Identification of suitable distribution areas for Torreya grandis in Hunan province based on the MaxEnt model
[Objective]Torreya grandis is a rare economic tree species endemic to China.Predicting the suitable distribution area of T.grandis in Hunan province and exploring the dominant environmental factors affecting the distribution of T.grandis will help to formulate the conservation strategy for the species and select the suitable sites for development and utilization.[Method]193 field survey points of T.grandis in Hunan province were taken,22 environmental variables affecting the distribution of T.grandis were selected,and the MaxEnt model was used in conjunction with the ArcGIS 10.7 software to analyze the dominant environmental factors affecting the distribution of T.grandis and predict the suitable distribution areas of the species in Hunan province.[Result]1)the average AUC value of 10 cross-validated fits under the ROC curve for the training dataset was 0.914,and the average AUC value of 10 cross-validated fits for the test dataset was 0.867,with a standard deviation of 0.074,which made the model prediction results accurate;2)Altitude,slope,mean temperature in the driest quarter,and precipitation of warmest quarter are the four key factors limiting T.grandis's current potential suitable distribution,with percentage contributions of 29.40,16.90,8.60,and 7.30,respectively;and replacement importance of 53.30,14.60,5.70,and 6.50,respectively.3)The total area of T.grandis suitable area in Hunan province was 9.114×104 km2,and the areas of high,medium and low suitable distribution areas were 0.872×104 km2,2.659×104 km2 and 5.583×104 km2,respectively;the suitable distribution areas were mainly concentrated in the central,western and southeastern parts of Hunan province,and the high and medium suitable distribution areas were concentrated in the northern,southern and southwestern part of Shaoyang,southwestern Yiyang,central and southern Yongzhou,and the central and southern part of Yongzhou,and the southwestern part of Yiyang,and the southwestern part of Yongzhou.The suitable distribution areas were mainly concentrated in the central and southeastern areas of Hunan,with high and medium suitable distribution areas concentrated in the northern,southern and southwestern parts of Shaoyang,Yiyang,the central and southern parts of Yongzhou,the northwestern part of Loudi and the central and southern parts of Huaihua.[Conclusion]Topography,climate and other factors affect the geographical distribution pattern of Torreya grandis in Hunan Province.The valley areas of Shaoyang,Yiyang,Yongzhou,Loudi and Huaihua with low altitude,relatively flat terrain and cool climate may be suitable for the introduction and cultivation of Torreya grandis.
MaxEnt modelTorreya grandissuitable distribution areaimpact factor
NETL
NSTL
万方数据
