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Mapping Grazing-Induced Degradation in a Semi-Arid Environment: A Rapid and Cost Effective Approach for Assessment and Monitoring

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Abstract

Improved techniques for measuring and monitoring the state of biodiversity are required for reporting on national obligations to international and regional conservation institutions. Measuring the extent of grazing-related degradation in semi-arid ecosystems has proved difficult. Here we present an accurate and cost-effective method for doing this, and apply it in a South African semi-arid region that forms part of a globally significant biodiversity hotspot. We grouped structurally and functionally similar vegetation units, which were expert-mapped at the 1:50,000 scale, into four habitat types, and developed habitat-specific degradation models. We quantified degradation into three categories, using differences between dry and wet season values of the Normalized Difference Vegetation Index (NDVI) for the three succulent karoo habitats, and the difference between maximum and mean NDVI values for the subtropical thicket habitat. Field evaluation revealed an accuracy of 86%. Overall, degradation was high: 24% of the study area was modeled as severely degraded, and only 9% as intact. Levels of degradation were highest for bottomland habitats that were most exposed to grazing impacts. In sharp contrast to our methods, a widely used, broad-scale and snapshot assessment of land cover in South Africa was only 33% accurate, and it considerably underestimated the extent of severely degraded habitat in the study area. While our approach requires a multidisciplinary team, and in particular expert knowledge on the characteristics and spatial delimitation of vegetation types, it is repeatable, rapid, and relatively inexpensive. Consequently, it holds great promise for monitoring and evaluation programs in semi-arid ecosystems, in Africa, and beyond.

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References

  • Agami M, Eshel A, Waisel Y (1998) Plant recolonization after severe degradation: a case study in the Negev highlands of Israel. Journal of Arid Environments 38:411–419

    Article  Google Scholar 

  • Aronson J, Milton SJ, Blignaut J (2007) Restoring natural capital. Science, business and practice. Island Press, Washington DC

    Google Scholar 

  • Ashwell A, Sandwith T, Barnett M, Parker A, Fumanekile W (2006) Fynbos fynmense: people making biodiversity work. South African National Biodiversity Institute, Pretoria, 288 pp

  • Asner GP, Heidebrecht KB (2005) Desertification alters regional ecosystem–climate interactions. Global Change Biology 11:182–194

    Article  Google Scholar 

  • Balmford A, Cowling RM (2006) Fusion or failure. The future of conservation biology. Conservation Biology 20:692–695

    Article  Google Scholar 

  • Balmford A, Bennun L, ten Brink B, Cooper D, Côté IM (2005a) Science and the convention on biological diversity’s 2010 target. Science 307:212–213

    Article  CAS  Google Scholar 

  • Balmford A, Crane P, Dobson A, Green RE, Mace GM (2005b) The 2010 challenge: data availability, information needs and extraterrestrial insights. Philosophical Transactions of the Royal Society Series B 360:221–228

    Article  Google Scholar 

  • Beinart W (ed) (2003) The rise of conservation in South Africa. Settlers, livestock and the environment 1770–1950. Oxford University Press, Oxford, 425 pp

  • Beukes P, Cowling RM (2003) An evaluation of some restoration techniques for the Succulent Karoo, South Africa. Restoration Ecology 11:308–316

    Article  Google Scholar 

  • Bonora D (2006) Historical changes in the environment and land use practices of the Little Karoo since 1900. BSc (Honours) thesis, University of Cape Town, Cape Town, 45 pp

  • Burgess ND, D’Amico Hales J, Ricketts TH, Dinerstein E (2006) Factoring species, non-species values and threats into biodiversity prioritisation across the ecoregions of Africa and its islands. Biological Conservation 127:383–401

    Article  Google Scholar 

  • Cowling RM, Esler KJ, Midgley GF, Honig MA (1994) Plant functional diversity, species diversity and climate in arid and semi-arid southern Africa. Journal of Arid Environments 27:141–158

    Article  Google Scholar 

  • Cowling RM, Pressey RL, Rouget M, Lombard AT (2003) A conservation plan for a global biodiversity hotspot—the Cape Floristic Region, South Africa. Biological Conservation 112:191–216

    Article  Google Scholar 

  • Crossman ND, Bryan BA (2006) Systematic landscape restoration using integer programming. Biological Conservation 128:369–383

