我国见血封喉适生区的气候特征分析

见血封喉具有重要的药用价值和使用价值,是我国热带季节性雨林的主要树种之一。了解见血封喉的适生区的气候因子情况,有利于其资源的保护和开发利用。本研究基于生态位模型理论对我国见血封喉地理分布区气候因子进行分析。以见血封喉在国内的现有天然地理分布数据为基础,通过DIVA-GIS获得见血封喉地理分布区气候因子;以分布样地内的海拔和气候数据20个指标进行主成分分析,结果获得4个主成分,其方差总贡献率为93.7%,其中第1主成分为海拔、降雨量和温度的综合因子;第2主成分为主要与低温有关的因子;第3主成分为主要与降雨量相关的因子;第4主成分为主要与极端温度相关的因子,其方差贡献率分别为42.9%、31.3%、13.0%和6.5%。以最大熵模型理论对见血封喉建立在我国适生区预测模型,预测的模型经ROC验证,模型的训练AUC为0.990,数据检验显示所建立的模型优良,预测精度高;刀切法检验结果表明,年平均气温bio1为影响见血封喉地理分布区气候影响分布的最关键生物气候因子,其次为平均日较差bio2。见血封喉在我国的适生区为广东、广西、海南、云南、台湾。最适生区面积最大的是广东,其次为广西,第三是海南;而高适生区和一般适合区主要是广西;云南和台湾为低适区。

Climatic Characteristics Analysis of Antiaris toxicaria Lesch.in the Suitable Area in China

Antiaris toxicaria Lesch.is one of the dominant tree species of tropical seasonal rain forest in China,it has important medicinal and use values.To understand the climate factors in the suitable area of A.toxicaria is conducive to its protection,development and utilization of resources.Based on the niche model theory,in this study the climatic characteristics and suitable distribution area of A.toxicaria were studied.Based on the existing natural geographical distribution data of A.toxicaria in China,the climatic data in the geographical distribution area of A.toxicaria were obtained from Worldclim data by DIVA-GIS.Principal component analysis(PCA)was carried out with 20 altitude and climate indicators.The results of the principal component analysis showed that there were four principal components obtained,the total contribution rate of variance was 93.7%.The first principal component was a comprehensive factor of altitude,rainfall and temperature,the second was related to low temperature,the third was mainly related to rainfall,the fourth was related primarily to extreme temperature,and its variance contribution rate was 42.9%,31.3%,13.0%and 6.5%,respectively.Based on the maximum entropy model theory,the prediction model of the A.toxicaria suitable area in China was established.The prediction model was validated by ROC,and the AUC of the training data was 0.990,and these results showed that the model was excellent with high prediction accuracy.The results of Jackknife test indicated that annual mean temperature(bio1)was the most key factor of biological climate which affecting the geographical distribution area of A.toxicaria,followed by mean diurnal range(bio2).The suitable areas for Antiaris toxicaria were Guangdong,Guangxi,Hainan,Yunnan and Taiwan in China.The excellent suitable area was Guangdong,followed by Guangxi and Hainan,while the high suitable and suitable area was Guangxi.Yunnan and Taiwan were the low suitable areas.