Biological studies of the effects of farm–forestry management of pasture∶earthworms

Abstract

Seasonal estimates of earthworm numbers and biomass were made by hand-sorting from samples taken between November 1975 and August 1976 from five sites, at Tikitere, near Rotorua, New Zealand. Four of these sites were sown pasture, planted with Pinus radiata D. Don. of a uniform age but at different densities. The fifth site was pasture without P. radiata. Measured environmental factors were generally similar for each of the five sites. Similar earthworm faunas were recovered from the five sites, with Allolobophora caliginosa (Savigny) dominant in each. Worm numbers were greatest in the pasture without P. radiata and, with one exception, generally decreased as planting densities increased. It is tentatively concluded that there is a relationship between worm numbers and density of planted P. radiata.

Keywords:

• earthworms
• Allolobophora caliginosa
• Lumbricus rubellus
• Octolasium cyaneum
• population dynamics
• farm–forestry
• Pinus radiata
• pastures
• Rotoiti loamy sand