Research Of Sustainable Use Of Cultivated Land Under The Driving Forces Of Climate Change And Urbanization

Based on the urban data and climate data from 1960 to 2014,the potential productivity of cultivated land was computed in this article and the effect of climate change on the potential productivity was analyzed.To find the main driving forces affecting cultivated land change during the process of urbanization,the analysis of urbanization change and cultivated land change were also conducted.Combining the change of potential productivity and cultivated land area,this article was aim to discuss the change of total potential production under the driving forces of climate change and urbanization.This research can provide scientific basis to sustainable use of cultivated land in Nanjing.The results are as follows:(1)During the period of 1964 to 2014,the extreme high temperature had no obvious increasing trend,the extreme low temperature and average temperature increased obviously.The decreasing climatic factors were average relative humidity,total solar radiation and sunshine hours.The amount of precipitation had no obvious change trend,but it had strong oscillations during the time of decade.The photosynthetic potential and light-heat potential production had decreasing trend,the climatic potential and climatic-land potential production had no obvious trend,but they had strong oscillations.(2)The photosynthetic potential production had positive correlation with average humidity and total solar radiation.The light-heat potential production had obvious linear relation with average temperature and sunshine hours.The climatic potential and climatic-land potential production had positive correlation with precipitation and sunshine hours but they had negative correlation with average temperature.(3)The urbanization level had increasing trend in Nanjing during the 55 years.The process of urbanization could be divided into 5 periods:counter urbanization period,redevelopment period,steady development period and rapid development period.The area of cultivated land had decreasing trend during every period we divided.(4)The process of urbanization had obvious negative effect on the area of cultivated land since 1971.They had low coordination degree between each other and the degree had decreasing trend during the 55 years.(5)The total photosynthetic and light-heat potential production decreased,the total climatic potential production had strong oscillations.Average temperature,sunshine hours,precipitation and total solar radiation are the main climatic driving forces that affected the sustainable use of cultivated land.The high level of urbanization and human life,the advance of agriculture science and technology,the development of economy and the city expanding were urbanization driving forces that affected the sustainable use of cultivated land in Nanjing.