不同灌溉方式下林地土壤水分物理性质的初探

Preliminary Study on Different Irrigation Methods in Woodland of the Physical Properties of Soil Moisture

对兰州市北山不同灌溉方式下人工林地50cm土壤深度以内的土壤容重、孔隙度、持水量等指标做测定,探讨不同灌溉方式下林地土壤水分物理性质。结果表明:在喷灌地中土壤容重比无水灌溉地和大水漫灌均有所降低;土壤总孔隙度、毛管孔隙度比无水灌溉和大水漫灌均有所增加,非毛管孔隙度由于一些未知的原因没有呈现出预期的结果;土壤饱和持水量、毛管持水量、田间持水量均比无水灌溉和大水漫灌有所增加。喷灌能在一定条件下降低土壤容重,改善土壤孔隙状况,提高土壤的持水能力,从而改善了土壤水分的物理性质。而大水漫灌不但不能改善土壤水分的物理性质,还导致水的利用率降低。因此在林地灌溉中应首选喷灌方式。

Conclusions was drawn out through measurement of bulk density,porosity and water-holding capacity within 50 cm under the different irrigations for woodland land soil at north-mountain of Lanzhou.The results showed trat the soil bulk density decreased in sprinkle irrigated soil than that of non-irrigated and flood irrigated soil,but capillary porosity and total porosity of soil increased,accordingly soil saturated moisture capacity,capillary moisture capacity,and field moisture capacity was also increased,however,non-capillary porosity hadn＇t shown the desire results due to unknown reasons.This indicated that sprinkle irrigation can reduce soil bulk density to a certain extent,in addition to improves soil porosity conditions and soil moisture capacity,finally improves physical properties of soil moisture.Instead,the flood irrigation had not improved the physical properties of soil moisture,but also led to decreased utilization of the water.Therefore,sprinkle irrigation should be the preferred method in woodland.