    Article  Google Scholar 

  • Cupido CF (2005) Assessment of veld utilization practices and veld condition in the Little Karoo. MSc thesis, University of Cape Town, Cape Town, 175 pp

  • Desmet PG, Cowling RM (1999) In: Dean WRJ, Milton SJ (eds) Climate—an ecological perspective. Cambridge University Press, Cambridge, pp 3–16

  • Dregne HE (2002) Land degradation in the drylands. Arid Land Research and Management 16:99–132

    Article  Google Scholar 

  • Esler KJ, Cowling RM (1995) The comparison of selected life-history characteristics of Mesembryanthema species occurring on and off mima-like mounds (heuweltjies) in semi-arid southern Africa. Vegetatio 116:41–50

    Google Scholar 

  • Esler KJ, Milton SJ, Dean WRJ (2006) Karoo Veld. Ecology and management. Briza Publications, Pretoria

    Google Scholar 

  • European Council (EC) (2001) 2001 Presidency conclusions, Goteborg Council, 15 and 16. SN/200/1/01 REV1. p 8

  • Fairbanks DHK, Thompson MW, Vink DE, Newby TS, van der Berg HM, Everard DA (2000) The South African land cover characteristics database: a synopsis of the landscape. South African Journal of Science 96:69–82

    Google Scholar 

  • Fox SJ, Hoffman MT, Hoare D (2005) The phenological pattern of vegetation in Namaqualand, South Africa and its climate correlates using NOAA-AVHRR data. South African Geographical Journal 87:85–94

    Google Scholar 

  • Fuller RM, Groom GB, Mugisha S, Ipulet P, Pomeroy D, Katende A, Bailey R, Ogutu-Ohwayo R (1998) The integration of field survey and remote sensing for biodiversity assessment: a case study in the tropical forests and wetlands of Sango Bay, Uganda. Biological Conservation 86:379–391

    Article  Google Scholar 

  • Groves C (2003) Drafting a conservation blueprint. A practitioner’s guide to planning for biodiversity. Island Press, Washington

    Google Scholar 

  • Hein L, de Ridder N (2006) Desertification in the Sahel: a reinterpretation. Global Change Biology 12:751–758

    Article  Google Scholar 

  • Hoare DB, Frost P (2004) Phenological classification of natural vegetation in southern Africa using AVHRR vegetation index data. Applied Vegetation Science 7:19–28

    Google Scholar 

  • Hoffman MT, Ashwell A (2001) Nature divided. Land degradation in South Africa. University of Cape Town Press, Cape Town

    Google Scholar 

  • Hoffman MT, Cousins B, Meyer T, Petersen A, Hendricks H (1999) Historical and contemporary land use and the desertification of the Karoo. In: Dean WRJ, Milton SJ (eds) Ecological patterns and processes. Cambridge University Press, Cambridge, pp 257–273

    Google Scholar 

  • Hoffman MT, Dean WRJ, Allsopp N (2003) Landuse effects on plant and insect diversity in Namaqualand. In: Allsopp N, Palmer AR, Milton SJ, Kirkman KP, Kerley GIH, Hurt CR, Brown CJ (eds) Proceedings of the VIIth international rangelands congress held in Durban, South Africa, 26th July–1st August 2003, pp 166–176

  • Jenkins M, Green RE, Madden J (2003) The challenge of measuring global change in wild nature: are things getting better or worse? Conservation Biology 17:20–23

    Article  Google Scholar 

  • Kammerud TA (1996) Soil impact on satellite based vegetation monitoring in Sahelian Mali. Geografiska Annaler Series A—Physical Geography 78A(4):247–259

    Article  Google Scholar 

  • Kerr JT, Ostrovsky M (2003) From space to species: ecological applications for remote sensing. Trends in Ecology and Evolution 18:299–305

    Article  Google Scholar 

  • King LC (ed) (1942) South African scenery. Oliver & Boyd, Edinburgh

    Google Scholar 

  • Knight AT, Driver A, Cowling RM et al (2006) Designing systematic conservation assessments that promote effective implementation: best practice from South Africa. Conservation Biology 20:739–750

