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Short Gianotti DJ, McColl KA, Feldman AF, Xu X, Entekhabi D. Two sub-annual timescales and coupling modes for terrestrial water and carbon cycles. GLOBAL CHANGE BIOLOGY 2024; 30:e17463. [PMID: 39120552 DOI: 10.1111/gcb.17463] [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: 02/01/2024] [Revised: 07/25/2024] [Accepted: 07/30/2024] [Indexed: 08/10/2024]
Abstract
To bridge the knowledge gap between (a) our (instantaneous-to-seasonal-scale) process understanding of plants and water and (b) our projections of long-term coupled feedbacks between the terrestrial water and carbon cycles, we must uncover what the dominant dynamics are linking fluxes of water and carbon. This study uses the simplest empirical dynamical systems models-two-dimensional linear models-and observation-based data from satellites, eddy covariance towers, weather stations, and machine-learning-derived products to determine the dominant sub-annual timescales coupling carbon uptake and (normalized) evaporation fluxes. We find two dominant modes across the Contiguous United States: (1) a negative correlation timescale on the order of a few days during which landscapes dry after precipitation and plants increase their carbon uptake through photosynthetic upregulation. (2) A slow, seasonal-scale positive covariation through which landscape drying leads to decreased growth and carbon uptake. The slow (positively correlated) process dominates the joint distribution of local water and carbon variables, leading to similar behaviors across space, biomes, and climate regions. We propose that vegetation cover/leaf area variables link this behavior across space, leading to strong emergent spatial patterns of water/carbon coupling in the mean. The spatial pattern of local temporal dynamics-positively sloped tangent lines to a convex long-term mean-state curve-is surprisingly strong, and can serve as a benchmark for coupled Earth System Models. We show that many such models do not represent this emergent mean-state pattern, and hypothesize that this may be due to lack of water-carbon feedbacks at daily scales.
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Affiliation(s)
- Daniel J Short Gianotti
- Ralph M. Parsons Laboratory for Environmental Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Kaighin A McColl
- Department of Earth & Planetary Sciences, Harvard University, Cambridge, Massachusetts, USA
- John A Paulson School of Engineering & Applied Sciences, Harvard University, Cambridge, Massachusetts, USA
| | - Andrew F Feldman
- Biospheric Sciences Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
- Earth System Science Interdisciplinary Center, University of Maryland, Greenbelt, Maryland, USA
| | - Xiangtao Xu
- Department of Ecology & Evolutionary Biology, Cornell University, Ithaca, New York, USA
| | - Dara Entekhabi
- Ralph M. Parsons Laboratory for Environmental Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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2
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Si H, Wang R, Li X. Temporal and spatial evolution simulation and attribution analysis of vegetation photosynthesis over the past 21 years based on satellite SIF data: a case study from Asia. ENVIRONMENTAL MONITORING AND ASSESSMENT 2024; 196:597. [PMID: 38842642 DOI: 10.1007/s10661-024-12755-3] [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: 01/29/2024] [Accepted: 05/25/2024] [Indexed: 06/07/2024]
Abstract
Photosynthesis in vegetation is one of the key processes in maintaining regional ecological balance and climate stability, and it is of significant importance for understanding the health of regional ecosystems and addressing climate change. Based on 2001-2021 Global OCO-2 Solar-Induced Fluorescence (GOSIF) dataset, this study analyzed spatiotemporal variations in Asian vegetation photosynthesis and its response to climate and human activities. Results show the following: (1) From 2001 to 2021, the overall photosynthetic activity of vegetation in the Asian region has shown an upward trend, exhibiting a stable distribution pattern with higher values in the eastern and southern regions and lower values in the central, western, and northern regions. In specific regions such as the Turgen Plateau in northwestern Kazakhstan, Cambodia, Laos, and northeastern Syria, photosynthesis significantly declined. (2) Meteorological factors influencing photosynthesis exhibit differences based on latitude and vertical zones. In low-latitude regions, temperature is the primary driver, while in mid-latitude areas, solar radiation and precipitation are crucial. High-latitude regions are primarily influenced by temperature, and high-altitude areas depend on precipitation and solar radiation. (3) Human activities (56.44%) have a slightly greater impact on the dynamics of Asian vegetation photosynthesis compared to climate change (43.56%). This research deepens our comprehension of the mechanisms behind the fluctuations in Asian vegetation photosynthesis, offering valuable perspectives for initiatives in environmental conservation, sustainability, and climate research.
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Affiliation(s)
- Haixiang Si
- College of Resources and Environment, Shandong Agricultural University, Tai'an, 271018, China
| | - Ruiyan Wang
- College of Resources and Environment, Shandong Agricultural University, Tai'an, 271018, China.
- National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an, 271018, China.
| | - Xiaoteng Li
- College of Resources and Environment, Shandong Agricultural University, Tai'an, 271018, China
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3
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Franks PJ, Herold N, Bonan GB, Oleson KW, Dukes JS, Huber M, Schroeder JI, Cox PM, Jones S. Land surface conductance linked to precipitation: Co-evolution of vegetation and climate in Earth system models. GLOBAL CHANGE BIOLOGY 2024; 30:e17188. [PMID: 38462677 DOI: 10.1111/gcb.17188] [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: 08/23/2023] [Revised: 12/19/2023] [Accepted: 12/27/2023] [Indexed: 03/12/2024]
Abstract
Vegetation and precipitation are known to fundamentally influence each other. However, this interdependence is not fully represented in climate models because the characteristics of land surface (canopy) conductance to water vapor and CO2 are determined independently of precipitation. Working within a coupled atmosphere and land modelling framework (CAM6/CLM5; coupled Community Atmosphere Model v6/Community Land Model v5), we have developed a new theoretical approach to characterizing land surface conductance by explicitly linking its dynamic properties to local precipitation, a robust proxy for moisture available to vegetation. This will enable regional surface conductance characteristics to shift fluidly with climate change in simulations, consistent with general principles of co-evolution of vegetation and climate. Testing within the CAM6/CLM5 framework shows that climate simulations incorporating the new theory outperform current default configurations across several error metrics for core output variables when measured against observational data. In climate simulations for the end of this century the new, adaptive stomatal conductance scheme provides a revised prognosis for average and extreme temperatures over several large regions, with increased primary productivity through central and east Asia, and higher rainfall through North Africa and the Middle East. The new projections also reveal more frequent heatwaves than originally estimated for the south-eastern US and sub-Saharan Africa but less frequent heatwaves across east Europe and northeast Asia. These developments have implications for evaluating food security and risks from extreme temperatures in areas that are vulnerable to climate change.
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Affiliation(s)
- Peter J Franks
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia
| | - Nicholas Herold
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia
| | - Gordon B Bonan
- National Center for Atmospheric Research, Boulder, Colorado, USA
| | - Keith W Oleson
- National Center for Atmospheric Research, Boulder, Colorado, USA
| | - Jeffrey S Dukes
- Department of Global Ecology, Carnegie Institution for Science, Stanford, California, USA
| | - Matthew Huber
- Department of Earth, Atmosphere and Planetary Sciences, Purdue University, West Lafayette, Indiana, USA
| | - Julian I Schroeder
- Cell and Developmental Biology Department, University of California San Diego, San Diego, California, USA
| | - Peter M Cox
- Department of Mathematics and Statistics, University of Exeter, Exeter, UK
| | - Simon Jones
- Department of Mathematics and Statistics, University of Exeter, Exeter, UK
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4
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Parra A, Greenberg J. Climate-limited vegetation change in the conterminous United States of America. GLOBAL CHANGE BIOLOGY 2024; 30:e17204. [PMID: 38396327 DOI: 10.1111/gcb.17204] [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: 09/17/2023] [Revised: 02/02/2024] [Accepted: 02/05/2024] [Indexed: 02/25/2024]
Abstract
The effects of climate change on vegetation composition and distribution are evident in different ecosystems around the world. Although some climate-derived alterations on vegetation are expected to result in changes in lifeform fractional cover, disentangling the direct effects of climate change from different non-climate factors, such as land-use change, is challenging. By applying "Liebig's law of the minimum" in a geospatial context, we determined the climate-limited potential for tree, shrub, herbaceous, and non-vegetation fractional cover change for the conterminous United States and compared these potential rates to observed change rates for the period 1986 to 2018. We found that 10% of the land area of the conterminous United States appears to have climate limitations on the change in fractional cover, with a high proportion of these sites located in arid and semiarid ecosystems in the Southwest part of the country. The rates of change in lifeform fractional cover for the remaining area of the country are likely limited by non-climate factors such as the disturbance regime, land management, land-use history, soil conditions, and species interactions and adaptations.
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Affiliation(s)
- Adriana Parra
- Department of Natural Resources and Environmental Science, University of Nevada, Reno, Nevada, USA
| | - Jonathan Greenberg
- Department of Natural Resources and Environmental Science, University of Nevada, Reno, Nevada, USA
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5
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Saibu S, Uhanie Perera I, Suzuki S, Rodó X, Fujiyoshi S, Maruyama F. Resistomes in freshwater bioaerosols and their impact on drinking and recreational water safety: A perspective. ENVIRONMENT INTERNATIONAL 2024; 183:108377. [PMID: 38103344 DOI: 10.1016/j.envint.2023.108377] [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: 10/01/2023] [Revised: 12/07/2023] [Accepted: 12/07/2023] [Indexed: 12/19/2023]
Abstract
Antibiotic resistance genes (ARGs) are widespread environmental pollutants of biological origin that pose a significant threat to human, animal, and plant health, as well as to ecosystems. ARGs are found in soil, water, air, and waste, and several pathways for global dissemination in the environment have been described. However, studies on airborne ARG transport through atmospheric particles are limited. The ARGs in microorganisms inhabiting an environment are referred to as the "resistome". A global search was conducted of air-resistome studies by retrieving bioaerosol ARG-related papers published in the last 30 years from PubMed. We found that there is no dedicated methodology for isolating ARGs in bioaerosols; instead, conventional methods for microbial culture and metagenomic analysis are used in combination with standard aerosol sampling techniques. There is a dearth of information on the bioaerosol resistomes of freshwater environments and their impact on freshwater sources used for drinking and recreational activities. More studies of aerobiome freshwater environments are needed to ensure the safe use of water and sanitation. In this review we outline and synthesize the few studies that address the freshwater air microbiome (from tap water, bathroom showers, rivers, lakes, and swimming pools) and their resistomes, as well as the likely impacts on drinking and recreational waters. We also discuss current knowledge gaps for the freshwater airborne resistome. This review will stimulate new investigations of the atmospheric microbiome, particularly in areas where both air and water quality are of public health concern.
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Affiliation(s)
- Salametu Saibu
- Department of Microbiology, Lagos State University of Ojo, Lagos, Nigeria
| | - Ishara Uhanie Perera
- Section of Microbial Genomics and Ecology, Planetary Health and Innovation Science Center (PHIS), The IDEC Institute, Hiroshima University, Japan
| | - Satoru Suzuki
- Graduate School of Science and Engineering, Center for Marine Environmental Studies, Ehime University, Japan
| | - Xavier Rodó
- ICREA and CLIMA Program, Barcelona Institute for Global Health (-ISGlobal), Barcelona, Spain
| | - So Fujiyoshi
- Section of Microbial Genomics and Ecology, Planetary Health and Innovation Science Center (PHIS), The IDEC Institute, Hiroshima University, Japan
| | - Fumito Maruyama
- Section of Microbial Genomics and Ecology, Planetary Health and Innovation Science Center (PHIS), The IDEC Institute, Hiroshima University, Japan.
