生物多样性指数在生态评价中的实用性分析——以北部湾为例

为了探讨生物多样性指数(H′)在综合评价近岸海域的实用性,本研究利用水质综合污染指数和浮游植物、浮游动物及底栖生物的多样性指数分别对北部湾近岸海域调查的数据进行污染程度评价,并讨论利用多样性指数评价的合理性。结果表明:用水质综合污染指数评价2014年平水期北部湾近岸海域的水质结果为轻污染;用浮游植物和浮游动物的多样性指数评价结果均为轻中污染;用底栖生物的多样性指数进行污染评价结果则为重中污染。可见,生物多样性指数适用于污染程度较重的水域,而对于像北部湾近岸海域这样较洁净的水域,其与水质评价则存在较大的差异。结合我国近岸海域环境监测的实际情况,当前利用浮游植物来评价最具实用性。生物数据需建立在常年观测的基础上,并与理化监测结果结合起来开展综合性指标评价,才能正确地发挥其作用,从而得到符合实际的结论。

Practicality of Ecological Evaluation by Biodiversity Index: A Case Study of the Beibu Gulf

In order to explore the practicality of the biodiversity index (H'') in the comprehensive evaluation of coastal waters, in this paper the comprehensive pollution index of water quality and the diversity index of phytoplankton, zooplankton and benthic organisms were respectively used to evaluate the pollution degree of the data in the coastal waters of the Beibu Gulf and the rationality of using the diversity index evaluation was discussed. The results showed that using the water quality comprehensive pollution index to evaluate the water quality of the coastal waters of the Beibu Gulf during the flat water period in 2014, the result was light pollution. Using the diversity index of phytoplankton and zooplankton, the results were all light and medium pollution. Contamination evaluation was carried out using the diversity index of benthic organisms, and the result was severe-moderate pollution. It can be seen that the biodiversity index (H'') is suitable for waters with a high degree of pollution, while for cleaner waters such as the near-shore waters of the Beibu Gulf, there is a big difference between the evaluation by biodiversity index and water quality assessment. Combined with the actual situation of environmental monitoring in China''s coastal waters, the current evaluation using phytoplankton is the most practical. Biological data needs to be based on perennial observations and combined with physical and chemical monitoring results to carry out comprehensive indicator evaluation, so they can correctly play their role and the realistic conclusions can be obtained.