| Chinese | English |
| 下层土 | subsoil Soil underlying surface soil, devoid of plant roots (土壤下层的土壤，缺乏植物根系。) |
| 含水土层 | aquifer Layers of rock, sand or gravel that can absorb water and allow it to flow. An aquifer acts as a groundwater reservoir when the underlying rock is impermeable. This may be tapped by wells for domestic, agricultural or industrial use. A serious environmental problem arises when the aquifer is contaminated by the seepage of sewage or toxins from waste dumps. If the groundwater in coastal areas is over-used salt water can seep into the aquifer (具有吸水及透水性的岩石、砂或砾石层。 当含水层下方岩层不透水时，含水层就成为地下水库，可以用水井抽水做为民生、农业或工业使用。 当含水层被污水或废弃物倾弃中有毒物质所污染时，将会造成严重的环境问题。 如果沿海岸的地下水被过度使用时，则会造成含盐的海水渗入含水层中。) |
| 土层 | soil layer Distinctive successive layers of soil produced by internal redistribution processes. Conventionally the layers have been divided into A, B and C horizons. The A horizon is the upper layer, containing humus and is leached and/or eluviated of many minerals. The B horizon forms a zone of deposition and is enriched with clay minerals and iron/aluminium oxides from the A layer. The C layer is the parent material for the present soil and may be partially weathered rock, transported glacial or alluvial material or an earlier soil (由内部的再分配过程所产生的独特的连续层土壤。传统的土壤层被分为A，B，C三层。A层是最上层，含有腐殖质，被浸出和/或多种矿物质淋溶。B层形成沉淀区，富含粘土矿物和来自A层的铁/铝氧化物。C层是当前土壤的母质，部分可能是风化岩，运输冰川或冲积土材料或者是更早的土壤。) |
