踩踏对砂质滩小型底栖动物的影响——现场扰动实验初步结果

Trampling Effects on Sandy Beach Meiofauna:Preliminary Results of Field Experiments

在青岛太平湾砂质滩进行人为踩踏扰动现场实验,初步了解踩踏对砂质滩小型底栖动物的影响。现场扰动实验结果显示,受踩踏影响小型底栖动物垂直分布在12 h内发生了显著的变化。小型底栖动物对人为踩踏扰动的响应模式为向深处迁移致使丰度降低,并非平行向周围迁移。同时,本研究比较分析了旅游旺季(7月)和淡季(10月)小型底栖动物的丰度和分布,结果显示,旅游旺季小型底栖动物丰度及其优势类群海洋线虫丰度明显低于淡季,并在中潮带表现突出。季节影响之外,旅游活动,包括沙滩上的散步、奔跑、嬉戏及浅海区的游泳活动引起的沉积物改变可能是导致小型底栖动物的丰度、组成及分布变化的重要原因之一。有关小型底栖动物群落对旅游扰动的响应机理还需要在更广的范围开展更深入的研究。

We carried out field experiments of trampling effects on meiofauna in sandy beach of Taiping Bay, Qingdao in June, 2008. Trampling was undertaken in a manner to simulate the tourism activities. Meiofauna was collected 0 h, 12 h, 24 h, and 144 h after trampling treatment. The results showed that meiofauna vertical distribution changed significantly in 12 hours. Results suggest that the predominant effect of trampling disturbance may cause meiofauna to bury deeper into the sediment. At the same time, comparative studies of meiofauna abundance and distribution were conducted on the studied sandy beach separately in tourism season （July） and off-season （October）. It aimed to understand the effects of tourism activities on meiofauna abundance and distribution. In tourism season meiofauna abundance, free- living marine nematode in particular, was significantly lower than that in off-season. And this was outstanding in the middle intertidal zone. Besides seasonal effect, tourism activities, including walking, running, playing on the beach and swimming in the surf zone, had a marked effect on the sediment structure. Tourism induced sedimentary variations may have contributed to the main reasons for changes in meiofaunal abundance, composition and distribution. Meiofaunal responses to tourism activities need to be studied in a broader and deeper extent.