基于MAXENT模型评估北部湾潮间带中国鲎和圆尾鲎稚鲎的潜在地理分布及种群保育对策

鲎具有极高的经济价值和科研意义。近年来由于过度捕捞和栖息地受损等原因,亚洲鲎种群数量正急剧下降。鲎漫长的生命周期使得鲎资源的保护和增殖迫在眉睫。生态位模型已经广泛应用于物种的潜在地理分布预测。基于实地调研数据和公开发表的北部湾中国海域中国鲎和圆尾鲎地理分布数据,运用MAXENT模型得到中国鲎和圆尾鲎在广西北部湾(中国部分)的栖息地适宜度指数(Habitat suitability index, HSI),确定了这两种稚鲎在北部湾中国海域潜在适生区。模型分析结果表明,潮间带坡度和地形指数是影响中国鲎分布的主要环境因子,而潮间带底质的有机物含量和植被指数是影响圆尾鲎分布的主要环境因子,根据研究结果建议在两种稚鲎适生区建立保护区,进行人工放流稚鲎,加强对海草和红树林的生态建设,进而促进鲎资源种群恢复和发展。

Prediction of potential distribution areas of Chinese horseshoe crab and mangrove horseshoe crab in the Beibu Gulf of Guangxi based on MAXENT model and their population conservation strategies

Horseshoe crab has high economic and scientific values. In recent years, because of overfishing and habitat degradation, the population of horseshoe crabs in China is decreasing rapidly. However, their long life cycle makes it extremely urgent to protect horseshoe crabs. Ecological niche models have been widely applied to predict the potential geographic distribution of species. The habitat suitability index of the Chinese horseshoe crab Tachypleus tridentatus and mangrove horseshoe crab Carcinoscorpius rotundicauda in the Beibu Gulf (Chinese part) was determined by using the maximum entropy model and the distribution of habitat suitability of the two types of juvenile horseshoe crab in the Beibu Gulf was determined based on field survey data and published data on the geographical distribution of two horseshoe crab species in the Beibu Gulf. The model analysis results showed that the slope of the intertidal zone and topographic index were the main environmental factors affecting the distribution of the Chinese horseshoe crab, while the organic content and vegetation index of intertidal sediment were the main environmental factors affecting the distribution of the mangrove horseshoe crab. According to the results, to promote the recovery and development of horseshoe crab resources, protected areas should be established, artificial release of juvenile horseshoe crabs in habitat suitability areas of horseshoe crab should be conducted, and the ecological construction of seagrasses and mangroves in these areas should be strengthened.