【摘要】 以舟山定海护城河为例,分析浮游植物四季优势种生态位与种间联结性,探讨水生态系统浮游植物群落中优势种间相互作用的生态关系,对环境资源共用的季节性变化,为富营养化污染水体浮游植物群落结构特征研究提供重要依据. 2016年5月至2017年2月4个季节共出现优势种4门12属14种,其中尖肘杆藻、颗粒沟链藻、绿色颤藻、铜绿微囊藻、四尾栅藻和吻状隐藻6种为富营养化指示种.优势种种类具有明显的季节变化,蓝藻细小隐球藻4个季节均为优势种,并在春、秋、冬季为绝对优势种.根据优势度和生态位宽度,14个优势种可以划分为3个类群.生态位重叠值最大值和最小值分别为0.984和0.004,季节性差异较大,冬季≈秋季>夏季>春季.方差比率法求出的各季节优势种VR值均大于1,统计量W检验结果显示,浮游植物优势种间联结性总体上呈显著正相关.基于2×2联列表的χ~2检验,54对优势种对仅有11对有显著联结性,负关联种对多于正关联.总体而言,优势种种间关联程度与生态位重叠程度并不完全一致,可能是浮游植物群落物种多样性高及物种组成季节变化明显所导致.更多还原

【Abstract】 In the present project,niches and species association of seasonal dominant phytoplankton species in Dinghai Moat in Zhoushan City were analyzed,and then interspecific relationship of dominate species and seasonal changes of sharing environmental resources were discussed. A total of 14 dominant species of 12 genera were identified in the Dinghai Moat during four seasons from May 2016 to Feb. 2017,and there were six eutrophication indicator speices,Ulnaria acus,Aulacoseira granulata,Kamptonema chlorinum,Microcystis aeruginosa,Scenedesmus quadricauda and Cryptomonas rostrata. The dominant species changed obviously with the seasons,but Aphanocapsa elachista was dominated absolutely except in summer. According to dominance index and niche width,the 14 dominant species could be divided into three groups. The maximum and minimum niche overlap values were 0.984 and 0.004,respectively,and there was obvious difference among four seasons,winter≈autumn>summer>spring. The VR obtained by the variance ratio method were greater than 1 in each season,and their statistic W values indicated significantly overall positive correlation among dominant species. Based on the 2×2 linkage list and χ~2 test,only 11 pairs among 54 species pairs showed significant association and negatively associated species pairs were more than positively associated ones. As a whole,associated extent between dominant species was not in accordance with overlapped extent of niche,which is possibly resulted from high diversity of species and obvious seasonality of the species composition.更多还原