小黑山岛海域刺参、魁蚶和紫贻贝生境适宜性分析

以小黑山岛临近海域为研究对象,利用生境适宜性指数(habitat suitability index,HSI)模型选划适宜刺参(Stichopus japonicas)、魁蚶(Scapharca broughtonii)和紫贻贝(Mytilus edulis)增殖修复的区域。分别针对每个修复物种筛选出7个生境评价因子,结合专家赋值法和层次分析法确定每个评价因子的权重,利用GIS空间分析模块将现状调查数据进行插值、重分类和栅格计算,绘制研究区域目标种群生境适宜性地图。结果表明:对于刺参和紫贻贝,研究区域均适宜其生长繁殖,同一物种,相同季节在空间上无站位差异,但各季节的生境适宜性分区变化明显;对于魁蚶来说,东北部海域较适宜增殖,其次为西部海域,四季均以较适宜生境为主,仅冬季出现基本适宜生境。水温是造成季节差异的主要因素,底质类型则是引起生境站位差异的重要原因。可为后续的生物多样性保育和生态修复提供基础资料参考。

Habitat suitability of Stichopus japonicas, Scapharca broughtonii and Mytilus edulis in the shallow waters of Xiaoheishan Isalnd

Xiaoheishan Island is located in Bohai Strait and affiliated with Miaodao Archipelago, which lies in Shandong province. The paper identifies the potential area for sustainable restoration of Stichopus japonicas, Scapharca broughtonii and Mytilus edulis in the shallow waters of Xiaoheishan Island using a habitat suitability index model (HSI). Seven screened environmental factors were involved in the HSI model for each species respectively. In summary, the following 9 factors:water temperature, salinity, water depth, pH, sediment composition, dissolved oxygen, organic carbon, current velocity and Chlorophyll a were analyzed in this study. Specific factor piecewise functions have been used to transform environmental factor values into normalized quality indexes (0, 2, 3 and 4). The weight of the each factor was judged with the expert knowledge and the analytic hierarchy process (AHP) method. Thus, the habitat suitable analysis maps were obtained after data interpolate, reclassification and raster calculation with the aid of GIS spatial analysis module. In addition, the analysis of habitat suitability was conducted for four seasons in this paper in order to get more detailed information. First, the results suggest that the entire area was suitable for restoration of S. japonicas and M. edulis, along with no spatial differences but obvious seasonal changes for the 2 species. For S. broughtonii, it is noteworthy that the study area was defined as the suboptimal habitat by the reason of aestivation. Moreover, the northeast region was detected as the optimal site for S. broughtonii propagation, followed by the western part. Meanwhile, the suboptimal habitat accounted for the majority of study area throughout the year with the marginal habitat only appeared in winter. Water temperature was the main factor causing seasonal variation, while sediments composition was remained as the key reason for the differences in habitat sites. Overall, the results indicated the great feasibility for the long-term survival and successful restoration of S. japonicas, S. broughtonii and M. edulis. This study could provide supports and suggestions for subsequent research of biological diversity protection and ecological restoration.