云贵高原红花龙胆生态适宜性区划研究

Ecology Suitability Study of Gentiana rhodantha in Yunnan-Guizhou Plateau

目的预测红花龙胆(Gentiana rhodantha)在云南、贵州的潜在适生区,研究物种分布与生态因子间的相互关系,探讨气候和土壤条件对药材特定和整体化学成分的影响作用。方法最大熵模型(MaxEnt)和地理信息系统(GIS)用于预测红花龙胆潜在地理分布;超高效液相色谱法用于建立红花龙胆不同部位UPLC指纹图谱;Pearson相关性分析和逐步回归分析研究化学成分含量变化与生态因子间的相互关系。结果 MaxEnt模型训练集和测试集AUC值分别为0.919和0.915,表明模型预测结果准确,可信度高。分布区模拟结果显示,影响红花龙胆分布的主要生态因子为:年均温度变化范围(最适宜范围:16.0~27.0℃)、昼夜温差月均值(最适宜范围:8.5~11.6℃)、6月平均降水量(最适宜范围:200~400 mm)、9月平均降水量(最适宜范围:90~125 mm)、6月平均最高气温(最适宜范围:21.0~27.0℃)、温度季节性变化方差(最适宜范围:4 000~5 200)、10月平均降水量(最适宜范围:65~110 mm)、7月平均最低气温(最适宜范围:14.5~20.5℃)、1月平均最高气温(最适宜范围:14.5~25.5℃)、土壤酸碱度(最适宜范围:pH<5)、4月平均降水量(最适宜范围:14.5~25.5 mm)。相关性分析显示,地下与地上部位芒果苷含量、化学成分总含量、化学成分根茎比与植株生长期温度、降水及上层土壤理化特性相关性显著(P<0.05或P<0.01),与生境适宜度值呈显著(P<0.05)或极显著(P<0.01)的负相关;6~8月的降水、温度变化及上层土壤酸碱度、阳离子交换量是影响药材有效成分积累的关键生态因子。结论云贵高原红花龙胆最适宜的生长区位于云南中部和滇西北,贵州黔东南和黔南地区。

OBJECTIVE To predict the potential geographical distribution of Gentiana rhodantha and study the relationship between species distribution,chemical compounds content and ecological factors in Yunnan-Guizhou Plateau.METHODS MaxEnt modeling combined with geographic information system（GIS） was used to predict the potential geographical distribution of G.rhodantha.Ultra performance liquid chromatography（UPLC） was used to establish the UPLC fingerprints of different parts of medicinal materials.Pearson correlation analysis and stepwise regression analysis were used to analyze the relationship between various chemical compounds and ecological factors.RESULTS The AUC of the ROC curves of the training data and test data were 0.919 and 0.915,respectively,which indicated that the predictive results with the maximum model were highly precise and exact.The results of species distribution modeling showed that the main environmental factors determining the potential distribution were annual temperature range（the most suitable range：16.0-27.0℃）,mean diurnal range（the most suitable range：8.5-（-1）1.6℃）,average monthly precipitation of June（the most suitable range：200-400 mm）,average monthly precipitation of September（the most suitable range：90-（-1）25 mm）,average monthly maximum temperature of June（the most suitable range：21.0-27.0℃）,temperature seasonality（the most suitable range：4 000-5 200）,average monthly precipitation of October（the most suitable range：65-（-1）10℃）,average monthly minimum temperature of July（the most suitable range：14.5-20.5℃）,average monthly maximum temperature of January（the most suitable range：14.5-25.5℃）,subsoil pH（the most suitable range：pH5）,and average monthly precipitation of April（the most suitable range：14.5-25.5 mm）.Correlation analysis showed that the contents of mangiferin,total compounds and their ratios of aerial part and underground part had significant relationship with temperature,precipitation and hysico-chemical properties of top soil（P〈0.05 or P〈0.01） and had significant negative（P〈0.05） or most significant negative relationship with habitat suitability（P〈0.01）.The variation of temperature and precipitation of June to August and subsoil pH subsoil CEC were the key ecological factors of accumulation of the chemical compounds in G.rhodantha.CONCLUSION The best growing areas for G.rhodantha are mainly located in Middle and West Yunnan,Southeast and South Guizhou.