Forage provision is more affected by droughts in arid and semi‐arid than in mesic rangelands

作者：Viviana F. Bondaruk, Gastón R. Oñatibia, Roberto J. Fernández, Walter Agüero, Lisandro J. Blanco, Carlos Martín Bruschetti, Alicia Kröpfl, Alejandro Loydi, Jesús Pascual, Pablo L. Peri, Guadalupe Peter, R. Emiliano Quiroga, Laura Yahdjian · 发表于：Journal of Applied Ecology · 年份：2022 · DOI：10.1111/1365-2664.14243 · 被引用次数：28 · 研究领域：Plant Water Relations and Carbon Dynamics、Ecology and Vegetation Dynamics Studies、Rangeland Management and Livestock Ecology

Abstract Droughts are projected to increase in magnitude, frequency and duration in the near future. In rangelands, the provision of valuable ecosystem services such as forage supply for livestock productivity is intimately linked to rainfall patterns, which makes it particularly vulnerable to droughts. Nonetheless, rangelands can differ in their sensitivity to droughts as shown by strong differences in the impacts of inter‐annual precipitation changes on vegetation productivity in different sites. The aim of this study was to assess the sensitivity to droughts of nine rangelands located across a broad aridity gradient in Argentina, South America. We experimentally imposed comparable droughts under field conditions by reducing a fixed proportion of each incoming precipitation event within‐year during three consecutive years and tracked changes in total aboveground and forage productivity. We found that arid and semi‐arid rangelands were more severely impaired in their forage provision by drought than mesic rangelands, that is that sensitivity to drought declined as aridity decreased. Forage productivity decreased on average by c. 50%, in arid and semi‐arid rangelands, whereas mesic sites did not exhibit significant changes between drought and control treatments. The negative impact in forage productivity of arid and semi‐arid rangelands was mainly driven by the productivity reduction of few key plant species at each site. In seven of the nine rangelands, we found detrimental ...