topsoil depth

基本解释

Thus, the different fertilization practices tended to(affect) not the depth distribution of TOC and POC but the content and proportion of POC in topsoil.
可见，不同的施肥处理并没有改变TOC和POC的深度分布格局，只是改变了它们在耕层土壤的含量以及POC的分配比例。
With the increasing depth of coal mining in China, there is an immediate need to improve the strength and durability of high performance concrete used in deep topsoil mine shafts.
随着我国煤矿开采深度的不断加大，对深厚表土层立井井壁所使用的高性能混凝土的强度、耐久性等性质的要求也越来越高。
On prevent-freezing earthwork excavation method, cover insulation material before freezing or loosen topsoil with tillage depth determined by local climatic conditions, generally not less than 0.3m.
采用防止冻结法开挖土方时，可在冻结前用保温材料覆盖或将表层土翻耕耙松，其翻耕深度应根据当地气候条件确定，一般不小于0．3m。
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