    Article  Google Scholar 

  • Lechmere-Oertel RG, Kerley GIH, Cowling RM (2005a) Patterns and implications of transformation in semi-arid succulent thicket, South Africa. Journal of Arid Environments 62:459–474

    Article  Google Scholar 

  • Lechmere-Oertel RG, Cowling RM, Kerley GIH (2005b) Landscape dysfunction and reduced spatial heterogeneity in soil resources and fertility in semi-arid succulent thicket, South Africa. Austral Ecology 30:615–624

    Article  Google Scholar 

  • Lloyd JW, van den Berg EC, Palmer AR (2002) Patterns of transformation and degradation in the thicket biome, South Africa. Unpublished report, TERU, Port Elizabeth

  • Lovegrove BG, Siegfried WR (1989) Spacing and origin(s) of Mima-like earth mounds in the western Cape Province of South Africa. South African Journal of Science 85:108–112

    Google Scholar 

  • Low AB, Rebelo AG (1996) Vegetation of South Africa, Lesotho and Swaziland. Department of Environmental Affairs & Tourism, Pretoria

    Google Scholar 

  • Mace G, Masundire H, Baillie J et al (2005) Biodiversity. In: Millennium ecosystem assessment, 2005. Current state and trends: findings of the condition and trends working group. Ecosystems and human well-being, vol 1. Island Press, Washington DC

  • Mills AJ, Cowling RM (2006) Rate of carbon sequestration at two thicket restoration sites in the Eastern Cape, South Africa. Restoration Ecology 14:38–49

    Article  Google Scholar 

  • Mills AJ, Cowling RM, Fey MV, Kerley GIH, Donaldson JS, Lechmere-Oertel RG, Sigwela RG, Skowno AL, Rundel P (2005) Effects of goat pastoralism on ecosystem carbon storage in semi-arid thicket, Eastern Cape, South Africa. Austral Ecology 30:807–813

    Google Scholar 

  • Milton SJ, Gourlay ID, Dean WRJ (1997) Shrub growth and demography in arid Karoo, South Africa. Inference from wood rings. Journal of Arid Environments 37:487–496

    Article  Google Scholar 

  • Mittermeier RA, Hoffmann M, Pilgrim JD, Brooks TB, Mittermeier CG, Lamoreux JL, da Fonseca G (2005) Hotspots revisited: earth’s biologically richest and most endangered ecoregions. Cemex, Mexico City

    Google Scholar 

  • Pickup G, Chewings VH (1994) A grazing gradient approach to land degradation assessment in arid areas from remotely-sensed data. International Journal of Remote Sensing 15:597–617

    Article  Google Scholar 

  • Pierce SM, Cowling RM, Knight AT, Lombard AT, Rouget M, Wolf T (2005) Systematic conservation planning products for land-use planning: interpretation for implementation. Biological Conservation 125:441–458

    Article  Google Scholar 

  • Pressey RL (1999) Applications of irreplaceability analysis to planning and management problems. Parks 9:42–51

    Google Scholar 

  • Pressey RL, Cowling RM, Rouget M (2003) Formulation of conservation targets for biodiversity pattern and process in the Cape Floristic Region, South Africa. Biological Conservation 112:99–127

    Article  Google Scholar 

  • Prince SD (2001) Spatial and temporal scales for detection of desertification. In: Reynolds JF, Stafford Smith DM (eds) Global desertification—do humans cause deserts? Dahlem University Press, Berlin, pp 23–40

    Google Scholar 

  • Qi J, Chehbouni A, Huete AR, Kerr YH, Sorooshian S (1994) A modified soil adjusted vegetation index. Remote Sensing of Environment 48:119–126

    Article  Google Scholar 

  • Reyers B, Rouget M, Jonas Z, Cowling RM, Driver A, Desmet PG (2007) Developing products for conservation decision-making: lessons from a spatial biodiversity assessment for South Africa. Diversity and Distributions 13:608–619

    Article  Google Scholar 

  • Rouget M, Richardson DM, Cowling RM, Lloyd JW, Lombard AT (2003) Current patterns of habitat transformation and future threats to biodiversity in terrestrial ecosystems of the Cape Floristic Region. Biological Conservation 112:63–85

    Article  Google Scholar 

  • Rouget M, Cowling RM, Vlok J, Thompson M, Balmford A (2006) Biodiversity intactedness is seriously compromised by current indices. Global Change Biology 12:2032–2036

