湖北钉螺分布与年极端低气温的关系分析

Relationships between distribution of Oncomelania hupensis and extreme air temperature in a year

目的探讨钉螺分布与年极端低气温的关系,为进一步的研究提供理论依据。方法选取上海市、江苏、浙江、安徽、江西、湖北、湖南、河北、河南、山东、山西、陕西、四川省61个气象站的气温数据,以北纬34°为界,通过两者的统计分布来确定钉螺可疑分布区的温度范围,并研究有螺区与无螺区在该范围内持续时间的差异。结果钉螺可疑分布区的温度范围为-7.6～1.5℃,无螺区有75%的气象站其年极端低气温低于-7.6℃,有螺区有19%的气象站其年极端低气温高于1.5℃;有螺区与无螺区在该范围内时间的差异无显著性(P=0.53),但无螺区在相应区间内的时间均多于有螺区。结论钉螺在年极端低气温低于-7.6℃的地区不适宜生存,温度是阻止钉螺北移的重要条件。

Objective To study the relationship between the distribution of Oncomelania hupensis and extreme air temperature in a year so as to provide theoretical support for laboratory research. Methods Sixty-one weather stations, distributed in Shanghai, Jiangsu, Zhejiang, Anhui, Jiangxi, Hubei, Hunan, Hebei, Henan, Shandong, Shanxi, Shaanxi, Sichuan, were selected as research stations. North latitude 34° was set as the boundary of Oncornelania hupensis＇s distribution, and the relationship between the distribution of Oncomelania hupensis and extreme air temperature in a year was studied with the statistical method. At the same time, the temperature range where Oncomelania hupensis may survive or not survive and the time difference in the temperature range were studied. Results The temperature range that Oncomelania hupensis may survive or not sur vive was -7.6-1.5 ℃. The extreme air temperature in a year was below -7.6 ℃ in 75% of weather stations in the area where Oncomelania hupensis can＇t survive,and the extreme air temperature in a year was above 1.5 ℃ in 19% of weather stations in the area where Oncomelania hupensis can survive. Their time difference in the temperature range was not statistically significant, but the time in the area where Oncomelania hupensis may not survive was longer than that in the area where Oncomelania hupensis may survive. Conclusion Oncomelania hupensis is not fit for surviving if its extreme air temperature in a year is below --7.6 ℃. Extreme air temperature is the important factor that prevents Oncomelania hupensis from moving to the northern area.