Climatic Regionalization Of Winter Planting Potato Based On GIS In Guangxi

Because of the unique climatic conditions and plenty of the fallow fields in winter. Guangxi province becomes the major production base in winter potato planted in China. It is significant to carry climatic suitability regionalization of the winter planting potato in Guangxi province for giving full play to ascendancy of climatic resources, regulating the planting distribution, achieving high yield and promoting the development of winter planting potato economy. According to the requirement of potato to climatic conditions, basing on the climatic data of Guangxi in winter, combining with the previous studies and the realistic production data, this study selected the winter planting potato zoning factors, included:winter minimum temperature of guarantee rate higher than80percent, frost days, monthly mean temperature in January and February, accumulated temperature of daily mean temperature higher than5℃of guarantee rate higher than80percent, days of daily mean temperature higher than10℃of guarantee rate higher than80percent, precipitation in March and April. Spatial calculating model of the indices was built by the regress method of mathematical statistic. Spatial analyzing model of climatic regionalization indices included the station latitude, longitude and altitude, realized the precise comprehensive agricultural climatic regionalization by using the principles of Geographical Information System that broke through the limited in traditional regionalization. The results were be more useful and reality, to provide scientific basis of achieving high quantity and quality production and optimizing the industrial structure. Each index was divided into most feasible, feasible,next to feasible and out of feasible.According to the regionalization indices, by GIS technology and small grid calculating method of the climatic resources, analyzed climatic regionalization of winter planting potato in Guangxi and discussed winter planting potato planting suitable climate regionalization of possible responses to future climate change. In this paper following contents are researched:1、Geographical distribution of agro-climatic resources during the winter farming season in Guangxi province:the mean temperature was gradually reduced from South to North. The temperature in valley and plain was higher than that in mountain. The accumulated temperature distribution was the same with the mean temperature. Heat resource mainly distributed in the South and Youjiang valley area. The precipitation in the East overtook that of the West, and in the North overtook that of the South. The precipitation mainly distributed in the East and Northeast, but was lower in the valley areas and Northwest of Guangxi. Sunshine hours were more in the South, valley and plain, but lower in the North and mountain. Light resources mainly distributed in the Southeast, Northwest and South coastal area.2、Variation characteristics of agro-climatic resources during the winter farming season in Guangxi province:the trend of temperature rose obviously, the mean minimum temperature showed a significant ascending. Monthly mean temperature and mean maximum temperature in East and South Guangxi increased in evidence. The mean minimum temperature, days(daily mean temperature equal to or higher than10℃) in West and North Guangxi increased substantially. The precipitation showed a slightly increasing trend, but a significant in East and Southwest. The precipitation in South Guangxi, Northwest Guangxi and East of Hechi city reduced. Sunshine hours showed a declining trend, a significant reducing in Hengxian county, NanNing city, Laibin city and Yulin city.3、The results showed that the most feasible areas were mainly located in the South of Guangxi coastal region, Southeast of Guangxi and counties of Nanning city. These areas were the emphatic development areas of winter planting potato and should be planting large-scale to make full use of its climate resources and improve the economic benefits. Feasible areas were mainly distributed in the Southeast and Southwest of Guangxi. These areas should be planting cold resistance potato of early and middle maturing, besides strengthen water retention and irrigation. Next to feasible areas included Southeast of Guangxi, Hechi city and counties of Youjiang valley. These areas could be some risks to plant winter planting potato, but planting cold and drought resistance potato appropriately. Out of feasible areas were mainly consisted of the northern region of middle of Guangxi and mountains of Baise city.4、 Under the background of climate change, In the next30years, the most feasible, feasible and next to feasible areas obvious trend of moving to the north, to low latitude high altitude areas, meanwhile, the area is also gradually increased, but out of feasible areas reduce substantially. So we should adjust the planting distributing of winter planting potato, expand planting areas, optimize the industrial structure.