秸杆条带状覆盖条件下土壤水分运动的实验研究及数值计算

本文在开展了一系列室内外试验研究基础上，建立了有效根量密度分布函数，得到了较为切合实际的二维根系吸水率模型.同时通过田间不同条件下水面蒸发试验资料分析，得到了条带状覆盖时棵间无麦秸覆盖地和棵间麦秸覆盖地水面蒸发量(各布设20cm蒸发皿所观测的值)与大气水面蒸发量(试验场气象站位置布设的20cm蒸发皿观测值)之间的关系式.通过农田作物生理指标观测，得到了作物叶面积指数与水面蒸发量之间的关系.从而更合理地处理了条带状覆盖下上边界条件.并以此为基础，建立相应的数学模型，进行了数值模拟，实测值与计算值吻合较好，表明所建立的数学模型是可靠的，数值分析是可行的。

The experimental studies of soil water movement mathematical model under the condition of partial mulching

Based on the theoretical analysis and numerical computation, a two dimensional root uptake model which is more suitable for practical use was obtained. At the same time, by analyzing the experimental data, relationships between bare soil evaporation, evaporation from mulch strips and atmosphere evaporation were derived. By observing the physiology index of crop in the field, the relationship between leaf area index (LAI) and water surface evaporation were also obtained. The upper boundaries in the corn field can be classified into four categories: bare soil with shelter from crops, bare soil without shelter from crops, mulch with shelter from crops and mulch without shelter from crops. The corresponding mathematical model was presented. The effectiveness of the method presented was tested by soil moisture data obtained from field. The results indicate that the values of computation agree with the experimental data fairly well.