ISSN:
1365-2494
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Abstract Seasonal cutting treatments were imposed on abandoned perennial ryegrass/white clover swards at three sites in the UK to determine the impact on species diversity and the contribution of different species to biomass. Before the cutting experiment, the abandoned swards had received no fertilizer applications and had been neither grazed nor cut for 3 years. The original sown species, Lolium perenne and Trifolium repens, had virtually disappeared during this period. Self-sown grasses, including Agrostis capillaris, Dactylis glomerata, Festuca rubra, Holcus mollis, Poa pratensis and P. trivialis, had become dominant at two sites. Ranunculus repens was the dominant species at the third site, and self-sown grasses, such as Holcus lanatus and P. trivialis, and Juncus and Carex species were also present. The standing herbage in 2·5 m × 2·5 m subplots was cut to 2·5 cm above ground level and removed annually in either June or October for 7 years at two sites and 6 years at the third site. Total biomass removed was generally 〈 4 t dry matter (DM) ha−1, and both total and live biomass decreased over time in the June cutting treatment at two sites. There were large changes in species composition after initiating the two cutting treatments. The numbers of grass and dicot species increased, although many new species had a low frequency of occurrence. The contribution of species to biomass changed over time, with species showing a vegetative regenerative strategy decreasing over time at one site. At this site, annual cutting in June was slightly more effective than cutting in October in reducing the dominance of R. repens; cutting in early October effectively reduced Juncus spp. At two sites, there was a decrease in the contribution of the species group showing seasonal regeneration by seed, and differences between cutting dates for two species within this group at one site. L. perenne and T. repens remained at much lower levels than in adjacent unfertilized, grazed swards. Reseeding may be necessary to create species assemblages for ecological and agricultural objectives.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1365-2494.2003.00350.x
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