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6
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Hou J, HuibinYu, Wu F, Xi B, Li Z. Applying fluorescence spectroscopy and DNA pyrosequencing with 2D-COS and co-occurrence network to deconstruct dynamical DOM degradation of air-land-water sources in an urban river. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 904:166794. [PMID: 37673237 DOI: 10.1016/j.scitotenv.2023.166794] [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: 07/07/2023] [Revised: 08/14/2023] [Accepted: 09/01/2023] [Indexed: 09/08/2023]
Abstract
In an urban river, comprehending the interplay between dissolved organic matter (DOM) and atmospheric, terrestrial, and aquatic sources is crucial. This encompassed investigating temporal variations in DOM and its association with the bacterioplankton community to gain profound insights into the biogeochemical dynamics and biodegradability of DOM. DOM was extracted from PM2.5, soil, sediment, bait, and terrestrial/aquatic plant residuals collected along the Wenyuhe River in Beijing, China - a region predominantly supplied with reclaimed water. Subsequently, mixed microbial communities from the river were introduced into DOM samples originating from each source and incubated for 10 days. Principal component analysis (PCA) applied to reassembled excitation-emission matrix (EEM) data revealed two distinct clusters: cluster 1 comprising soil, sediment, and PM2.5 samples; and cluster 2 consisting of bait as well as terrestrial/aquatic plant residuals. According to parallel factor analysis, C1 (microbial humic-like) and C2-C3 (fulvic-like) dominated the DOM from soil, sediment, and PM2.5. These components were continuously degraded during incubation, except for PM2.5. DOM from bait and terrestrial/aquatic plants contained representative components of C6 (phenolic-like) and C7 (tryptophan-like), which underwent extensive decomposition. Interestingly, DOM in PM2.5 contained aliphatic compounds and polycyclic aromatic hydrocarbons (PAHs) but exhibited weak degradation with the complete disappearance of C6 and C7. Rhodococcus was a unique species capable of degrading PAHs, which might be particularly important considering the specificity of PM2.5 pollution. Based on two-dimensional correlation spectroscopy (2D-COS), variations in DOM components such as C6, and C7 were significantly larger compared to those of C1, C2, C3, and C5 (terrestrial humic-like) from bait samples, sediments, and residual terrestrial plants. MW-2D-COS analysis revealed that DOM from bait samples and terrestrial/aquatic plants experienced substantial degradation by the second day while DOM from soil or sediment decomposed mainly on the fourth day. Notably, the decomposition of DOM fractions in PM2.5 occurred throughout the entire four-day period. Co-occurrence network analysis classified sources of DOM into two clusters similar to PCA results: cluster 1 showed significant microbial degradation of fulvic-like compounds while cluster 2 demonstrated deep microbial decomposition of tyrosine-like and phenolic compounds. Therefore, the artificial loading of DOM into rivers not only expands the chemical diversity within DOM but also perturbs bacterioplankton diversities.
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Affiliation(s)
- Junwen Hou
- State Key Laboratory of Environment Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; College of Water Sciences, Beijing Normal University, Beijing 100875, China
| | - HuibinYu
- State Key Laboratory of Environment Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Fengchang Wu
- State Key Laboratory of Environment Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; College of Water Sciences, Beijing Normal University, Beijing 100875, China.
| | - Beidou Xi
- State Key Laboratory of Environment Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; College of Water Sciences, Beijing Normal University, Beijing 100875, China.
| | - Zhengying Li
- State Key Laboratory of Environment Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
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7
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Yang Z, Gong J, Wang S, Jin T, Wang Y. Shifts bidirectional dependency between vegetation greening and soil moisture over the past four decades in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 897:166388. [PMID: 37597546 DOI: 10.1016/j.scitotenv.2023.166388] [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: 04/25/2023] [Revised: 07/19/2023] [Accepted: 08/16/2023] [Indexed: 08/21/2023]
Abstract
Soil moisture (SM) has changed significantly over the past 40 years in China, while NDVI has varied dramatically, leading to increasing regional conflict between vegetation growth and water resource use. Quantifying the bidirectional dependency between SM and NDVI is essential for understanding the balance between land vegetation and water resources. However, few studies have reported their mutual feedback and spatiotemporal bidirectional dependency. This paper aims to reveal the bidirectional dependency between SM and NDVI using Granger causality test to show spatiotemporal tendency coupling patterns through trend coupling analysis, wavelet transform, and lag correlation. The Results indicated that a coupling relationship existed between SM and NDVI over most of China. The unidirectional Granger effect between SM on NDVI was 58 %, the unidirectional Granger effect of NDVI on SM was 26 %, and the bidirectional Granger relationship between SM and NDVI was 16 %. The Granger relationship is different for different soil layers or land cover types. SM and NDVI increased together in 36 % of the land cover areas, but SM increased and NDVI decreased in 12 %, and the SM decreased and NDVI increased in 27 %. The trend coupling between SM and NDVI has spatial heterogeneity. There is no change rule of coupling relationship with drought variation, but SM and NDVI increased together with more overlapping ecological restoration projects. SM decreased with the increase of NDVI from 1982 to 2010 but has reversed since 2011. NDVI and SM co-increased significantly with the implementation of ecological restoration projects during 2011-2022. The coupling relationship has a time lag effect of 1-3 months, and the time lag of NDVI to SM of deep soil layers mainly occurred in Southern China. This study illustrated the coupling framework and feedback analysis between SM and vegetation greening, which is helpful for the scientific implementing ecological restoration projects and the management of ecosystem carbon and water cycles.
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Affiliation(s)
- Zhihui Yang
- Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
| | - Jie Gong
- Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China.
| | - Shimei Wang
- Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
| | - Tiantian Jin
- Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
| | - Yixu Wang
- Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
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8
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Giardina F, Gentine P, Konings AG, Seneviratne SI, Stocker BD. Diagnosing evapotranspiration responses to water deficit across biomes using deep learning. THE NEW PHYTOLOGIST 2023; 240:968-983. [PMID: 37621238 DOI: 10.1111/nph.19197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 07/23/2023] [Indexed: 08/26/2023]
Abstract
Accounting for water limitation is key to determining vegetation sensitivity to drought. Quantifying water limitation effects on evapotranspiration (ET) is challenged by the heterogeneity of vegetation types, climate zones and vertically along the rooting zone. Here, we train deep neural networks using flux measurements to study ET responses to progressing drought conditions. We determine a water stress factor (fET) that isolates ET reductions from effects of atmospheric aridity and other covarying drivers. We regress fET against the cumulative water deficit, which reveals the control of whole-column moisture availability. We find a variety of ET responses to water stress. Responses range from rapid declines of fET to 10% of its water-unlimited rate at several savannah and grassland sites, to mild fET reductions in most forests, despite substantial water deficits. Most sensitive responses are found at the most arid and warm sites. A combination of regulation of stomatal and hydraulic conductance and access to belowground water reservoirs, whether in groundwater or deep soil moisture, could explain the different behaviors observed across sites. This variety of responses is not captured by a standard land surface model, likely reflecting simplifications in its representation of belowground water storage.
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Affiliation(s)
- Francesco Giardina
- Institute of Agricultural Sciences, Department of Environmental Systems Science, ETH Zürich, Zürich, CH-8092, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
- Center for Learning the Earth with Artificial Intelligence and Physics (LEAP), Columbia University, New York, NY, 10027, USA
| | - Alexandra G Konings
- Department of Earth System Science, Stanford University, Stanford, CA, 94305, USA
| | - Sonia I Seneviratne
- Institute for Atmospheric and Climate Science, Department of Environmental Systems Science, ETH Zurich, Zürich, CH-8092, Switzerland
| | - Benjamin D Stocker
- Institute of Agricultural Sciences, Department of Environmental Systems Science, ETH Zürich, Zürich, CH-8092, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
- Institute of Geography, University of Bern, Hallerstrasse 12, Bern, 3012, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, Falkenplatz 16, Bern, 3012, Switzerland
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9
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Feldman AF, Zhang Z, Yoshida Y, Gentine P, Chatterjee A, Entekhabi D, Joiner J, Poulter B. A multi-satellite framework to rapidly evaluate extreme biosphere cascades: The Western US 2021 drought and heatwave. GLOBAL CHANGE BIOLOGY 2023; 29:3634-3651. [PMID: 37070967 DOI: 10.1111/gcb.16725] [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: 12/26/2022] [Accepted: 04/04/2023] [Indexed: 06/06/2023]
Abstract
The increasing frequency and intensity of climate extremes and complex ecosystem responses motivate the need for integrated observational studies at low latency to determine biosphere responses and carbon-climate feedbacks. Here, we develop a satellite-based rapid attribution workflow and demonstrate its use at a 1-2-month latency to attribute drivers of the carbon cycle feedbacks during the 2020-2021 Western US drought and heatwave. In the first half of 2021, concurrent negative photosynthesis anomalies and large positive column CO2 anomalies were detected with satellites. Using a simple atmospheric mass balance approach, we estimate a surface carbon efflux anomaly of 132 TgC in June 2021, a magnitude corroborated independently with a dynamic global vegetation model. Integrated satellite observations of hydrologic processes, representing the soil-plant-atmosphere continuum (SPAC), show that these surface carbon flux anomalies are largely due to substantial reductions in photosynthesis because of a spatially widespread moisture-deficit propagation through the SPAC between 2020 and 2021. A causal model indicates deep soil moisture stores partially drove photosynthesis, maintaining its values in 2020 and driving its declines throughout 2021. The causal model also suggests legacy effects may have amplified photosynthesis deficits in 2021 beyond the direct effects of environmental forcing. The integrated, observation framework presented here provides a valuable first assessment of a biosphere extreme response and an independent testbed for improving drought propagation and mechanisms in models. The rapid identification of extreme carbon anomalies and hotspots can also aid mitigation and adaptation decisions.
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Affiliation(s)
- Andrew F Feldman
- Biospheric Sciences Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
- NASA Postdoctoral Program, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
| | - Zhen Zhang
- Earth System Science Interdisciplinary Center, University of Maryland, College Park, Maryland, USA
| | - Yasuko Yoshida
- Science Systems and Applications, Inc. (SSAI), Lanham, Maryland, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, New York, USA
| | - Abhishek Chatterjee
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Dara Entekhabi
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Joanna Joiner
- Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
| | - Benjamin Poulter
- Biospheric Sciences Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
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10
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Sun Y, Wen J, Gu L, Joiner J, Chang CY, van der Tol C, Porcar-Castell A, Magney T, Wang L, Hu L, Rascher U, Zarco-Tejada P, Barrett CB, Lai J, Han J, Luo Z. From remotely-sensed solar-induced chlorophyll fluorescence to ecosystem structure, function, and service: Part II-Harnessing data. GLOBAL CHANGE BIOLOGY 2023; 29:2893-2925. [PMID: 36802124 DOI: 10.1111/gcb.16646] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 02/09/2023] [Accepted: 02/14/2023] [Indexed: 05/03/2023]
Abstract
Although our observing capabilities of solar-induced chlorophyll fluorescence (SIF) have been growing rapidly, the quality and consistency of SIF datasets are still in an active stage of research and development. As a result, there are considerable inconsistencies among diverse SIF datasets at all scales and the widespread applications of them have led to contradictory findings. The present review is the second of the two companion reviews, and data oriented. It aims to (1) synthesize the variety, scale, and uncertainty of existing SIF datasets, (2) synthesize the diverse applications in the sector of ecology, agriculture, hydrology, climate, and socioeconomics, and (3) clarify how such data inconsistency superimposed with the theoretical complexities laid out in (Sun et al., 2023) may impact process interpretation of various applications and contribute to inconsistent findings. We emphasize that accurate interpretation of the functional relationships between SIF and other ecological indicators is contingent upon complete understanding of SIF data quality and uncertainty. Biases and uncertainties in SIF observations can significantly confound interpretation of their relationships and how such relationships respond to environmental variations. Built upon our syntheses, we summarize existing gaps and uncertainties in current SIF observations. Further, we offer our perspectives on innovations needed to help improve informing ecosystem structure, function, and service under climate change, including enhancing in-situ SIF observing capability especially in "data desert" regions, improving cross-instrument data standardization and network coordination, and advancing applications by fully harnessing theory and data.
