shifting snow-farming technique on a pasture slope in Adelboden, Switzerland. Specifically, we compared plots covered by a compressed snow pile for 1.5, 2.5 or 3.5 years, which then recovered from the snow cover for three, two or one vegetation seasons, respectively, with control plots situated around the snow pile. In plots with >1.5 years of compressed snow pile, plant mortality was high, recovery of vegetation was very slow, and few plant species recolonized the bare surface. Soil biological activity decreased persistently under prolonged snow cover, as indicated by reduced soil respiration. The prolonged absence of fresh plant litter and root exudates led to carbon (C) limitation for soil microbial respiration, which resulted in a significant decrease in the ratio of total organic carbon to total nitrogen (TOC/TN) under the snow pile. Microbial C, nitrogen (N) and phosphorus (P) immobilization decreased, while dissolved N concentration increased with compressed snow cover. Longer snow cover and a subsequent shorter recovery period led to higher microbial C/P and N/P but lower microbial C/N. Nitrate and ammonium were released massively once the biological activity resumed after snow clearance and soil aeration. The soil microbial community composition persistently shifted towards oxygen-limited microbes with prolonged compressed snow cover. This shift reflected declines in the abundance of sensitive microorganisms, such as plant-associated symbionts, due to plant mortality or root die-off. In parallel, resistant taxa that benefit from environmental changes increased, including facultative anaerobic bacteria (Bacteroidota, Chloroflexota), obligate anaerobes (Euryarchaeota), and saprophytic plant degraders. We recommend keeping snow piles in the same spot year after year to minimize the area of the impacted soil surface and plan from the beginning soil and ecosystem restoration measures.
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Affiliation(s)
- Alexandre Buttler
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 2, 1015 Lausanne, Switzerland; Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Site Lausanne, Station 2, 1015 Lausanne, Switzerland.
| | | | - Nicolas Deschamps
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 2, 1015 Lausanne, Switzerland
| | - Konstantin Gavazov
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Site Lausanne, Station 2, 1015 Lausanne, Switzerland
| | - Luca Bragazza
- Agroscope, Field-Crop Systems and Plant Nutrition, Route de Duillier 50, P.O. Box 1012, CH-1260 Nyon, Switzerland
| | - Pierre Mariotte
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 2, 1015 Lausanne, Switzerland; Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Site Lausanne, Station 2, 1015 Lausanne, Switzerland; Agroscope, Grazing Systems Group, 1725 Posieux, Switzerland
| | - Rodolphe Schlaepfer
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 2, 1015 Lausanne, Switzerland
| | - Vincent E J Jassey
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 2, 1015 Lausanne, Switzerland; Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Site Lausanne, Station 2, 1015 Lausanne, Switzerland; Laboratoire Ecologie Fonctionnelle et Environnement, Université Paul Sabatier, CNRS, 31062 Toulouse Cedex, France
| | - Lucas Freund
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 2, 1015 Lausanne, Switzerland; Agroscope, Field-Crop Systems and Plant Nutrition, Route de Duillier 50, P.O. Box 1012, CH-1260 Nyon, Switzerland
| | - Jessica Cuartero
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, 8903 Birmensdorf, Switzerland
| | - Juan Carlos Quezada
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 2, 1015 Lausanne, Switzerland; Agroscope, Field-Crop Systems and Plant Nutrition, Route de Duillier 50, P.O. Box 1012, CH-1260 Nyon, Switzerland; Asian School of Environment, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
| | - Beat Frey
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, 8903 Birmensdorf, Switzerland
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Zhang R, Fu X, Zhong H, Sui X, Liu Y. Changes in Soil Bacterial Community and Function in Winter Following Long-Term Nitrogen (N) Deposition in Wetland Soil in Sanjiang Plain, China. Microorganisms 2023; 11:2634. [PMID: 38004646 PMCID: PMC10673031 DOI: 10.3390/microorganisms11112634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 10/16/2023] [Accepted: 10/23/2023] [Indexed: 11/26/2023] Open
Abstract
N deposition is a key factor affecting the composition and function of soil microbial communities in wetland ecosystems. Previous studies mainly focused on the effects of N deposition in the soil during the growing season (summer and autumn). Here, we focused on the response of the soil microbial community structure and function in winter. Soil from the Sanjiang Plain wetland, China, that had been treated for the past 11 years by using artificial N deposition at three levels (no intervention in N0, N deposition with 4 g N m-2 yr-1 in N1, and with 8 g N m-2 yr-1 in N2). Soil characteristics were determined and the bacterial composition and function was characterized using high-throughput sequence technology. The N deposition significantly reduced the soil bacterial diversity detected in winter compared with the control N0, and it significantly changed the composition of the bacterial community. At the phylum level, the high N deposition (N2) increased the relative abundance of Acidobacteria and decreased that of Myxococcota and Gemmatimonadota compared with N0. In soil from N2, the relative abundance of the general Candidatus_Solibacter and Bryobacter was significantly increased compared with N0. Soil pH, soil organic carbon (SOC), and total nitrogen (TN) were the key factors affecting the soil bacterial diversity and composition in winter. Soil pH was correlated with soil carbon cycling, probably due to its significant correlation with aerobic_chemoheterotrophy. The results show that a long-term N deposition reduces soil nutrients in winter wetlands and decreases soil bacterial diversity, resulting in a negative impact on the Sanjiang plain wetland. This study contributes to a better understanding of the winter responses of soil microbial community composition and function to the N deposition in temperate wetland ecosystems.
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Affiliation(s)
- Rongtao Zhang
- Institution of Nature and Ecology, Heilongjiang Academy of Sciences, Harbin 150040, China; (R.Z.); (X.F.); (H.Z.)
| | - Xiaoyu Fu
- Institution of Nature and Ecology, Heilongjiang Academy of Sciences, Harbin 150040, China; (R.Z.); (X.F.); (H.Z.)
| | - Haixiu Zhong
- Institution of Nature and Ecology, Heilongjiang Academy of Sciences, Harbin 150040, China; (R.Z.); (X.F.); (H.Z.)
| | - Xin Sui
- Heilongjiang Provincial Key Laboratory of Ecological Restoration and Resource Utilization for Cold Region, School of Life Sciences, Heilongjiang University, Harbin 150040, China
| | - Yingnan Liu
- Institution of Nature and Ecology, Heilongjiang Academy of Sciences, Harbin 150040, China; (R.Z.); (X.F.); (H.Z.)
