Thesis (MScConsEcol (Conservation Ecology and Entomology)--Stellenbosch University, 2008. / In the Cape Floristic Region of South Africa, where wine grape production and
biodiversity conservation are of major importance, innovative management of the
landscape is necessary to integrate the two activities. Alternative farming, such as organic
and biodynamic farming, focuses on the preservation of biological processes in
agroecosystems with the aim of increasing the sustainability of these sytems. It has been
demonstrated in other regions that alternative farming can enhance biodiversity. This
study assessed the potential of alternative vineyard management to conserve biodiversity,
in particular epigaeic arthropod diversity, relative to the more widespread integrated
vineyard management in the CFR. A hierarchical design was used, consisting of three
localities, with three land-uses nested within each locality. The land-uses were alternative
vineyards, integrated vineyards and natural vegetation sites as reference habitats.
Sampling was done in June and October 2006 using pitfall traps. Nested ANOVAs were
used to test for differences in abundance and species richness of the total assemblages,
functional feeding guilds and selected generalized predatory taxa. Assemblage patterns
were assessed using hierarchical agglomerative clustering and non-metric
multidimensional scaling. Canonical correspondence analyses were used to evaluate the
effects of environmental variables, management practices and landscape variables on
community composition. Alternative vineyards supported a significantly higher overall
arthropod abundance and species richness, more diverse predatory, saprophagous,
phytophagous and omnivorous guilds, as well as more abundant and speciose spider and
rove beetle assemblages than the integrated vineyards. Integrated vineyards harboured a
greater abundance of predators, whereas results for nectarivores, wood borers, parasitoids
and carabid beetles were variable. The differences could be explained in part by higher
non-crop vegetation complexity and reduced management intensity of the alternative
vineyards. Community composition was influenced by a combination of management
practices, the surrounding landscape and geographic locality, which highlighted the
interdependence of the cultivated land and its surroundings.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/1565 |
| Date | 12 1900 |
| Creators | Gaigher, Rene |
| Contributors | Samways, M. J., Stellenbosch University. Faculty of AgriSciences. Dept. of Conservation Ecology and Entomology. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Rights | Stellenbosch University |
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