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Affiliation(s)
- Ying Sun
- School of Integrative Plant Science, Soil and Crop Sciences Section, Cornell University, Ithaca, New York, USA
| | - Jiaming Wen
- School of Integrative Plant Science, Soil and Crop Sciences Section, Cornell University, Ithaca, New York, USA
| | - Lianhong Gu
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Joanna Joiner
- National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC), Greenbelt, Maryland, USA
| | - Christine Y Chang
- US Department of Agriculture, Agricultural Research Service, Adaptive Cropping Systems Laboratory, Beltsville, Maryland, USA
| | - Christiaan van der Tol
- Affiliation Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, Enschede, The Netherlands
| | - Albert Porcar-Castell
- Optics of Photosynthesis Laboratory, Institute for Atmospheric and Earth System Research (INAR)/Forest Sciences, Viikki Plant Science Center (ViPS), University of Helsinki, Helsinki, Finland
| | - Troy Magney
- Department of Plant Sciences, University of California, Davis, Davis, California, USA
| | - Lixin Wang
- Department of Earth Sciences, Indiana University-Purdue University Indianapolis (IUPUI), Indianapolis, Indiana, USA
| | - Leiqiu Hu
- Department of Atmospheric and Earth Science, University of Alabama in Huntsville, Huntsville, Alabama, USA
| | - Uwe Rascher
- Institute of Bio- and Geosciences, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Pablo Zarco-Tejada
- School of Agriculture and Food (SAF-FVAS) and Faculty of Engineering and Information Technology (IE-FEIT), University of Melbourne, Melbourne, Victoria, Australia
| | - Christopher B Barrett
- Charles H. Dyson School of Applied Economics and Management, Cornell University, Ithaca, New York, USA
| | - Jiameng Lai
- School of Integrative Plant Science, Soil and Crop Sciences Section, Cornell University, Ithaca, New York, USA
| | - Jimei Han
- School of Integrative Plant Science, Soil and Crop Sciences Section, Cornell University, Ithaca, New York, USA
| | - Zhenqi Luo
- School of Integrative Plant Science, Soil and Crop Sciences Section, Cornell University, Ithaca, New York, USA
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11
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Xu X, Liu J, Jiao F, Zhang K, Ye X, Gong H, Lin N, Zou C. Ecological engineering induced carbon sinks shifting from decreasing to increasing during 1981-2019 in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 864:161037. [PMID: 36565873 DOI: 10.1016/j.scitotenv.2022.161037] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 12/13/2022] [Accepted: 12/15/2022] [Indexed: 06/17/2023]
Abstract
Substantial evidence shows that most of China's terrestrial ecosystems are important carbon sinks. However, the nonlinear trend of the carbon sinks and their nonlinear response to driving factors are unclear. Taking the net ecosystem productivity (NEP) as a proxy for the ecosystem carbon sink, the nonlinear relationships between the monotonically increasing trends and decreasing to increasing shifts in the carbon sink to climate change and ecological engineering were investigated based on ensemble empirical mode decomposition (EEMD) and machine learning algorithm (boosted regression tree model, BRT). The results suggest that 16.75 % of the carbon sinks in China experienced a monotonic increase. Additionally, 20.55 % of the carbon sinks shifted from decreasing to increasing trends, primarily after 1995, and these carbon sinks were located in the key ecological engineering areas, such as the middle reaches of the Yellow River shelterbelt program area, the Liaohe shelterbelt program area, the Grain to Green program area, and the Three-North Forest shelterbelt program area. Moreover, carbon sinks exhibited strong spatial autocorrelation with low-low clustering in the north and high-high clustering in the south. The increase in CO2 (slope of CO2 < 1.8 g/m2/s/y) and solar radiation (slope of radiation >1 w/m2/y) promoted the monotonic increase in the carbon sinks in the center of China. The increase in the areas of forest and grassland shifted the carbon sink trend from decreasing to increasing in the key ecological engineering program areas, and economic development reversed the carbon sink reduction in the Pearl River shelterbelt program area. These findings highlight the positive effect of ecological engineering on carbon sinks and provide adaptation strategies and guidance for China to achieve the "carbon neutrality" target.
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Affiliation(s)
- Xiaojuan Xu
- Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China
| | - Jing Liu
- Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China
| | - Fusheng Jiao
- School of Geography, Nanjing Normal University, Nanjing 210023, China
| | - Kun Zhang
- Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China
| | - Xin Ye
- Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China
| | - Haibo Gong
- School of Geography, Nanjing Normal University, Nanjing 210023, China
| | - Naifeng Lin
- Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China.
| | - Changxin Zou
- Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China.
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12
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Soil-vegetation moisture capacitor maintains dry season vegetation productivity over India. Sci Rep 2023; 13:888. [PMID: 36650187 PMCID: PMC9845320 DOI: 10.1038/s41598-022-27277-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 12/29/2022] [Indexed: 01/19/2023] Open
Abstract
India receives more than 70% of its annual rainfall in the summer monsoon from June to September. The rainfall is scanty and scattered for the rest of the year. Combining satellite data and model simulations, we show that the soil-vegetation continuum works as a natural capacitor of water, storing the monsoon pulse and releasing the moisture to the atmosphere through evapotranspiration over approximately 135 days when the moisture supply from precipitation is less than the evapotranspiration losses. The total Gross Primary Productivity of vegetation in India during the capacitor period accounts for almost 35% of the total annual GPP value. It primarily depends on the soil moisture at the beginning of the period, a measure of moisture capacitance of soil, with a correlation of 0.6. Given that India is the second largest contributor to recent global greening, its soil-vegetation water capacitance plays a significant role in the global carbon balance.
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13
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Feldman AF, Short Gianotti DJ, Dong J, Trigo IF, Salvucci GD, Entekhabi D. Tropical surface temperature response to vegetation cover changes and the role of drylands. GLOBAL CHANGE BIOLOGY 2023; 29:110-125. [PMID: 36169920 PMCID: PMC10092849 DOI: 10.1111/gcb.16455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
Vegetation cover creates competing effects on land surface temperature: it typically cools through enhancing energy dissipation and warms via decreasing surface albedo. Global vegetation has been previously found to overall net cool land surfaces with cooling contributions from temperate and tropical vegetation and warming contributions from boreal vegetation. Recent studies suggest that dryland vegetation across the tropics strongly contributes to this global net cooling feedback. However, observation-based vegetation-temperature interaction studies have been limited in the tropics, especially in their widespread drylands. Theoretical considerations also call into question the ability of dryland vegetation to strongly cool the surface under low water availability. Here, we use satellite observations to investigate how tropical vegetation cover influences the surface energy balance. We find that while increased vegetation cover would impart net cooling feedbacks across the tropics, net vegetal cooling effects are subdued in drylands. Using observations, we determine that dryland plants have less ability to cool the surface due to their cooling pathways being reduced by aridity, overall less efficient dissipation of turbulent energy, and their tendency to strongly increase solar radiation absorption. As a result, while proportional greening across the tropics would create an overall biophysical cooling feedback, dryland tropical vegetation reduces the overall tropical surface cooling magnitude by at least 14%, instead of enhancing cooling as suggested by previous global studies.
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Affiliation(s)
- Andrew F. Feldman
- Biospheric Sciences LaboratoryNASA Goddard Space Flight CenterGreenbeltMarylandUSA
- NASA Postdoctoral ProgramNASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - Daniel J. Short Gianotti
- Department of Civil and Environmental EngineeringMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
| | - Jianzhi Dong
- Department of Civil and Environmental EngineeringMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
| | - Isabel F. Trigo
- Instituto Português do Mar e da Atmosfera I.P. (IPMA)LisbonPortugal
- Instituto Dom Luiz (IDL)LisbonPortugal
| | - Guido D. Salvucci
- Department of Earth and EnvironmentBoston UniversityBostonMassachusettsUSA
| | - Dara Entekhabi
- Department of Civil and Environmental EngineeringMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
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14
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Te Wierik SA, Keune J, Miralles DG, Gupta J, Artzy‐Randrup YA, Gimeno L, Nieto R, Cammeraat LH. The Contribution of Transpiration to Precipitation Over African Watersheds. WATER RESOURCES RESEARCH 2022; 58:e2021WR031721. [PMID: 36582769 PMCID: PMC9786354 DOI: 10.1029/2021wr031721] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 09/09/2022] [Accepted: 10/09/2022] [Indexed: 06/17/2023]
Abstract
The redistribution of biological (transpiration) and non-biological (interception loss, soil evaporation) fluxes of terrestrial evaporation via atmospheric circulation and precipitation is an important Earth system process. In vegetated ecosystems, transpiration dominates terrestrial evaporation and is thought to be crucial for regional moisture recycling and ecosystem functioning. However, the spatial and temporal variability in the dependency of precipitation on transpiration remains understudied, particularly in sparsely sampled regions like Africa. Here, we investigate how biological and non-biological sources of evaporation in Africa contribute to rainfall over the major watersheds in the continent. Our study is based on simulated atmospheric moisture trajectories derived from the Lagrangian model FLEXPART, driven by 1° resolution reanalysis data over 1981-2016. Using daily satellite-based fractions of transpiration over terrestrial evaporation, we isolate the contribution of vegetation to monthly rainfall. Furthermore, we highlight two watersheds (Congo and Senegal) for which we explore intra- and interannual variability of different precipitation sources, and where we find contrasting patterns of vegetation-sourced precipitation within and between years. Overall, our results show that almost 50% of the annual rainfall in Africa originates from transpiration, although the variability between watersheds is large (5%-68%). We conclude that, considering the current and projected patterns of land use change in Africa, a better understanding of the implications for continental-scale water availability is needed.
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Affiliation(s)
- S. A. Te Wierik
- Institute for Biodiversity and Ecosystem DynamicsUniversity of AmsterdamAmsterdamThe Netherlands
- Governance and Inclusive DevelopmentUniversity of AmsterdamAmsterdamThe Netherlands
| | - J. Keune
- Hydro‐Climate Extremes LabGhent UniversityGhentBelgium
| | | | - J. Gupta
- Governance and Inclusive DevelopmentUniversity of AmsterdamAmsterdamThe Netherlands
| | - Y. A. Artzy‐Randrup
- Institute for Biodiversity and Ecosystem DynamicsUniversity of AmsterdamAmsterdamThe Netherlands
| | - L. Gimeno
- Environmental Physics Laboratory (EPhysLab)Centro de Investigación MariñaUniversidade de VigoVigoSpain
| | - R. Nieto
- Environmental Physics Laboratory (EPhysLab)Centro de Investigación MariñaUniversidade de VigoVigoSpain
| | - L. H. Cammeraat
- Institute for Biodiversity and Ecosystem DynamicsUniversity of AmsterdamAmsterdamThe Netherlands
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15
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Increasing sensitivity of dryland vegetation greenness to precipitation due to rising atmospheric CO2. Nat Commun 2022; 13:4875. [PMID: 35985990 PMCID: PMC9391480 DOI: 10.1038/s41467-022-32631-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 08/05/2022] [Indexed: 11/09/2022] Open
Abstract
Water availability plays a critical role in shaping terrestrial ecosystems, particularly in low- and mid-latitude regions. The sensitivity of vegetation growth to precipitation strongly regulates global vegetation dynamics and their responses to drought, yet sensitivity changes in response to climate change remain poorly understood. Here we use long-term satellite observations combined with a dynamic statistical learning approach to examine changes in the sensitivity of vegetation greenness to precipitation over the past four decades. We observe a robust increase in precipitation sensitivity (0.624% yr−1) for drylands, and a decrease (−0.618% yr−1) for wet regions. Using model simulations, we show that the contrasting trends between dry and wet regions are caused by elevated atmospheric CO2 (eCO2). eCO2 universally decreases the precipitation sensitivity by reducing leaf-level transpiration, particularly in wet regions. However, in drylands, this leaf-level transpiration reduction is overridden at the canopy scale by a large proportional increase in leaf area. The increased sensitivity for global drylands implies a potential decrease in ecosystem stability and greater impacts of droughts in these vulnerable ecosystems under continued global change. Changes in vegetation responses to precipitation may be hydroclimate dependent. Here the authors reveal contrasting trends of vegetation sensitivity to precipitation in drylands vs. wetter ecosystems over the last 4 decades and identify increased CO2 as a major contributing factor.
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16
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Rahman T, Candolin U. Linking animal behavior to ecosystem change in disturbed environments. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.893453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Environmental disturbances often cause individuals to change their behavior. The behavioral responses can induce a chain of reactions through the network of species interactions, via consumptive and trait mediated connections. Given that species interactions define ecosystem structure and functioning, changes to these interactions often have ecological repercussions. Here, we explore the transmission of behavioral responses through the network of species interactions, and how the responses influence ecological conditions. We describe the underlying mechanisms and the ultimate impact that the behavioral responses can have on ecosystem structure and functioning, including biodiversity and ecosystems stability and services. We explain why behavioral responses of some species have a larger impact than that of others on ecosystems, and why research should focus on these species and their interactions. With the work, we synthesize existing theory and empirical evidence to provide a conceptual framework that links behavior responses to altered species interactions, community dynamics, and ecosystem processes. Considering that species interactions link biodiversity to ecosystem functioning, a deeper understanding of behavioral responses and their causes and consequences can improve our knowledge of the mechanisms and pathways through which human activities alter ecosystems. This knowledge can improve our ability to predict the effects of ongoing disturbances on communities and ecosystems and decide on the interventions needed to mitigate negative effects.