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Xie Y, Zhang W, Guo Z, Du X, Fan L, Chen S, Dong Y. Effects of vegetation succession on soil microbial stoichiometry in Phyllstachys edulis stands following abandonment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 895:164971. [PMID: 37336394 DOI: 10.1016/j.scitotenv.2023.164971] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 06/14/2023] [Accepted: 06/15/2023] [Indexed: 06/21/2023]
Abstract
Moso bamboo (Phyllostachys edulis) is China's most important economic bamboo species. With a continuous decline in the value of its shoots and timber and an increase in affiliated labor and production costs, many of these stands have been abandoned, resulting in the occurrence of vegetation succession. Currently, our understanding on changes in soil microbial stoichiometric and entropic effects and associated imbalances following stand abandonment is limited. Accordingly, this study explores three timescales of Ph. edulis stand abandonment (i.e., 0, 9, and 21 years) to investigate soil-microbial carbon (C), nitrogen (N), and phosphorus (P) dynamics within a 30 cm soil profile. Results showed that (1) following abandonment, vegetation succession significantly influenced soil carbon (Csoil), nitrogen (Nsoil), and phosphorus (Psoil), microbial biomass (Cmic), nitrogen (Nmic), and phosphorus (Pmic), and Csoil:Nsoil:Psoil and Cmic:Nmic:Pmic ratios. Additionally, Csoil, Nsoil, Psoil, Cmic, Nmic, Pmic all increased significantly over time following abandonment. Moreover, Csoil:Nsoil, Cmic:Pmic, and Nmic:Pmic ratios clearly increased while Csoil:Psoil, Nsoil:Psoil, and Cmic:Nmic ratios all significantly decreased. (2) Soil microbial entropy nitrogen (qMBN) and soil microbial imbalances in Cimb:Nimb increased while soil microbial entropy carbon (qMBC), soil microbial entropy phosphorus (qMBP), and soil microbial imbalances in Cimb:Pimb and Nimb:Pimb decreased over time following abandonment. (3) Redundancy analysis (RDA) indicated that Csoil:Nsoil and Cmic:Pmic ratios were key influencing factors of microbial quotient (qMB), explaining 55.35 % and 24.39 % of variation, respectively. Following abandonment, positive or negative successional impacts on Csoil:Nsoil:Psoil, microbial C, N, P stoichiometric imbalances (Cimb:Nimb:Pimb), and Csoil:Nsoil:Psoil ratios had a positive effect on qMB. Collectively, these findings highlight the importance of Csoil:Nsoil:Psoil and Cimb:Nimb:Pimb ratios in regulating qMB induced by vegetation succession following Ph. edulis abandonment, and provide valuable information for vegetation restoration and establishment of bamboo mixed forest.
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Affiliation(s)
- Yanyan Xie
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, Zhejiang, China
| | - Wei Zhang
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, Zhejiang, China
| | - Ziwu Guo
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, Zhejiang, China.
| | - Xuhua Du
- China National Bamboo Research Center, Hangzhou 310012, Zhejiang, China
| | - Lili Fan
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, Zhejiang, China
| | - Shuanglin Chen
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, Zhejiang, China
| | - Yawen Dong
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, Zhejiang, China
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Poppeliers SWM, Hefting M, Dorrepaal E, Weedon JT. Functional microbial ecology in arctic soils: the need for a year-round perspective. FEMS Microbiol Ecol 2022; 98:6824434. [PMID: 36368693 PMCID: PMC9701097 DOI: 10.1093/femsec/fiac134] [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: 03/31/2022] [Revised: 11/01/2022] [Accepted: 11/09/2022] [Indexed: 11/13/2022] Open
Abstract
The microbial ecology of arctic and sub-arctic soils is an important aspect of the global carbon cycle, due to the sensitivity of the large soil carbon stocks to ongoing climate warming. These regions are characterized by strong climatic seasonality, but the emphasis of most studies on the short vegetation growing season could potentially limit our ability to predict year-round ecosystem functions. We compiled a database of studies from arctic, subarctic, and boreal environments that include sampling of microbial community and functions outside the growing season. We found that for studies comparing across seasons, in most environments, microbial biomass and community composition vary intra-annually, with the spring thaw period often identified by researchers as the most dynamic time of year. This seasonality of microbial communities will have consequences for predictions of ecosystem function under climate change if it results in: seasonality in process kinetics of microbe-mediated functions; intra-annual variation in the importance of different (a)biotic drivers; and/or potential temporal asynchrony between climate change-related perturbations and their corresponding effects. Future research should focus on (i) sampling throughout the entire year; (ii) linking these multi-season measures of microbial community composition with corresponding functional or physiological measurements to elucidate the temporal dynamics of the links between them; and (iii) identifying dominant biotic and abiotic drivers of intra-annual variation in different ecological contexts.
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Affiliation(s)
- Sanne W M Poppeliers
- Corresponding author: Department of Biology, Utrecht University, 3584 CH, The Netherlands. E-mail:
| | - Mariet Hefting
- Department of Biology, Utrecht University, 3584 CH, The Netherlands
| | - Ellen Dorrepaal
- Climate Impacts Research Centre, Umea University, SE-981 07, Abisko, Sweden
| | - James T Weedon
- Department of Ecological Science, Vrije Universiteit Amsterdam, 1081 HV, Amsterdam, The Netherlands
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MacTavish R, Anderson JT. Water and nutrient availability exert selection on reproductive phenology. AMERICAN JOURNAL OF BOTANY 2022; 109:1702-1716. [PMID: 36031862 DOI: 10.1002/ajb2.16057] [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: 01/25/2022] [Revised: 07/22/2022] [Accepted: 07/22/2022] [Indexed: 06/15/2023]
Abstract
PREMISE Global change has changed resource availability to plants, which could shift the adaptive landscape. We hypothesize that novel water and nutrient availability combinations alter patterns of natural selection on reproductive phenology in Boechera stricta (Brassicaceae) and influence the evolution of local adaptation. METHODS We conducted a multifactorial greenhouse study using 35 accessions of B. stricta sourced from a broad elevational gradient in the Rocky Mountains. We exposed full siblings to three soil water and two nutrient availability treatment levels, reflecting current and projected future conditions. In addition, we quantified fitness (seed count) and four phenological traits: the timing of first flowering, the duration of flowering, and height and leaf number at flowering. RESULTS Selection favored early flowering and longer duration of flowering, and the genetic correlation between these traits accorded with the direction of selection. In most treatments, we found selection for increased height, but selection on leaf number depended on water availability, with selection favoring more leaves in well-watered conditions and fewer leaves under severe drought. Low-elevation genotypes had the greatest fitness under drought stress, consistent with local adaptation. CONCLUSIONS We found evidence of strong selection on these heritable traits. Furthermore, the direction and strength of selection on size at flowering depended on the variable measured (height vs. leaf number). Finally, selection often favored both early flowering and a longer duration of flowering. Selection on these two components of phenology can be difficult to disentangle due to tight genetic correlations.