    Article  Google Scholar 

  • Scholes RJ, Biggs R (2005) A biodiversity intactness index. Nature 434:45–49

    Article  CAS  Google Scholar 

  • Smith AB (1999) Hunters and herders in the Karoo landscape. In: Dean WRJ, Milton SJ (eds) The Karoo: ecological patterns and processes. Cambridge University Press, Cambridge, pp 243–256

    Google Scholar 

  • Thompson M, Vlok J, Cowling RM, Cundill SL, Mundau N (2005) A land transformation map for the Little Karoo. GeoterraImage, Pretoria

    Google Scholar 

  • Ting IP, Hanscom Z (1977) Induction of acid metabolism in Portulacaria afra. Plant Physiology 59:511–514

    Article  CAS  Google Scholar 

  • Todd SW, Hoffman MT (1999) A fence-line contrast reveals effects of heavy grazing on plant species diversity and community composition in Namaqualand, South Africa. Plant Ecology 142:169–178

    Article  Google Scholar 

  • Tucker CJ, Dregne HE, Newcomb WW (1991) Expansion and contraction of the Sahara Desert. Science 253:299–301

    Article  Google Scholar 

  • Turner MD (2003) Methodological reflections on the use of remote sensing and geographic information science in human ecological research. Human Ecology 31:255–279

    Article  Google Scholar 

  • United Nations Environment Programme (UNEP) (2002) Report on the sixth meeting of the conference of the parties to the convention on biological diversity (UNEP/CBD/COP/6/20/Part 2) strategic plan decision VI/26. Convention on Biological Diversity

  • van der Heyden F, Stock WD (1996) Regrowth of a semiarid shrub following simulated browsing: the role of reserve carbon. Functional Ecology 10:647–653

    Article  Google Scholar 

  • Vlok JH, Cowling RM, Wolf T (2005) A vegetation map for the Little Karoo. Succulent Karoo Ecosystem Planning Project, South African National Biodiversity Institute, Kirstenbosch

  • Wessels KJ, Prince SD, Frost PE, van Zyl D (2004) Assessing the effects of human-induced land degradation in the former homelands of northern South Africa with a 1 km AVHRR NDVI time-series. Remote Sensing of Environment 91:47–67

    Article  Google Scholar 

  • Wessels KJ, Prince SD, Malherbe J, Small J, Frost PE, Van Zyl D (2007) Can human-induced land degradation be distinguished from the effects of rainfall variability? Journal of Arid Environments 68:271–297

    Article  Google Scholar 

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Acknowledgments

MT, JV and RMC thank the Critical Ecosystem Partnership Fund for funding, and RMC thanks the National Research Foundation (Pretoria) and the Nelson Mandela Metropolitan University for support.

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Authors and Affiliations

  1. GeoTerraImage, P.O. Box 295, Persequor TechnoPark, Pretoria, 0020, South Africa

    Mark Thompson

  2. Department of Botany, Nelson Mandela Metropolitan University, P.O. Box 77000, Port Elizabeth, 6031, South Africa

    Jan Vlok & R. M. Cowling

  3. Biodiversity Center, South African National Botanical Institute, Brumeria, Pretoria, 0001, South Africa

    Mathieu Rouget

  4. Conservation Science Group, Department of Zoology, University of Cambridge, Cambridge, CB2 3EJ, UK

    Mathieu Rouget & Andrew Balmford

  5. Leslie Hill Institute for Plant Conservation, Department of Botany, University of Cape Town, Private Bag X3, Rondebosch, 7701, South Africa

    M. T. Hoffman

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  1. Mark Thompson
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  2. Jan Vlok
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  3. Mathieu Rouget
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  4. M. T. Hoffman
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  6. R. M. Cowling
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Correspondence to Mathieu Rouget.

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Thompson, M., Vlok, J., Rouget, M. et al. Mapping Grazing-Induced Degradation in a Semi-Arid Environment: A Rapid and Cost Effective Approach for Assessment and Monitoring. Environmental Management 43, 585–596 (2009). https://doi.org/10.1007/s00267-008-9228-x

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  • DOI: https://doi.org/10.1007/s00267-008-9228-x

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