Aquest Link no existeix en el seu idioma, Veure en: English (en),
O utilitzar Google Translate:  

amanziforfood.co.za/portfolio-ite...lity-trenches/

Trench beds are 1m wide and 2m long. They are dug to 1m deep then packed with dry grass/leaves, compost, manure and soil. Used in food-gardens. They make (create) highly fertile soils which can absorb and store water. Provide an immediately usable planting bed even on shallow or poor soils. Often used with diversion furrows and mulching. Trench beds can be connected to diversion furrows, which collect water from adjacent areas and direct it to the trenches.