Lessons from the past:isotopes of an endangered rail as indicators of underlying change to tidal marsh habitats
作者机构：u.s.geological survey western ecological research center dixon field officedixoncausa department of animal scienceuniversity of california davisdaviscausa
出 版 物：《Ecosystem Health and Sustainability》 (生态系统健康与可持续性（英文）)
年 卷 期：2017年第3卷第11期
页 面：15-30页
核心收录：
基 金：This work was supported by the U.S.Fish and Wildlife Service
主 题：Historical change estuary food webs isoscapes isotopes Ridgway’s rail tidal marsh
摘 要：Introduction:Tidal marsh systems along the Pacific coast of the United States have experienced substantial stress and loss of area and ecosystem function,which we examined by using the endangered California Ridgway’s Rail,Rallus obsoletus obsoletus(‘rail’)as an indicator of its tidal marsh habitat in the San Francisco *** organized a collection of historical(1885-1940)and modern(2005-2014)rail feathers and analyzed the feather isotope means for delta carbon(δ^(13)C),sulfur(δ^(34)S),and nitrogen(δ^(15)N)by region and time ***:Feather isotopes represented the primary foraging habitat during historical then modern time *** individual nor regional rail feather isotopes suggested freshwater or terrestrial foraging by the *** regions with both historic and modern feather isotopes revealed non-uniform spatial shifts in isotope levels consistent with a marine based food web and significantδ^(15)N ***:Our results supported the rail’s status as a generalist forager and obligate tidal marsh species throughout the historic *** variable isoscape trends generated from feather isotope means illustrated a modern loss of the isotopic homogeneity between regions of historical tidal marsh,which correlated with spatially-explicit habitat alterations such as increasing biological invasions and sewage effluent over ***:These findings have reinforced the importance of tidal marsh conservation in the face of ongoing underlying changes to these important ecosystems.
维普期刊数据库