State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, the Chinese Academy of Sciences, Wuhan, 430072, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China.
State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, the Chinese Academy of Sciences, Wuhan, 430072, PR China.
Sci Total Environ. 2021 May 20;770:145267. doi: 10.1016/j.scitotenv.2021.145267. Epub 2021 Jan 22.
As the main primary producer in stream ecosystems, periphyton is the fundamental of stream ecosystems and plays an essential role in maintaining stream biodiversity. The central Hengduan Mountains is one of the famous global biodiversity hotspots. However, for stream biodiversity conservations, the fundamental information about the spatial pattern of stream periphyton and the determining factors in this region remains largely unknown. To fill this gap, we investigated the spatial pattern of periphyton biomass (measured by chlorophyll a) in four typical streams in the central Hengduan Mountains and analyzed the driving factors, with the perspective of watershed land use and instream water quality. The results of our study found that farmland area, instream dissolved silicate (DSi), and water temperature (WT) had significant negative relationships with the stream periphyton biomass in the central Hengduan Mountains. However, the dissolved inorganic phosphorus (DIP) and dissolved inorganic nitrogen (DIN) had non-significant effects on the periphyton biomass in our study. Further analysis showed that the correlation between the ratio of farmland in the catchment and the DSi is non-significant (r = 0.028, P = 0.698), suggesting that the changes in farmland area will not affect the concentration of dissolved silicate in the stream. This reveals that the stream periphyton biomass was co-determined by the watershed farmland area and instream DSi and WT, but not nitrogen or phosphorus. These results highlight the importance of farmland management and instream DSi for stream ecosystems in the central Hengduan Mountains. Our study investigated the spatial pattern of the stream primary producer in the central Hengduan Mountains region and identified the main determining factors, which could improve our understanding of the high mountain stream ecosystems.
作为溪流生态系统中的主要初级生产者，周丛生物是溪流生态系统的基础，对维持溪流生物多样性起着至关重要的作用。横断山区是全球著名的生物多样性热点地区之一。然而，对于溪流生物多样性保护而言，该地区溪流周丛生物空间格局的基本信息及其决定因素在很大程度上尚不清楚。为了填补这一空白，我们调查了横断山区中部四条典型溪流的周丛生物生物量（以叶绿素 a 表示）的空间格局，并从流域土地利用和溪流水质的角度分析了驱动因素。我们的研究结果表明，农田面积、溪流溶解硅（DSi）和水温（WT）与横断山区中部溪流周丛生物生物量呈显著负相关。然而，溶解无机磷（DIP）和溶解无机氮（DIN）对周丛生物生物量的影响不显著。进一步的分析表明，流域内农田比例与 DSi 的相关性不显著（r = 0.028，P = 0.698），这表明农田面积的变化不会影响溪流中溶解硅的浓度。这表明溪流周丛生物生物量是由流域农田面积和溪流内 DSi 和 WT 共同决定的，而不是氮或磷。这些结果强调了农田管理和溪流内 DSi 对横断山区溪流生态系统的重要性。本研究调查了横断山区中部溪流初级生产者的空间格局，并确定了主要的决定因素，这可以提高我们对高山溪流生态系统的认识。