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17
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Wanner L, Calaf M, Mauder M. Incorporating the effect of heterogeneous surface heating into a semi-empirical model of the surface energy balance closure. PLoS One 2022; 17:e0268097. [PMID: 35648756 PMCID: PMC9159583 DOI: 10.1371/journal.pone.0268097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 04/21/2022] [Indexed: 11/19/2022] Open
Abstract
It was discovered several decades ago that eddy covariance measurements systematically underestimate sensible and latent heat fluxes, creating an imbalance in the surface energy budget. Since then, many studies have addressed this problem and proposed a variety of solutions to the problem, including improvements to instruments and correction methods applied during data postprocessing. However, none of these measures have led to the complete closure of the energy balance gap. The leading hypothesis is that not only surface-attached turbulent eddies but also sub-mesoscale atmospheric circulations contribute to the transport of energy in the atmospheric boundary layer, and the contribution from organized motions has been grossly neglected. The problem arises because the transport of energy through these secondary circulations cannot be captured by the standard eddy covariance method given the relatively short averaging periods of time (~30 minutes) used to compute statistics. There are various approaches to adjust the measured heat fluxes by attributing the missing energy to the sensible and latent heat flux in different proportions. However, few correction methods are based on the processes causing the energy balance gap. Several studies have shown that the magnitude of the energy balance gap depends on the atmospheric stability and the heterogeneity scale of the landscape around the measurement site. Based on this, the energy balance gap within the surface layer has already been modelled as a function of a nonlocal atmospheric stability parameter by performing a large-eddy simulation study with idealized homogeneous surfaces. We have further developed this approach by including thermal surface heterogeneity in addition to atmospheric stability in the parameterization. Specifically, we incorporated a thermal heterogeneity parameter that was shown to relate to the magnitude of the energy balance gap. For this purpose, we use a Large-Eddy Simulation dataset of 28 simulations with seven different atmospheric conditions and three heterogeneous surfaces with different heterogeneity scales as well as one homogeneous surface. The newly developed model captures very well the variability in the magnitude of the energy balance gap under different conditions. The model covers a wide range of both atmospheric stabilities and landscape heterogeneity scales and is well suited for application to eddy covariance measurements since all necessary information can be modelled or obtained from a few additional measurements.
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Affiliation(s)
- Luise Wanner
- Institute of Meteorology and Climate Research, Atmospheric Environmental Research, Karlsruhe Institute of Technology, Garmisch-Partenkirchen, Germany
- Institute of Hydrology and Meteorology, Technische Universität Dresden, Tharandt, Germany
| | - Marc Calaf
- Department of Mechanical Engineering, University of Utah, Salt Lake City, UT, United States of America
| | - Matthias Mauder
- Institute of Meteorology and Climate Research, Atmospheric Environmental Research, Karlsruhe Institute of Technology, Garmisch-Partenkirchen, Germany
- Institute of Hydrology and Meteorology, Technische Universität Dresden, Tharandt, Germany
- Institute of Geography and Geoecology, Karlsruhe Institute of Technology, Karlsruhe, Germany
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18
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Shi M, Worden JR, Bailey A, Noone D, Risi C, Fu R, Worden S, Herman R, Payne V, Pagano T, Bowman K, Bloom AA, Saatchi S, Liu J, Fisher JB. Amazonian terrestrial water balance inferred from satellite-observed water vapor isotopes. Nat Commun 2022; 13:2686. [PMID: 35562340 PMCID: PMC9106687 DOI: 10.1038/s41467-022-30317-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 04/26/2022] [Indexed: 11/09/2022] Open
Abstract
Atmospheric humidity and soil moisture in the Amazon forest are tightly coupled to the region’s water balance, or the difference between two moisture fluxes, evapotranspiration minus precipitation (ET-P). However, large and poorly characterized uncertainties in both fluxes, and in their difference, make it challenging to evaluate spatiotemporal variations of water balance and its dependence on ET or P. Here, we show that satellite observations of the HDO/H2O ratio of water vapor are sensitive to spatiotemporal variations of ET-P over the Amazon. When calibrated by basin-scale and mass-balance estimates of ET-P derived from terrestrial water storage and river discharge measurements, the isotopic data demonstrate that rainfall controls wet Amazon water balance variability, but ET becomes important in regulating water balance and its variability in the dry Amazon. Changes in the drivers of ET, such as above ground biomass, could therefore have a larger impact on soil moisture and humidity in the dry (southern and eastern) Amazon relative to the wet Amazon. The evolution of the Amazon forest is tightly coupled to its terrestrial water balance. Here, the authors show that forest biomass changes in the Amazon are a driver of the spatiotemporal variation of evapotranspiration, and such changes could have a larger impact on water availability in the dry regions (southern, eastern) of the Amazon.
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Affiliation(s)
- Mingjie Shi
- Joint Institute for Regional Earth System Science and Engineering, University of California, Los Angeles, CA, USA. .,Pacific Northwest National Laboratory, 902 Battelle Blvd, Richland, WA, USA.
| | - John R Worden
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA.
| | - Adriana Bailey
- National Center for Atmospheric Research, Boulder, CO, USA
| | - David Noone
- University of Auckland, Auckland, New Zealand
| | - Camille Risi
- Laboratoire de Météorologie Dynamique, Paris, France
| | - Rong Fu
- University of California, Los Angeles, CA, USA
| | | | - Robert Herman
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Vivienne Payne
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Thomas Pagano
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Kevin Bowman
- Joint Institute for Regional Earth System Science and Engineering, University of California, Los Angeles, CA, USA.,Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - A Anthony Bloom
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Sassan Saatchi
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Junjie Liu
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA.,California Institute of Technology, Pasadena, CA, USA
| | - Joshua B Fisher
- Joint Institute for Regional Earth System Science and Engineering, University of California, Los Angeles, CA, USA.,Schmid College of Science and Technology, Chapman University, 1 University Drive, Orange, CA, USA
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19
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Land-Greening Hotspot Changes in the Yangtze River Economic Belt during the Last Four Decades and Their Connections to Human Activities. LAND 2022. [DOI: 10.3390/land11050605] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The spatial patterns of the normalized difference vegetation index (NDVI) changes in the Yangtze River Economic Belt (YREB) and their potential causes during the last four decades remain unclear. To clarify this issue, this study firstly depicts the spatial patterns of the NDVI changes using global inventory modelling and mapping studies (GIMMS) NDVI data and Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI data. Secondly, the Mann–Kendall test, regression residual analysis and cluster analysis are used to diagnose the potential causes of the NDVI changes. The results show that the regional mean NDVI exhibited an uptrend from 1982 to 2019, which consists of two prominent uptrend periods, i.e., 1982–2003 and 2003–2019. There has been a shift of greening hotspots. The first prominent greening trend from 1982 to 2003 mainly occurred in the eastern agricultural area, while the second prominent greening uptrend from 2003 to 2019 mainly occurred at the junction of Chongqing, Guizhou and Yunnan. The greening trend and shift of greening hotspots were slightly caused by climate change, but mainly caused by human activities. The first greening trend was closely related to the agricultural progress, and the second greening trend was associated with the rapid economic development and implementation of ecology restoration policies.
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20
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MoBiMS: A modular miniature mass analyzer for the real-time monitoring of gases and volatile compounds in biological systems. Microchem J 2022. [DOI: 10.1016/j.microc.2021.107090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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21
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Cooley SS, Fisher JB, Goldsmith GR. Convergence in water use efficiency within plant functional types across contrasting climates. NATURE PLANTS 2022; 8:341-345. [PMID: 35422082 DOI: 10.1038/s41477-022-01131-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 03/10/2022] [Indexed: 06/14/2023]
Abstract
Water use efficiency (WUE) provides a direct measure of the inextricable link between plant carbon uptake and water loss, and it can be used to study how ecosystem function varies with climate. We analysed WUE data from the ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS), leveraging the high spatial resolution of ECOSTRESS to study the distribution of WUE values both within and among regions with different plant functional types. Our results indicate that despite wide local variability of WUE estimates, WUE tended to converge to common global optima (peaked distributions with variance <0.5 g C per kg H2O, kurtosis >3.0) for five of nine plant functional types (grassland, permanent wetland, savannah, deciduous broadleaf and deciduous needleleaf forest), and this convergence occurred in functional types that spanned distinct geographic regions and climates.
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Affiliation(s)
- Savannah S Cooley
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York, NY, USA
| | - Joshua B Fisher
- Schmid College of Science and Technology, Chapman University, Orange, CA, USA.
| | - Gregory R Goldsmith
- Schmid College of Science and Technology, Chapman University, Orange, CA, USA
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22
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Díaz E, Adsuara JE, Martínez ÁM, Piles M, Camps-Valls G. Inferring causal relations from observational long-term carbon and water fluxes records. Sci Rep 2022; 12:1610. [PMID: 35102174 PMCID: PMC8803890 DOI: 10.1038/s41598-022-05377-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 12/14/2021] [Indexed: 11/28/2022] Open
Abstract
Land, atmosphere and climate interact constantly and at different spatial and temporal scales. In this paper we rely on causal discovery methods to infer spatial patterns of causal relations between several key variables of the carbon and water cycles: gross primary productivity, latent heat energy flux for evaporation, surface air temperature, precipitation, soil moisture and radiation. We introduce a methodology based on the convergent cross-mapping (CCM) technique. Despite its good performance in general, CCM is sensitive to (even moderate) noise levels and hyper-parameter selection. We present a robust CCM (RCCM) that relies on temporal bootstrapping decision scores and the derivation of more stringent cross-map skill scores. The RCCM method is combined with the information-geometric causal inference (IGCI) method to address the problem of strong and instantaneous variable coupling, another important and long-standing issue of CCM. The proposed methodology allows to derive spatially explicit global maps of causal relations between the involved variables and retrieve the underlying complexity of the interactions. Results are generally consistent with reported patterns and process understanding, and constitute a new way to quantify and understand carbon and water fluxes interactions.
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Affiliation(s)
- Emiliano Díaz
- Image Processing Laboratory (IPL), Universitat de València, Valencia, Spain.
| | - Jose E Adsuara
- Image Processing Laboratory (IPL), Universitat de València, Valencia, Spain
| | | | - María Piles
- Image Processing Laboratory (IPL), Universitat de València, Valencia, Spain
| | - Gustau Camps-Valls
- Image Processing Laboratory (IPL), Universitat de València, Valencia, Spain
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23
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Zhang Y, Keenan TF, Zhou S. Exacerbated drought impacts on global ecosystems due to structural overshoot. Nat Ecol Evol 2021; 5:1490-1498. [PMID: 34593995 PMCID: PMC8563399 DOI: 10.1038/s41559-021-01551-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 08/10/2021] [Indexed: 02/07/2023]
Abstract
Vegetation dynamics are affected not only by the concurrent climate but also by memory-induced lagged responses. For example, favourable climate in the past could stimulate vegetation growth to surpass the ecosystem carrying capacity, leaving an ecosystem vulnerable to climate stresses. This phenomenon, known as structural overshoot, could potentially contribute to worldwide drought stress and forest mortality but the magnitude of the impact is poorly known due to the dynamic nature of overshoot and complex influencing timescales. Here, we use a dynamic statistical learning approach to identify and characterize ecosystem structural overshoot globally and quantify the associated drought impacts. We find that structural overshoot contributed to around 11% of drought events during 1981-2015 and is often associated with compound extreme drought and heat, causing faster vegetation declines and greater drought impacts compared to non-overshoot related droughts. The fraction of droughts related to overshoot is strongly related to mean annual temperature, with biodiversity, aridity and land cover as secondary factors. These results highlight the large role vegetation dynamics play in drought development and suggest that soil water depletion due to warming-induced future increases in vegetation could cause more frequent and stronger overshoot droughts.
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Affiliation(s)
- Yao Zhang
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
- Department of Environmental Science, Policy and Management, UC Berkeley, Berkeley, CA, USA.