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Affiliation(s)
- Rachel MacTavish
- Department of Genetics and Odum School of Ecology, University of Georgia, Athens, GA, 30602, USA
| | - Jill T Anderson
- Department of Genetics and Odum School of Ecology, University of Georgia, Athens, GA, 30602, USA
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Kaštovská E, Choma M, Čapek P, Kaňa J, Tahovská K, Kopáček J. Soil warming during winter period enhanced soil N and P availability and leaching in alpine grasslands: A transplant study. PLoS One 2022; 17:e0272143. [PMID: 35917373 PMCID: PMC9345486 DOI: 10.1371/journal.pone.0272143] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 07/13/2022] [Indexed: 11/19/2022] Open
Abstract
Alpine meadows are strongly affected by climate change. Increasing air temperature prolongs the growing season and together with changing precipitation patterns alters soil temperature during winter. To estimate the effect of climate change on soil nutrient cycling, we conducted a field experiment. We transferred undisturbed plant-soil mesocosms from two wind-exposed alpine meadows at ~2100 m a.s.l. to more sheltered plots, situated ~300–400 m lower in the same valleys. The annual mean air temperature was 2°C higher at the lower plots and soils that were normally frozen at the original plots throughout winters were warmed to ~0°C due to the insulation provided by continuous snow cover. After two years of exposure, we analyzed the nutrient content in plants, and changes in soil bacterial community, decomposition, mineralization, and nutrient availability. Leaching of N and P from the soils was continuously measured using ion-exchange resin traps. Warming of soils to ~0°C during the winter allowed the microorganisms to remain active, their metabolic processes were not restricted by soil freezing. This change accelerated nutrient cycling, as evidenced by increased soil N and P availability, their higher levels in plants, and elevated leaching. In addition, root exudation and preferential enzymatic mining of P over C increased. However, any significant changes in microbial biomass, bacterial community composition, decomposition rates, and mineralization during the growing season were not observed, suggesting considerable structural and functional resilience of the microbial community. In summary, our data suggest that changes in soil temperature and snow cover duration during winter periods are critical for altering microbially-mediated processes (even at unchanged soil microbial community and biomass) and may enhance nutrient availability in alpine meadows. Consequently, ongoing climate change, which leads to soil warming and decreasing snow insulation, has a potential to significantly alter nutrient cycling in alpine and subalpine meadows compared to the current situation and increase the year-on-year variability in nutrient availability and leaching.
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Affiliation(s)
- Eva Kaštovská
- Faculty of Science, Department of Ecosystem Biology, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
- * E-mail:
| | - Michal Choma
- Faculty of Science, Department of Ecosystem Biology, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
| | - Petr Čapek
- Faculty of Science, Department of Ecosystem Biology, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
| | - Jiří Kaňa
- Faculty of Science, Department of Ecosystem Biology, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
- Biology Centre of the Czech Academy of Sciences, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Karolina Tahovská
- Faculty of Science, Department of Ecosystem Biology, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
| | - Jiří Kopáček
- Biology Centre of the Czech Academy of Sciences, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
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Yang Y, Shi G, Liu Y, Ma L, Zhang Z, Jiang S, Pan J, Zhang Q, Yao B, Zhou H, Feng H. Experimental Warming Has Not Affected the Changes in Soil Organic Carbon During the Growing Season in an Alpine Meadow Ecosystem on the Qinghai-Tibet Plateau. FRONTIERS IN PLANT SCIENCE 2022; 13:847680. [PMID: 35371126 PMCID: PMC8971846 DOI: 10.3389/fpls.2022.847680] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 02/23/2022] [Indexed: 06/14/2023]
Abstract
The effects of climate warming and season on soil organic carbon (SOC) have received widespread attention, but how climate warming affects the seasonal changes of SOC remains unclear. Here, we established a gradient warming experiment to investigate plant attributes and soil physicochemical and microbial properties that were potentially associated with changes in SOC at the beginning (May) and end (August) of the growing season in an alpine meadow ecosystem on the Qinghai-Tibet Plateau. The SOC of August was lower than that of May, and the storage of SOC in August decreased by an average of 18.53 million grams of carbon per hectare. Warming not only failed to alter the content of SOC regardless of the season but also did not affect the change in SOC during the growing season. Among all the variables measured, microbial biomass carbon was highly coupled to the change in SOC. These findings indicate that alpine meadow soil is a source of carbon during the growing season, but climate warming has no significant impact on it. This study highlights that in the regulation of carbon source or pool in alpine meadow ecosystem, more attention should be paid to changes in SOC during the growing season, rather than climate warming.
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Affiliation(s)
- Yue Yang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Guoxi Shi
- Key Laboratory of Utilization of Agriculture Solid Waste Resources in Gansu Province, College of Bioengineering and Biotechnology, Tianshui Normal University, Tianshui, China
- Key Laboratory of Restoration Ecology of Cold Area in Qinghai Province, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
| | - Yongjun Liu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Li Ma
- Key Laboratory of Restoration Ecology of Cold Area in Qinghai Province, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
| | - Zhonghua Zhang
- Key Laboratory of Restoration Ecology of Cold Area in Qinghai Province, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
| | - Shengjing Jiang
- State Key Laboratory of Grassland and Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
| | - Jianbin Pan
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Qi Zhang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Buqing Yao
- Key Laboratory of Utilization of Agriculture Solid Waste Resources in Gansu Province, College of Bioengineering and Biotechnology, Tianshui Normal University, Tianshui, China
| | - Huakun Zhou
- Key Laboratory of Restoration Ecology of Cold Area in Qinghai Province, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
| | - Huyuan Feng
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
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10
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Yin B, Li J, Zhang Q, Wu N, Zhang J, Rong X, Tao Y, Zang Y, Li Y, Zhou X, Zhang Y. Freeze-thaw cycles change the physiological sensitivity of Syntrichia caninervis to snow cover. JOURNAL OF PLANT PHYSIOLOGY 2021; 266:153528. [PMID: 34563792 DOI: 10.1016/j.jplph.2021.153528] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 09/14/2021] [Accepted: 09/15/2021] [Indexed: 06/13/2023]
Abstract
Spring, especially the freeze-thaw season, is considered the key period for the growth and carbon sequestration of desert mosses. It is not clear how the change in environment water and temperature affects the physiological characteristics of desert mosses in freeze-thaw season. In this study, the effects of water and freeze-thaw cycles on the physiological characteristics of Syntrichia caninervis were assessed by manipulating the increase or removal of 65% snow and changes in the freeze-thaw cycles. The results showed that the changes in snow depth, freeze-thaw cycles, and their interaction significantly affected the plant water content, osmoregulatory substances content, antioxidant substance, and antioxidant enzyme activities. The contents of free proline, soluble sugar, ascorbic acid (AsA), reduced glutathione (GSH), and malondialdehyde (MDA), and superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities increased significantly with the decrease in snow depth and freeze-thaw cycles. POD and free proline were the most sensitive to the snow depth and freeze-thaw cycles, while SOD and CAT were the least sensitive. Therefore, compared with the increase in freeze-thaw cycles, the reduction in freeze-thaw cycles weakened the physiological sensitivity of S. caninervis to snow depth changes.
