摘要
根据1998～1999年春、夏、秋、冬4个航次粤西海域饵料生物的调查资料,在GIS的支持下利用数据插值、栅格图形加权平均和数学运算模型等空间分析手段对该海域饵料生物栖息密度的时空分布特征及其生物多样性进行了综合的分析和评价。结果表明,调查期间粤西海域饵料生物的综合水平均呈现出近岸水域高、离岸水域低的分布趋势,即从北向南呈递减趋势。整个海域以冬季的饵料生物水平最高,其密集分布区范围最广,达5级水平;春季和秋季密集区的分布范围较为相似;而夏季饵料生物的密集区范围较小,仅为3级水平。在季节变化趋势上,浮游动物和底栖生物数量为冬季大于夏季大于秋季大于春季,浮游植物数量为冬季大于秋季大于夏季大于春季,总体以冬季水平最高,春季水平最低。调查期间粤西海域各个季节之间饵料生物多样性指数和均匀度相差不大,其平均值变化范围分别为3.02～3.43和0.60～0.72,显示出稳定的多样性水平。多样性阈值的分布较为均匀,绝大部分水域为2～3级水平,个别水域达4级水平,其密集区基本分布于整个海域的中部或南部,总体上以离岸水域的多样性阈值高于近岸水域,但各个季节的平面分布趋势略有差异,表现为密集区出现的范围和水域稍有不同。
Since 1950, a series of surveys on the fishery ecological environment in the northern South China Sea have been carried out, but the data for food organisms (including phytoplankton, zooplankton and benthos) in the area (especially in the west Guangdong Sea Area) were seldom reported. In order to understand the variation regulation of the food organism biomass and species population in the West Guangdong Sea Area, the spatio-temporal distribution of the inhabit density and the biodiversity of the food organisms in the waters were analyzed and evaluated synthetically by using the spatial analytical methods of data interpolation, grid average weight and mathematic calculation model supported by Geographical Information System (GIS). The basic data were from the four cruises of surveys on the food organisms in the area in the 4 seasons from 1998 to 1999. During the survey, the synthetic level of the food organisms in the West Guangdong Sea Area showed a trend of high in the coastal waters and low in the offshore waters, and from north to south the food organism level declined gradually. In winter the food organism level was the highest, and the dense area was the widest with the highest level occurring in the coastal waters from Leizhou Bay to Shuidong Port which reached grade 5. In spring and autumn the food organism levels were lower than those in spring, and the distribution of the dense areas were similar which occurred in the coastal waters around Shuidong Port. While in summer the food organism level was the lowest, and the relative dense area was small with the level only reached grade 3. The seasonal variation of the food organism level of zooplankton and benthos followed the trend of winter>summer>autumn>spring, and for phytoplankton it was winter>autumn>summer>spring. In the analysis, 267 species of phytoplankton, 281 species of zooplankton and 175 species of benthos were identified, respectively. The seasonal succession of the dominant species of the food organisms was obvious. For phytoplankton, Skeletonema costatum was the dominant species in spring and summer; Thalassiothrix frauenfeldii, Navicula subminuscula and Thalassionema nitzschioides constitute the dominant species in summer and autumn, while Thalassiosira subtilis was the dominant species in autumn and winter. For zooplankton, Sagitta enflata and Copepoda larva were the perennial dominant species. For benthos, Callianassa japonica was the dominant species in spring, summer and autumn, and Notomastus sp. was the dominant species in summer and winter, while Aricidea fragilis was the dominant species in autumn and winter. During the survey the differences of the food organism biodiversity and evenness among the four seasons were unobvious in the West Guangdong Sea Area. The annual average variation of the diversity and evenness was (3.03-3.43) and 0.60-0.72, respectively, which showed a stable biodiversity level. The diversity threshold distributed evenly with most of the waters being the level of grade 2 to grade 3, and some specific area even reached grade 4. The dense area of the threshold occurred basically in the middle or the southern waters, which showed totally the trend that the offshore waters was higher than the coastal waters in diversity threshold. The little difference for the spatial distribution of the dense area of the threshold among the four seasons was that the occurring scope and place differed slightly.
出处
《中国水产科学》
CAS
CSCD
北大核心
2004年第5期440-447,共8页
Journal of Fishery Sciences of China
基金
国家海洋勘测专项(HY126-02-03)
广东省重大科技兴海项目(A200099E01).
关键词
GIS
粤西海域
饵料生物
多样性阈值
GIS
West Guangdong Sea Area
food organism
diversity threshold
