Ársrit Ræktunarfélags Norðurlands - 01.01.1973, Side 58

2. In unfertilized plots the number of animals was approximately the
same as in those receiving inorganic NPK fertilizers.
3. l’lots receiving phosphorus and potassium only, showed a consid-
erably greater number of animals than those receiving inorganic
NPK fertilizers.
4. Cultivated pastures, that have been receiving cows manure for
seven years (Exp. no. 136—63) showed, by far, the most abundant
fauna, irrespective of species of animals.
HEIMILDARRIT
Brauns, A. 1968: Praktische Bodenbiologie. Gustav Fischer Verlag.
Burns, N. C., 1971: Soil pH elfects on nematode populations associated soy-
beans. Journal o£ Nematology 3, 238—245. Soil and Fertilizers, 1972 35:1,
abstr. 424.
Cernova, N. M., Byzova, Yu. Cernova, A. /., 1971: Relationship of
number, biomass and gaseous exchange rate indices in micro-arthropods in
substrates with various organic matter contents. Pedobiologia, 11, 306—314.
Soil and Fertilizers. 1972, 35:1, abstr. 429.
Helgi Hallgrimsson 1969: Lífið í jarðveginum. Ársrit Rf. Nl. 2, 31—68.
Nyhan, J. W., Frederick, L. R., Norton, D. C. 1972: Ecology of nematodes
in Clarion-VVebster toposequences associated with Glycine max (L) Merril.
Soil and Fertilizers, 1972, 35:4, abstr. 3217.
Oostenbrink, M. 1971: Comparison of techniques for populaticm estimation
of soil and plant nematodes. (Jr bókinni: Methods of study in Quantitative
Soil Ecology: population, production and energy flow. Edited by J. Phillipson,
72-82.
Veðráttan 1970.
Weis-Fogh, T., 1917—18: Ecological Investigations on Mites and Collem-
boles in the soil. Natura Jutlandica, 1, 135—270.
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