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China.
| | - Trevor F Keenan
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
- Department of Environmental Science, Policy and Management, UC Berkeley, Berkeley, CA, USA.
| | - Sha Zhou
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Environmental Science, Policy and Management, UC Berkeley, Berkeley, CA, USA
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
- State Key Laboratory of Earth Surface Processes and Resources Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, China
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24
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Diao C, Liu Y, Zhao L, Zhuo G, Zhang Y. Regional-scale vegetation-climate interactions on the Qinghai-Tibet Plateau. ECOL INFORM 2021. [DOI: 10.1016/j.ecoinf.2021.101413] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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25
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Zhu G, Wang X, Yang T, Su J, Qin Y, Wang S, Gillings M, Wang C, Ju F, Lan B, Liu C, Li H, Long XE, Wang X, Jetten MSM, Wang Z, Zhu YG. Air pollution could drive global dissemination of antibiotic resistance genes. THE ISME JOURNAL 2021; 15:270-281. [PMID: 32963346 PMCID: PMC7852678 DOI: 10.1038/s41396-020-00780-2] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 08/13/2020] [Accepted: 09/14/2020] [Indexed: 11/08/2022]
Abstract
Antibiotic-resistant pathogens pose a significant threat to human health. Several dispersal mechanisms have been described, but transport of both microbes and antibiotic resistance genes (ARGs) via atmospheric particles has received little attention as a pathway for global dissemination. These atmospheric particles can return to the Earth's surface via rain or snowfall, and thus promote long-distance spread of ARGs. However, the diversity and abundance of ARGs in fresh snow has not been studied and their potential correlation with particulate air pollution is not well explored. Here, we characterized ARGs in 44 samples of fresh snow from major cities in China, three in North America, and one in Europe, spanning a gradient from pristine to heavily anthropogenically influenced ecosystems. High-throughput qPCR analysis of ARGs and mobile genetic elements (MGEs) provided strong indications that dissemination of ARGs in fresh snow could be exacerbated by air pollution, severely increasing the health risks of both air pollution and ARGs. We showed that snowfall did effectively spread ARGs from point sources over the Earth surface. Together our findings urge for better pollution control to reduce the risk of global dissemination of antibiotic resistance genes.
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Affiliation(s)
- Guibing Zhu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
| | - Xiaomin Wang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Ting Yang
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China
| | - Jianqiang Su
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China
| | - Yu Qin
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Shanyun Wang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Michael Gillings
- ARC Centre of Excellence in Synthetic Biology, Department of Biological Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW, 2109, Australia
| | - Cheng Wang
- South China Sea Institution, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Feng Ju
- Environmental Microbiome and Biotechnology Laboratory (EMBLab), School of Engineering, Westlake University, Hangzhou, 310024, China
| | - Bangrui Lan
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Chunlei Liu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Hu Li
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China
| | - Xi-En Long
- School of Geographic Sciences, Nantong University, Nantong, 226007, China
| | - Xuming Wang
- Beijing Agro-Biotechnology Research Center, Beijing Academy of Agriculture and Forestry Sciences, Beijing, 100097, China
| | - Mike S M Jetten
- Department of Microbiology, Radboud University Nijmegen, 36525, AJ, Nijmegen, The Netherlands
| | - Zifa Wang
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China.
| | - Yong-Guan Zhu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
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26
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Long-term trend of precipitation stable isotopic compositions under global warming conditions. J Radioanal Nucl Chem 2020. [DOI: 10.1007/s10967-020-07246-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Sensitivity of Vegetation Growth to Precipitation in a Typical Afforestation Area in the Loess Plateau: Plant-Water Coupled Modelling. Ecol Modell 2020. [DOI: 10.1016/j.ecolmodel.2020.109128] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Systematic Orbital Geometry-Dependent Variations in Satellite Solar-Induced Fluorescence (SIF) Retrievals. REMOTE SENSING 2020. [DOI: 10.3390/rs12152346] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
While solar-induced fluorescence (SIF) shows promise as a remotely-sensed measurement directly related to photosynthesis, interpretation and validation of satellite-based SIF retrievals remains a challenge. SIF is influenced by the fraction of absorbed photosynthetically-active radiation at the canopy level that depends upon illumination geometry as well as the escape of SIF through the canopy that depends upon the viewing geometry. Several approaches to estimate the effects of sun-sensor geometry on satellite-based SIF have been proposed, and some have been implemented, most relying upon satellite reflectance measurements and/or other ancillary data sets. These approaches, designed to ultimately estimate intrinsic or physiological components of SIF related to photosynthesis, have not generally been applied globally to satellite measurements. Here, we examine in detail how SIF and related reflectance-based indices from wide swath polar orbiting satellites in low Earth orbit vary systematically due to the host satellite orbital characteristics. We compare SIF and reflectance-based parameters from the Global Ozone Mapping Experiment 2 (GOME-2) on the MetOp-B platform and from the TROPOspheric Monitoring Instrument (TROPOMI) on the Sentinel 5 Precursor satellite with a focus on high northern latitudes in summer where observations at similar geometries and local times occur. We show that GOME-2 and TROPOMI SIF observations agree nearly to within estimated uncertainties when they are compared at similar observing geometries. We show that the cross-track dependence of SIF normalized by PAR and related reflectance-based indices are highly correlated for dense canopies, but diverge substantially as the vegetation within a field-of-view becomes more sparse. This has implications for approaches that utilize reflectance measurements to help account for SIF geometrical dependences in satellite measurements. To further help interpret the GOME-2 and TROPOMI SIF observations, we simulated cross-track dependences of PAR normalized SIF and reflectance-based indices with the one dimensional Soil-Canopy Observation Photosynthesis and Energy fluxes (SCOPE) canopy radiative transfer model at sun–satellite geometries that occur across the wide swaths of these instruments and examine the geometrical dependencies of the various components (e.g., fraction of absorbed PAR, SIF yield, and escape of SIF from the canopy) of the observed SIF signal. The simulations show that most of the cross-track variations in SIF result from the escape of SIF through the scattering canopy and not the illumination.
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Paschalis A, Fatichi S, Zscheischler J, Ciais P, Bahn M, Boysen L, Chang J, De Kauwe M, Estiarte M, Goll D, Hanson PJ, Harper AB, Hou E, Kigel J, Knapp AK, Larsen KS, Li W, Lienert S, Luo Y, Meir P, Nabel JEMS, Ogaya R, Parolari AJ, Peng C, Peñuelas J, Pongratz J, Rambal S, Schmidt IK, Shi H, Sternberg M, Tian H, Tschumi E, Ukkola A, Vicca S, Viovy N, Wang YP, Wang Z, Williams K, Wu D, Zhu Q. Rainfall manipulation experiments as simulated by terrestrial biosphere models: Where do we stand? GLOBAL CHANGE BIOLOGY 2020; 26:3336-3355. [PMID: 32012402 DOI: 10.1111/gcb.15024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 01/22/2020] [Indexed: 06/10/2023]
Abstract
Changes in rainfall amounts and patterns have been observed and are expected to continue in the near future with potentially significant ecological and societal consequences. Modelling vegetation responses to changes in rainfall is thus crucial to project water and carbon cycles in the future. In this study, we present the results of a new model-data intercomparison project, where we tested the ability of 10 terrestrial biosphere models to reproduce the observed sensitivity of ecosystem productivity to rainfall changes at 10 sites across the globe, in nine of which, rainfall exclusion and/or irrigation experiments had been performed. The key results are as follows: (a) Inter-model variation is generally large and model agreement varies with timescales. In severely water-limited sites, models only agree on the interannual variability of evapotranspiration and to a smaller extent on gross primary productivity. In more mesic sites, model agreement for both water and carbon fluxes is typically higher on fine (daily-monthly) timescales and reduces on longer (seasonal-annual) scales. (b) Models on average overestimate the relationship between ecosystem productivity and mean rainfall amounts across sites (in space) and have a low capacity in reproducing the temporal (interannual) sensitivity of vegetation productivity to annual rainfall at a given site, even though observation uncertainty is comparable to inter-model variability. (c) Most models reproduced the sign of the observed patterns in productivity changes in rainfall manipulation experiments but had a low capacity in reproducing the observed magnitude of productivity changes. Models better reproduced the observed productivity responses due to rainfall exclusion than addition. (d) All models attribute ecosystem productivity changes to the intensity of vegetation stress and peak leaf area, whereas the impact of the change in growing season length is negligible. The relative contribution of the peak leaf area and vegetation stress intensity was highly variable among models.
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Affiliation(s)
- Athanasios Paschalis
- Department of Civil and Environmental Engineering, Imperial College London, London, UK
| | - Simone Fatichi
- Institute of Environmental Engineering, ETH Zurich, Zurich, Switzerland
| | - Jakob Zscheischler
- Climate and Environmental Physics, University of Bern, Bern, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l'Environnement, Gif sur Yvette, France
| | - Michael Bahn
- Department of Ecology, University of Innsbruck, Innsbruck, Austria
| | - Lena Boysen
- Max Planck Institute for Meteorology, Hamburg, Germany
| | - Jinfeng Chang
- Laboratoire des Sciences du Climat et de l'Environnement, Gif sur Yvette, France
| | - Martin De Kauwe
- ARC Centre of Excellence for Climate Extremes, University of New South Wales, Sydney, NSW, Australia
| | - Marc Estiarte
- CSIC, Global Ecology Unit CREAF-CSIC-UAB, Bellaterra, Catalonia, Spain
- CREAF, Cerdanyola del Vallès, Catalonia, Spain
| | - Daniel Goll
- Laboratoire des Sciences du Climat et de l'Environnement, Gif sur Yvette, France
- Department of Geography, University of Augsburg, Augsburg, Germany
| | - Paul J Hanson
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Anna B Harper
- Department of Mathematics, University of Exeter, Exeter, UK
| | - Enqing Hou
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, USA
| | - Jaime Kigel
- Institute for Plant Sciences and Genetics, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Alan K Knapp
- Graduate Degree Program in Ecology, Department of Biology, Colorado State University, Fort Collins, CO, USA
| | - Klaus S Larsen
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg C, Denmark
| | - Wei Li
- Laboratoire des Sciences du Climat et de l'Environnement, Gif sur Yvette, France
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, China
| | - Sebastian Lienert
- Climate and Environmental Physics, University of Bern, Bern, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
| | - Yiqi Luo
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, USA
| | - Patrick Meir
- Research School of Biology, Australian National University, Acton, ACT, Australia
- School of Geosciences, University of Edinburgh, Edinburgh, UK
| | | | - Romà Ogaya
- CSIC, Global Ecology Unit CREAF-CSIC-UAB, Bellaterra, Catalonia, Spain
- CREAF, Cerdanyola del Vallès, Catalonia, Spain
| | - Anthony J Parolari
- Department of Civil, Construction, and Environmental Engineering, Marquette University, Milwaukee, WI, USA
| | - Changhui Peng
- Department of Biology Sciences, University of Quebec at Montreal, Montreal, QC, Canada
| | - Josep Peñuelas
- CSIC, Global Ecology Unit CREAF-CSIC-UAB, Bellaterra, Catalonia, Spain
- CREAF, Cerdanyola del Vallès, Catalonia, Spain
| | - Julia Pongratz
- Department of Geography, Ludwig Maximilian University of Munich, Munchen, Germany
| | - Serge Rambal
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), UMR5175, CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, EPHE, Montpellier, France
| | - Inger K Schmidt
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg C, Denmark
| | - Hao Shi
- International Center for Climate and Global Change Research, School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL, USA
| | - Marcelo Sternberg
- School of Plant Sciences and Food Security, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Hanqin Tian
- International Center for Climate and Global Change Research, School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL, USA
| | - Elisabeth Tschumi
- Climate and Environmental Physics, University of Bern, Bern, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
| | - Anna Ukkola
- ARC Centre of Excellence for Climate Extremes, University of New South Wales, Sydney, NSW, Australia
| | - Sara Vicca
- Centre of Excellence PLECO (Plants and Ecosystems), Biology Department, University of Antwerp, Wilrijk, Belgium
| | - Nicolas Viovy
- Laboratoire des Sciences du Climat et de l'Environnement, Gif sur Yvette, France
| | - Ying-Ping Wang
- CSIRO Marine and Atmospheric Research and Centre for Australian Weather and Climate Research, Aspendale, Vic., Australia
| | - Zhuonan Wang
- International Center for Climate and Global Change Research, School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL, USA
| | | | - Donghai Wu
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Qiuan Zhu
- Center for Ecological Forecasting and Global Change, College of Forestry, Northwest A&F University, Xianyang, China
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30
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Damm A, Paul-Limoges E, Kükenbrink D, Bachofen C, Morsdorf F. Remote sensing of forest gas exchange: Considerations derived from a tomographic perspective. GLOBAL CHANGE BIOLOGY 2020; 26:2717-2727. [PMID: 31957162 DOI: 10.1111/gcb.15007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 12/17/2019] [Indexed: 06/10/2023]
Abstract
The global exchange of gas (CO2 , H2 O) and energy (sensible and latent heat) between forest ecosystems and the atmosphere is often assessed using remote sensing (RS) products. Although these products are essential in quantifying the spatial variability of forest-atmosphere exchanges, large uncertainties remain from a measurement bias towards top of canopy fluxes since optical RS data are not sensitive for the vertically integrated forest canopy. We hypothesize that a tomographic perspective opens new pathways to advance upscaling gas exchange processes from leaf to forest stands and larger scales. We suggest a 3D modelling environment comprising principles of ecohydrology and radiative transfer modelling with measurements of micrometeorological variables, leaf optical properties and forest structure, and assess 3D fields of net CO2 assimilation (An ) and transpiration (T) in a Swiss temperate forest canopy. 3D simulations were used to quantify uncertainties in gas exchange estimates inherent to RS approaches and model assumptions (i.e. a big-leaf approximation in modelling approaches). Our results reveal substantial 3D heterogeneity of forest gas exchange with top of canopy An and T being reduced by up to 98% at the bottom of the canopy. We show that a simplified use of RS causes uncertainties in estimated vertical gas exchange of up to 300% and that the spatial variation of gas exchange in the footprint of flux towers can exceed diurnal dynamics. We also demonstrate that big-leaf assumptions can cause uncertainties up to a factor of 10 for estimates of An and T. Concluding, we acknowledge the large potential of 3D assessments of gas exchange to unravelling the role of vertical variability and canopy structure in regulating forest-atmosphere gas and energy exchange. Such information allows to systematically link canopy with global scale controls on forest functioning and eventually enables advanced understanding of forest responses to environmental change.
