부산대학교 도서관

(l) The effect of cutting calcareous grassland on its invertebrate fauna were examined in an experiment on Arhenatherum-dominated grassland. Four treatments, cutting in May, in July, in both May and July and control (untreated) were applied annually to four radomized blocks of plots, each of which was sampled regularly with a vacuum insect, Adult Hemiptera (Heteroptera and Auchenorhyncha) were identified to species and the effects of cutting on their numbers, abundance and diversity determined. (2) Simpson’s and BrtHouln’s indices of species-diversity we preferred, for statistics and practical reasons, and to maintain continuity with previous work. Simpson’s index proved to be rather insensitive to changes brought about by cutting (3) Cutting in May slightly reduced the abundance and diversity of Heteroptera and the effects were short-lived. The effects on the abundance and species-richness of Auchenorhyncha were more marked and more persistent but diversity was scarcely reduced. Abundance, richness and diversity of both groups were consistently reduced Abundance, richness and diversity of both groups were consistently reduced by cutting in July. The effects on Heteroptera persisted until about January but those on Auchenorhyncha until shortly before the May cut. There was little difference between the effects of cutting in both May and July only, and generally the treatments group themselves into the two pairs May + Control and July + Both. (4) The results show that cutting in May only can maintain a high richness and diversity of Hemiptera on areas of grassland, including nature reserves, where reserves where management is necessary or imposed. Rolational management by cutting is advocateas a system of managing grassland nature reserves and is easier to establish than rotational grazing. [ABSTRACT FROM AUTHOR]