Stable isotope ratios of hydrogen separate mammals of aquatic and terrestrial food webs
Stable isotope ratios of hydrogen separate mammals of aquatic and terrestrial food webs
复制标题
氢的稳定同位素比率将水生和陆地食物网中的哺乳动物分开
DOI：
--
复制
发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Stefan Greif
中科院分区：
文献类型：
--
作者：
C. Voigt;D. Lehmann;Stefan Greif
在食物网研究中，氢稳定同位素比（δ2H）越来越多地用作内源标记，以量化有机物质异地输入水生生态系统的相对重要性。然而，目前尚不清楚水生和陆地食物网之间 δ2H 值的差异是否会转化为脊椎动物消费者的 δ2H 值的相应差异。使用三同位素方法，我们询问 12 种同域非迁徙蝙蝠物种的毛皮角蛋白的稳定同位素比率（δ2HK、δ13CK、δ15NK）是否根据它们主要觅食的生态系统（水生或陆地）而有所不同。我们事先对两种圈养物种进行了一项研究，表明 C 和 N 的营养区分存在物种特异性差异，但 H 没有。在野生蝙蝠中，在水生生境中捕捞昆虫的两种鼠耳蝠属物种的稳定同位素比率与采集陆生昆虫的四种同类物种的稳定同位素比率不同，H 大约为 40 ‰，N 大约为 5 ‰，这表明 δ2HK 和 δ15NK 值都可用于识别水生和水生昆虫的成员资格。陆地食物网。此外，我们分别使用拖网蝙蝠和拾穗蝙蝠作为水生和陆地生态系统消费者的代表，评估了空中捕捞蝙蝠物种与陆地食物网的相对关联。我们发现，蝙蝠与陆地食物网的相对关联因物种而异，从 Rhinolophus hipposideros 的约 90% 到 Eptesicus serotinus 的 43% 不等。根据使用 δ2HK 和 δ15NK 值通过标准化椭圆面积估算的同位素生态位尺寸，在 12 个研究物种中差异很大，其中空中鹰猎蝙蝠群成员的同位素生态位重叠最大。我们得出的结论是，δ2HK 和 δ15NK 值是评估哺乳动物与水生和陆地食物网的相对成员资格的合适参数，也可以评估同位素生态位尺寸，从而评估消费者群体中物种的生态位包装。
In food web studies, hydrogen stable isotope ratios (δ2H) are increasingly used as endogenous markers to quantify the relative importance of allochthonous input of organic material into aquatic ecosystems. Yet, it is unclear if differences in δ2H values between aquatic and terrestrial food webs translate into corresponding differences of δ2H values of vertebrate consumers. Using a triple‐isotope approach, we asked if fur keratin of 12 sympatric, non‐migratory bat species differ in stable isotope ratios (δ2HK, δ13CK, δ15NK) according to the ecosystem (aquatic or terrestrial) in which they predominantly forage. We conducted a study with two captive species beforehand that suggested species‐specific differences in trophic discrimination for C and N, but not for H. In wild bats, stable isotope ratios of two Myotis species that trawl insects in aquatic habitats differed from those of four congeneric species that glean terrestrial insects by about 40‰ for H and by about 5‰ for N, indicating that both δ2HK and δ15NK values are useful for identifying membership of aquatic and terrestrial food webs. Further, we assessed the relative association of aerial‐hawking bat species to the terrestrial food web using trawling and gleaning bats as representatives of consumers in aquatic and terrestrial ecosystems, respectively. We found that the relative association of bats to terrestrial food webs varied largely among species, ranging from about 90% in Rhinolophus hipposideros to 43% in Eptesicus serotinus. Isotopic niche dimensions, as estimated by standardized ellipse areas using δ2HK and δ15NK values, varied largely among the 12 study species, with largest overlaps of isotopic niches among members of the aerial‐hawking bat ensemble. We conclude that δ2HK and δ15NK values are suitable parameters for evaluating the relative membership of mammals to aquatic and terrestrial food webs and also to evaluate isotopic niche dimensions and thus niche packing of species within consumer ensembles.