Biodiversity and the ecosystem approach in agriculture, forestry and fisheries. Proceedings
The Eastern Cape province of South Africa is home to a large human population that is rural, poor and has experienced little development. The major pressures on these communal rangelands are from intense herbivory, wood fuel harvesting and shifting cultivation. Eight study sites in communal and commercial farming systems were selected and a number of diversity indices were performed on floristic data from these sites. It was found that mean species richness, total number of species and species evenness were higher in the commercial than communal grasslands although the variation in species composition (internal heterogeneity) was similar. Analysis using plant functional traits indicated that there was a shift in the communal areas towards pioneer woody species that had little browsing, fuel or timber value, grass species with lower palatability and forb species that were tolerant of intense herbivory and disturbance to the soil surface. There were more exotic species per sample in the communal than commercial grasslands and these contributed a higher proportion of the total vegetation cover. Landcover data indicates a loss of woody vegetation cover and transformation by shifting cultivation. Production data from livestock numbers at a district level indicate no reduction in long-term stocking rates, but stock composition has changed. Data from stocking rates is problematic as a measure of production and must be considered to be inconclusive since other factors could maintain high stock numbers. There is evidence of improving rangeland condition in the area around towns, where animal biomass is also lower than was historically recorded.
| Main Authors: | , |
|---|---|
| Format: | Texto biblioteca |
| Language: | |
| Published: |
Rome (Italy) FAO
2003
|
| Subjects: | Biodiversity, Agroecosystems, Farming systems, Genetic resources, Resource conservation, Forestry, Aquatic environment, Agropastoral systems, Agropisciculture, Organic agriculture, Soil biology, Case studies, MILIEU AQUATIQUE, SYSTEME AGROPASTORAL, AGROPISCICULTURE, AGRICULTURE BIOLOGIQUE, BIOLOGIE DU SOL, ETUDE DE CAS, BIODIVERSITE, AGROECOSYSTEME, SYSTEME D'EXPLOITATION AGRICOLE, RESSOURCE GENETIQUE, CONSERVATION DES RESSOURCES, FORESTERIE, AMBIENTE ACUATICO, SISTEMAS AGROPASCICOLAS, AGROPISCICULTURA, AGRICULTURA ORGANICA, BIOLOGIA DEL SUELO, ESTUDIOS DE CASOS PRACTICOS, BIODIVERSIDAD, AGROECOSISTEMAS, SISTEMAS DE EXPLOTACION, RECURSOS GENETICOS, CONSERVACION DE LOS RECURSOS, CIENCIAS FORESTALES, |
| Online Access: | http://www.fao.org/3/y4586e/y4586e00.htm |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|