基于Maxent模型的软枣猕猴桃在中国潜在适生区预测

Prediction of potential suitable areas of Actinidia arguta in China based on Maxent model

软枣猕猴桃Actinidia arguta是猕猴桃科Actinidiaceae猕猴桃属Actinidia大型落叶藤本,据《中国植物志》记载,该物种在中国从最北的黑龙江岸至南方广西境内的五岭山地都有分布,但尚未明确其适宜分布区域。因该物种具有独特的食用和药用价值,近年来其种群数量急剧减少,现已被北京市、河北省、吉林省等列为地方性保护物种。本文利用Maxent模型对软枣猕猴桃在中国的潜在适宜分布区进行了预测并对其分布适宜性进行评价。研究结果表明:软枣猕猴桃在我国的适宜分布区总面积约为3.01×10^(6 )km^2;其高适生区主要集中在四川中部、陕西南部、湖北西部和贵州西北部等地中低山区地带,呈圆环状分布。其中软枣猕猴桃在云南、四川、陕西等省份的潜在高适生区域面积最大。利用Jackknife刀切法计算得到影响软枣猕猴桃分布的主要环境因子为最湿季度降水量(500—800 mm)、年均温(12.5—17.5℃)、最冷季度降水量(290—660 mm)和海拔(2000—2690 m),上述环境因子的累计贡献率为79.7%。建议在中高度适宜分布区进行野生软枣猕猴桃的迁地保护和人工种植,并根据其适生环境调整软枣猕猴桃的农业种植繁育规划,为软枣猕猴桃的就地、迁地保护提供了理论依据。

Actinidia arguta is a large deciduous vine of genus Actinidia in Actinidiaceae family.According to Flora Reipublicae Populris Sinicae,this species is distributed from the most northern Amur River bank to the Wuling Mountains in southern Guangxi,but its suitable distribution range has not been defined.Due to its unique edible and medicinal value,the population of Actinidia arguta has decreased dramatically in recent years,therefore it has been listed as a locally protected species in Beijing,Hebei and Jilin provinces.In this study,Maxent model was used to predict the potentially suitable distribution range of Actinidia arguta in China,and the distribution suitability was evaluated.The results showed that the suitable distribution range of Actinidia arguta in China was about 3.01×106 km2.The highly suitable distribution area of Actinidia arguta was mainly concentrated in the middle and low mountain areas of central Sichuan,southern Shaanxi,western Hubei and northwest Guizhou,presenting a circular distribution.Among those areas,Yunnan,Sichuan and Shaanxi provinces covered the largest area.Jackknife knife⁃cutting method was used to calculate the main environmental factors affecting the distribution of Actinidia arguta.The first four main factors,i.e.the wettest season precipitation(500—800 mm),average annual temperature(12.5—17.5℃),the coldest season precipitation(290—660 mm)and altitude(2000—2690 m),provided a significant contribution up to 79%.This paper offered theoretical basis for the in⁃situ and ex⁃situ conservation of Actinidia arguta.It was suggested that the highly and moderately suitable areas could be used for ex⁃situ conservation and cultivation,and the agricultural planting could be improved based on the suitable environment factors.