BOTANICAL REJUVENATION OFFIELD MARGINS AND BENEFITS FORINVERTEBRATE FAUNA ON A DRYSTOCKFARM IN COUNTY LONGFORD

摘要

This study investigates methods to rejuvenate the flora of previously degraded field margins on apastoral farm in County Longford. We also assess the effects of individual treatments on the abundanceof various orders of invertebrates recorded within the experimental plots. Field margin treatmentswere 1.5m-wide unfenced control margins, 1.5m-wide fenced margins or 3.5m-wide fenced margins.Nutrient inputs were excluded from all of the experimental plots. The botanical composition of theplots was examined on four occasions between 2002 and 2004 using permanent, nested quadrats.Emergence traps were used to measure invertebrate abundance within treatment plots and the mainsward. Results indicated that 1) exclusion of nutrient inputs had a positive effect on plant speciesrichness within the field margins; 2) plant species richness decreased with increased distance fromthe hedgerow; 3) herb species richness was greatest in the 1.5m closest to the hedgerow; 4) greaterabundance of invertebrates occurred within the 3.5m-wide margins; 5) successful control of Pteridiumaquilinum was achieved through spot treatment with the selective herbicide 'Asulox'; and 6) a combin-ation of management techniques such as cutting and grazing is likely to enhance plant species richnessand facilitate the structural diversity of vegetation that is necessary for many invertebrate taxa.