Stable isotopes reveal food web reliance on different carbon sources in a subtropical watershed in South China.
Stable isotopes reveal food web reliance on different carbon sources in a subtropical watershed in South China.
复制标题
稳定同位素揭示了华南亚热带流域食物网对不同碳源的依赖。
DOI：
10.1016/j.limno.2017.11.003
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发表时间：
2018
期刊：
影响因子：
1.7
通讯作者：
Haiyan Li
中科院分区：
文献类型：
--
作者：
Yanyi Zeng;Zini Lai;Wanling Yang;Haiyan Li
珠江流域是我国南方最大的亚热带流域，近几十年来，该流域的鱼类数量急剧下降。为了保护河流栖息地和维持河流生态系统的完整性，我们需要了解不同的碳源如何对水生食物网做出贡献。我们使用稳定的碳和氮同位素的信息和IsoSource软件来研究不同碳源对PRW食物网的相对贡献。我们发现，C3植物（C3 P），颗粒有机物（POM），沉水水草（SWG），和C4植物（C4 P）的稳定签名显着不同，分为四个不同的群体。其中，C3 P对某些消费者来说是一种高而稳定的碳源，而C4 P是一种低但稳定的碳源。相比之下，POM和SWG组的贡献不稳定，并且在第1和第99个置信区间之间变化很大。结果表明，C3 P，POM和SWG组可能是重要的碳源PRW食物网。对提供超过50%的各组的第99个置信区间贡献的分析表明，PRW食物网中的消费者可分为主要依赖C3 P的消费者、主要依赖SWG的消费者、潜在依赖C3 P-SWG的消费者和潜在依赖POM-SWG的消费者。这项研究提供了基本的信息，将有助于支持保护和管理的PRW生态系统，并将特别有用，以帮助恢复沉水植物床和河岸缓冲带在这个流域。
Fish species in the Pearl River Watershed (PRW), the largest subtropical watershed in southern China, have declined dramatically in recent decades. To protect river habitats and maintain the integrity of river ecosystems, we need to know how different carbon sources contribute to aquatic food webs. We used information about stable carbon and nitrogen isotopes and IsoSource software to investigate the relative contributions of different carbon sources to the food web of the PRW. We found that the stable signatures of C3plants (C3P), particulate organic matter (POM), submersed water grasses (SWG), and C4plants (C4P) were significantly different and fell into four distinct groups. Of these, C3P was a high and stable source of carbon to certain consumers, while C4P was a low but stable carbon source. In comparison, the contributions from the POM and SWG groups were unstable and varied widely, between the 1st and 99th confidence intervals. The results suggest that the C3P, POM, and SWG groups might be important carbon sources for the PRW food web. Analysis of the 99th confidence interval contribution of each group that provided more than 50% showed that consumers in the PRW food web might be divided into those that mainly relied on C3P, those that mainly relied on SWG, those that potentially relied on C3P-SWG, and those that potentially relied on POM-SWG. This study provides basic information that will help support the protection and management of the PRW ecosystem, and will be especially useful to help restore submersed macrophyte beds and riparian buffer strips in this watershed.