不同气候情景下木梨潜在地理分布格局变化的预测

Prediction of potential geographical distribution patterns of Pyrus xerophila under different climate scenarios

木梨的抗旱、抗寒、抗盐碱和抗梨锈病的能力较强,是我国西北地区梨的主要砧木类型之一,具有较高的生产价值。但目前其生境破坏较为严重。预测不同气候情景下木梨的地理分布可为木梨资源的合理开发利用及多样性保护提供重要的科学依据。本研究利用木梨全面且精确的分布信息和高分辨率环境数据,基于MaxEnt模型和ArcGIS空间分析,构建其当代及未来(2050和2070年)的潜在空间分布格局,评价环境因子对分布模型的重要性。结果表明:目前木梨适宜生境面积为33.2万km2,主要位于我国青海东部、甘肃南部、宁夏南部、陕西中部、山西南部和河南西部地区,紫外线辐射量最少月份的平均紫外线量和海拔是限制其分布的主要环境因子。随着全球气候变暖,在不同CO2浓度情景下,2050和2070年木梨的潜在适生境将逐渐减少,应加强对木梨群体的实时监测。

Pyrus xerophila has strong resistance to drought,cold,salt,and rust.It is one of the main rootstock types of pear in Northwest China,with high production value.However,its habitat is seriously damaged.The prediction of the geographical distribution of P.xerophila under different climate scenarios will provide important scientific basis for rational development and utilization of resources and the protection of diversity.Based on MaxEnt model and ArcGIS spatial analysis,the potential spatial distribution pattern of P.xerophila in the current and future(2050,2070)was constructed using comprehensive and accurate distribution records and high-resolution environmental data,and the relative importance of environmental factors was evaluated.The results showed that the suitable habitat area of P.xerophila was 3.32×105 km2,mainly located in eastern Qinghai,southern Gansu,southern Ningxia,central Shaanxi,southern Shanxi and western Henan.Mean UV-B of the month with lowest UV-B and altitude were identified as the critical factors shaping habitat availability for P.xerophila.Overall,with global warming,the potential habitat for P.xerophila might decrease in 2050 and 2070 under different CO2 climate scenarios.Real-time monitoring of P.xerophila populations should be enhanced.