气候变化背景下瘤坚大球蚧在中国的适生区预测

Prediction of potential suitable area for Eulecanium gigantea in China under the background of climate change

基于当前178个瘤坚大球蚧分布点和7个主导变量,利用MaxEnt生态位模型预测当前、未来2050年和2070年在RCP45和RCP85情景下瘤坚大球蚧在中国的潜在适生区。分析结果显示,测试集的AUC值为0.982,表明预测结果准确可靠。最干季度平均气温、温度季节性变化方差、最干季度降水量和年平均温度对瘤坚大球蚧的潜在分布影响最大,累计贡献率为90.2%。当前气候条件下,瘤坚大球蚧在中国的潜在适生区范围为23.3°~47.3°N,75.1°~132.6°E,瘤坚大球蚧当前在中国的适生区的总面积为517.9×10^(4)km^(2),占中国国土总面积的53.9%。除海南省、福建省和中国台湾省外,其他省区均有瘤坚大球蚧的潜在适生区。高度适生区主要集中在华北、西北等地区,面积为59.7×10^(4)km^(2),占中国国土总面积的6.2%。未来气候条件下,适生区的北界由吉林西部向北延伸至黑龙江全境,新疆、青海、西藏、内蒙古、黑龙江是新增的瘤坚大球蚧潜在适生区的主要地区;中、高度适生区在北方明显增加,而在南方变化不明显。可见,未来气候条件下瘤坚大球蚧向我国北方扩张风险较大。

Based on the current 178 distribution points and 7 dominant variables,MaxEnt ecological niche model was used to predict the potential suitable areas of Eulecanium gigantea in China at present and under RCP45 and RCP85 scenarios in 2050 and 2070,respectively.The analysis results showed that the AUC value of the test set was 0.982,indicating that prediction results was accurate and reliable.Mean temperature of driest quarter,temperature seasonality,precipitation of driest quarter,and annual mean temperature had the greatest influence on the distribution of E.gigantea,with the cumulative contribution rate of 90.2%.Under the current climate conditions,the range of potential suitable area for this E.gigantea in China was 23.3-47.3°N,75.1-132.6°E,and the total potential suitable area was 517.9×10^(4)km^(2)in China,accounting for 53.9%of China's total land area.Except Hainan Province,Fujian Province and Taiwan Province,other provinces and regions had the potential suitable area of E.gigantea.Highly suitable area was mainly concentrated in North China,Northwest China and other regions,with an area of 59.7×10^(4)km²,accounting for 6.2%of China's total land area.Under the future climate conditions,the northern boundary of the suitable area extends from the western Jilin to the whole of Heilongjiang,and Xinjiang,Qinghai,Tibet,Inner Mongolia and Heilongjiang were the newly added suitable areas of E.gigantea.In our country,the middle and high suitable area increases obviously in the north,but does not change obviously in the south.It can be seen that under the future climate conditions,the risk of expansion of E.gigantea in the north of our country is greater.