Study On Potato Climatic Suitability And Influence Of Yield Under Climate Change In Northern China

Climate change is likely to have a tremendous impact on agricultural production all over the world.As one of the world's major food crops and important economic crops,potatoes are closely related to climatic variables.The original intention of this study is to understand the regional climate resources,to protect the potato industry in the northern China and to reasonable use local climate resources.Considering the interaction between crop and climatic variables,this research use and improve statistical methods such as qualitative and quantitative analysis of climate resources in northern China,potato climatic suitability model and climate yield separation method to discuss the relationship between climate change,potato growth and yield,to analysis the climatic suitability in potato production area and find out the possible adverse effects on potato production brought by climate change.The results showed that:(1)The dominant climatic variables(significant positive correlation and negative correlation)of potato production in northern China were temperature,precipitation,sun hours.Secondary climatic variables were potential evapotranspiration,solar radiation,etc.(2)In fifty years,average temperature increased obviously,and it was from17.52? in 1965 to 18.51? in 2014.Sun hours and solar radiation decreased significantly,and the other two climatic variables changed slightly.Specifically speaking,temperature increasing period was mainly about 70 and 90 s.In this period,average temperature change was unstable and had a great rangeability;For annual precipitation,it showed a small decline trend and an obvious interannual fluctuation.In terms of spatial distribution,the high precipitation area was shrunk,but the total annual precipitation increased;Sun hours was in a downward trend,it was from 8.67 hours in 1965 to 7.33 hours in 2014.In the twentieth Century 60-70 s,the decline was most obvious;Potential evapotranspiration changed less.In addition,the amount of solar radiation has been declining.(3)Temperature suitability and precipitation suitability were decreasing in theview of time line,down from 0.876 to 0.870,0.461 to 0.443 respectively.The illumination suitability rose from 0.732 to 0.767 and comprehensive suitability increased from 0.704 to 0.708;The temperature,precipitation,illumination and comprehensive suitable planting areas had a tendency to expand westward and southward in space distribution.This would be beneficial to the potato production in the vast area;From the point of view of the growth period,temperature suitability degree,illumination suitability and comprehensive suitability in seeding-emergence period showed an upward trend,emergence-flowering period showed a downward trend except illumination suitability and comprehensive suitability,and they also showed a downward trend during flowering-mature period excepted illumination suitability and comprehensive suitability;Above all,the climate suitability generally raised slightly in fluctuation,and it has increased by 0.01.Climate change played a beneficial role in potato production.However,precipitation was still the main limit climatic variable to potato in the study area.(4)In terms of potato growth period,with the increase of average annual temperature,the seeding period was gradually ahead of time,but emergence of seedling,flowering and mature period was delayed.With the increase of annual precipitation,the seeding period was delayed,and the other growth periods were ahead of time.Specifically,the precipitation effect on the growth period is greater than that of temperature.While the average temperature rise 1 degrees,sowing period was advanced 0.51 days,the flowering period was delayed 0.15 days,period of emergence was delayed 0.38 days and maturity period was delayed 0.25 days.While the annual average precipitation increase 1mm,seeding period was delayed 0.15 days,time of emergence was 0.23 days ahead of time,flowering period was 1.01 days ahead of time,and maturity period was advanced 0.40 days.(5)The regional climate change effect on potato yield was significant,and it presented a difference between time and region.The climate had a positive impact mainly.1985-2014 the climate impact factors of Gansu province fluctuate were between-0.20-0.20,and it fluctuated between-0.30-0.80 in Inner Mongolia.In contrast,Inner Mongolia potato production was more affected by climate change thanthat in Gansu and it's range more intensely.Climate impact factors and climate yield were gradually approaching 0,climatic conditions control became slightly on potato in the two provinces.(6)Using Calman filter method to separate climate yield had better effect and applicability.On the basis of the 5 year moving average method,the two methods passed the significance test.In addition,the correlation between climate yield and main climatic factors separated by the Calman filter method was very significant.Their correlation coefficients were 0.328,0.302,and-0.522,respectively.Climate yield change in adjacent cities also showed correlation.On the other hand,climate yield was also consistent with the historical meteorological data and potato growth demand,it showed that the climate yield simulated by Calman filter method was consistent with actual situation,and this method can simulate climate yield better.