drainage material

基本解释

For apricots, use a soil-less potting compost over plenty of drainage material.
对于杏的栽培，需要大量的排水材料和少量的土壤构成的栽培条件。
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In general use a soil-based compost placed over a generous layer of drainage material such as earthenware crocks, pebbles or gravel.
通常在盆栽的底部铺上丰富的排水材料，像陶器碎片、沙砾等，然后在上面铺上土壤。
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The operational principles of UPVC spiral pipe and its specific characteristics in water passing capacity, drainage noise and material cost are introduced.
介绍UPVC螺旋管的工作原理，及其在通水能力、排水噪音、材料成本等方面的独特之处，是今后住宅排水系统中的发展方向。

Lakes also act as a sink for water and material inputs from diverse sources from their surrounding drainage basins.
UNESCO: Summary