Slide1 : Coastal Lagoons & Beaches
e.g. Walvis Bay, Sandwich Harbour and Lüderitz wetlands
Sheltered marine areas (lagoons) or beaches provide a haven for breeding and feeding coastal species
Typically high in biodiversity and attract numerous bird species – in places up to 300,000 individuals and 40-50 species What are wetlands?
Wetlands are areas where there is permanent or temporary surface water. Wetlands include perennial and ephemeral rivers, floodplains, pans, lakes, dams, springs, swamps, marshes, seeps, oshanas, estuaries and shallow seas and islands.
Wetlands are aquatic or semi-aquatic ecosystems, each supporting its own aquatic, semi-aquatic and riparian plant and animal communities.
Wetlands are among the world’s most biologically productive ecosystems and are rich in biodiversity.
There are many types of wetlands found throughout Namibia, although many of them may be dry for months or years, such as ephemeral rivers, pans and floodplains.
Almost 5% of Namibia’s surface area is covered by various types of wetlands, although the majority are dry most of the time. Erosion prevention – Vegetation in and adjacent to wetlands and rivers slows water flow, holds soils and prevents erosion.
Aquifer recharge – Water from wetlands recharges adjacent underground aquifers.
Improvement of water quality – Wetland ecosystems maintain good water quality in several ways such as filtering pollutants and breaking down dead and decaying material.
Climatic stability – Wetland vegetation can act as a carbon reservoir and assists in reducing the amount of carbon dioxide in the atmosphere, decreasing the greenhouse effect and leading to a more stable climate.
Linear oases – Both perennial and ephemeral rivers that pass through otherwise arid areas are sources of water and support linear strips of vegetation, enabling people and wildlife to survive there. Why are wetlands important?
Wetlands provide both goods and services. They provide a variety of renewable natural resources as well as vitally important ecological services. Natural Resources:
Water – Water maintains all life processes in the environment and is necessary for human health and to maintain agricultural, industrial and other activities.
Vegetation – Wetland and riverine vegetation have multiple uses, such as food (fruit), medicines, building materials, etc.
Animals – Animals such as marine and freshwater fish, frogs, reptiles, birds and many aquatic invertebrates are found in wetlands, while other wildlife congregates around wetland areas.
Floodplains – Rivers carry sediment or silt which are rich in nutrients. These nutrients provide the basis for aquatic and adjacent terrestrial food webs.
Ecological Services:
Flood attenuation – Wetland vegetation regulates stream and river flow, helping to control floods. Perennial Rivers
e.g. Kunene, Okavango, Zambezi, Orange Rivers and Kwando-Linyanti-Chobe System
Flow throughout the year, carrying large volumes of water
Are only found along Namibia’s northern and southern borders; all originate in neighbouring countries
Economics of Wetlands
Most people take wetlands and wetland-services for granted and do not realize the economic value of wetlands. If these natural resources were degraded, Namibian livelihoods would be affected and people would have fewer resources available to them. If the ecological services provided by wetlands were reduced, they would need to be replaced with artificial alternatives which are extremely expensive.
Tourism is an important economic incentive for the conservation and management of wetlands is tourism. With conservation, these areas can attract tourists and provide economic benefits for local communities and for Namibia. This poster was commissioned by the Namibia Nature Foundation and designed and compiled by Danica Shaw, Eco-Logic Environmental Management Consulting CC (061) 235460 Sponsors Protection of wetlands
A comprehensive Wetlands Policy for Namibia has been developed which aims to integrate sustainable wetland management, protection and conservation into decision making at all levels.
Current legislation and policies that are important to wetland management include: The Water Act 1954, The National Water Policy 2000, the National Agricultural Policy 1995, the Water Supply and Sanitation Policy 1993, The Water Corporation Act 1997, and Vision 2030.
Namibia is a signatory to the Ramsar Convention which is the Convention on Wetlands of International Importance. The Convention recognises the economic, ecological, cultural, scientific and recreational importance of wetlands and advocates wise-use.
Four wetlands in Namibia are currently designated as “wetlands of international importance,” or Ramsar sites:
* Walvis Bay Lagoon * Orange River Mouth
* Sandwich Harbour Lagoon * Etosha Pan What are the pressures on Namibia’s wetlands?
Over-exploitation of wetland resources due to human population growth and poverty
Poor integrated planning and inadequate sectoral cooperation
Increasing demand for water
Over-abstraction of groundwater
Pollution from domestic, agricultural and industrial sources
Physical alterations to natural water courses (dams, reservoirs, etc.)
