Effects Of Climate Change On Climatic Productive Potentialities Of Winter Wheat In North Of China

Under the background of global climatic warming,climate has more and more evident impacts on agriculture and crop potential productivity.In order to study the impacts of climatic changes on winter wheat production in North China,55 meteorological stations were chosen for the research and involved meteorological data are sunshine hours,temperature,precipitation and additionally,the yield data of winter wheat was collected.We analyzed the spatial-temporal evolution characteristic of sunshine hours,temperature,and precipitation from 1961 to2004 in Northern China.Based on understanding influence of water on the productive potentialities of winter wheat in sami-humid,sami-arid areas of northern China under natural climate condition, the" correction step by step" is used to calculate photosynthesis potential productivity, photo-temperature productivity and climate productive potentialities,during which the new formula" Penman-Monteith" commended by FAO is used to calculate the water requirement of winter wheat.The main research results were summarized as follows:(1)There was an obvious increasing trend in the annual mean tempera'rare in the recent 44 years,increased with 0.26℃·(10a)^-1, Annual precipitation had a descending trend,decreased with -21.43mm·(10a)^-1,Furthermore, variation trends of sunshine hours were similar to precipitation,decreased with -77.74h·(10a)^-1. (2)There was an obvious descending trend in the photosynthesis potential productivity in the recent 44 years,decreased with -3094.2kg·(10 a)^-1,photo-temperature productivity and climate productive potentialities have obvious increasing trend.Photo-temperature productivity increased with965.2kg·hm^-2.(10a)^-1,climate productive potentialities increased with 658.3kg·hm^-2·(10 a)^-1. From the space and time change characteristics,photo-temperature productivity and climate productive potentialities have obvious zonal distribution,photosynthesis potential productivity zonal distribution is not obvious.(3)Sunshine hours,temperature changes and the potential production have positive correlation,Sunshine hours is the main factor which influence photosynthesis potential productivity and temperature is the primary factors which effect photo-temperature productivity.In the recent 44 years,along with sunshine hours' reduction,the photosynthesis potential productivity has a decreasing trend,along with temperature increases; the photo-temperature productivity has an upward trend.We calculate relative change rate, variance coefficient,reduction of product and the deficiency rate of water are used as indexes to analyze dynamic change of water and climatic productive potentialities,the deficiency rate of water and potential production have same distribution.(4)By three factors on the potential production,determine the sunshine hour is the major factor of potential production;overall evaluation temperature and precipitation on the impact of potential.Production we know: Cold-wetting climate is the most advantageous for crop production in the Northern China.