考虑农业大棚影响的农田排涝模数计算方法

Calculation Method of Drainage Coefficient of Farmland Considering Influence of A gricultural Greenhouse

农业大棚大面积使用导致地面不透水面积增加,使暴雨产生的径流量增大,影响农田作物的生长,最终导致农业圩区经济遭受破坏。为了提高圩区的排涝效率。减小暴雨的影响,在农业圩区排涝模数的计算中考虑大棚面积占比具有重要的现实意义。以江阴市南闸联圩为例,选取大棚面积占圩区旱地面积比分别为0%.5%、10%、15%、20%、25%、30%,并考虑圩区内典型作物水稻的不同生长周期耐淹能力,采用平均排除法计算分析了农业圩区的排涝模数。结果表明,大棚面积占比对农田排涝系数的计算影响较大,每增加5%的大棚面积占比,排涝模数增大1.69%~1.94%;水稻返青期受暴雨的影响最大,因此现代化农业圩区排涝模.数计算时,必须考虑作物耐淹能力和大棚面积占比等因素。

The widely used agricultural greenhouse leads to the increase of impervious area,and increase of runoff caused by rainstorm,which affects the growth of agricultural crops and finally results in the economic damage of agricul-tural polder area.In order to improve the drainage efficiency of polder area and reduce the impact of rainstorm,it is of great practical significance to consider the proportion of greenhouse area in the calculation of drainage modulus of agricul-tural polder area.Taking Nanzha united polder in Jiangyin City as an example.the ratio of greenhouse area to polder area is chosen 0%,5%,10%,15%,20%,25%and 30%,and the flood tolerance of rice in different growth periods in the polder area is considered.The average drainage method is used to calculate the drainage modulus of agricultural polder ar-ea.The results show that the ratio of greenhouse area to farmland drainage coefficient has a great impact,and the drain-age modulus increases by 1.69%-1.94%for every 5%increase in the ratio of greenhouse area to farmland drainage coeffi-cient.In addition,the rice returning to green period is most affected by rainstorm.Therefore,it is necessary to consider such factors as crop flood tolerance and the ratio of greenhouse area when calculating the drainage modulus of modern ag-ricultural polder area.