Soil health and carbon storage in community gardens in the Perth metropolitan area, Australia

Urban Farm DB summary

At six community gardens across three soil mapping units — calcareous deep sands, coloured sand and pale sands — in the Perth metropolitan area, Australia, soil samples were compared between cultivated raised beds and adjacent bare ground used as a control. Raised-bed soils showed lower bulk density, higher pH buffering capacity, more available nitrogen, phosphorus and potassium, greater cation exchange capacity, total carbon and microbial biomass than surrounding urban soil, and were estimated to have accumulated 0.55 kg of carbon per square meter (5.5 t/ha) in the top 10 cm, with no significant heavy metal contamination detected in any of the garden soils. The improved soil health and carbon storage were attributed mainly to regular application of compost produced within the gardens.