Effect of introducing earthworms into horticultural land previously denuded of earthworms

摘要: Abstract An intensive vegetable growing area with no resident earthworms has received, since 1984, three cultivation treatments, involving varying degrees of disturbance, and two cropping regimes, a summer winter crop ryegrass cover crop. Five species Lumbricidae were introduced to part each treatment in 1986 assess the effect treatments on earthworm establishment survival, some soil characteristics. The experiment was designed so effects could be interpreted against background periodic changes characteristics caused by cultivation, weather. Earthworm population density (numbers m−2) activity (casts decreased increasing intensity cultivation. Cellulose decomposition rates increased up 30% presence earthworms, although per se had apparent effect. By contrast, substantially reduced strength (measured impact penetrometer) while introduction significant Similarly, saturated hydraulic conductivity topsoil situ) appeared unaffected earthworms. However, infiltration air-permeability measurements indicated that improved structure bulk matrix.