Grazing and ecosystem service delivery in global drylands

Grazing represents the most extensive use of land worldwide. Yet its impacts on ecosystem services remain uncertain because pervasive interactions between grazing pressure, climate, soil properties, and biodiversity may occur but have never been addressed simultaneously. Using a standardized survey at 98 sites across six continents, we show that interactions between grazing pressure, climate, soil, and biodiversity are critical to explain the delivery of fundamental ecosystem services across drylands worldwide. Increasing grazing pressure reduced ecosystem service delivery in warmer and speciespoor drylands, whereas positive effects of grazing were observed in colder and species-rich areas. Considering interactions between grazing and local abiotic and biotic factors is key for understanding the fate of dryland ecosystems under climate change and increasing human pressure.Estación Experimental Agropecuaria BarilocheFil: Maestre, Fernando Tomas. Universidad de Alicante. Instituto Multidisciplinar para el Estudio del Medio Ramón Margalef; EspañaFil: Gaitan, Juan Jose. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Area de Recusos Naturales. Laboratorio de Teledetección; ArgentinaFil: Gaitan, Juan Jose. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Suelos; ArgentinaFil: Gaitan, Juan Jose. Universidad Nacional de Luján. Departamento de Tecnología; ArgentinaFil: Gaitan, Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aramayo, Maria Valeria Del Luján. Instituto Nacional de Tecnologia Agropecuaria (INTA). Estacion Experimental Agropecuaria Bariloche. Area Recursos Naturales; ArgentinaFil: Ahumada, Rodrigo José. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Catamarca; ArgentinaFil: Ferrante, Daniela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; ArgentinaFil: Ferrante, Daniela. Universidad Nacional de la Patagonia Autral; ArgentinaFil: Leder, Cintia V. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Leder, Cintia V. Universidad Nacional de Rio Negro; ArgentinaFil: Oliva, Gabriel Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; ArgentinaFil: Oliva, Gabriel Esteban. Universidad Nacional de la Patagonia Austral; ArgentinaFil: Bran, Donaldo Eduardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estacion Experimental Agropecuaria Bariloche. Area de Recursos Naturales; ArgentinaFil: Gross, Nicolas. Université Clermont Auvergne; Franci

Extreme drought impacts have been underestimated in grasslands and shrublands globally.

Climate change is increasing the frequency and severity of short-term (~1 y) drought events-the most common duration of drought-globally. Yet the impact of this intensification of drought on ecosystem functioning remains poorly resolved. This is due in part to the widely disparate approaches ecologists have employed to study drought, variation in the severity and duration of drought studied, and differences among ecosystems in vegetation, edaphic and climatic attributes that can mediate drought impacts. To overcome these problems and better identify the factors that modulate drought responses, we used a coordinated distributed experiment to quantify the impact of short-term drought on grassland and shrubland ecosystems. With a standardized approach, we imposed ~a single year of drought at 100 sites on six continents. Here we show that loss of a foundational ecosystem function-aboveground net primary production (ANPP)-was 60% greater at sites that experienced statistically extreme drought (1-in-100-y event) vs. those sites where drought was nominal (historically more common) in magnitude (35% vs. 21%, respectively). This reduction in a key carbon cycle process with a single year of extreme drought greatly exceeds previously reported losses for grasslands and shrublands. Our global experiment also revealed high variability in drought response but that relative reductions in ANPP were greater in drier ecosystems and those with fewer plant species. Overall, our results demonstrate with unprecedented rigor that the global impacts of projected increases in drought severity have been significantly underestimated and that drier and less diverse sites are likely to be most vulnerable to extreme drought

Grazing and ecosystem service delivery in global drylands

Grazing represents the most extensive use of land worldwide. Yet its impacts on ecosystem services remain uncertain because pervasive interactions between grazing pressure, climate, soil properties, and biodiversity may occur but have never been addressed simultaneously. Using a standardized survey at 98 sites across six continents, we show that interactions between grazing pressure, climate, soil, and biodiversity are critical to explain the delivery of fundamental ecosystem services across drylands worldwide. Increasing grazing pressure reduced ecosystem service delivery in warmer and species-poor drylands, whereas positive effects of grazing were observed in colder and species-rich areas. Considering interactions between grazing and local abiotic and biotic factors is key for understanding the fate of dryland ecosystems under climate change and increasing human pressure

