Regionalization Of Guangxi For Cassava Growing Based On Climate

Cassava is one of advantageous crops in Guangxi Province, its growing and developing is attached great importance by the agricultural sector of the government. The climate in Guangxi is suitable for cassava production. However, not all counties are beneficial for growing cassava because climate varied in Guangxi. Thus, suitability evaluation for cassava growing is needed. Climate data for all counties in Guangxi in 2012 and 2013 were collected and analyzed. Four indices, including annual mean temperature (AMT), annual accumulated temperature(≥10℃, AAT), annual precipitation (AAP) and annual sunshine duration (ASD) in each county, were selected for the suitability evaluation of cassava growing. By the Summation scoring method, the suitability for every index is scored and classified into four grades:"Optimum", "Suitable", "Less suitable" and "Not suitable". Then the scores for every index are summed as a total score for every county. And the total score is connected to its administration zone in Geographical information system (GIS) software (Quantum GIS, V1.8.0) through key fields. Then the regionalization results were drafted and displayed by the GIS software.The regionalization results are as follows:1) The "Optimum" region is centralized besides 24°N, including the counties of Pingnan, Guigang, Fusui, Longzhou, Hepu, Beihai, Tianyang et al., which cover 698 671 km2, about 33.01% of Guangxi Autonomous Region.2) The "Suitable" region is beside the boundary of the "Optimum" region, including the counties of Wuming, Guiping and Shanglin which are at the middle of the boundary, and the counties of Baise, Yizhou, Pingle et al. which are at the north of the boundary. The region covers 576 280 km2, which is about 27.22% of Guangxi Autonomous Region.3) The "Less suitable" region locates in the north of the "Suitable" region, including the counties of Hezhou, Lingui, Yongfu, Huanjiang, Debao, Napo and Xilin, covers 726 393 km2, about 34.32% of Guangxi Autonomous Region.4) The "Unsuitable" region is consisted of the counties of Leye, Nandan, Ziyuan, Jinxiu and other counties with similar latitude which are mainly cold mountain areas. This region covers 9 500 km2, which is about 4.47% of Guangxi Autonomous Region.In conclusion, evaluated by climate, most areas of Guangxi are suitable for cassava growing, including the "Optimum" region and the "Suitable" regions which locate at the south of 24.5°N and cover 60.23% of Guangxi, the "Less suitable" region which locate at the north of Guangxi and cover 34.32% of Guangxi. Only about 4.47% areas of Guangxi is unsuitable for cassava growing. The results are displayed by GIS software.