Potential Suitability Assessment of Bursaphelenchus xylophilus in China

Potential suitable area for the pine wood nematodes, Bursaphelenchus xylophilus were described quantitatively. According to its biological characteristics and relationship between its development and the environment, five key factors were chosen, namely yearly mean temperature, the mean temperature of July, June and August, altitude, days above 25 ℃ and precipitation. Their subordination functions were defined with math method of synthetic assessment on fuzzy mathematics. Climatic data of 639 sites obtained from State Weather Administration were processed by program of Qbasic 6.0 in order to get its subordination value, and comprehensive suitable value of every site was calculated by creation of fuzzy judgment matrix. Finally MapInfo 7.5 software was adopted for data collection, processing and analysis to make thematic map, five environmental types were graded according to comprehensive suitable value.