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Affiliation(s)
- Benfeng Yin
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 830011, Urumqi, China
| | - Jiwen Li
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 830011, Urumqi, China; College of Life Science and Technology, Xinjiang University, Urumqi, 830064, China
| | - Qing Zhang
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 830011, Urumqi, China; Geography Science College, Shanxi Normal University, Linfen, Shanxi Province, 041000, China
| | - Nan Wu
- Yantai Key Laboratory of Coastal Hydrological Processes and Environmental Security, Ludong University, Yantai, Shandong, 264025, China
| | - Jing Zhang
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 830011, Urumqi, China
| | - Xiaoying Rong
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 830011, Urumqi, China
| | - Ye Tao
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 830011, Urumqi, China
| | - Yongxin Zang
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 830011, Urumqi, China
| | - Yonggang Li
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 830011, Urumqi, China
| | - Xiaobing Zhou
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 830011, Urumqi, China.
| | - Yuanming Zhang
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 830011, Urumqi, China.
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11
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Gao D, Liu Z, Bai E. Effects of in situ freeze-thaw cycles on winter soil respiration in mid-temperate plantation forests. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 793:148567. [PMID: 34175599 DOI: 10.1016/j.scitotenv.2021.148567] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 05/30/2021] [Accepted: 06/16/2021] [Indexed: 06/13/2023]
Abstract
As an important factor regulating soil carbon cycle, freeze-thaw cycle significantly affects winter soil respiration in temperate regions. However, few in situ studies have been carried out to evaluate the effect of freeze-thaw cycle on soil respiration. Here, a field experiment was conducted to explore the response of winter soil respiration to freeze-thaw cycle and the underlying mechanisms in larch and Chinese pine plantation forests in a mid-temperate region. These results indicated that CO2 emissions during the freeze-thaw period accounted for 18.89-18.94% and 0.79-1.00% of the cumulative winter CO2 emissions and the annual soil CO2 emissions, respectively. Soil respiration rates during the thawing phase were 1.54-3.95 times higher than those during the freezing phase, which was mainly due to the increase of soil microbial biomass upon thawing. This effect declined during the second freeze-thaw cycle compared to the first freeze-thaw cycle due to the exhaustion of resources for microbes. The different responses of soil CO2 flux to freeze-thaw cycle between the two types of forests were mainly because of the difference in the thickness of litter layer, which plays an important role in regulating soil temperature and enzyme activity. These results suggest the intensity and frequency of freeze-thaw cycle strongly affect soil carbon emissions during the freeze-thaw cycle period. Therefore, these factors should be considered in laboratory studies and model simulations under climate change scenarios.
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Affiliation(s)
- Decai Gao
- Key Laboratory of Geographical Processes and Ecological Security of Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, Changchun 130024, China
| | - Ziping Liu
- Key Laboratory of Geographical Processes and Ecological Security of Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, Changchun 130024, China.
| | - Edith Bai
- Key Laboratory of Geographical Processes and Ecological Security of Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, Changchun 130024, China; Key Laboratory of Vegetation Ecology, Ministry of Education, Northeast Normal University, Changchun 130024, China.
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12
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Hamann E, Denney D, Day S, Lombardi E, Jameel MI, MacTavish R, Anderson JT. Review: Plant eco-evolutionary responses to climate change: Emerging directions. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 304:110737. [PMID: 33568289 DOI: 10.1016/j.plantsci.2020.110737] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 10/23/2020] [Accepted: 10/25/2020] [Indexed: 05/14/2023]
Abstract
Contemporary climate change is exposing plant populations to novel combinations of temperatures, drought stress, [CO2] and other abiotic and biotic conditions. These changes are rapidly disrupting the evolutionary dynamics of plants. Despite the multifactorial nature of climate change, most studies typically manipulate only one climatic factor. In this opinion piece, we explore how climate change factors interact with each other and with biotic pressures to alter evolutionary processes. We evaluate the ramifications of climate change across life history stages,and examine how mating system variation influences population persistence under rapid environmental change. Furthermore, we discuss how spatial and temporal mismatches between plants and their mutualists and antagonists could affect adaptive responses to climate change. For example, plant-virus interactions vary from highly pathogenic to mildly facilitative, and are partly mediated by temperature, moisture availability and [CO2]. Will host plants exposed to novel, stressful abiotic conditions be more susceptible to viral pathogens? Finally, we propose novel experimental approaches that could illuminate how plants will cope with unprecedented global change, such as resurrection studies combined with experimental evolution, genomics or epigenetics.
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Affiliation(s)
- Elena Hamann
- Department of Genetics and Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
| | - Derek Denney
- Department of Genetics and Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
| | - Samantha Day
- Department of Genetics and Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
| | - Elizabeth Lombardi
- Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14850, USA
| | - M Inam Jameel
- Department of Genetics and Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
| | - Rachel MacTavish
- Department of Genetics and Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
| | - Jill T Anderson
- Department of Genetics and Odum School of Ecology, University of Georgia, Athens, GA 30602, USA.
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13
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Broadbent AAD, Snell HSK, Michas A, Pritchard WJ, Newbold L, Cordero I, Goodall T, Schallhart N, Kaufmann R, Griffiths RI, Schloter M, Bahn M, Bardgett RD. Climate change alters temporal dynamics of alpine soil microbial functioning and biogeochemical cycling via earlier snowmelt. ISME JOURNAL 2021; 15:2264-2275. [PMID: 33619353 DOI: 10.1038/s41396-021-00922-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 01/26/2021] [Accepted: 02/01/2021] [Indexed: 12/30/2022]
Abstract
Soil microbial communities regulate global biogeochemical cycles and respond rapidly to changing environmental conditions. However, understanding how soil microbial communities respond to climate change, and how this influences biogeochemical cycles, remains a major challenge. This is especially pertinent in alpine regions where climate change is taking place at double the rate of the global average, with large reductions in snow cover and earlier spring snowmelt expected as a consequence. Here, we show that spring snowmelt triggers an abrupt transition in the composition of soil microbial communities of alpine grassland that is closely linked to shifts in soil microbial functioning and biogeochemical pools and fluxes. Further, by experimentally manipulating snow cover we show that this abrupt seasonal transition in wide-ranging microbial and biogeochemical soil properties is advanced by earlier snowmelt. Preceding winter conditions did not change the processes that take place during snowmelt. Our findings emphasise the importance of seasonal dynamics for soil microbial communities and the biogeochemical cycles that they regulate. Moreover, our findings suggest that earlier spring snowmelt due to climate change will have far reaching consequences for microbial communities and nutrient cycling in these globally widespread alpine ecosystems.
