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。

youdao

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

UNESCO: Summary