Influence Of Climate Change On Potato Growth And Yield In Northeast China

Global climate change has already had negative impacts on the growth and development of potatoes,and has also led to the changes of suitable planting areas in China.Some studies used crop growth simulation models,species distribution models(SDMs),global climate models(GCMs),and other methods to assess the impacts of climate change on the growth,yield,and suitable area distribution of potato production in China.Based on these studies,management measures have been proposed to adapt to future climate change.However,more relevant studies based on species distribution models typically used only a single model to predict potato planting areas,thus the results had large uncertainties.Furthermore,some previous studies only evaluated the responses of potato growth and yield to climate change at site scale and were unable to evaluate the response of potato yield to climate change at regional scales.Therefore,this study first extracted the potential planting areas of potatoes in China for future periods based on historical observation data and land use data.Then,using five different SDMs(e.g.,MAXENT,BRT,MARS,SVM,and RF)and six different GCMs(e.g.,BCC-CSM2-MR,Can ESM5,CNRM-CM6-1,CNRM-ESM2-1,MIROC6,and MIROC-ES2L),the growth and development of potatoes were simulated in the extracted potential planting areas under four emission SSP scenarios(e.g,SSP126,SSP245,SSP370,and SSP585)and five time periods(e.g,1981-2000,2021-2040,2041-2060,2061-2080,and2080-2100)to evaluate the potential distribution of suitable areas for potato production in China.Next,based on the crop growth model DSSAT(Decision Support System for Agrotechnology Transfer)and 27 GCMs,the responses of potato phenology and yield formation to climate change under the four emission scenarios and in the five time periods were predicted in Northeast China.Finally,the responses of total potato production to climate change were evaluated considering the changes in distribution of suitable areas of potato production in China.Some main results and conclusions of the study were drawn as follows.(1)Based on the global climate models,the temporal and spatial variations of meteorological factors and droughts in historical and future periods were analyzed.Through literature review and statistical analysis,the study identified the potential planting areas of potatoes in China.Based on the MK trend test,it was found that the meteorological factors in the historical baseline period(1981-2000)and future period(2021-2100)in China showed an increasing trend in the potential potato planting areas.In the future,with the increase of emission scenarios,the frequency of various levels of droughts would increase.The frequency of moderate and severe droughts would increase dramatically.Southwest China,Gansu Province,and Northeast China,will be greatly affected by meteorological droughts.(2)Based on the integrated SDMs,the temporal and spatial distribution characteristics of potato climate-suitable areas were analyzed.The main meteorological factors affecting the climate suitability of Chinese potatoes were the precipitation in the wettest month,the highest temperature in the warmest month,and the average temperature in the coldest quarter,with contribution rates of 54.7%,21.4%,and 18.1% to the simulation results,respectively.With the increase of greenhouse gas emission levels,the areas of high suitability for potato cultivation in the potential planting areas would decrease in the future.In terms of spatial distribution,the high-suitable areas for potato cultivation in China were mainly concentrated in the Northeast,Gansu Province,and Southwest regions of China.From the temporal perspective,regions such as Gansu,Northeast,and Southwest would be greatly affected by future climate change.And there would be a clear trend of decrease in climate suitability for potato cultivation.(3)Based on the crop growth simulation model,the influences of climate change on the growth and yield of potato in Northeast China were evaluated.The study used field experiment data to calibrate the potato growth simulation model of SUBSTOR-Potato in DSSAT,which was driven by historical weather data obtained from 44 different meteorological stations in Northeast China during the base years of 1981-2000.Then,the SUBSTOR-Potato model was driven by future climatic data obtained from the 27 GCMs in the CMIP6,to predict potato yields in the region across four time periods of 2021-2040,2041-2060,2061-2080,and 2081-2100 under four different emission scenarios(SSP126,SSP245,SSP370,and SSP585).Generally,potato production in Northeast China was expected to increase in the future.Higher accumulated temperature and radiation during potato growing season would favor potato yield increase.However,areas with less accumulated rainfall during potato growing season were expected to experience a decline in potato yields.