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Pollination services under different grazing intensities

Published online by Cambridge University Press:  28 February 2007

Carolin Mayer
Carolin Mayer*
Affiliation:
University of Hamburg, Biocentre Klein Flottbek and Botanical Garden, Ohnhorststr. 18, 22609, Hamburg, Germany
*
*Email: [email protected]
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Abstract

A study was conducted to investigate whether a lack of pollinators, pollination and therefore, a shortage of fruit set of perennial plants is more likely to occur in overgrazed land than farmland without grazing pressure, as this could have considerable effects on the reproduction of certain plant species. The study was conducted at two adjacent BIOTA biodiversity observatories (<url>www.biota-africa.org</url>) in Namaqualand, South Africa. Individuals of certain plant species of the family of Aizoaceae were measured and flower and fruit production recorded. Malaise traps and transect walks were used to document insect diversity. Preliminary results indicate that not all plant species show reduced flower production but that fruit set is indeed compromised on overgrazed land. Insect diversity and abundance is partially reduced under heavy grazing pressure, especially in locations where the vegetation cover is low and dominated by unpalatable plant species.

Keywords

pollinatorsbiodiversityplant reproductionovergrazingarid rangelandsSucculent Karoo
Type
Research Article
Information
International Journal of Tropical Insect Science , Volume 24 , Issue 1 , March 2004 , pp. 95 - 103
Copyright
Copyright © ICIPE 2004

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References

Allsopp, N. (1999) Effects of grazing and cultivation on soil patterns and processes in the Paulshoek area of Namaqualand. Plant Ecol. 142, 179–187.CrossRefGoogle Scholar
Bittrich, V., Hartmann, H. E.K. (1988) The Aizoaceae—a new approach. Bot. J. Linn. Soc. 97, 239–254.CrossRefGoogle Scholar
Brown, B. J., Mitchell, R. J. (2001) Competition for pollination: effects of pollen of an invasive plant on seed set of a native congener. Oecologia 129, 43–49.CrossRefGoogle ScholarPubMed
Chittka, L., Schürkens, S. (2001) Successful invasion of a floral market. Nature 411, 653CrossRefGoogle ScholarPubMed
Cowling, R. M., Hilton-Taylor, C. (1994) Patterns of plant diversity and endemism in southern Africa: an overview. Strelitzia 1, 31–52.Google Scholar
Cowling, R. M., Hilton-Taylor, C. (1999) pp. 42–56. In The Karoo—Ecological patterns and processes (Edited by Dean, W. J. D. and Milton, S. J.). Cambridge University Press, Cambridge.CrossRefGoogle Scholar
Dafni, A. (1992) Pollination Ecology—A Practical Approach. Oxford University Press, Oxford/New York/Tokyo.Google Scholar
Davis, S. D., Heywood, V. H. (1994) Centres of plant diversity: a guide and strategy for their conservation 1. Oxford Oxford University Press, Oxford, 354 pp.Google Scholar
Esler, K. J. (1999) In The karoo—Ecological patterns and processes. pp. 123–144 (Edited by Dean, W. R. J. and Milton, S. J.).Cambridge University Press, Cambridge.CrossRefGoogle Scholar
Gess, F. W., Gess, S. K. (1993) Effects of increasing land utilization on species representation and diversity of aculeate wasps and bees in the semi-arid areas of southern Africa. pp. 83–113 In Hymenoptera and Biodiversity. (Edited by LaSalle, J. and Gauld, I. D.). CAB International, Wallingford, UKGoogle Scholar
Hoffman, M. T., Cousins, B., Meyer, T., Petersen, A., Hendriks, H. (1999) pp. 257–273. In The Karoo. Ecological patterns and processes (Edited by Dean, W. R. J. and Milton, S. J.). Cambridge University Press, Cambridge.CrossRefGoogle Scholar
Jürgens, N. (1991) A new approach to the Namib region—I. Phytogeographic subdivision. Vegetatio 97, 21–38.CrossRefGoogle Scholar
Kearns, C., A, Inouye, D., W. (1997) Pollinators, flowering plants, and conservation biology. BioScience 47, 297–307.CrossRefGoogle Scholar
Kearns, C. A., Inouye, D. W., Waser, N. M. (1998) Endangered mutualisms: The conservation of plant–pollinator interactions. Annu. Rev. Ecol. Syst. 29, 83–112.CrossRefGoogle Scholar
Kevan, P. G. (1991) Pollination: keystone process in sustainable global productivity. Acta Hortic. 288, 103–110.CrossRefGoogle Scholar
McIntyre, N. E., Hostetler, M. E. (2001) Effects of urban land use on pollinator (Hymenoptera: Apoidea) communities in a desert metropolis. Basic Appl. Ecol. 2, 209–218.Google Scholar
Milton, S. J., Dean, W. R. J. (1990) Seed production in rangelands of the southern Karoo. S. Afr. J. Sci. 86, 231–233.Google Scholar
Milton, S. J., Yeaton, R. I., Dean, W. R. J. and Vlok, J. H. J. (1997) In Vegetation of Southern Africa. (Edited by Cowling, R. M. and Richardson, D. M. and Pierce, S. M.). Cambridge University Press, Cambridge.Google Scholar
Palmer, A. R., Hoffman, M. T. (1997) pp. 167–188. In Vegetation of Southern Africa (Edited by Cowling, R. M., Richardson, D. M. and Pierce, S. M.). Cambridge University Press, Cambridge.Google Scholar
Proctor, M., Yeo, P., Lack, A. (1996) The Natural History of Pollination Harper Collins Publishers (The New Naturalist), London.Google Scholar
Rathcke, B. J. and Jules, E. S. (1993) Habitat fragmentation and plant–pollinator interactions. Curr. Sci. 65, 273–278.Google Scholar
Rutherford, M. C., Westfall, R. H. (1986) Biomes of Southern Africa—An objective categorization. Mem. Bot. Surv. S. Afr. 54, 1–98.Google Scholar
Seymour, C. L., Dean, W. R. J. (1999) Effects of heavy grazing on invertebrate assemblages in the Succulent Karoo, South Africa. J. Arid. Environ. 43, 267–286.CrossRefGoogle Scholar
Struck, M. (1992) Pollination ecology in the arid winter rainfall region of southern Africa: A case study. Mitt. Inst. Allg. Bot. Hamburg 24, 61–90.Google Scholar
Struck, M. (1994a) A check-list of flower visiting insects and their host plants of the Goegab Nature Reserve, Northwestern Cape, South Africa. Bontebok 9, 11–21.Google Scholar
Struck, M. (1994b) Flowers and their insect visitors in the arid winter rainfall region of southern Africa: observations on permanent plots. Insect visitation behaviour. J. Arid. Environ. 28, 51–74.CrossRefGoogle Scholar
Struck, M. (1995) Land of blooming pebbles: flowers and their pollinators in the Knersvlakte. Aloe 3z and 4, 56–64.Google Scholar
Todd, S. W., Hoffman, M. T. (1999) A fence-line contrast reveals effects of heavy grazing on plant diversity and community composition in Namaqualand, South Africa. Plant Ecol. 142, 169–178.CrossRefGoogle Scholar
Withgott, J. (1999) Pollination migrates to top of conservation agenda. BioScience 49, 857–862.CrossRefGoogle Scholar