关键词: PRRSV, PRRSV, 血清学, 检测, ELISA

Abstract: The paper aims to explore the variation characteristics of deep ground temperature in Tangshan, and provide references for studying the change of agricultural ecological environment. Based on the monthly average ground temperature data at 0.8 m, 1.6 m and 3.2 m deep of Tangshan National Basic Observation Station from 1980 to 2010, the annual and seasonal variation trend, climatic anomalous characteristics and climatic abrupt change of deep average ground temperature during the 30 years were analyzed by using statistical diagnosis method. The results showed that: the annual average ground temperature at 0.8 m, 1.6 m and 3.2 m in Tangshan had an increasing trend, the increase was least at 0.8 m deep in autumn and the most at 1.6 m deep in spring; the average ground temperature was the maximum in summer and the minimum in winter at 0.8 m and 1.6 m, and was the maximum in autumn and the minimum in spring at 3.2 m. The monthly average ground temperature was the minimum in February and the maximum in August at 0.8 m and 1.6 m, and was the minimum in March and the maximum in September at 3.2 m. The average ground temperature in spring, summer, winter and of annual had experienced two warm and two cold stages, while it had experienced two warm and one cool stages in autumn. The four seasons’and annual average ground temperature had climatic abrupt change, except the average ground temperature in spring and winter at 0.8 m and the annual average ground temperature at 3.2 m, there were anomalous warm or cool phenomena in the average ground temperature.