difficult to combine the maintenance of Training rangers for eco-hydrological work at biodiversity and groundwater extraction in Acknowledgements Theewaterskloof Dam in the Hottentots Holland Nature drought-sensitive areas. The fynbos biome Reserve. Photo: Deryck De Witt, SANBI. has a high proportion of endemic species, Project team: Jonathan Silvertown, David Gowing, therefore, a permanent lowering of the water Kevin McConway and Edward Youngs from the Open table, whether due to climate change or from University and Peter Linder from the University of abstraction, could lead to extinctions. Zurich, Switzerland, Guy Midgley of SANBI and Ernst Understanding how water resources Baard from CapeNature. What is being done? Project assistance: Deryck De Witt from SANBI and Els South Africa’s National Biodiversity Strategy Dorratt-Haaksma. shape our flora and Action Plan (NBSAP, 2005) identifies the Funding: Leverhulme Trust, UK for the pilot study Cape Floristic Region as a priority area and (2005-2007) and Darwin Initiative of the Department calls for research and monitoring programmes of Environment Food and Rural Affairs, UK (2007- Changes in ground water resources – either as a result of abstraction or climate change – to support integrated management of 2010). Hydrological monitoring in action. A ecosystems. A better understanding of the Co-operation: Site managers from SANParks and have important implications for fynbos ‘buzzing stick’ is used to monitor water pattern and processes of the Fynbos Biome, CapeNature. table depth. Photo: Deryck De Witt, including threatening processes, will enhance by Yoseph Araya, Open University, Milton-Keynes, England and Nick Walker, South African Biodiversity Institute (SANBI), Kirstenbosch SANBI. the way in which this biodiversity hotspot is Reading managed. A consortium of researchers from the Gowing, D., Lawson, C., Youngs, E. et al. 2002. The Open University of England and the South water regime requirements and the response to African National Biodiversity Institute (SANBI) hydrological change of grassland plant communities: at Kirstenbosch are working in co-operation DEFRA commissioned project BD1310, Final report with CapeNature and SANParks to establish to the Department for Environment, Food and Rural Within this plot on New Years Peak in the Limietberg Nature Reserve you can see species segregating along a network of sites on which hydrology and Affairs, Cranfield University, Silsoe. a ‘hydrological gradient’ from top to bottom. Visible vegetation bands include the restios Ceratocaryum botany will be monitored. This will help to Midgley, G.F., Ashwell, A., Rutherford, M. C., Bond, fimbriatum (1) and Elegia filacea (2), Erica fastigata (3) and Anthochortus crinalis (4). Photo: Mike Dodd. address the lack of suitable field data available W., Hannah, L., Powrie, L. 2002. Charting uncertainty: for analysis. The group has established ten sites Global climate change and its implications for our across the Western Cape. (See accompanying flora. Veld & Flora 88(2), 70-72. text box for a description of what is involved Midgley, G.F., Rutherford, M.C., Bond, W., Barnard, P. in monitoring). The work of the group will 2008. The heat is on… Impacts of climate change on ater is one of the most important balanced. Any change in water level that What about changing climate? also ensure future sustainability of monitoring plant diversity in South Africa. SANBI, Cape Town. resources for plants. It controls destabilizes the system is often serious. Species The uncharted waters of changing climate are by training local reserve personnel in ‘eco- Silvertown, J., Dodd, M.E., Gowing, D.J.G. and Wand influences their diversity response is either shifting from their local another impending threat for CFR. Climate hydrological’ techniques. Twenty-one rangers Mountford, J.O. 1999. Hydrologically defined niches and distribution. Water availability in soil range to more suitable habitat around them or comprises a complex relationship between from CapeNature and SANParks have been reveal a basis for species richness in plant communities. influences plants directly as a limiting resource, failing that disappearing from the particularly temperature, precipitation, evaporation, trained and are now monitoring the sites, and Nature 400, 61-63. or indirectly by filling soil pore spaces and locality. This change can happen at plot scale, wind and cloud. It is very likely that human further training is planned to include other Project website: www.open.ac.uk/fynbos reducing oxygen supply, which limits plant regionally and often within short time. activities through the increased emission of These modifications to the climate and the sites and conservation bodies to expand the root growth. Water regimes dictate different carbon dioxide and other greenhouse gases resulting change in soil water availability for project. GET CONNECTED vegetation types and ecosystems. Global The Cape Floristic Region will raise the surface temperature of the earth. plants will mean that the fynbos biome will be As the data is being processed, useful examples are the major world biomes, such The Cape Floristic Region (CFR) contains nearly A change in climate will have major impacts seriously affected by climate change over the information on the ecohydrological For more information on the project, contact Jonathan as tropical rainforest, deserts or tundra. At this 9 000 plant species, the majority of which on hydrological systems and will influence next 50-100 