The key factors causing soil dried layers are great thickness and depth of membrane water zone under ground as well as small thickness of gravitywater zone.
由降水少量决定的、埋藏深度小而厚度大的薄膜水带的存在是引起土壤干层发育的直接作用的因素。
2
Some areas in China are abundant in resources, but short of water source nearby, so the pressured gravitywater transportation in long distance must be adopted.
我国一些地区资源丰富，但就近水源缺乏，不得不采用长距离有压重力输水。
3
The stepped low-pressurized water diversion system is a new type of gravitywater supply system, which is simple in structure and water conservation weir is the pivotal structure.