漂浮植物水鳖对沉水植物黑藻生长及它们对水质的影响作用  

Influence of the Floating Macrophyte Hydrocharis Dubia on the Growth of the Submerged Macrophyte Hydrilla Verticillata and Their Effects on Water Quality

作　　者：李敦海[1] 史龙新 李根保[1] 王高鸿[1] 陈武雄[1] 刘永定[1] 

机构地区：[1]中国科学院水生生物研究所,湖北武汉430072 [2]无锡市太湖湖泊治理有限责任公司,江苏无锡214023

出　　处：《环境科学与管理》2007年第12期54-58,共5页Environmental Science and Management

摘　　要：通过黑藻和不同覆盖度水鳖的组合,研究了漂浮植物对沉水植物的影响。结果发现,在初始时水鳖覆盖度大于30%,则黑藻的生长受到抑制,且总生物量降低。与无水鳖覆盖的对照相比,覆盖度为30%的实验组黑藻的生长反而受到促进,表现在总生物量增加和植株数量增加上,另外,由于漂浮植物的遮光作用,使水下光强降低和沉水植物黑藻的植株延长。在对水质指标的影响上,由于漂浮植物和沉水植物的此消彼长,对总氮和总磷的影响比较一致,均使其降低。对照组的CODMn在初期由于黑藻植株的腐烂而上升,后来与其它实验组一样均降低。由于漂浮植物的大量存在,水体的溶解氧则大大降低。因此,水鳖从溶解氧、光照条件、营养条件、pH等方面都给水体带来影响,最终影响到沉水植物的生长。这些结果为我们在水体生态重建实践中对漂浮植物和浮叶植物的管理提供借鉴。The influence of the free floating macrophyte Hydrocharis dubia on the growth of the submerged macrophyte Hydrilla verticillata was studied by using different coverage of H. dubia. Results showed when the initial coverage of H. dubia was higher than 30% , the growth of H. verticillata would be inhibited and its total biomass decreased. The growth of H. verticillata in the group of 30% coverage of H. dubia was promoted both in total biomass and number of plants, when compared with control. For the shading effect of floating macrophyte, the light intensity under water was decreased hence the length of H. verticillata plant was increased. In all groups, the total nitrogen （TN）and total phosphorus （TP）concentrations in water all decreased with the growth of these two types of macrophytes. At initial, the CODMn concentration in control group increased because of the decay of H. verticillata plants, then decreased to the same level as other groups. For the mass growth of floating macrophyte H. dubia, the dissolved oxygen （DO）concentration decreased notably. Thus 14. dubia affected the water quality through changing DO, light conditions, nutrient status and pH, and finally influenced the growth of submerged macrophytes. We can take benefits from these results to manage the floating macrophytes and the floating leaved macrophytes when in the practice of aquatic ecosystem reconstruction.

关 键 词：漂浮植物 沉水植物 水鳖 黑藻 生长 水质 

分 类 号：X171.1[环境科学与工程—环境科学]