地下铺膜对温室芹菜种植土壤深层渗漏的影响

为了探讨温室蔬菜种植过程中不同地下铺膜方式对深层渗漏的影响,选择芹菜作为试验样本,在试验区域布置了不同间隔宽度的平面条带和U型条带共四个试验组以及一个不铺膜的对照组,进行试验研究。试验时采用PR1分层水分探头和烘干法监测土壤水分变化过程,根据实测根层土壤水分含量确定各试区的灌水时间,在温室大棚内设置自动气象站收集环境气象数据,利用能量平衡法计算芹菜生育期的腾发量,最终通过水量平衡方程计算各种铺膜方式下的深层渗漏,分析地下铺膜对深层渗漏的影响。在各种地下铺膜方式下,芹菜均长势良好,并且都取得了不同程度的减少深层渗漏的效果,其中U型铺膜减小深层渗漏的效果好于平面铺膜,而相同铺膜方式下间隔越小效果越好。铺膜后,灌水间隔时间有所加长,大部分方案的总灌水量和灌水次数均有所降低,在最理想的情况下深层渗漏降低了50%。研究结果表明,温室大棚蔬菜种植,采用地下铺膜的方法可以有效降低深层渗漏,节约灌溉用水,但在不同条件下优化的布置参数仍需通过进一步的试验或数值分析才能得到。

Effects of Ground Film on Deep Percolation of Planting Soil for Cultivating Celery in Greenhouse

In order to investigate the effects of different ground film forms on the deep percolation of cultivating vegetable in greenhouse, celery was chosen as the experimental sample, and four experimental groups with different ground film forms in the horizontal strip and U-shaped strip with different interval widths were designed in the study area and another group without ground film was also conducted for comparison. The variation process of soil moisture was measured by the PR1 layered moisture probe combining with the oven drying method. The time for irrigation was determined based on the observation data of soil moisture in the root layer. The automatic meteorological station was set up in the greenhouse to collect the meteorological data. The evapotranspiration of celery during the growth period was calculated using the energy balance method. The deep percolation for each type of ground film was calculated using the water balance equation, which can be used to determine the impacts of different ground film forms on the deep percolation. The results showed that under all types of ground film, the celery grows well and the deep percolation is reduced to some extent. The ground film in the U-shaped strip has better effects on reducing deep percolation that that in the horizontal strip and the effect of reducing deep percolation is better for the same ground film form with smaller interval widths. After the ground film, the time interval between irrigations increases, the total amount of irrigation and the frequency of irrigation reduce for most cases, and the deep percolation reduces by 50% under the ideal situation. Consequently, the deep percolation can be reduced and irrigation water can be saved using the ground film when cultivating vegetable in greenhouse, but the optimal configuration parameters under various conditions need further experimental or numerical analysis.