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Affiliation(s)
- Arthur A D Broadbent
- Department of Earth and Environmental Sciences, Michael Smith Building, The University of Manchester, Oxford Road, Manchester, M13 9PT, UK.
| | - Helen S K Snell
- Department of Earth and Environmental Sciences, Michael Smith Building, The University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - Antonios Michas
- Research Unit for Comparative Microbiome Analysis, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany.,Chair for Soil Science, Technical University of Munich, Emil-Ramann-Str 2, 85354, Freising, Germany
| | - William J Pritchard
- Department of Earth and Environmental Sciences, Michael Smith Building, The University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - Lindsay Newbold
- UK Centre for Ecology & Hydrology, Maclean Building, Benson Lane, Crowmarsh Gifford, Wallingford, Oxfordshire, OX10 8BB, UK
| | - Irene Cordero
- Department of Earth and Environmental Sciences, Michael Smith Building, The University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - Tim Goodall
- UK Centre for Ecology & Hydrology, Maclean Building, Benson Lane, Crowmarsh Gifford, Wallingford, Oxfordshire, OX10 8BB, UK
| | - Nikolaus Schallhart
- Faculty of Biology, University of Innsbruck, Sternwartestr. 15, Innsbruck, Austria
| | - Ruediger Kaufmann
- Department of Ecology, University of Innsbruck, Technikerstr. 25, Innsbruck, Austria
| | - Robert I Griffiths
- UK Centre for Ecology & Hydrology, Environment Centre Wales, Deiniol Road, Bangor, Gwynedd, LL57 2UW, UK
| | - Michael Schloter
- Research Unit for Comparative Microbiome Analysis, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany.,Chair for Soil Science, Technical University of Munich, Emil-Ramann-Str 2, 85354, Freising, Germany
| | - Michael Bahn
- Department of Ecology, University of Innsbruck, Sternwartestr. 15, Innsbruck, Austria
| | - Richard D Bardgett
- Department of Earth and Environmental Sciences, Michael Smith Building, The University of Manchester, Oxford Road, Manchester, M13 9PT, UK
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14
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Yang F, Ni X, Zeng X, Li H, Tan B, Liang Z, Liu B, Xu Z, Zhang J. Short-term winter snow reduction stimulates soil nutrient leaching without changing the microbial biomass in an alpine fir forest. Glob Ecol Conserv 2021. [DOI: 10.1016/j.gecco.2020.e01434] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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15
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Reed CC, Merrill AG, Drew WM, Christman B, Hutchinson RA, Keszey L, Odell M, Swanson S, Verburg PSJ, Wilcox J, Hart SC, Sullivan BW. Montane Meadows: A Soil Carbon Sink or Source? Ecosystems 2020. [DOI: 10.1007/s10021-020-00572-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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16
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Ren Y, Zhang L, Yang K, Li Z, Yin R, Tan B, Wang L, Liu Y, Li H, You C, Liu S, Xu Z, Kardol P. Short-term effects of snow cover manipulation on soil bacterial diversity and community composition. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 741:140454. [PMID: 32610243 DOI: 10.1016/j.scitotenv.2020.140454] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 06/18/2020] [Accepted: 06/21/2020] [Indexed: 06/11/2023]
Abstract
Winter snow cover is a major driver of soil microbial processes in high-latitude and high-altitude ecosystems. Warming-induced reduction in snow cover as predicted under future climate scenarios may shift soil bacterial communities with consequences for soil carbon and nutrient cycling. The underlying mechanisms, however, remain elusive. In the present study, we conducted a snow manipulation experiment in a Tibetan spruce forest to explore the immediate and intra-annual legacy effects of snow exclusion on soil bacterial communities. We analyzed bacterial diversity and community composition in the winter (i.e., the deep snow season), in the transitional thawing period, and in the middle of the growing season. Proteobacteria, Acidobacteria, and Actinobacteria were dominant phyla across the seasons and snow regimes. Bacterial diversity was generally not particularly sensitive to the absence of snow cover. However, snow exclusion positively affected Simpson diversity in the winter but not in the thawing period and the growing season. Bacterial diversity further tended to be higher in winter than in the growing season. In the winter, the taxonomic composition shifted in response to snow exclusion, while composition did not differ between exclusion and control plots in the thawing period and the growing season. Soil bacterial communities strongly varied across seasons, and the variations differed in specific groups. Both soil climatic factors (i.e., temperature and moisture) and soil biochemical variables partly accounted for the seasonal dynamics of bacterial communities. Taken together, our study indicates that soil bacterial communities in Tibetan forests are rather resilient to change in snow cover, at least at an intra-annual scale.
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Affiliation(s)
- Yuzhi Ren
- Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province & National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River & Rainy Area of West China Plantation Ecosystem Permanent Scientific Research Base & Institute of Ecology & Forestry, Sichuan Agricultural University, Chengdu 611130, China
| | - Li Zhang
- Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province & National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River & Rainy Area of West China Plantation Ecosystem Permanent Scientific Research Base & Institute of Ecology & Forestry, Sichuan Agricultural University, Chengdu 611130, China
| | - Kaijun Yang
- Global Ecology Unit CREAF-CSIC-UAB, CSIC, Barcelona, Catalonia, Spain
| | - Zhijie Li
- Forschungszentrum Jülich GmbH, Agrosphere (IBG-3), Jülich, Germany
| | - Rui Yin
- Helmholtz-Centre for Environmental Research-UFZ, Department of Community Ecology, Theodor-Lieser-Strasse 4, 06110 Halle (Saale), Germany; Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, 901-83 Umeå, Sweden
| | - Bo Tan
- Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province & National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River & Rainy Area of West China Plantation Ecosystem Permanent Scientific Research Base & Institute of Ecology & Forestry, Sichuan Agricultural University, Chengdu 611130, China
| | - Lixia Wang
- Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province & National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River & Rainy Area of West China Plantation Ecosystem Permanent Scientific Research Base & Institute of Ecology & Forestry, Sichuan Agricultural University, Chengdu 611130, China
| | - Yang Liu
- Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province & National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River & Rainy Area of West China Plantation Ecosystem Permanent Scientific Research Base & Institute of Ecology & Forestry, Sichuan Agricultural University, Chengdu 611130, China
| | - Han Li
- Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province & National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River & Rainy Area of West China Plantation Ecosystem Permanent Scientific Research Base & Institute of Ecology & Forestry, Sichuan Agricultural University, Chengdu 611130, China
| | - Chengming You
- Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province & National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River & Rainy Area of West China Plantation Ecosystem Permanent Scientific Research Base & Institute of Ecology & Forestry, Sichuan Agricultural University, Chengdu 611130, China
| | - Sining Liu
- Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province & National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River & Rainy Area of West China Plantation Ecosystem Permanent Scientific Research Base & Institute of Ecology & Forestry, Sichuan Agricultural University, Chengdu 611130, China
| | - Zhenfeng Xu
- Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province & National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River & Rainy Area of West China Plantation Ecosystem Permanent Scientific Research Base & Institute of Ecology & Forestry, Sichuan Agricultural University, Chengdu 611130, China.