years. requirements of fynbos species and the Silvertown or Yoseph Araya, Department of Life level, precipitation differences as a result of are found nowhere else on Earth. One of the the hydrological cycle through increasing The demand for water in the Western Cape potential impact of environmental change Sciences, The Open University, Walton Hall, Milton, latitude and incoming solar radiation define most important habitats of the CFR is the surface temperatures and changing rates will increase over the next few decades, will come to light. This information will then Keynes, MK7 6AA, UK, email: [email protected] which species prevail. At a regional level, plant fynbos, most of which is currently protected of precipitation. An increase in surface air especially for municipal water supplies in be disseminated among nature-conservation or [email protected]. communities are determined by precipitation by a network of nature reserves managed temperature would increase plant transpiration rapidly urbanizing areas, for the production managers and other stakeholders, such as differences associated with topographic by CapeNature or the South African National and evaporation from both the soil and water of energy and for irrigation. Therefore, water water abstractors, involved in the management What does that mean? features such as elevation. Parks. The value of this hotspot of biodiversity bodies. The magnitude of any such increase will resource management will need to focus on of the unique fynbos habitat. Hopefully this More locally, within a small plot, species is recognized by the United Nations, which depend on changes in sunlight, humidity, wind demand management and the implementation knowledge will help not only in understanding Niche A niches is the range of environmental conditions distribution is often determined by the seasonal has awarded the region World Heritage status. speed, rainfall and vegetation characteristics. of regulatory controls to minimize stresses the current vegetation patterns and the in which a species can survive (fundamental niche) or variation in availability and behaviour of water. Conservation of such a global heritage calls We don’t know how individual catchment areas resulting from the increased demand. According likelihood of future changes, but it will also sustain itself even when competing with neighbouring Fine-scale differences in water regime results not only concerted local but also international will respond to changing precipitation patterns to a specialist group from the International help in the development of adaptive strategies species (realised niche). in a gradient of water stresses where different effort. and evapo-transpiration rates. However, it is Water Association, it will become increasingly for future scenarios. Fynbos ‘Fine bush’ in Afrikaans, this is the natural plants respond to varying levels of stress in Currently, rapid population growth and expected that drier areas will be more sensitive shrubland/heathland vegetation occurring mainly in different ways, and therefore their competitive economic development in the Western Cape to changes in climate. winter rainfall areas of the Western Cape. ability changes along this hydrological gradient. region are placing increasing demands upon According to future climate scenarios from Eco-hydrological monitoring techniques Eco-hydrology The science of the relationship of living The zone they occupy is known as their niche. water resources. Increased abstraction from most of the global climate models, the annual things and the water component (or hydrology) of It is where they can outcompete their rivals. the sandstone aquifers underlying important rainfall in the Western Cape is likely to decrease. Plots 50x50 m are set up with nine dipwell locations for hydrological monitoring. At the time of dipwell installation, soil their environment. This division into niches can be a particularly fynbos habitats is one of the options under The rate of re-charge of groundwater supplies samples are taken for characterization. The site is surveyed using a total station device for topography. At the same time Dipwell A buried PVC tube (about 1 m long) with important feature in species-rich ecosystems. consideration to meet the urban demand for will be greatly impacted by changes in surface 200 quadrats (1x1 m) are surveyed for the presence of species. Hydrological monitoring is conducted fortnightly for at least holes that let water enter and equilibrate with the (See accompanying photograph.) water. At present, little is known about how water availability and run-off. In the longer three years. Eco-hydrological monitoring involves the collection of data on the flow and soil storage of water at the site. surrounding soil. An array of dipwells are used to In a diverse community structured along such abstraction might affect the Cape flora term, this will also affect the re-charge of This enables us to understand the behaviour of water during the plants’ growth period. Two types of measurements are monitor water-table depth across a site over the a hydrological gradient, co-existing species’ and there is almost no information at all about aquifers. Changes in rainfall patterns (timing conducted. Firstly, the water-table depth and secondly, the amount of water stored in the soil. course of time. dependence on the soil-water regime is finely the eco-hydrology of Cape plants. and amount) will also influence water quality.

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