Top dressing, adding soil and sand that trickle through grass and ground cover plants is not just necessary for proper drainage, but for plant and grass health.
追肥，增加土壤和沙，通过种草，地面覆盖植物涓滴不只是适当的排水必要的，但工厂和基层健康。
2
Before you plant, your soil should be tested for drainage and absorbance, and this will also help identify optimal ways to provide irrigation to the area.
植物之前，您应该测试土壤的排水和吸收，这也将有助于确定最佳方式，提供该地区的灌溉。
3
The drainage system in Qingxi Hydropower Plant originally adopted conventional relay control for its pump control system, which had many hidden troubles and resulted in multiple failures.