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Affiliation(s)
- Alexander Damm
- Department of Geography, University of Zurich, Zurich, Switzerland
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | | | | | | | - Felix Morsdorf
- Department of Geography, University of Zurich, Zurich, Switzerland
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31
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Trends and Extremes of Drought Episodes in Vietnam Sub-Regions during 1980–2017 at Different Timescales. WATER 2020. [DOI: 10.3390/w12030813] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This study investigated the temporal occurrence of dry conditions in the seven climatic sub-regions of Vietnam during the 1980–2017 period. This assessment was performed using the Standardized Precipitation Evapotranspiration Index (SPEI) and the Standardized Precipitation Index (SPI) at 1 to 24 months timescales. Results show that the main periods of extreme drought occurred simultaneously throughout the country in 1992–1993 and 2003–2004, except for 2015–2016, when it was not identified in the southern region. In addition, a slight temporal lag was identified latitudinally (north–south) at the beginning of dry conditions, revealing the largest difference between the northern and southern regions. A positive trend in the time series of both indices (SPEI and SPI) prevailed in all sub-regions, with the SPEI minus SPI difference always being negative, suggesting the importance of temperature and evapotranspiration for this trend. Further detailed analyses were then performed using SPEI at 1-month and 12-months timescales for all climate sub-regions, as well as the main indicators to characterize duration and severity. Results show that the number of drought episodes did not vary much between regions, but they did vary in duration and severity at the annual scale. Moreover, changes in the soil root zone are largely associated with dry and wet conditions not only from season to season, but also in longer accumulation periods and more strongly in the northern regions of Vietnam. Indeed, a study of the most severe drought episodes also revealed the occurrence of negative anomalies of the root-soil moisture in the subsequent four or more months. Dynamic atmospheric conditions associated with the peak of most severe drought episodes show the crucial role of subsidence of dry air in the middle and high atmosphere, which prevents convection in the lower troposphere. Finally, the linkages between drought conditions in Vietnam and large-scale atmospheric and oceanic teleconnection patterns were revealed to be quite different among northern and southern sub-regions. During the positive phase of El Niño–Southern Oscillation (ENSO), drought episodes at different timescales were identified in the southern climate sub-regions, while the negative phase was associated with drought conditions in the northern regions.
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32
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Mohammed GH, Colombo R, Middleton EM, Rascher U, van der Tol C, Nedbal L, Goulas Y, Pérez-Priego O, Damm A, Meroni M, Joiner J, Cogliati S, Verhoef W, Malenovský Z, Gastellu-Etchegorry JP, Miller JR, Guanter L, Moreno J, Moya I, Berry JA, Frankenberg C, Zarco-Tejada PJ. Remote sensing of solar-induced chlorophyll fluorescence (SIF) in vegetation: 50 years of progress. REMOTE SENSING OF ENVIRONMENT 2019; 231:111177. [PMID: 33414568 PMCID: PMC7787158 DOI: 10.1016/j.rse.2019.04.030] [Citation(s) in RCA: 112] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Remote sensing of solar-induced chlorophyll fluorescence (SIF) is a rapidly advancing front in terrestrial vegetation science, with emerging capability in space-based methodologies and diverse application prospects. Although remote sensing of SIF - especially from space - is seen as a contemporary new specialty for terrestrial plants, it is founded upon a multi-decadal history of research, applications, and sensor developments in active and passive sensing of chlorophyll fluorescence. Current technical capabilities allow SIF to be measured across a range of biological, spatial, and temporal scales. As an optical signal, SIF may be assessed remotely using highly-resolved spectral sensors and state-of-the-art algorithms to distinguish the emission from reflected and/or scattered ambient light. Because the red to far-red SIF emission is detectable non-invasively, it may be sampled repeatedly to acquire spatio-temporally explicit information about photosynthetic light responses and steady-state behaviour in vegetation. Progress in this field is accelerating with innovative sensor developments, retrieval methods, and modelling advances. This review distills the historical and current developments spanning the last several decades. It highlights SIF heritage and complementarity within the broader field of fluorescence science, the maturation of physiological and radiative transfer modelling, SIF signal retrieval strategies, techniques for field and airborne sensing, advances in satellite-based systems, and applications of these capabilities in evaluation of photosynthesis and stress effects. Progress, challenges, and future directions are considered for this unique avenue of remote sensing.
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Affiliation(s)
| | - Roberto Colombo
- Remote Sensing of Environmental Dynamics Lab., University of Milano - Bicocca, Milan, Italy
| | | | - Uwe Rascher
- Forschungszentrum Jülich, Institute of Bio- and Geosciences, IBG-2: Plant Sciences, Jülich, Germany
| | - Christiaan van der Tol
- University of Twente, Faculty of Geo-Information Science and Earth Observation, Enschede, The Netherlands
| | - Ladislav Nedbal
- Forschungszentrum Jülich, Institute of Bio- and Geosciences, IBG-2: Plant Sciences, Jülich, Germany
| | - Yves Goulas
- CNRS, Laboratoire de Météorologie Dynamique (LMD), Ecole Polytechnique, Palaiseau, France
| | - Oscar Pérez-Priego
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Alexander Damm
- Department of Geography, University of Zurich, Zurich, Switzerland
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Duebendorf, Switzerland
| | - Michele Meroni
- European Commission, Joint Research Centre (JRC), Ispra (VA), Italy
| | - Joanna Joiner
- NASA/Goddard Space Flight Center, Greenbelt, Maryland, United States
| | - Sergio Cogliati
- Remote Sensing of Environmental Dynamics Lab., University of Milano - Bicocca, Milan, Italy
| | - Wouter Verhoef
- University of Twente, Faculty of Geo-Information Science and Earth Observation, Enschede, The Netherlands
| | - Zbyněk Malenovský
- Department of Geography and Spatial Sciences, School of Technology, Environments and Design, College of Sciences and Engineering, University of Tasmania, Hobart, Australia
| | | | - John R. Miller
- Department of Earth and Space Science and Engineering, York University, Toronto, Canada
| | - Luis Guanter
- German Research Center for Geosciences (GFZ), Remote Sensing Section, Potsdam, Germany
| | - Jose Moreno
- Department of Earth Physics and Thermodynamics, University of Valencia, Valencia, Spain
| | - Ismael Moya
- CNRS, Laboratoire de Météorologie Dynamique (LMD), Ecole Polytechnique, Palaiseau, France
| | - Joseph A. Berry
- Department of Global Ecology, Carnegie Institution of Washington, Stanford, California, United States
| | - Christian Frankenberg
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, United States
| | - Pablo J. Zarco-Tejada
- European Commission, Joint Research Centre (JRC), Ispra (VA), Italy
- Instituto de Agriculture Sostenible (IAS), Consejo Superior de Investigaciones Científicas (CSIC), Córdoba, Spain
- Department of Infrastructure Engineering, Melbourne School of Engineering, University of Melbourne, Melbourne, Victoria, Australia
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Melbourne, Victoria, Australia
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Anderegg WRL, Trugman AT, Bowling DR, Salvucci G, Tuttle SE. Plant functional traits and climate influence drought intensification and land-atmosphere feedbacks. Proc Natl Acad Sci U S A 2019; 116:14071-14076. [PMID: 31235581 PMCID: PMC6628816 DOI: 10.1073/pnas.1904747116] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The fluxes of energy, water, and carbon from terrestrial ecosystems influence the atmosphere. Land-atmosphere feedbacks can intensify extreme climate events like severe droughts and heatwaves because low soil moisture decreases both evaporation and plant transpiration and increases local temperature. Here, we combine data from a network of temperate and boreal eddy covariance towers, satellite data, plant trait datasets, and a mechanistic vegetation model to diagnose the controls of soil moisture feedbacks to drought. We find that climate and plant functional traits, particularly those related to maximum leaf gas exchange rate and water transport through the plant hydraulic continuum, jointly affect drought intensification. Our results reveal that plant physiological traits directly affect drought intensification and indicate that inclusion of plant hydraulic transport mechanisms in models may be critical for accurately simulating land-atmosphere feedbacks and climate extremes under climate change.
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Affiliation(s)
| | - Anna T Trugman
- School of Biological Sciences, University of Utah, Salt Lake City, UT 84112
| | - David R Bowling
- School of Biological Sciences, University of Utah, Salt Lake City, UT 84112
| | - Guido Salvucci
- Department of Earth and Environment, Boston University, Boston, MA 02215
| | - Samuel E Tuttle
- Department of Geology and Geography, Mount Holyoke College, South Hadley, MA 01075
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Impact of Large-Scale Afforestation on Surface Temperature: A Case Study in the Kubuqi Desert, Inner Mongolia Based on the WRF Model. FORESTS 2019. [DOI: 10.3390/f10050368] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Afforestation activities in the Kubuqi Desert, Inner Mongolia, China, have substantially increased tree and shrub coverage in this region. In this study, the response of the surface temperature to afforestation is simulated with the Weather Research and Forecasting model. The surface temperature changes are decomposed into contributions from the intrinsic surface biophysical effect and atmospheric feedback, using the theory of intrinsic biophysical mechanism. The effect of afforestation on the surface temperature is 1.34 K, −0.48 K, 2.09 K and 0.22 K for the summer daytime, the summer nighttime, the winter daytime and the winter nighttime, respectively, for the grid cells that have experienced conversion from bare soil to shrub. The corresponding domain mean values are 0.15 K, −0.2 K, 0.67 K, and 0.06 K. The seasonal variation of surface temperature change is mainly caused by changes in roughness and Bowen ratio. In the daytime, the surface temperature changes are dominated by the biophysical effect, with albedo change being the main biophysical factor. In the nighttime, the biophysical effect (mainly associated with roughness change) and the atmospheric feedback (mainly associated with change in the background air temperature) contribute similar amounts to the surface temperature changes. We conclude that the atmospheric feedback can amplify the influence of the surface biophysical effect, especially in the nighttime.
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35
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Berger S, Bliefernicht J, Linstädter A, Canak K, Guug S, Heinzeller D, Hingerl L, Mauder M, Neidl F, Quansah E, Salack S, Steinbrecher R, Kunstmann H. The impact of rain events on CO 2 emissions from contrasting land use systems in semi-arid West African savannas. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 647:1478-1489. [PMID: 30180353 DOI: 10.1016/j.scitotenv.2018.07.397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Revised: 07/26/2018] [Accepted: 07/27/2018] [Indexed: 06/08/2023]
Abstract
In the future the Sudanian savanna - one of West Africa's high-potential "bread baskets" - will likely face shorter rainy seasons with more extreme rains and droughts. That could have serious impacts on the vegetation and its carbon dioxide (CO2) exchange with potentially increasing CO2 emissions accelerating climate warming. Understanding how the CO2 fluxes in this area respond to environmental variables, in particular rain events, is essential, but available data are scarce. In this study, we monitored net ecosystem exchange (NEE) of CO2, rainfall and other environmental parameters during four years at three savannas. Savannas were characterized by different vegetation due to different land use: i) woody and nearly pristine, ii) mixture of cropland and grassland and iii) intensive grazing. The impact of rain events on CO2 exchange for these contrasting ecosystems were analyzed for single rain events (short-term) and on a yearly time scale (long-term) using three eddy covariance towers. We found that the woody pristine savanna site was a prominent sink of CO2 (-864 to -1299 g CO2 m-2 y-1) while the degraded sites were net CO2 sources (118 to 605 g CO2 m-2 y-1) with a complicated relation with annual rainfall amounts. The NEE responses to single rain events revealed that daytime rain systematically decreased the sink strengths at all sites, which might be associated with decreased light availability. At the degraded sites, additional factors increasing CO2 losses were rain duration and dry spell length. The observed patterns of immediate CO2 flux responses to rainfall at differently used savannas indicate strong internal feedbacks between vegetation and land use changes and raise the question whether the CO2 sink strengths might be overestimated with possible implications for global CO2 budgets. Sustainable adaptation strategies need to be developed for West Africa.
