Studies on the Relationships Between Earthworms and Soil Fertility

摘要: Observations on earthworm populations in the Carse of Stirling indicate that there are definite differences according to soil type both total population numbers and relative each species present. The light medium loams appear carry higher than heavier clay types or more open gravelly sand alluvial types. Within between respective soil-type populations, variable, but actual present a do not necessarily importance species. In all cases Allolobophora caliginosa is dominant species, being numerous loam elsewhere. A. longa subdominant forms substantial percentage clay. On high number, smaller because abundance caliginosa. also reduced soils—gravelly alluvium. This does differ very much from Lumbricus rubellus L. terrestris, as these two later soils loam. percentages similar within though lower other soils, number highest lowest There fair similarity open-textured percentages. Areas acid, natural pastures contain low variety. Some typical areas small active e.g. Dendrobaena rubida, D. octaedra Bimastus eiseni, which found well-established field populations. When agricultural treatment improves an area acid-pasture eventually decrease normally associated with good pasture land become established build up their