趋势面分析在国境口岸蝇类密度监测中应用

Application of Trend-surface Analysis on Surveillance of Fly Density at Frontier Ports

〔目的〕对国境口岸蝇类年平均密度分布特点以及年平均气温与降雨量对其密度影响程度进行探索研究,了解国境口岸蝇类密度地理空间的分布规律及气候因素对其影响的特点。〔方法〕对36个口岸蝇类年平均密度资料应用趋势面及残差分析法进行分析。〔结果〕建立经纬度的蝇密度三阶趋势面函数(拟合优度为72.23%)和气温降雨量的蝇密度三阶趋势面函数(拟合优度为63.30%),残差分析显示:以上两种函数的正残差值共同高于界值的有日照港、宁德、马尾口岸;共同低于负残差界值的有扬州港和福清江阴港。〔结论〕三阶趋势面函数能较好地描述蝇密度口岸分布;蝇密度地理坐标空间分布规律是东南地域密度趋高,气温降雨量的蝇密度分布规律显示一定的气温加适宜的降雨量是密度趋高的关键;残差分析中某些特殊口岸可能存在不良因素使蝇类密度趋高。

Objective To explore the fly density in longitude and latitude as well as in temperature and rainfall of frontier ports in China,and to find out the characteristics on the geographic space distribution and climatic influence facfors on fly density.Methods The data of annual average fly density collected from 36 frontier ports was analyzed by trend-surface analysis and residuals analysis.Results Third-order trend-surface function（goodness of fit 72.63%） of fly density in longitude and latitude and third-order trend-surface function（goodness of fit 63.30%）of fly density in temperature and rainfall were adapted to established.Residual analysis suggests that the ports exceeding the boundary of positive residuals values were Rizhao Port,Ningde and Mawei Port,and the ports with negative ones were Yangzhou Port and Fuqing Jiangyin Ports.Conclusion Three-order trend-surface functions can be suited to describe the distribution of fly densities at frontier ports.The geographic distribution trend of fly average densities in longitude and latitude shows that the density is higher in the southeastern China,and the fly density distribution in temperature and rainfall shows that the key to the higher trend in the southeast is the proper temperature with fit rainfall.There are some risk factors to higher the fly density at some ports with higher positive residual.