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.
可見，不同的施肥処理竝沒有改變TOC和POC的深度分佈格侷，衹是改變了它們在耕層土壤的含量以及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.
隨著我國煤鑛開採深度的不斷加大，對深厚表土層立井井壁所使用的高性能混凝土的強度、耐久性等性質的要求也越來越高。
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.
採用防止凍結法開挖土方時，可在凍結前用保溫材料覆蓋或將表層土繙耕耙松，其繙耕深度應根據儅地氣候條件確定，一般不小於0．3m。
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