水体富营养化及物种入侵对星云湖食物网的影响  

The effects of water eutrophication and species invasion on the food web of Xingyun Lake

作　　者：邓素炎 郭雯 温雯雯[1] 王明果 黄林培[1] 陈子栋 陈光杰[1] 赵帅营 DENG Su-yan;GUO Wen;WEN Wen-wen;WANG Ming-guo;HUANG Lin-pei;CHEN Zi-dong;CHEN Guang-jie;ZHAO Shuai-ying(Yunnan Key Laboratory of Plateau Geographic Processes and Environmental Change,Faculty of Geography,Yunnan Normal University,Kunming 650500,China;Meteorological Bureau of Fengning Manchu Autonomous County,Chengde 068350,China;Yunnan Geological Mine Mapping Academy Co.,Ltd,Kunming 650217,China)

机构地区：[1]云南师范大学地理学部,云南省高原地理过程与环境变化重点实验室,云南昆明650500 [2]河北省丰宁满族自治县气象局,河北承德068350 [3]云南省地矿测绘院有限公司,云南昆明650217

出　　处：《中国环境科学》2024年第2期932-943,共12页China Environmental Science

基　　金：国家自然科学基金资助项目(42067064,42171072);云南省重点研发计划项目(202203AC100002-02);云南省野外科学观测研究站基金资助项目(202305AM070002);云南省院士专家工作站基金资助项目(2017IC063)。

摘　　要：以云南浅水富营养化湖泊星云湖为研究区域,于2019~2020年对星云湖水质样品、初级生产者浮游植物(浮游碳源)、沉水植物(底栖碳源)、流域有机质(陆源)以及消费者浮游动物、底栖动物、鱼类等生物样品进行系统采集,甄别了星云湖初级生产者和消费者的碳、氮稳定同位素组成特征,并使用MixSIAR模型对消费者食物来源进行量化,对比分析以初级生产者(模式A)、以碳源贡献权重(模式B)和以初级消费者(模式C)3种不同氮稳定同位素基准计算的消费者营养级结果,进而构建适用于浅水富营养化湖泊的食物网结构,探讨富营养化以及外来入侵物种可能对星云湖食物网产生的影响.结果表明,MixSIAR模型结果显示浮游碳源、底栖碳源、陆源对消费者的贡献分别为77.3%、12.2%、10.5%,且沿岸带、敞水区不同生境鱼类的碳同位素信号不存在显著性差异,与浮游碳源的相近,指示浮游碳源是富营养湖泊消费者最主要的食物来源,其能量传输以浮游路径为主.对于不同食性的鱼类,杂食性鱼类的基础食物源(CR)跨度大,而肉食性鱼类营养长度(NR)更高,两者的核心生态位分离,且杂食性鱼类的核心生态位面积(3.79)高于肉食性鱼类(2.46),表明杂食性鱼类具有更高的适应性.模式B计算的营养级结果与消费者的食性较一致,可应用于星云湖消费者营养级计算.模式B结果显示,星云湖食物链长度为3.73,顶级掠食者为抚仙鲇,入侵物种太湖新银鱼营养级(3.37)次之,且与星云白鱼(3.01)在食物和生存空间上存在竞争.研究认为,富营养化导致的物源和能流的改变以及外来物种的入侵是造成星云湖土著鱼类资源衰退、食物网结构中生物多样性减少及生态系统功能弱化的主要原因.Samples of lake water quality,primary producer phytoplankton(pelagic carbon source),submerged plants(benthic carbon source),terrestrial organic matter(terrestrial sources),and consumer zooplankton,benthos and fishes were systematically collected from Xingyun Lake,a shallow and eutrophic lake of Yunnan,in 2019~2020.These samples were analyzed to identify the characteristics of carbon and nitrogen stable isotope composition of primary producers and consumers,and to quantify the food sources of consumers using the MixSIAR model.We tried to find out the best model for constructing the food web structure applicable to this shallow and eutrophic lake by a comparison of the outputs from three calculation models,with the isotopic baseline of primary producer(Model A),carbon source contribution weight(Model B),and primary consumer(Model C),and thus revealed the possible effects of eutrophication and invasive alien species on the lake food web.The contributions of planktonic,benthic and terrestrial carbon source to consumers were 77.3%,12.2%and 10.5%,respectively.Moreover,no significant difference in the carbon isotope signals of fishes between littoral zone and pelagic zone indicated that planktonic carbon source was the most important food source of consumers in eutrophic lakes,and its energy flow of food webs was dominated by planktonic pathway.For fishes of different diets,omnivorous fish had wide dietary sources and carnivorous fish had a higher trophic level,separating their core ecological niches.The core ecological niche of omnivorous fish(3.79)was higher than that of carnivorous fish(2.46),indicating that omnivorous fish had higher adaptability.The trophic level results calculated by model B were more consistent with the food habits of consumers than other two models,and the model B could be selected as the best model applied to the calculation of trophic level of consumers in Xingyun Lake.The results of Model B showed that the food chain length of Xingyun Lake was 3.73,and its top predator was Silurus graham,foll

关 键 词：富营养化 物种入侵 碳氮稳定同位素 MixSIAR模型 营养级 湖泊食物网 星云湖 

分 类 号：X524[环境科学与工程—环境工程]