Alpine tundra ecosystems are highly sensitive to climate change,particularly due to their dependence on the duration and timing of snow cover.This study investigated the effects of the climate extreme years 2022 and 2...Alpine tundra ecosystems are highly sensitive to climate change,particularly due to their dependence on the duration and timing of snow cover.This study investigated the effects of the climate extreme years 2022 and 2023 on carbon(C)and nitrogen(N)forms in two alpine tundra communities:snowbed(SB)and Carex curvula(CC),located at high elevation in the North-West(NW)Italian Alps.During these years,both sites experienced exceptionally low snow cover duration and elevated mean soil temperature during the snow-free season.Dissolved organic carbon(DOC)concentrations significantly increased by+65%in SB and+42%in CC compared to 2016-2021,likely reflecting enhanced microbial decomposition of organic matter.In contrast,soil ammonium and nitrate levels showed no significant changes,indicating differential responses between C and N processes.These findings suggest that DOC is a sensitive(early)indicator of climate-induced shifts in soil functioning.Given the critical role of alpine tundra in global C cycling,understanding DOC dynamics under climate extreme events is crucial to predict future ecosystem feedback to global change.展开更多
基金supported by the National Recovery and Resilience Plan(NRRP),Mission 4 Component 2 Investment 1.4-Call for tender No.3138 of 16 December 2021,rectified by Decree n.3175 of 18 December 2021 of Italian Ministry of University and Research funded by the European Union–Next Generation EUProject code CN_00000033,Concession Decree No.1034 of 17 June 2022 adopted by the Italian Ministry of University and Research,CUP D13C22001350001,Project title“National Biodiversity Future Center NBFC”supported by the project NODES,which has received funding from the MUR-M4C21.5 of PNRR funded by the European Union-Next Generation EU(ECS00000036-CUP[D17G22000150001])。
文摘Alpine tundra ecosystems are highly sensitive to climate change,particularly due to their dependence on the duration and timing of snow cover.This study investigated the effects of the climate extreme years 2022 and 2023 on carbon(C)and nitrogen(N)forms in two alpine tundra communities:snowbed(SB)and Carex curvula(CC),located at high elevation in the North-West(NW)Italian Alps.During these years,both sites experienced exceptionally low snow cover duration and elevated mean soil temperature during the snow-free season.Dissolved organic carbon(DOC)concentrations significantly increased by+65%in SB and+42%in CC compared to 2016-2021,likely reflecting enhanced microbial decomposition of organic matter.In contrast,soil ammonium and nitrate levels showed no significant changes,indicating differential responses between C and N processes.These findings suggest that DOC is a sensitive(early)indicator of climate-induced shifts in soil functioning.Given the critical role of alpine tundra in global C cycling,understanding DOC dynamics under climate extreme events is crucial to predict future ecosystem feedback to global change.
