Procambarus clarkii was introduced into China as an important aquatic product in early 20th century. It has characteristics of high fertility, rapid growth, adaptability and digging burrows, which could cause damage of crops, cropland and facilities, decrease local biodiversity and thus threaten local ecosystem. Thus, predicting the potential distribution of P. clarkii in response to climate change was essential for preventing and monitoring this species. Based on the distribution of P. clarkii, the maximum entropy (MaxEnt) and genetic algorithm for rule-set production (GARP) models were used to predict its distribution in China under current climate and four climate scenarios (RCP 2.6, RCP 4.5, RCP 6.0, RCP 8.5) in two periods, 2041-2060 and 2061-2080. Then, the modeling results were tested by ROC curves. The results showed that under current climate, the highly suitable region for distribution predicted by the MaxEnt and GARP models were Shanghai, Jiangsu, Zhejiang and Anhui along the Yangtze River. The main environmental variables affecting its distribution were mean temperature of the coldest quarter, minimum temperature of the warmest month, and temperature seasonality, maximum temperature of the warmest month, precipitation of the driest month. Under the future climate scenarios, the suitable area of P. clarkii distribution varied in 2061-2080. The total suitable area of P. clarkii would increase under RCP2.6 and RCP 4.5, whereas under RCP 8.5 the suitable area of P. clarkii would increase, and then decrease. In RCP 6.0, there was no change. The suitable areas of P. clarkii would disperse to different latitude areas and migrate toward high altitude.
克氏原螯虾在20世纪初作为重要的水产品引入中国,但因其繁殖能力强、生长迅速、适应性强、喜掘洞穴,对农作物、池埂及农田水利有一定破坏作用,降低入侵地区当地物种多样性,对当地生态系统造成严重危害。因此,研究未来气候情景下克氏原螯虾适生区的变化,可为其监控和管理措施提供关键信息,有效预防和控制其蔓延。本研究基于克氏原螯虾的分布点,应用最大熵(MaxEnt)模型和规则集遗传算法(GARP)模型模拟了当前气候条件下克氏原螯虾在中国的潜在适生区,并预测了2041—2060年和2061—2080年克氏原螯虾在4种气候变化情景下(RCP 2.6、RCP 4.5、RCP 6.0、RCP 8.5)的分布,采用ROC曲线对预测结果进行检验和评价。结果表明: 在当前气候条件下克氏原螯虾集中分布在上海、江苏、浙江、安徽等长江沿岸地区;最冷季平均温度、最冷月最低温度对克氏原螯虾分布影响最大,其次是温度季节性变化、最暖月最高温度和最干月降水量。在未来气候情景下,2061—2080年克氏原螯虾的适生区面积有不同程度的变化,在RCP 2.6和RCP 4.5情景下总适生面积增加,但在RCP 8.5情景下呈先增后减趋势,而在RCP 6.0情景下无明显变化;克氏原螯虾适生区在空间分布上不仅有纬度方向上的扩散,也有向海拔较高地区迁移的趋势。.
Keywords: Procambarus clarkii; biological invasion; climate change; ecological niche model; potential suitable area.