Changes Of Light, Heat, Water Resources And Effect On Corn Potential Productivity In Xiliao River Plain

Currently, climate change is one of the serious environmrntal problems of the human facing, Global climate warming has more and more serious impacts on agriculture.In view of climate change has evident regional and the fact of the xiliao river plain is the main maize production region of inner mongolia, Taking the data from weather station in tongliao, kailu and zhalute as representative, applying climate change trend analysis approach and abrupt climate change test approach to study from 1951 to 2008 evolution of light, heat, water resources and effection on corn potential productivity in Xiliao river plain, and analysis the variety of surface water, ground water and agricultural water of study area. On the basis, calculate the light-temperature potential productivity, climatic potential Productivity, photosynthetic productive potential of corn according the mechanism method by year, analysis the trend of the light-temperature potential productivity. climatic potential productivity. photosynthetic productive potential of corn and study the countermeasures of corn production adapt to climate change. The main research achievements are as follows:There was a decreasing trend of the sunshine duration and sunshine percentage of year and growing season from 1951 to 2008. Sunshine duration of year and growing season decrease rate is respectively 6.56h·(10a)-1 and 9.75h·(10a)-1. The sunshine percentage show double wave variation.There was a increasing trend of annually mean temperature, annual minimum temperature, maximum temperature, extremely lowest temperature, extreme maximum air temperature, frost-free period, the day numbers of duration and corresponding accumulated temperature. In which, just extreme maximum temperature of average intervals with daily temperature≥5℃did not pass significance test. In the process of climatic warming, the trend of lowest temperature warming is the most obvious. the trend coefficient is 0.85 (P< 0.01); There is a decreasing tendency in intervals with daily temperature≤-20℃and≥30℃. In which, the tendency is obvious of intervals with daily temperature≤-20℃, the trend coefficient is 0.61 (P<0.01), annual mean temperature had mutations around 1991.There was a decreasing trend of the annual precipitation, annual evaporation, days with daily area rainfall from 1951 to 2008. The annual precipitation show double wave variation, there were two mutations respectively in 1971 and 1995, and both from pluvial period to less rain ones; evaporation deceases in fluctuation. the trend coefficient is 0.33 (P <0.01). After the 1978, there was a obvious increasing trend of groundwater depth,areas of groundwater over-exploited and funnel region; And a decreaing trend of main river runoff; the tongliao station of Xiliao river is entering continuous zero flow in the 21(st) Century; agricultural water consumption overall showed increasing tendency, the ratio of agricultural water consumption showed decreasing tendency.There was a decreasing trend of the photosynthetic productive potential, climatic potential Productivity from 1951 to 2008. The trend coefficient did not pass significance test; and a increasing trend of light-temperature potential productivity. but the trend is not obvious:the difference value of light-temperature potential productivity and light-temperature potential productivity reduced gradually.In view of obvious climate warming in Xi Liaohe River Plain, measures for maize production should be taken include early sowing at an appropriate time, late picking. increasing the proportion of late-maturing varieties and multiple cropping silage corn after wheat, to achieve the full advantage of the increasing heat because of climate changing. In the background of precipitation decreasing. by extending water-saving agricultural technology and carring out artificial precipitation enhancement. it is can cope with droughts of intensification, and fully excavates the light-temperature potential.