Annual yields of multispecies grassland mesocosms outperformed monocultures across a drought gradient due to complementarity effects and rapid recovery  

作　　者：Eamon Haughey Jennifer C.McElwain John A.Finn 

机构地区：[1]Department of Natural Resources and the Environment,Atlantic Technological University,Galway,Ireland [2]Botany Department,School of Natural Sciences,Trinity College Dublin,Dublin,Ireland [3]Teagasc,Environment Research Centre,Johnstown Castle,Wexford,Ireland

出　　处：《Grassland Research》2023年第4期309-321,共13页草地研究（英文）

基　　金：FP7 Food,Agriculture and Fisheries,Biotechnology,Grant/Award Number:266018。

摘　　要：Background:More frequent and severe drought events due to climate change pose a major challenge for sustainable forage production in managed grasslands.This study investigated whether multispecies grassland communities can provide greater resistance to and/or recovery from drought compared to monoculture communities.Methods:Mesocosms of Lolium perenne L.,Cichorium intybus L.,Trifolium repens L.and Trifolium pratense L.were established as monocultures,and a four-species mixture.A drought gradient with five levels of water supply ranging from a mild to a severe treatment was applied for 10 weeks,in each of 2 years.Shoot biomass was harvested to assess drought resistance,drought recovery and annual yields.Root mass density and specific root length were measured in Year 2.Results:Across the drought gradient,four-species communities had significantly larger annual yields than each of the four monocultures,indicating transgressive overyielding.This was despite relatively low drought resistance for four-species communities compared with L.perenne and C.intybus monocultures.Recovery of yields following drought was high for all communities.Conclusions:Multispecies swards with complementary traits can provide a viable adaptation option across a wide range of drought severities.Application of a stress gradient methodology allowed a more detailed understanding of stress responses.

关 键 词：climate change DROUGHT forage production functional biodiversity perturbation gradient resilience root traits 

分 类 号：S812[农业科学—草业科学]