黑龙江中游浮游植物多样性动态变化及水质评价

运用灰关联分析、单因子评价与生物多样性指数相结合的方法,于2010年5月、7月、9月通过对黑龙江浮游植物的多样性及其季节变动的研究,评价黑龙江中游(黑河?抚远江段)水质现状。结果表明:黑龙江中游浮游植物共计8门115种属,种类组成以硅藻为主。浮游植物的多样性丰富(H’、J三季均值分别在3.66～3.86、0.83～0.88之间);多样性指数的最大值和最小值分别出现在绥滨、黑河、三江口江段;黑龙江中游浮游植物的多样性表现出明显的季节变化规律,夏季较春、秋季丰富。应用灰关联分析评价黑龙江中游水质类别,呈现黑河、逊克、嘉荫、萝北、绥滨、三江口、抚远采样点水质与《地表水环境质量标准》(GB3838-2002)中的Ⅰ类水质的关联度最大,分别为0.788、0.903、0.851、0.856、0.864、0.791和0.879。结合生物多样性指数及灰关联分析、单因子评价法综合分析,黑龙江中游(黑河-抚远江段)水质现状良好,属于寡污-清洁型河流,水质类别为Ⅰ-Ⅱ类,能够满足珍稀水生生物栖息地、鱼虾类产卵场、仔稚幼鱼索饵场的水质要求。同时,黑龙江中游江段浮游植物多样性丰富,水质现状良好,也为恢复渔业资源,保护水生生物提供了条件。本研究旨在为黑龙江中游生态环境评价以及合理制定资源恢复策略提供科学依据。

Dynamics of phytoplankton diversity and water quality evaluation in the middle reaches of Heilongjiang River

The characteristics of phytoplankton were investigated in the middle reaches of Heilongjiang River in May(spring),July(summer) and September(autumn) of 2010.The dynamics of phytoplankton diversity were examined and water quality analyzed using three phytoplankton diversity indices,by gray relational analysis,and by single-factor water quality assessment methods.The species composition of Bacillariophyta was highest in the middle reaches of the river.Phytoplankton were abundant and with high diversity(the value of H’ was 3.66–3.86;the value of J was 0.83–0.88).The lowest values of three diversity indices were measured at two sampling sites(HM-1 and HM-6) in the spring.The diversity of phytoplankton revealed seasonal dynamics,being higher in summer than in spring and autumn.Gray relational analysis indicated that the relational degree was closest to level I of the graded environmental quality standards for surface waters.The calculated values of relational degree were 0.788,0.903,0.851,0.856,0.864,0.791 and 0.879 at sites HM-1,HM-2,HM-3,HM-4,HM-5,HM-6 and HM-7,respectively.Combining the gray relational analysis with single-factor water quality assessment methods,and di-versity indices,indicated that the water quality was within the OS standard ’clean’ in the middle reaches of Heilongjiang River,and that the water quality was level I–II.This quality provides a suitable habitat for rare aquatic species,for spawning of fish and shrimps,or as a feeding ground for larvae.The river could also provide conditions for the restoration of fishery resources and for protection of aquatic resources.