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Affiliation(s)
- Sina Berger
- Institute for Meteorology and Climate Research, Karlsruhe Institute of Technology, Campus Alpin, Garmisch-Partenkirchen, Germany; Institute of Geography, University of Augsburg, Augsburg, Germany.
| | - Jan Bliefernicht
- Institute of Geography, University of Augsburg, Augsburg, Germany
| | - Anja Linstädter
- Range Ecology and Range Management Group, Botanical Institute, University of Cologne, Germany; Institute of Crop Science and Resource Conservation, University of Bonn, Germany
| | - Kristijan Canak
- Range Ecology and Range Management Group, Botanical Institute, University of Cologne, Germany; Department of Geography, University of Bonn, Germany
| | - Samuel Guug
- West African Science Service Centre on Climate Change and Adapted Land Use, WASCAL Competence Centre, Burkina Faso, Bolgatanga-Vea Watershed, Ghana
| | - Dominikus Heinzeller
- Institute for Meteorology and Climate Research, Karlsruhe Institute of Technology, Campus Alpin, Garmisch-Partenkirchen, Germany; Institute of Geography, University of Augsburg, Augsburg, Germany; University of Colorado Boulder, Cooperative Institute for Research in Environmental Sciences, NOAA/OAR/ESRL/Global Systems Division, Boulder, CO, USA
| | - Luitpold Hingerl
- Institute of Geography, University of Augsburg, Augsburg, Germany
| | - Matthias Mauder
- Institute for Meteorology and Climate Research, Karlsruhe Institute of Technology, Campus Alpin, Garmisch-Partenkirchen, Germany
| | - Frank Neidl
- Institute for Meteorology and Climate Research, Karlsruhe Institute of Technology, Campus Alpin, Garmisch-Partenkirchen, Germany
| | - Emmanuel Quansah
- Department of Physics, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Seyni Salack
- West African Science Service Centre on Climate Change and Adapted Land Use, WASCAL Competence Centre, Burkina Faso
| | - Rainer Steinbrecher
- Institute for Meteorology and Climate Research, Karlsruhe Institute of Technology, Campus Alpin, Garmisch-Partenkirchen, Germany
| | - Harald Kunstmann
- Institute for Meteorology and Climate Research, Karlsruhe Institute of Technology, Campus Alpin, Garmisch-Partenkirchen, Germany; Institute of Geography, University of Augsburg, Augsburg, Germany
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Miralles DG, Gentine P, Seneviratne SI, Teuling AJ. Land-atmospheric feedbacks during droughts and heatwaves: state of the science and current challenges. Ann N Y Acad Sci 2019; 1436:19-35. [PMID: 29943456 PMCID: PMC6378599 DOI: 10.1111/nyas.13912] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 05/29/2018] [Accepted: 06/01/2018] [Indexed: 11/30/2022]
Abstract
Droughts and heatwaves cause agricultural loss, forest mortality, and drinking water scarcity, especially when they occur simultaneously as combined events. Their predicted increase in recurrence and intensity poses serious threats to future food security. Still today, the knowledge of how droughts and heatwaves start and evolve remains limited, and so does our understanding of how climate change may affect them. Droughts and heatwaves have been suggested to intensify and propagate via land-atmosphere feedbacks. However, a global capacity to observe these processes is still lacking, and climate and forecast models are immature when it comes to representing the influences of land on temperature and rainfall. Key open questions remain in our goal to uncover the real importance of these feedbacks: What is the impact of the extreme meteorological conditions on ecosystem evaporation? How do these anomalies regulate the atmospheric boundary layer state (event self-intensification) and contribute to the inflow of heat and moisture to other regions (event self-propagation)? Can this knowledge on the role of land feedbacks, when available, be exploited to develop geo-engineering mitigation strategies that prevent these events from aggravating during their early stages? The goal of our perspective is not to present a convincing answer to these questions, but to assess the scientific progress to date, while highlighting new and innovative avenues to keep advancing our understanding in the future.
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Affiliation(s)
- Diego G. Miralles
- Laboratory of Hydrology and Water ManagementGhent UniversityGhentBelgium
| | - Pierre Gentine
- Earth and Environmental EngineeringColumbia UniversityNew YorkNew York
| | | | - Adriaan J. Teuling
- Hydrology and Quantitative Water Management GroupWageningen University and ResearchWageningenthe Netherlands
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Green JK, Seneviratne SI, Berg AM, Findell KL, Hagemann S, Lawrence DM, Gentine P. Large influence of soil moisture on long-term terrestrial carbon uptake. Nature 2019; 565:476-479. [PMID: 30675043 PMCID: PMC6355256 DOI: 10.1038/s41586-018-0848-x] [Citation(s) in RCA: 110] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 11/21/2018] [Indexed: 11/28/2022]
Abstract
Although the terrestrial biosphere absorbs about 25 per cent of anthropogenic carbon dioxide (CO2) emissions, the rate of land carbon uptake remains highly uncertain, leading to uncertainties in climate projections1,2. Understanding the factors that limit or drive land carbon storage is therefore important for improving climate predictions. One potential limiting factor for land carbon uptake is soil moisture, which can reduce gross primary production through ecosystem water stress3,4, cause vegetation mortality5 and further exacerbate climate extremes due to land-atmosphere feedbacks6. Previous work has explored the impact of soil-moisture availability on past carbon-flux variability3,7,8. However, the influence of soil-moisture variability and trends on the long-term carbon sink and the mechanisms responsible for associated carbon losses remain uncertain. Here we use the data output from four Earth system models9 from a series of experiments to analyse the responses of terrestrial net biome productivity to soil-moisture changes, and find that soil-moisture variability and trends induce large CO2 fluxes (about two to three gigatons of carbon per year; comparable with the land carbon sink itself1) throughout the twenty-first century. Subseasonal and interannual soil-moisture variability generate CO2 as a result of the nonlinear response of photosynthesis and net ecosystem exchange to soil-water availability and of the increased temperature and vapour pressure deficit caused by land-atmosphere interactions. Soil-moisture variability reduces the present land carbon sink, and its increase and drying trends in several regions are expected to reduce it further. Our results emphasize that the capacity of continents to act as a future carbon sink critically depends on the nonlinear response of carbon fluxes to soil moisture and on land-atmosphere interactions. This suggests that the increasing trend in carbon uptake rate may not be sustained past the middle of the century and could result in accelerated atmospheric CO2 growth.
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Affiliation(s)
- Julia K Green
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA.
| | - Sonia I Seneviratne
- Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
| | - Alexis M Berg
- Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ, USA
| | | | - Stefan Hagemann
- Institute of Coastal Research, Helmholtz-Zentrum Geesthacht, Geesthacht, Germany
| | - David M Lawrence
- Climate and Global Dynamics Laboratory, Terrestrial Sciences, National Center for Atmospheric Research, Boulder, CO, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
- The Earth Institute, Columbia University, New York, NY, USA
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38
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Satellite and In Situ Observations for Advancing Global Earth Surface Modelling: A Review. REMOTE SENSING 2018. [DOI: 10.3390/rs10122038] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In this paper, we review the use of satellite-based remote sensing in combination with in situ data to inform Earth surface modelling. This involves verification and optimization methods that can handle both random and systematic errors and result in effective model improvement for both surface monitoring and prediction applications. The reasons for diverse remote sensing data and products include (i) their complementary areal and temporal coverage, (ii) their diverse and covariant information content, and (iii) their ability to complement in situ observations, which are often sparse and only locally representative. To improve our understanding of the complex behavior of the Earth system at the surface and sub-surface, we need large volumes of data from high-resolution modelling and remote sensing, since the Earth surface exhibits a high degree of heterogeneity and discontinuities in space and time. The spatial and temporal variability of the biosphere, hydrosphere, cryosphere and anthroposphere calls for an increased use of Earth observation (EO) data attaining volumes previously considered prohibitive. We review data availability and discuss recent examples where satellite remote sensing is used to infer observable surface quantities directly or indirectly, with particular emphasis on key parameters necessary for weather and climate prediction. Coordinated high-resolution remote-sensing and modelling/assimilation capabilities for the Earth surface are required to support an international application-focused effort.
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Zhao Y, Wang X, Novillo CJ, Arrogante-Funes P, Vázquez-Jiménez R, Maestre FT. Albedo estimated from remote sensing correlates with ecosystem multifunctionality in global drylands. JOURNAL OF ARID ENVIRONMENTS 2018; 157:116-123. [PMID: 30174356 PMCID: PMC6112417 DOI: 10.1016/j.jaridenv.2018.05.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Monitoring ecosystem functioning is a significant step towards detecting changes in ecosystem attributes that could be linked to land degradation and desertification in drylands worldwide. Remote sensing-based vegetation indices (VIs) and land surface albedo are two favorite indicators to monitor desertification process due to their close relationship with ecosystem status and to their increasing applicability over multiple spatiotemporal scales. While VIs are routinely used to monitor ecosystem attributes and functions such as vegetation cover and productivity, no previous study has evaluated whether remote sensing-measured albedo is related to the simultaneous provision of multiple ecosystem functions (multifunctionality) in global drylands. In this study, we evaluated the correlation of six albedo metrics (shortwave black-sky albedo, shortwave white-sky albedo, visible black-sky albedo, visible white-sky albedo, near-infrared black-sky albedo and near-infrared white-sky albedo) and two VIs (Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI)) with multifunctionality indices related to carbon, nitrogen and phosphorus cycling measured in 61 dryland ecosystems from all continents except Antarctica. We found a negative relationship between land surface albedo and multifunctionality. Black-sky albedo had a stronger correlation with multifunctionality than white-sky albedo. Visible black-sky albedo showed the strongest correlation with multifunctionality (MUL, -0.314), as well as with functions related to carbon (CCY, -0.216) and nitrogen cycling (NCY, -0.410), while near-infrared (-0.339) and shortwave black-sky albedo (-0.325) showed stronger correlations with functions related to phosphorus cycling (PCY) than visible black-sky albedo (-0.233) did. VIs showed significant positive correlations with MUL, CCY, and NCY, and the magnitudes were higher than those observed between albedo metrics and the multifunctionality indices. However, VIs were not correlated with PCY, which had significant correlations with both shortwave and near-infrared albedo. Though the magnitudes of the correlations observed were not high, which may result from the wide variability in soil and vegetation types in our dataset, our findings indicate that remotely sensed albedo correlates to multifunctionality, which has been linked to alternative states in global drylands. As such, albedo has the potential to monitor changes in dryland ecosystem functioning, which can inform us about the onset of desertification in these areas.
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Affiliation(s)
- Yanchuang Zhao
- Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, 100094 Beijing, China
- University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Xinyuan Wang
- Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, 100094 Beijing, China
| | - Carlos J. Novillo
- Departamento de Tecnología Química y Ambiental, Universidad Rey Juan Carlos, C/ Tulipán s/n, 28933 Móstoles, Spain
| | - Patricia Arrogante-Funes
- Departamento de Tecnología Química y Ambiental, Universidad Rey Juan Carlos, C/ Tulipán s/n, 28933 Móstoles, Spain
| | - René Vázquez-Jiménez
- Cuerpo Académico UAGro CA-93 Riesgos Naturales y Geotecnología, Universidad Autónoma de Guerrero, Av/Lázaro Cárdenas s/n, CU, Chilpancingo, Guerrero 39070, México
| | - Fernando T. Maestre
- Departamento de Biología y Geología, Física y Química Inorgánica, Universidad Rey Juan Carlos, C/ Tulipán s/n, 28933 Móstoles, Spain
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Peters W, van der Velde IR, van Schaik E, Miller JB, Ciais P, Duarte HF, van der Laan-Luijkx IT, van der Molen MK, Scholze M, Schaefer K, Vidale PL, Verhoef A, Wårlind D, Zhu D, Tans PP, Vaughn B, White JW. Increased water-use efficiency and reduced CO 2 uptake by plants during droughts at a continental-scale. NATURE GEOSCIENCE 2018; 11:744-748. [PMID: 30319710 PMCID: PMC6179136 DOI: 10.1038/s41561-018-0212-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 07/17/2018] [Indexed: 05/06/2023]
Abstract
Severe droughts in the Northern Hemisphere cause widespread decline of agricultural yield, reduction of forest carbon uptake, and increased CO2 growth rates in the atmosphere. Plants respond to droughts by partially closing their stomata to limit their evaporative water loss, at the expense of carbon uptake by photosynthesis. This trade-off maximizes their water-use efficiency, as measured for many individual plants under laboratory conditions and field experiments. Here we analyze the 13C/12C stable isotope ratio in atmospheric CO2 (reported as δ13C) to provide new observational evidence of the impact of droughts on the water-use efficiency across areas of millions of km2 and spanning one decade of recent climate variability. We find strong and spatially coherent increases in water-use efficiency along with widespread reductions of net carbon uptake over the Northern Hemisphere during severe droughts that affected Europe, Russia, and the United States in 2001-2011. The impact of those droughts on water-use efficiency and carbon uptake by vegetation is substantially larger than simulated by the land-surface schemes of six state-of-the-art climate models. This suggests that drought induced carbon-climate feedbacks may be too small in these models and improvements to their vegetation dynamics using stable isotope observations can help to improve their drought response.
