气候变化对杨梅种植适宜区的影响

Predicting the influence of climate change on the suitable range for planting Myrica rubra

结合194个地理分布点和28个环境因子,利用最大熵模型(Maxent)和规则集遗传算法(GARP),对杨梅在当前和未来气候下的适宜生长区(适生区)进行模拟,并分析影响杨梅生长的主要环境因子。结果表明:杨梅适生区主要集中在长江中下游以南地区。影响杨梅适生区的主要环境因子有降水季节性(33.2%), 6—8月份日照时数(15.4%),最干季均温(14.7%)和气温年较差(7.9%)。在未来气候背景下,广东、云南、广西和海南等地区的适生区面积会显著锐减,而秦岭—淮河线地区适生区面积出现大幅度增加。总体而言,在未来气候变化背景下,杨梅的适宜分布区有向北扩张的趋势。对于丧失的适生区,如广东和广西,可采取迁地保护措施,将杨梅移植到适宜分布的区域。对秦岭—淮河线、四川盆地边缘、云贵高原等新的适生区,应该制定合理的土地利用计划,采取人工引种栽培。

Myrica rubra is an important plant economical and with medicinal value and is used for human consumption. However, factors that control the distribution of suitable habitat and related important environmental factors remain largely unknown. Based on 194 occurrence records and 28 environmental variables, we modeled the present and future suitable habitat for M.rubra using Maxent and Genetic Algorithm for Rule-set Prediction(GARP), evaluated the importance of environmental factors in shaping the species’ distribution, and predicted shifts in its distribution under various climate change scenarios. The results indicated that provinces in the south of the middle and lower reaches of the Yangtze River had high environmental suitability. Precipitation seasonality(Bio 15, 33.2% of variation), sunshine duration in June-August(15.4% of variation), mean temperature of driest quarter(Bio 9, 14.7% of variation) and temperature annual range(Bio 7, 7.9% of variation) were the key factors affecting the distribution of M.rubra. Under climate change scenarios, the availability of suitable habitat in Guangdong, Yunnan, Guangxi and Hainan decreased sharply, while that along the Qinling Huaihe line increased greatly. In general, under climate change scenarios, the range of suitable habitat expanded geographically to the north. The results of this study have important practical significance for the protection and planting planning of M.rubra. For the lost suitable areas, such as those in Guangdong and Guangxi, ex situ conservation measures can be taken to transplant M.rubra to suitably distributed habitats. For new suitable areas such as along the Qinling Huaihe line, in the edge of the Sichuan Basin and on the Yunnan Guizhou Plateau, reasonable land use planning should be conducted and artificial introduction and cultivation should be carried out.