互花米草盐沼湿地大型底栖动物时空分布特征

The temporal and spatial distributions of the macrobenthos in Spartina alterniflora salt marsh

互花米草是从美国引进中国的外来物种,在江苏沿海栽种30多年,已经成为潮滩的优势种。以互花米草长势较好的东台笆斗垦区外互花米草盐沼湿地作为研究区,通过一条断面上4个样点的4个季节垂直分层的大型底栖动物采样,通过筛洗、固定、鉴定、统计以及动物群落指标计算等过程,得出互花米草盐沼湿地大型底栖动物的物种主要由4门5纲12科15种组成,其中以纵带锥螺和微黄镰玉螺为优势种,分布占34.91%和32.23%;在季节变化上,互花米草盐沼湿地大型底栖动物物种个体数有较大季节差异,秋季最高,夏季最低;在空间分布上,互花米草盐沼湿地大型底栖动物平均个体数H2点最多,H4点最少,纵带锥螺、双齿围沙蚕等大部分物种在各点均有分布,具有较广的生境范围;在垂直分层上,各季节各采样点都是上层分布最多。

Spartina alterniflora Loisel was introduced from USA to China and it is a new adventitious species of plant to Chinese environment. This plant that covers a vast area between mean sea level and mean high level has become a dominant plant on tidal fiats. Four sampling sites were selected outside the Badou reclamation area where the Spartina alterniflora Loisel grew well, and the macrobenthos sampling was collected at different depths in four seasons, and then the temporal and spatial distributions of the macrobenthos in Spartina alterniflora salt marsh were analyzed by using the methods of sieving, fixation, identification and calculation of the community indicators. The result shows that there are 4 phylums, 5 classes, 12 families and 15 species of macrobenthos in Spartina alterniflora loisel salt marshes, and the Batillaria zonalis Bruguiere and Zunatis gilva Philippi are the dominant animals, accounting for 34.91% and 32.23% respectively. The macrobentho animal species have a greater seasonal difference in the number of individuals, the highest in summer and lowest in autumn. The community indicators have no significant variation with the change of seasons. In terms of spatial distribution, the largest average number of macrobenthos individuals is observed at points H2 where the Spartirta alterniflora loisel grows well, and the smallest is found at point H4 with no gross covered, and some macrobenthos, such as BatiUaria zonalis Bruguiere and Perinereis aibuhitensis Grube are observed at all the points, showing that this plant has a wide habitat. As for vertical distribution, the upper layers have the largest amount of macrobenthos in all the seasons and at all the sampling sites.