| | - Paul Kardol
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, 901-83 Umeå, Sweden
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17
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Hamamoto T, Uchida Y, von Rein I, Mukumbuta I. Effects of short-term freezing on nitrous oxide emissions and enzyme activities in a grazed pasture soil after bovine-urine application. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 740:140006. [PMID: 32563873 DOI: 10.1016/j.scitotenv.2020.140006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/30/2020] [Accepted: 06/03/2020] [Indexed: 06/11/2023]
Abstract
Nitrous oxide (N2O) emissions from soils applied with livestock excreta have been widely reported previously. The highest N2O emissions from soils are also often reported during thawing periods in cold regions where soil freezing is common. However, the combined effects of cow urine application and freeze-thaw events on N2O emissions and the related enzyme activities are still not clear. Thus, we simulated a freeze-thaw event at -3 °C for 7 days, and then increased to 3 °C for 46 days using intact soil cores with cow urine (392 kg N ha-1). We compared the factors influencing the magnitudes of N2O emissions through soil microbial processes with and without the freeze-thaw event. Dicyandiamide (DCD), an inhibitor of nitrification, was added to investigate the significance of nitrification on N2O emissions. The N2O emission rates from the urine-applied soils peaked to approximately 1000 μg N2O-N m-2 h-1 immediately after the soils thawed. Soil freezing with urine application was significantly higher cumulative N2O emissions (537 mg N2O-N m-2), compared to non-frozen soils with urine (247 mg N2O-N m-2) during the incubation period (54 days). The effect of DCD application on N2O emissions was not clear during the freeze-thaw event, although nitrate production rates were reduced. After the freezing event, soil moisture (water-filled pore space) was significantly higher in the non-frozen soils compared to the frozen soils, due to a 9% decline in bulk density of frozen soils. Additionally, the impact of thawing on urease and denitrification enzyme activities was influenced by the urine application. Urine application increased the urease activity, while the freezing event decreased the magnitudes. The physical changes in the soils were also important controlling factors of the N2O emissions from cow urine-applied soils in cold regions.
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Affiliation(s)
- Toru Hamamoto
- Graduate School of Agriculture, Hokkaido University, Kita 9 Nishi 9 Kita-Ku, Sapporo, Hokkaido 060-8589, Japan; Arid Land Research Center, Tottori University, 1390 Hamasaka, Tottori, Tottori 680-0001, Japan
| | - Yoshitaka Uchida
- Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9 Kita-Ku, Sapporo, Hokkaido 060-8589, Japan.
| | - Isabell von Rein
- Department of Soil and Water Systems, University of Idaho, 875 Perimeter Drive, Moscow, ID 83844, USA
| | - Ikabongo Mukumbuta
- Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9 Kita-Ku, Sapporo, Hokkaido 060-8589, Japan
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18
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Boswell EP, Thompson AM, Balster NJ, Bajcz AW. Novel determination of effective freeze-thaw cycles as drivers of ecosystem change. JOURNAL OF ENVIRONMENTAL QUALITY 2020; 49:314-323. [PMID: 33016430 DOI: 10.1002/jeq2.20053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 01/16/2020] [Indexed: 06/11/2023]
Abstract
Soil freeze-thaw cycles (FTCs) profoundly influence biophysical conditions and modify biogeochemical processes across many northern-hemisphere and alpine ecosystems. How FTCs will contribute to global processes in seasonally snow-covered ecosystems in the future is of particular importance as climate change progresses and winter snowpacks decline. Our understanding of these contributions is limited because there has been little consideration of inter- and intrayear variability in the characteristics of FTCs, in part due to a limited appreciation for which of these characteristics matters most with respect to a given biogeochemical process. Here, we introduce the concept of effective FTCs: those that are most likely linked to changes in key soil processes. We also propose a set of parameters to quantify and characterize effective FTCs using standard field soil temperature data. To put these proposed parameters into effective practice, we present FTCQuant, an R package of functions that quantifies FTCs based on a set of user-defined parameter criteria and, importantly, summarizes the individual characteristics of each FTC counted. To demonstrate the utility of these new concepts and tools, we applied the FTCQuant package to re-analyze data from two published studies to help explain over-winter changes to N2 O emissions and wet-aggregate stability. We found that effective FTCs would be defined differently for each of these response variables and that effective FTCs provided a 76 and 33% increase in model fit for wet-aggregate stability and cumulative N2 O emission, respectively, relative to conventional FTC quantification methods focusing on fluctuations around 0 °C. These results demonstrate the importance of identifying effective FTCs when scaling soil processes to regional or global levels. We hope our contributions will inform future deductions, hypothesis generation, and experimentation with respect to expected changes in freeze-thaw cycling globally.
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Affiliation(s)
- Edward P Boswell
- Dep. of Soil Science, Univ. of Wisconsin-Madison, 1525 Observatory Dr., Madison, WI, 53706, USA
| | - Anita M Thompson
- Dep. of Biological Systems Engineering, Univ. of Wisconsin-Madison, 460 Henry Mall, Madison, WI, 53706, USA
| | - Nick J Balster
- Dep. of Soil Science, Univ. of Wisconsin-Madison, 1525 Observatory Dr., Madison, WI, 53706, USA
| | - Alex W Bajcz
- Dep. of Biology, Drew Univ., 36 Madison Ave., Madison, NJ, 07940, USA
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19
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An Automated Method for Surface Ice/Snow Mapping Based on Objects and Pixels from Landsat Imagery in a Mountainous Region. REMOTE SENSING 2020. [DOI: 10.3390/rs12030485] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Surface ice/snow is a vital resource and is sensitive to climate change in many parts of the world. The accurate and timely measurement of the spatial distribution of ice/snow is critical for managing water resources. Object-oriented and pixel-oriented methods often have some limitations due to the image segmentation scale, the determination of the optimal threshold and background heterogeneity. Therefore, this study proposes a method for automatically extracting large-scale surface ice/snow from Landsat series images, which takes advantage of the combination of image segmentation, the watershed algorithm and a series of ice/snow indices. We tested our novel method in three different regions in the Karakoram Mountains, and the experimental results show that the produced ice/snow map obtained a user’s accuracy greater than 90%, a producer’s accuracy greater than 97%, an overall accuracy greater than 98% and a kappa coefficient greater than 0.93. Comparing the extraction results under segmentation scales of 10, 15, 20 and 25, the user’s accuracy and producer’s accuracy from the proposed method are very similar, which indicates that the proposed method is more reliable and stable for extracting ice/snow objects than the object-oriented method. Due to the different reflectivity values in the near-infrared band in the snow and water categories, the normalized difference forest snow index (NDFSI) is suitable for Landsat TM and ETM+ images. This study can serve as a reliable, scientific reference for rapidly and accurately extracting ice/snow objects.
