Research on the Climate Background in Arable Land Changed Areas of China

It was very important to learn the climate background in arable land changed areas of China then to estimate food production,to evaluate the balance of arable land quantity and quality,and to put in practice arable land protection and food security.In this paper,the arable land changed areas were firstly analyzed.Next,annual mean temperature,precipitation and sunshine hours were chosen to analyze the climate conditions in arable land changed areas so as to provide suggestions on land protection and economic development.The results showed that annual mean temperature,precipitation and sunshine hours in arable land decreased areas were 0.45-1.05℃ higher,56.77-79.59mm more and 45.80-98.83h less than arable land increased areas during the four periods from the end of 1980s to 2008.While annual mean temperature,precipitation and sunshine hours in areas with significant arable land reduction were 0.81-1.85℃ higher,85.69-305.26mm more and 86.96-207.85h less than those with significant arable land increase.The core part of China's arable land was gradually moving upward/northward from the end of 1980s to 2008.According to altitude,the arable land increased areas seemed to be about 0.5-1° more northward than the decreased areas,while the significantly increased areas seemed to be about 1-2° more northward than the significantly decreased areas.Otherwise,according to latitude,the arable land increased areas seemed to be about 100-200 meters higher than the decreased areas,while the significantly increased areas seemed to be about 150-350 meters higher than the significantly decreased areas.The difference in precipitation became more and more significant between the arable land decreased area and the increased area as time went on from the end of 1980s to 2008.These conclusions are important help for us to learn grain production,to evaluate the balance of arable land quantity and quality,and to readjust industrial layout in China.