基于RS和GIS技术的区域农田灌溉量预报研究及应用

区域尺度上开展农田灌溉量预报需要考虑土壤、作物和大气的空间差异性。论文针对农田灌溉现状分别建立了需水量灌溉预报模型和土壤湿润层灌溉预报模型,并在预报模型中引入RS和GIS技术来考虑预报参数的空间差异性,初步实现了区域尺度上250 m分辨率网格化的农田灌溉量预报,并在北京地区冬小麦灌溉量预报中进行了应用。结果表明:北京地区2010年冬小麦6月灌浆期间和11月下旬越冬前冻水的预报灌溉量分别为375 m³/hm²和600 m³/hm²,均较现行农业生产中建议的灌溉量明显偏少,具有节水经济效益潜力。这些结果显示了RS和GIS技术在区域尺度上农田灌溉预报中的良好应用潜力,且预报结论和应用效果能达到较好统一。

Research and Application of Regional Irrigation Amount Forecast for Cropland Based on RS and GIS

The spatial difference of soil,crop and atmosphere should be taken into account for cropland irrigation amount forecast in regional scale.To resolve the present agricultural production problems,water requirement irrigation forecast model and soil wetting layer irrigation forecast model were developed.Also,RS and GIS were introduced in the forecast models for the spatial variability of forecast parameters.Cropland irrigation forecast with a spatial resolution of 250 m over regional scale was initially implemented and it was applied in irrigation water forecast of winter wheat over Beijing area.The applied results showed that the forecast irrigation volume of grain-filling stage in June and frozen-water stage in late November in 2010 were 375 m3/hm2 and 600 m3/hm2,respectively.The irrigation amount of forecast was less than that recommended of current agricultural production,and there is the potential of water-saving economic benefits.These results indicated that RS and GIS had good application potential in cropland irrigation forecast over regional scale and the consistency between forecast and application effects.