HEAT CONDITION ANALYSIS FORZIZYPHUS MAURITIANA LAM PLANTING IN THE SOUTHEAST OF CHINA

WANG Hua; TANG Li-sheng; ZHANG Chen-hui; XIE Song-yuan; XIA Ze-xiong

doi:10.16032/j.issn.1004-4965.2017.04.011

Abstract：This paper presents analysis results of temperature index for growing Zizyphus Mauritiana Lam in Southern China.Based on the results of existing researches,we selected the following indexes:accumulate t emperature(≥ 10 ℃),annual average temperature,days with average temperature below 8 ℃ and,accumulated cold temperature(≤-2 ℃).Daily meteorological data from 241 meteorological stations of Guangdong,Guangxi and Fujian were used to analyze inter-annual and inter-decadal changes of heat conditions for growing Zizyphus Mauritiana.Spatial distribution of the inter-decadal index was also included,using spatial interpolation approaches of ArcGIS software.The result shows that the area of accumulated active temperature (≥ 10 ℃) above 6 500 ℃ ·d has increased 8.77％ and 4.05％ in this century as compared to the 1980s and 1990s,respectively;the area of annual average temperature above 18 ℃ has also increased 8.89％ and 4.69％,respectively.The northern boundary of planting Zizyphu Mauritiana Lam is shifting northward.Heat resource suitable for Zizyphus Mauritiana Lam's growth has also increased considerably.Although the effects of cold hazards in winter is less severe compared to the 1990s,the area of accumulated cold temperature (≤-2 ℃) between 0 and 5 ℃·d,which is about 85％ of the study area,has increased 1.42％ and 2.78％ respectively compared to the 1980s and 1990s.The number of days with temperature below 8 ℃ in winter showed a decreasing trend,while the accumulated cold temperature (≤-2 ℃) and the total number fluctuated greatly between years.The maximum values of days with temperature below 8 ℃ and accumulated cold temperature (≤-2 ℃) are both present in the Ningde area of Fujian.In conclusion,most areas of Guangdong and Guangxi possess the heat condition that suits for the growth of Zizyphus Mauritiana Lam,while the northern part of Guangdong,Guangxi and Fujian may still suffer from severe cold hazards and should take protection measures in planting.