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Affiliation(s)
- Wouter Peters
- Environmental Sciences Group, Wageningen University, Wageningen, The Netherlands
- University of Groningen, Centre for Isotope Research, Groningen, The Netherlands
| | - Ivar R. van der Velde
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, United States
- Global Monitoring Division, NOAA Earth System Research Laboratory, Boulder, CO, United States
| | - Erik van Schaik
- Environmental Sciences Group, Wageningen University, Wageningen, The Netherlands
| | - John B. Miller
- Global Monitoring Division, NOAA Earth System Research Laboratory, Boulder, CO, United States
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l’Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Gif sur Yvette, France
| | - Henrique F. Duarte
- Dept. of Atm. Sciences, University of Utah, Salt Lake City, Utah, United States
| | | | | | - Marko Scholze
- Dept. of Physical Geography and Ecosystem Science, Lund University, Lund, Sweden
| | - Kevin Schaefer
- National Snow and Ice Data Center, University of Colorado, Boulder, CO, United States
| | | | - Anne Verhoef
- Dept. of Geography and Environmental Science, University of Reading, Reading, UK
| | - David Wårlind
- Dept. of Physical Geography and Ecosystem Science, Lund University, Lund, Sweden
| | - Dan Zhu
- Laboratoire des Sciences du Climat et de l’Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Gif sur Yvette, France
| | - Pieter P. Tans
- Global Monitoring Division, NOAA Earth System Research Laboratory, Boulder, CO, United States
| | - Bruce Vaughn
- Institute for Arctic and Alpine Research, University of Colorado, Boulder, CO, United States
| | - James W.C. White
- Institute for Arctic and Alpine Research, University of Colorado, Boulder, CO, United States
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42
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Damm A, Paul-Limoges E, Haghighi E, Simmer C, Morsdorf F, Schneider FD, van der Tol C, Migliavacca M, Rascher U. Remote sensing of plant-water relations: An overview and future perspectives. JOURNAL OF PLANT PHYSIOLOGY 2018; 227:3-19. [PMID: 29735177 DOI: 10.1016/j.jplph.2018.04.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 04/16/2018] [Accepted: 04/17/2018] [Indexed: 05/27/2023]
Abstract
Vegetation is a highly dynamic component of the Earth surface and substantially alters the water cycle. Particularly the process of oxygenic plant photosynthesis determines vegetation connecting the water and carbon cycle and causing various interactions and feedbacks across Earth spheres. While vegetation impacts the water cycle, it reacts to changing water availability via functional, biochemical and structural responses. Unravelling the resulting complex feedbacks and interactions between the plant-water system and environmental change is essential for any modelling approaches and predictions, but still insufficiently understood due to currently missing observations. We hypothesize that an appropriate cross-scale monitoring of plant-water relations can be achieved by combined observational and modelling approaches. This paper reviews suitable remote sensing approaches to assess plant-water relations ranging from pure observational to combined observational-modelling approaches. We use a combined energy balance and radiative transfer model to assess the explanatory power of pure observational approaches focussing on plant parameters to estimate plant-water relations, followed by an outline for a more effective use of remote sensing by their integration into soil-plant-atmosphere continuum (SPAC) models. We apply a mechanistic model simulating water movement in the SPAC to reveal insight into the complexity of relations between soil, plant and atmospheric parameters, and thus plant-water relations. We conclude that future research should focus on strategies combining observations and mechanistic modelling to advance our knowledge on the interplay between the plant-water system and environmental change, e.g. through plant transpiration.
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Affiliation(s)
- A Damm
- Department of Geography, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland; Department of Surface Waters - Research and Management, Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland.
| | - E Paul-Limoges
- Department of Geography, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland; Department of Surface Waters - Research and Management, Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
| | - E Haghighi
- Department of Geography, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland; Department of Surface Waters - Research and Management, Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland; Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139, USA
| | - C Simmer
- University Bonn, Meteorological Institute, Auf dem Huegel 20, D-53121 Bonn, Germany
| | - F Morsdorf
- Department of Geography, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - F D Schneider
- Department of Geography, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - C van der Tol
- University of Twente, Faculty of Geo-Information Science and Earth Observation (ITC), P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - M Migliavacca
- Max Planck Institute for Biogeochemistry, Department Biogeochemical Integration, Hans-Knoell-Strasse 10, 07745 Jena, Germany
| | - U Rascher
- Institute of Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
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43
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Indications of Surface and Sub-Surface Hydrologic Properties from SMAP Soil Moisture Retrievals. HYDROLOGY 2018. [DOI: 10.3390/hydrology5030036] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Variability and covariability of land properties (soil, vegetation and subsurface geology) and remotely sensed soil moisture over the southeast and south-central U.S. are assessed. The goal is to determine whether satellite soil moisture memory contains information regarding land properties, especially the distribution karst formations below the active soil column that have a bearing on land-atmosphere feedbacks. Local (within a few tens of km) statistics of land states and soil moisture are considered to minimize the impact of climatic variations, and the local statistics are then correlated across the domain to illuminate significant relationships. There is a clear correspondence between soil moisture memory and many land properties including karst distribution. This has implications for distributed land surface modeling, which has not considered preferential water flows through geologic formations. All correspondences are found to be strongest during spring and fall, and weak during summer, when atmospheric moisture demand appears to dominate soil moisture variability. While there are significant relationships between remotely-sensed soil moisture variability and land properties, it will be a challenge to use satellite data for terrestrial parameter estimation as there is often a great deal of correlation among soil, vegetation and karst property distributions.
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44
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Detection of Spatiotemporal Extreme Changes in Atmospheric CO2 Concentration Based on Satellite Observations. REMOTE SENSING 2018. [DOI: 10.3390/rs10060839] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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45
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Lemordant L, Gentine P, Swann AS, Cook BI, Scheff J. Critical impact of vegetation physiology on the continental hydrologic cycle in response to increasing CO 2. Proc Natl Acad Sci U S A 2018; 115:4093-4098. [PMID: 29610293 PMCID: PMC5910855 DOI: 10.1073/pnas.1720712115] [Citation(s) in RCA: 129] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Predicting how increasing atmospheric CO2 will affect the hydrologic cycle is of utmost importance for a range of applications ranging from ecological services to human life and activities. A typical perspective is that hydrologic change is driven by precipitation and radiation changes due to climate change, and that the land surface will adjust. Using Earth system models with decoupled surface (vegetation physiology) and atmospheric (radiative) CO2 responses, we here show that the CO2 physiological response has a dominant role in evapotranspiration and evaporative fraction changes and has a major effect on long-term runoff compared with radiative or precipitation changes due to increased atmospheric CO2 This major effect is true for most hydrological stress variables over the largest fraction of the globe, except for soil moisture, which exhibits a more nonlinear response. This highlights the key role of vegetation in controlling future terrestrial hydrologic response and emphasizes that the carbon and water cycles are intimately coupled over land.
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Affiliation(s)
- Léo Lemordant
- Earth and Environmental Engineering Department, Columbia University, New York, NY 10027;
| | - Pierre Gentine
- Earth and Environmental Engineering Department, Columbia University, New York, NY 10027;
- Earth Institute, Columbia University, New York, NY 10025
| | - Abigail S Swann
- Department of Atmospheric Sciences, University of Washington, Seattle, WA 98105
- Department of Biology, University of Washington, Seattle, WA 98195
| | - Benjamin I Cook
- NASA Goddard Institute for Space Studies, New York, NY 10025
- Ocean and Climate Physics, Lamont-Doherty Earth Observatory, Palisades, NY 10964
| | - Jacob Scheff
- Department of Geography & Earth Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223
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Gentine P, Alemohammad SH. Reconstructed Solar-Induced Fluorescence: A Machine Learning Vegetation Product Based on MODIS Surface Reflectance to Reproduce GOME-2 Solar-Induced Fluorescence. GEOPHYSICAL RESEARCH LETTERS 2018; 45:3136-3146. [PMID: 30034047 PMCID: PMC6049983 DOI: 10.1002/2017gl076294] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Revised: 03/09/2018] [Accepted: 03/13/2018] [Indexed: 05/19/2023]
Abstract
Solar-induced fluorescence (SIF) observations from space have resulted in major advancements in estimating gross primary productivity (GPP). However, current SIF observations remain spatially coarse, infrequent, and noisy. Here we develop a machine learning approach using surface reflectances from Moderate Resolution Imaging Spectroradiometer (MODIS) channels to reproduce SIF normalized by clear sky surface irradiance from the Global Ozone Monitoring Experiment-2 (GOME-2). The resulting product is a proxy for ecosystem photosynthetically active radiation absorbed by chlorophyll (fAPARCh). Multiplying this new product with a MODIS estimate of photosynthetically active radiation provides a new MODIS-only reconstruction of SIF called Reconstructed SIF (RSIF). RSIF exhibits much higher seasonal and interannual correlation than the original SIF when compared with eddy covariance estimates of GPP and two reference global GPP products, especially in dry and cold regions. RSIF also reproduces intense productivity regions such as the U.S. Corn Belt contrary to typical vegetation indices and similarly to SIF.
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Affiliation(s)
- P. Gentine
- Department of Earth and Environmental EngineeringColumbia UniversityNew YorkNYUSA
| | - S. H. Alemohammad
- Department of Earth and Environmental EngineeringColumbia UniversityNew YorkNYUSA
- Radiant.EarthWashingtonDCUSA
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47
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Comprehensive Evaluation of Machine Learning Techniques for Estimating the Responses of Carbon Fluxes to Climatic Forces in Different Terrestrial Ecosystems. ATMOSPHERE 2018. [DOI: 10.3390/atmos9030083] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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48
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Yu Y, Notaro M, Wang F, Mao J, Shi X, Wei Y. Observed positive vegetation-rainfall feedbacks in the Sahel dominated by a moisture recycling mechanism. Nat Commun 2017; 8:1873. [PMID: 29187740 PMCID: PMC5707399 DOI: 10.1038/s41467-017-02021-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 11/01/2017] [Indexed: 11/09/2022] Open
Abstract
Classic, model-based theory of land-atmosphere interactions across the Sahel promote positive vegetation-rainfall feedbacks dominated by surface albedo mechanism. However, neither the proposed positive vegetation-rainfall feedback nor its underlying albedo mechanism has been convincingly demonstrated using observational data. Here, we present observational evidence for the region's proposed positive vegetation-rainfall feedback on the seasonal to interannual time scale, and find that it is associated with a moisture recycling mechanism, rather than the classic albedo-based mechanism. Positive anomalies of remotely sensed vegetation greenness across the Sahel during the late and post-monsoon periods favor enhanced evapotranspiration, precipitable water, convective activity and rainfall, indicative of amplified moisture recycling. The identified modest low-level cooling and anomalous atmospheric subsidence in response to positive vegetation greenness anomalies are counter to the responses expected through the classic vegetation-albedo feedback mechanism. The observational analysis further reveals enhanced dust emissions in response to diminished Sahel vegetation growth, potentially contributing to the positive vegetation-rainfall feedback.
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Affiliation(s)
- Yan Yu
- Nelson Institute Center for Climatic Research, University of Wisconsin-Madison, Madison, WI, 53706, USA.
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, 91109, USA.
| | - Michael Notaro
- Nelson Institute Center for Climatic Research, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Fuyao Wang
- Nelson Institute Center for Climatic Research, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Jiafu Mao
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Xiaoying Shi
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Yaxing Wei
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
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