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20
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MacTavish R, Anderson JT. Resource availability alters fitness trade-offs: implications for evolution in stressful environments. AMERICAN JOURNAL OF BOTANY 2020; 107:308-318. [PMID: 31943133 DOI: 10.1002/ajb2.1417] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 09/16/2019] [Indexed: 05/22/2023]
Abstract
PREMISE Industrialization and human activities have elevated temperatures and caused novel precipitation patterns, altering soil moisture and nutrient availability. Predicting evolutionary responses to climate change requires information on the agents of selection that drive local adaptation and influence resource acquisition and allocation. Here, we examined the contribution of nutrient and drought stress to local adaptation, and we tested whether trade-offs across fitness components constrain or facilitate adaptation under resource stress. METHODS We exposed 35 families of Boechera stricta (Brassicaceae) to three levels of water and two levels of nutrient supply in a factorial design in the greenhouse. We sourced maternal families from a broad elevational gradient (2499-3530 m a.s.l.), representing disparate soil moisture and nutrient availability. RESULTS Concordant with local adaptation, maternal families from arid, low-elevation populations had enhanced fecundity under severe drought over those from more mesic, high-elevation sites. Furthermore, fitness trade-offs between growth and reproductive success depended on the environmental context. Under high, but not low, nutrient levels, we found a negative phenotypic relationship between the probability of reproduction and growth rate. Similarly, a negative phenotypic association only emerged between fecundity and growth under severe drought stress, not the benign water treatment levels, indicating that stressful resource environments alter the direction of trait correlations. Genetic covariances were broadly concordant with these phenotypic patterns. CONCLUSIONS Despite high heritabilities in all fitness components across treatments, trade-offs between growth and reproduction could constrain adaptation to increasing drought stress and novel nutrient levels.
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Affiliation(s)
- Rachel MacTavish
- Department of Genetics and Odum School of Ecology, University of Georgia, Athens, GA, USA
| | - Jill T Anderson
- Department of Genetics and Odum School of Ecology, University of Georgia, Athens, GA, USA
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Yan Y, Yan R, Wang X, Xu X, Xu D, Jin D, Chen J, Xin X. Grazing affects snow accumulation and subsequent spring soil water by removing vegetation in a temperate grassland. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 697:134189. [PMID: 31491640 DOI: 10.1016/j.scitotenv.2019.134189] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 07/17/2019] [Accepted: 08/28/2019] [Indexed: 06/10/2023]
Abstract
By altering plant and soil properties and microclimate environments, grazing has a profound influence on the structure and function of grassland ecosystems. However, few studies have addressed the potential grazing effects on snow accumulation and subsequent spring soil water after snow melting and soil thawing. In this study, vegetation properties, snow accumulation and soil water were measured in experimental plots subjected to 8 years of cattle grazing comprising six different grazing intensity treatments in a typical temperate grassland in eastern Eurasia. The results indicated that heavy grazing reduced the snow depth by 51% and the snow mass by 40%. Snow accumulation first rapidly increased but then remained relatively stable with increases in both the aboveground biomass and canopy height. An obvious inflection point occurred at approximately 200 g m-2 aboveground biomass and at a 12.5 cm canopy height. The obvious difference in soil water content between the heavily grazed and ungrazed treatments occurred mainly in the spring after snow melting and soil thawing. The spring soil water content (0-30 cm) reached 31.5% in the ungrazed treatment (G0), which was 1.7 times that in the heavily grazed treatment (G0.92). The soil water content increased exponentially with increasing vegetation properties (aboveground biomass, canopy height and canopy cover), and a similar trend occurred with increasing snow mass and snow depth. Our structural equation modeling showed that both vegetation properties and snow accumulation had significant positive effects on spring soil water. By removing vegetation, grazing at increased intensities had significant, indirect suppressive effects on snow accumulation and spring soil water. Therefore, to obtain increased amounts of snow accumulation and spring soil water, land managers should consider reducing the grazing intensity or leaving some plots ungrazed.
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Affiliation(s)
- Yuchun Yan
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Ruirui Yan
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Xu Wang
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Xingliang Xu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy Sciences, 11A, Datun Road, Chaoyang District, Beijing 100101, China
| | - Dawei Xu
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Dongyan Jin
- Agricultural Information Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Jinqiang Chen
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Xiaoping Xin
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
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Küttim M, Laine AM, Küttim L, Ilomets M, Robroek BJM. Winter climate change increases physiological stress in calcareous fen bryophytes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 695:133867. [PMID: 31421346 DOI: 10.1016/j.scitotenv.2019.133867] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 08/08/2019] [Accepted: 08/09/2019] [Indexed: 06/10/2023]
Abstract
Calcareous spring fens are among the rarest and most endangered wetland types worldwide. The majority of these ecosystems can be found at high latitudes, where they are affected by above average rates of climate change. Particularly winter temperatures are increasing, which results in decreased snow cover. As snow provides an insulating layer that protects ecosystems from subzero temperatures, its decrease is likely to induce stress to plants. To investigate the sensitivity of the bryophyte community - key to the functioning of calcareous spring fens - to changing climatic conditions, we studied the annual variation in ecophysiology of two dominant bryophytes: Campylium stellatum and Scorpidium scorpioides. Further, a snow removal experiment was used to simulate the effect of changing winter conditions. In both species, we observed lowest efficiency of photosystem II (Fv/Fm) in spring, indicating physiological stress, and highest chlorophyll-a, -b and carotenoid concentrations in autumn. Snow removal exacerbated physiological stress in bryophytes. Consequently Fv/Fm, pigment concentrations and chlorophyll to carotenoids ratios declined, while chlorophyll-a to -b ratios increased. Moreover, these effects of winter climate change cascaded to the growing season. C. stellatum, a low hummock inhabitor, suffered more from snow removal (annual mean decline in Fv/Fm 7.7% and 30.0% in chlorophyll-a) than S. scorpioides, a hollow species (declines 5.4% and 14.5%, respectively). Taken together, our results indicate that spring fen bryophytes are negatively impacted by winter climate change, as a result of longer frost periods and increased numbers of freeze-thaw cycles in combination with higher light intensity and dehydration.