Extreme drought impacts have been underestimated in grasslands and shrublands globally

Altres Ajuts: Fundación Ramón Areces grant CIVP20A6621Climate change is increasing the frequency and severity of short-term (~1 y) drought events-the most common duration of drought-globally. Yet the impact of this intensification of drought on ecosystem functioning remains poorly resolved. This is due in part to the widely disparate approaches ecologists have employed to study drought, variation in the severity and duration of drought studied, and differences among ecosystems in vegetation, edaphic and climatic attributes that can mediate drought impacts. To overcome these problems and better identify the factors that modulate drought responses, we used a coordinated distributed experiment to quantify the impact of short-term drought on grassland and shrubland ecosystems. With a standardized approach, we imposed ~a single year of drought at 100 sites on six continents. Here we show that loss of a foundational ecosystem function-aboveground net primary production (ANPP)-was 60% greater at sites that experienced statistically extreme drought (1-in-100-y event) vs. those sites where drought was nominal (historically more common) in magnitude (35% vs. 21%, respectively). This reduction in a key carbon cycle process with a single year of extreme drought greatly exceeds previously reported losses for grasslands and shrublands. Our global experiment also revealed high variability in drought response but that relative reductions in ANPP were greater in drier ecosystems and those with fewer plant species. Overall, our results demonstrate with unprecedented rigor that the global impacts of projected increases in drought severity have been significantly underestimated and that drier and less diverse sites are likely to be most vulnerable to extreme drought

Data and R code from "Grazing and ecosystem service delivery in global drylands"

There are two zip files with the data and R scripts used in the article "Grazing and ecosystem service delivery in global drylands". The file "Main_Data_code.zip" contains the data and R code used in the main analyses of the paper. These data also include the location and major environmental characteristics of the plots surveyed. The file "Livestock_data_code.zip" contains the data and R code used in the characterization and validation of grazing pressure levels (see Methods). Readme and metadata files including a description of the files, variables and units are provided. All the methodological details can be found in the article. Additional authors from the BIODESERT consortium not included in the author list (we reached the maximum number of authors allowed by figshare) include:  Víctor Rolo, Juan G. Rubalcaba, Jan C. Ruppert, Ayman Salah, Max A. Schuchardt, Sedona Spann, Ilan Stavi, Colton R. A.Stephens, Anthony M. Swemmer, Alberto L. Teixido, Andrew D. Thomas, Heather L. Throop, Katja Tielbörger, Samantha Travers, James Val, Orsolya Valkó, Liesbeth van den Brink, Sergio Velasco Ayuso, Frederike Velbert, Wanyoike Wamiti, Deli Wang, Lixin Wang, Glenda M. Wardle, Laura Yahdjian, Eli Zaady, Yuanming Zhang and Xiaobing Zhou </p

Extreme drought impacts have been underestimated in grasslands and shrublands globally

Climate change is increasing the frequency and severity of short-term (~1 y) drought events—the most common duration of drought—globally. Yet the impact of this intensification of drought on ecosystem functioning remains poorly resolved. This is due in part to the widely disparate approaches ecologists have employed to study drought, variation in the severity and duration of drought studied, and differences among ecosystems in vegetation, edaphic and climatic attributes that can mediate drought impacts. To overcome these problems and better identify the factors that modulate drought responses, we used a coordinated distributed experiment to quantify the impact of short-term drought on grassland and shrubland ecosystems. With a standardized approach, we imposed ~a single year of drought at 100 sites on six continents. Here we show that loss of a foundational ecosystem function—aboveground net primary production (ANPP)—was 60% greater at sites that experienced statistically extreme drought (1-in-100-y event) vs. those sites where drought was nominal (historically more common) in magnitude (35% vs. 21%, respectively). This reduction in a key carbon cycle process with a single year of extreme drought greatly exceeds previously reported losses for grasslands and shrublands. Our global experiment also revealed high variability in drought response but that relative reductions in ANPP were greater in drier ecosystems and those with fewer plant species. Overall, our results demonstrate with unprecedented rigor that the global impacts of projected increases in drought severity have been significantly underestimated and that drier and less diverse sites are likely to be most vulnerable to extreme drought