农田生态环境变迁与某些农作物病虫害发展变化趋势

通过对河南省新乡地区历年资料分析表明，近40年来该地区主要农业生态环境要素有明显变化。如年日照时数和年均风速逐渐下降，而相对湿度呈上升趋势，进而引起地区性的水面蒸发量下降。气象要素的变化及灌溉量、施N量的增加，促使某些主要农作物病虫害加重，故培育高抗病虫害能力的作物新品种，实施节水灌溉及经济合理施用N肥对缓解该地区的病虫危害将十分有益。

Changes of eco-environment of farmland and development of some crops diseases and insect pests

Based on long-term statistical data provided by specific department in Xinxiang region of Henan province,it is showed that the main factors related with agricultural eco-environment have changed greatly in recent decades.For example,annual sunshine hours and annual average wind speed decreased gradually,while the relative humidity increased slowly with time,which caused regional decrease of evaporation from water surface.Moreover,some plant diseases and insect pests are becoming more serious than ever owing to the changed meteorological factors,the development of irrigation system and the increased N application rate.Effective measurements for lessening the danger of plant diseases and insect pests are to establish water-saving agriculture and economic fertilization systems and to evolve new varieties with high pest resistance.