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Affiliation(s)
- Martin Küttim
- Tallinn University, School of Natural Sciences and Health, Institute of Ecology, Uus-Sadama 5, 10120 Tallinn, Estonia.
| | - Anna M Laine
- University of Oulu, Department of Ecology and Genetics, P.O.Box 8000, FI-90014 Oulu, Finland; University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland
| | - Liisa Küttim
- Tallinn University, School of Natural Sciences and Health, Institute of Ecology, Uus-Sadama 5, 10120 Tallinn, Estonia
| | - Mati Ilomets
- Tallinn University, School of Natural Sciences and Health, Institute of Ecology, Uus-Sadama 5, 10120 Tallinn, Estonia
| | - Bjorn J M Robroek
- University of Southampton, Faculty of Natural and Environmental Sciences, School of Biological Sciences, Highfield Campus, SO17 1BJ Southampton, UK
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Zhang J, Zhang Y. Ecophysiological responses of the biocrust moss
Syntrichia caninervis
to experimental snow cover manipulations in a temperate desert of central Asia. Ecol Res 2019. [DOI: 10.1111/1440-1703.12072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jing Zhang
- CAS Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Xinjiang People's Republic of China
| | - Yuanming Zhang
- CAS Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Xinjiang People's Republic of China
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Männistö M, Vuosku J, Stark S, Saravesi K, Suokas M, Markkola A, Martz F, Rautio P. Bacterial and fungal communities in boreal forest soil are insensitive to changes in snow cover conditions. FEMS Microbiol Ecol 2019; 94:5043222. [PMID: 29939247 DOI: 10.1093/femsec/fiy123] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 06/22/2018] [Indexed: 02/06/2023] Open
Abstract
The northern regions are experiencing considerable changes in winter climate leading to more frequent warm periods, rain-on-snow events and reduced snow pack diminishing the insulation properties of snow cover and increasing soil frost and freeze-thaw cycles. In this study, we investigated how the lack of snow cover, formation of ice encasement and snow compaction affect the size, structure and activities of soil bacterial and fungal communities. Contrary to our hypotheses, snow manipulation treatments over one winter had limited influence on microbial community structure, bacterial or fungal copy numbers or enzyme activities. However, microbial community structure and activities shifted seasonally among soils sampled before snow melt, in early and late growing season and seemed driven by substrate availability. Bacterial and fungal communities were dominated by stress-resistant taxa such as the orders Acidobacteriales, Chaetothyriales and Helotiales that are likely adapted to adverse winter conditions. This study indicated that microbial communities in acidic northern boreal forest soil may be insensitive to direct effects of changing snow cover. However, in long term, the detrimental effects of increased ice and frost to plant roots may alter plant derived carbon and nutrient pools to the soil likely leading to stronger microbial responses.
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Affiliation(s)
- Minna Männistö
- Natural Resources Institute Finland, P.O. Box 16, FI-96301 Rovaniemi, Finland
| | - Jaana Vuosku
- Natural Resources Institute Finland, P.O. Box 16, FI-96301 Rovaniemi, Finland
| | - Sari Stark
- Natural Resources Institute Finland, P.O. Box 16, FI-96301 Rovaniemi, Finland.,Arctic Centre, University of Lapland, P.O. Box 122, FI-96101 Rovaniemi, Finland
| | - Karita Saravesi
- Department of Ecology and Genetics, P.O. Box 3000, FI-90014 University of Oulu, Finland
| | - Marko Suokas
- Department of Ecology and Genetics, P.O. Box 3000, FI-90014 University of Oulu, Finland
| | - Annamari Markkola
- Department of Ecology and Genetics, P.O. Box 3000, FI-90014 University of Oulu, Finland
| | - Françoise Martz
- Natural Resources Institute Finland, P.O. Box 16, FI-96301 Rovaniemi, Finland
| | - Pasi Rautio
- Natural Resources Institute Finland, P.O. Box 16, FI-96301 Rovaniemi, Finland
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Bourgeois I, Savarino J, Némery J, Caillon N, Albertin S, Delbart F, Voisin D, Clément JC. Atmospheric nitrate export in streams along a montane to urban gradient. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 633:329-340. [PMID: 29574377 DOI: 10.1016/j.scitotenv.2018.03.141] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 03/11/2018] [Accepted: 03/13/2018] [Indexed: 06/08/2023]
Abstract
Nitrogen (N) emissions associated with urbanization exacerbate the atmospheric N influx to remote ecosystems - like mountains -, leading to well-documented detrimental effects on ecosystems (e.g., soil acidification, pollution of freshwaters). Here, the importance and fate of N deposition in a watershed was evaluated along a montane to urban gradient, using a multi-isotopic tracers approach (Δ17O, δ15N, δ18O of nitrate, δ2H and δ18O of water). In this setting, the montane streams had higher proportions of atmospheric nitrate compared to urban streams, and exported more atmospheric nitrate on a yearly basis (0.35 vs 0.10 kg-Nha-1yr-1). In urban areas, nitrate exports were driven by groundwater, whereas in the catchment head nitrate exports were dominated by surface runoff. The main sources of nitrate to the montane streams were microbial nitrification and atmospheric deposition, whereas microbial nitrification and sewage leakage contributed most to urban streams. Based on the measurement of δ15N and δ18O-NO3-, biological processes such as denitrification or N assimilation were not predominant in any streams in this study. The observed low δ15N and δ18O range of terrestrial nitrate (i.e., nitrate not coming from atmospheric deposition) in surface water compared to literature suggests that atmospheric deposition may be underestimated as a direct source of N.
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Affiliation(s)
- Ilann Bourgeois
- Université Grenoble Alpes, CNRS, IRD, Grenoble INP(1), IGE, F-38000 Grenoble, France; Université Grenoble Alpes, CNRS, LECA, F-38000 Grenoble, France.
| | - Joel Savarino
- Université Grenoble Alpes, CNRS, IRD, Grenoble INP(1), IGE, F-38000 Grenoble, France
| | - Julien Némery
- Université Grenoble Alpes, CNRS, IRD, Grenoble INP(1), IGE, F-38000 Grenoble, France
| | - Nicolas Caillon
- Université Grenoble Alpes, CNRS, IRD, Grenoble INP(1), IGE, F-38000 Grenoble, France
| | - Sarah Albertin
- Université Grenoble Alpes, CNRS, IRD, Grenoble INP(1), IGE, F-38000 Grenoble, France
| | - Franck Delbart
- Université Grenoble Alpes, CNRS, SAJF, F-38000 Grenoble, France
| | - Didier Voisin
- Université Grenoble Alpes, CNRS, IRD, Grenoble INP(1), IGE, F-38000 Grenoble, France
| | - Jean-Christophe Clément
- Université Grenoble Alpes, CNRS, LECA, F-38000 Grenoble, France; Université Savoie Mont Blanc, INRA, CARRTEL, F-74200 Thonon-Les Bains, France
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Analyzing the Effects of Growing Season Length on the Net Ecosystem Production of an Alpine Grassland Using Model–Data Fusion. Ecosystems 2017. [DOI: 10.1007/s10021-017-0201-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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