Alien and invasive species
Urban, coastal and hydropower developments
Erosion caused by deforestation and overgrazing
Climate change What can be done to reduce these pressures?
Promote integrated land-use management and planning, involving different sectors as well as the broad participation of all stakeholders
Promote integrated water resource management
Create incentives and support regulations which ensure the conservation and sustainable use of wetland resources
Increase the conservation of wetland ecosystems and biodiversity
Prevent water pollution in wetlands, their catchments and groundwater sources
Strengthen monitoring, legislative frameworks and institutional capacity
Continue and promote research and environmental assessment of wetland areas
Control development in or immediately surrounding wetlands
Control alien species and prevent further introduction Ephemeral Rivers
e.g. Hoanib, Huab, Ugab, Swakop, Kuiseb, Fish, and Nossob Rivers
Flow after good rains, usually for a few days to a few weeks only, and sometimes not for several years
Most originate within Namibia – the majority of Namibia’s rivers are ephemeral
Serve as ‘linear oases’ – provide underground water and maintain dense riparian vegetation that is used by humans, livestock and wildlife in arid areas
Floodplains
e.g. areas alongside the Okavango and Zambezi Rivers and the Kwando-Linyanti-Chobe System
Typically low-lying areas next to rivers where water overflows in times of seasonal flooding
Support diverse populations of mammals, birds, fish, reptiles, invertebrates, plants and people.
Oshanas
e.g. the Cuvelai drainage area
Complex delta network of interlinked shallow channels and pans in north-central Namibia which receives both local seasonal rain and inflow from Angola
Provide fish and other food resources when in flood, and recharges the water table in the cuvelai regions
Pans
e.g. Etosha Pan, Nyae-Nyae Pan, Sossousvlei and Kalahari pannetjiesveld
Shallow ephemeral pools, often salt-lined, fed by local rainfall or ephemeral rivers
Sinkhole Lakes
e.g. Otjikoto and Guinas Lakes, Aigamas Cave, and Dragon’s Breath
Deep, permanently filled caverns formed when the roof of an underground cave collapses (Namibia has some of the largest underground lakes in the world!)
Support unique endemic invertebrates and fish
Swamps/Marshes
e.g. Linyanti swamp, confluence of Cuito and Okavango Rivers
Well vegetated areas with permanently water-logged soils
Found alongside perennial rivers, at confluence of rivers or in coastal areas (salt marsh)
Typically high in biodiversity
Vleis
e.g. Tsumkwe vleis (Makuri Pan), rainwater pools in Caprivi and Otjozondjupa regions
Shallow well-vegetated pools fed by local rainfall or groundwater seepage – can be either seasonal or permanent
Springs/Seeps
e.g. Sesfontein, Karstveld, Damaraland, Naukluft, Ai-Ais and Gross Barmen springs
Permanently vegetated pools or streams formed by artesian water or by groundwater raising to the surface
Geothermal springs are biologically harsh environments, but are popular tourist attractions Estuaries
e.g. Kunene River mouth, Orange River mouth
Areas at the mouths of perennial rivers
Experience river and tidal flows – alternation of freshwater and saline water
Sensitive and highly productive ecosystems
Dams/Impoundments
e.g. Hardap, von Bach, and Olushandja Dams
Artificial bodies of water created by damming the flow of river water
Built for human use – water storage, supply to urban areas, agriculture, hydroelectric power (not yet in Namibia), recreation, etc.
Constructed Wetlands
e.g. Evaporation ponds at sewage works or abattoirs, artificial ponds, and canals
Artificial discharge areas for waste water treatment
In some cases, they are specially designed to partially purify waste water for alternative uses
Water transfer canals, such as Eastern National Water Carrier Explanation of Terms:
aquatic: relating to water
aquifer: layers of permeable material such as sand, surrounded by non-permeable rock, which hold water. Aquifers are sources of groundwater.
biodiversity: the variety of life on all levels. Biodiversity includes genetic variation within a species, the diversity of species and the variety of communities and ecosystems.
ecosystem: the combination of all the living and non-living factors which make up an environment and its organisms
ephemeral: flowing only for a short time after good rains
geothermal: relating to heat from the interior of the Earth
greenhouse effect: the warming of the Earth as a result of the release of gases, mostly from burning fossil fuels
perennial: flowing throughout the year
riparian: relating to a river bank
semi-aquatic: relating to the area between aquatic and terrestrial zones
terrestrial: relating to dry land