Testing the generality of sea otter‐mediated trophic cascades in seagrass meadows
Testing the generality of sea otter‐mediated trophic cascades in seagrass meadows
复制标题
测试海草草甸中海獭介导的营养级联的普遍性
DOI：
10.1111/oik.07681
复制
发表时间：
2021
期刊：
影响因子：
3.4
通讯作者：
Eckert, Ginny L.
中科院分区：
文献类型：
--
作者：
Raymond, Wendel W.;Hughes, Brent B.;Stephens, Tiffany A.;Mattson, Catherine R.;Bolwerk, Ashley T.;Eckert, Ginny L.
营养级联的存在和强度可能是当地非生物环境和关键物种相对丰富程度的函数。在阿拉斯加东南部重新引入和扩展海獭Enhya lutris，这是海藻生态系统中已知的关键物种，提供了一个罕见的自然实验，以测试在广泛空间尺度上顶端捕食者-海草营养级联的普遍性。我们在21个地点进行了深入的海草群落调查，调查范围约100公里，有不同的海獭存在，以测试丰度交替的模式和指示营养瀑布的物种之间的直接关系。我们的分析揭示了顶端捕食者-海草营养级联理论预测的一些营养关系，包括海獭和螃蟹之间的强烈负关系，以及硝酸盐、海草、附生植物和附生动物之间的许多预期关系。然而，营养级联中的其他预期关系没有得到支持--包括螃蟹和表栖动物之间没有关系，这是营养级联中的关键环节。由于缺乏所有假设的直接关系的证据，我们得出结论，阿拉斯加东南部可能不存在海獭介导的营养级联，这可能是由于局部尺度因素，包括阿拉斯加东南部海草群落的空间异质性、低资源可获得性和非线性食物链。然而，相关分析表明，阿拉斯加东南部海草群落的生物和环境变量之间存在进一步的相互作用，包括海獭和海草生物量之间的正相关。这些结果表明，恢复顶端捕食者种群的影响可能不能在区域和空间尺度上推广，突出了对这些种群的生态和管理进行局部评估的必要性。
The presence and strength of trophic cascades can be a function of the local abiotic environment and relative abundance of key species. The reintroduction and expansion of sea ottersEnhydra lutris, a known keystone species in kelp ecosystems, in southeast Alaska provides a rare natural experiment to test the generality of a apex‐predator – seagrass trophic cascades across a broad spatial scale. We conducted an in‐depth seagrass community survey at 21 sites spanning ~100 km with variable sea otter presence to test for patterns of alternating abundance and direct relationships between species indicative of trophic cascades. Our analysis revealed some of the trophic relationships predicted by the apex predator–seagrass trophic cascades theory, including a strong negative relationship between sea otters and crabs and many of the expected relationships between nitrate, seagrass, epiphytes and epifauna. Other expected relationships within a trophic cascade, however, were not supported – including no relationship between crabs and epifauna, a critical link in the trophic cascade. Given the lack of evidence for all hypothesized direct relationships, we conclude that a sea otter mediated trophic cascade may not be present in southeast Alaska and could be due to local scale factors including the spatial heterogeneity, low resource availability and non‐linear food chains in southeast Alaska seagrass communities. However, correlation analyses suggest further interactions among biological and environmental variables in southeast Alaska seagrass communities, including a positive correlation between sea otters and seagrass biomass. These results suggest that the effects of recovering apex‐predator populations may not be generalizable across regions and spatial scales, highlighting a need for local assessment on the ecology and management of these populations.
登录
查看更多内容
过去栖息地的物种恢复和重新殖民：河口海獭的科学和保护教训
影响因子：
2.7
作者：
Brent B. Hughes;K. Wasson;M. Tinker;Susan L. Williams;Lilian P. Carswell;K. Boyer;M. Beck;R. Eby;R. Scoles;M. Staedler;Sarah Espinosa;M. Hessing‐Lewis;Erin U Foster;Kathryn M. Beheshti;Tracy M Grimes;B. H. Becker;L. Needles;Joseph A. Tomoleoni;Jane Rudebusch;Ellen M. Hines;B. Silliman
通讯作者：
B. Silliman
大叶藻滨海草甸沙质和泥质根际沉积物中磷循环的生物地球化学意义（丹麦）
影响因子：
2.5
作者：
M. Holmer;C. Carta;F. Andersen
通讯作者：
F. Andersen
大自然过去的幽灵如今是否仍困扰着生态？
影响因子：
9.2
作者：
B. Silliman;Brent B. Hughes;Leo Chan Gaskins;Qiang He;R. Stepp
通讯作者：
R. Stepp
影响因子：
3.7
作者：
Ripple, WJ;Beschta, RL
通讯作者：
Beschta, RL
影响因子：
2.5
作者：
Baden, Susanne;Emanuelsson, Andreas;Aberg, Per
通讯作者：
Aberg, Per