Global Potential Distribution Of Two Species Of Asopinae Under Climate Change Based On The Optimal Models

Arma custos and Picromerus lewisi Scott both belong to the subfamily of Asopinae.They are important natural enemies in agriculture and forestry.They can prey on a variety of pests and are of great significance to pest control.In this study,single models and ensemble models were constructed based on the known occurrence data of the two insects,combined with two types of environmental factors,climate and terrain,respectively.The performance of the models was evaluated using AUC,TSS,Boyce Index,the three evaluation indicators,and the model with the best performance was screened out to predict the potential suitable distribution areas of the two subfamily insects in the world under climate change.The purpose of this research is to theoretically provide guidance for the use of these two subfamily insects for biological control,and also provide reference for the analysis of the geographical distribution and suitability of other natural enemy insects.The main conclusions of this paper are as follows:1.The results of model evaluation based on the data of two species showed that the performance of the ensemble models were superior to that of the single models.Therefore,the ensemble models were selected as the optimal models to predict the potential distribution areas and dynamics of two species of Asopinae in the world under climate change.2.The results of climate spatial analysis showed that :(1)The niche breadth(B1=0.447,B2=0.970)of A.custos was much higher than that of P.lewisi Scott(B1=0.051,B2=0.856),and the niche overlap between the two was lower(0.28).(2)bio12(annual mean precipitation),bio16(precipitation in the wettest season),bio17(precipitation in the driest season),bio1(annual mean temperature),bio15(seasonal variation coefficient of precipitation),and alt(altitude)were the major environmental factors affecting the ecological niche of A.custos.The main environmental factors affecting the niche of P.lewisi Scotts were bio4(seasonal variation of temperature),bio6(lowest temperature in the coldest month),bio14(precipitation in the driest month),bio18(precipitation in the warmest season),alt(altitude)and slo(slope).3.According to the prediction result of the ensemble models,in the current climate,the highly suitable areas for A.custos are mainly distributed in China,the Korean Peninsula,Japan,western Turkey,central and western Europe,the United States,Argentina,and Australia;the highly suitable areas for P.lewisi Scott are mainly distributed in China,the Korean Peninsula,Japan,and some are distributed in western Europe and the United States.Under the future climate scenarios,the area of suitable areas for A.custos will decrease,and shift to the north.Russia will become their new highly suitable area;Similarly,the area of suitable distribution for P.lewisi Scott will also decrease,which will move toward the southwest.Indonesia,Africa,Central America,and southern Brazil will become the new highly suitable areas for P.lewisi Scott.