Potential Threat Analysis Of Typical Invasive Organisms In Agroecosystems And Human Settlements Based On Species Distribution Model

In recent years,due to global climate change and frequent human activities,a large number of species have broken the original restrictions and become invasive species,causing serious ecological damage and economic losses to the invasive places.The emergence of many invasive species has brought great impact on human production and life,among which the agricultural production environment and human living environment,which ensure people’s basic survival and life,have been the most obvious impact.In this study,four typical species affecting human production and life were selected,including invasive insect desert locust(S.gregaria),invasive weed A.tauschii and A.artemisiifolia which affecting agricultural production,and S.invicta,which typical invasive species affecting agro-ecosystem and human settlement environment.To analyse the driving factors are evaluated and analyzed based on species distribution Models(SDMs).The main conclusions are as follows:(1)This study analyzed the distribution pattern of desert locust and its driving factors under the current and future scenarios and tested the niche conservatism of desert locust.The results showed that climate was the most important factor affecting the distribution of desert locust,among which the min temperature of coldest month,annual precipitation,and mean temperature of the driestquarter had the most significant effects.Some areas with little or no distribution of desert locust(such as East Asia,Australia,etc.)show higher habitat suitability in the future,and adjacent areas with high suitability may become potential dispersal paths of desert locust.The results of niche test showed that the niche width of the invading desert locust was slightly larger than the original niche,but the niche was still conservative,which may explain the periodicity of the desert locust outbreak,rather than the continuous occurrence in the invading desert locust.Therefore,in the future,continuous attention should be paid to areas with high habitat suitability of desert locust,especially those with no or small distribution at present,as well as continuous monitoring of possible niche shifts,so as to form an effective long-term mechanism for desert locust control.(2)This study analyzed the global potential distribution areas of A.tauschii and A.artemisiifolia and the driving factors and combined with the global cultivated land distribution to evaluate the potential threatened cultivated land areas.The results showed that the main factors affecting the distribution of A.tauschii were the min temperature of coldest month and the precipitation of warmest quarter,while the main factors affecting the distribution of A.artemisiifolia were the precipitation of driest month and annual mean temperature.The suitable habitat area of A.tauschii decreased under both scenarios,and the suitable habitat area of A.artemisiifolia increased under RCP8.5 scenario.The overlap area of A.tauschii and agricultural land decreased in both scenarios,while that of A.artemisiifolia increased in RCP8.5 scenario.The results showed that with the increase of temperature under future climate change,the distribution area of A.tauschii will gradually decrease,and the potential threat to agricultural farmland will also decrease,while the distribution area of A.artemisiifolia increased significantly under the significant increase of temperature in the future,and the potential threat to future agricultural land also increased significantly.(3)This study analyzed the potential suitable distribution area of S.invicta in China and its overlap with population density,so as to evaluate the risk area of conflict between S.invicta and human and analyzed the driving factors affecting its distribution and niche conservatism.The results showed that climate was the most important ecological factor affecting the distribution of S.invicta,among which precipitation of driest quarter,mean temperature of warmest quarter and temperature seasonality were the most important factors.The potential suitable habitats for S.invicta were mainly concentrated in southeast and central China,where the population density was high and most of them were at high risk of human conflict.Although the niche of S.invicta is still conservative,the niche width of the invasion area has widened compared with the original area.The invasion of S.invicta is strongly affected by precipitation and temperature,and it has obvious conflict with the human settlements in southeast provinces and some central regions,and the risk evaluation is high.Therefore,the corresponding regions should pay more attention to the prevention and control of S.invicta in future.