3.5 Drivers of ecosystem change
3.5.2 Direct drivers of change
3.5.2.2 Overexploitation
Overexploitation or unsustainable harvesting is one of the drivers of change of ecosystems and biodiversity, which affects all ecosystems; be it aquatic, forest, or grassland (Secretariat of the CBD, 2010). It is said that over-fishing is a cause for concern in marine ecosystems while unsustainable hunting for food, ornaments and medicines is a major concern for terrestrial ecosystems (Duraiappah et al., 2005; Pereira et al., 2012). Overexploitation is perpetuated by government and multinational companies and, individuals from poor communities relying on the natural environment for their livelihoods (Secretariat of the CBD, 2010; Meyfroidt et al., 2013). The Secretariat of the CBD (2010) states that it is for this reason that management systems have been developed and are still being developed to manage ecosystems in such a way that they support poor adjacent communities.
Ecosystems play an important role in developing economies throughout the world. It is through natural resource exploitation that goods and services are produced for domestic and commercial consumption (UNEP, 2007; Secretariat of the CBD, 2010). However, the natural resources become overexploited when the rate of extraction or use exceeds the ability of ecosystems to regenerate and/or
recuperate. Nepstad et al. (2006) assert that the world contributes to overexploitation of natural resources through the demands placed on natural products such as timber, agriculture produce, medicinal plants and animal products. Currently, many African countries are faced with increasing poaching of wildlife for their horns, an act which is mainly induced by increasing international demand for trophy horns (Miliken and Shaw, 2012). Poaching of the rhino is threatening the white rhino with an annual loss rate at 532 in South Africa (Miliken and Shaw, 2012:11). Rhino poaching exemplifies how international demand for ecosystem services in collaboration with local populations seeking livelihoods can lead to loss of species. This is the case with plant species in South Africa, especially in the Cape Floristic Region and KwaZulu-Natal coastal belt of South Africa, where overexploitation of species is rampant (DEAT, 2006; Privett et al., 2014).
The demand for water supplies has increased threefold since the 1960s while the supply thereof remains constant causing uncertainty over sustainability of fresh water use for future generations (2030 Water Resources Group 2009; United Nations Educational, Scientific and Cultural Organization, 2009). According to Masondo (2011), it was projected at the South African Water and Energy Forum held in Johannesburg South Africa that fresh water shortages would be felt as early as 2020 in South Africa. The looming water shortages in South Africa are mainly a result of increasing need which outstrips the ability to meet the needs (Masondo, 2011). The wetlands in Johannesburg have been purifying the region’s water from mine and industrial pollutants (SANBI, 2013), however, it has come to light that the untreated acid mine water threatens the country’s ability to provide clean water for human consumption (Gass, 2012). With pressures exerted on water sources, in addition to ongoing pollution, there is need to conserve and manage ecosystems that maintain clean water supplies (SANBI, 2013).
Biodiversity loss due to deforestation estimated to be 13 million hectares per year with South America and Africa being the most affected (Johnson et al., 2013: 237). This is a major cause for concern globally and the major instigators are increasing demand for land to produce more food, timber and settlement (Lambin and Meyfroidt, 2011). Deforestation and habitat transformation pose a threat to habitats (which can lead to loss and extinction of many valuable plant species such as medicinal plants) and the traditions and culture of African societies which are intricately reliant on the natural environment (Okigbo et al., 2008). In addition, Johnson et al. (2013) assert that the consequences of high rates of biodiversity loss on human well-being remain unknown. Nevertheless, the threat posed by deforestation calls for conservation of ecosystems through effective land-use planning and/ or zoning (Lambin and Meyfroidt, 2011).
Medicinal Plants
Medicinal plants are a socio-cultural heritage of Africa and have been used for hundreds of years in rural areas and later in urban areas as a source of primary health-care (Herndon et al., 2009; Towns et al., 2014). Semenya and Maroyi (2012) assert that medicinal plants provide the needed medicines in rural areas mainly administered by traditional healers, especially where health facilities are absent. To some people, medicinal plants provide first aid treatment while to others, it is the only health-care that they receive; for instance, in Ghana, more than half the child population suffering from malaria are treated with traditional medicines extracted from medicinal plants (Secretariat of the CBD, 2010). The medicinal industry in some of the African countries is said to be highly profitable and is estimated to be worth US$ 64 000 in Sierra Leone and US$ 7.8 million in Ghana (Van Andel et al., 2012: 368;
Jusu and Sanchez, 2013: 299). According to Driver et al. (2012: 14), about 2 000 plant species are used for medicinal purposes 82 of which are threatened of extinction in South Africa. Approximately 72% of the population in South Africa depends on traditional medicines (commonly known as muthi) for their primary health-care (Williams et al., 2013: 23).
Over the years, developed countries have created a demand for herbal and traditional medicines and thus the emergence of pharmaceuticals developing herbal-based medicines and other products (Okigbo et al., 2008). Singh et al. (2013) state that this resulted from the awakening and awareness of the potential harm conventional medicines can cause to the general human well-being. However, due to the high demand for medicinal plants, so much pressure has been exerted on the ecosystems such that most of the ecosystems are disintegrating (Lambert et al., 2005; SANBI, 2013).
Medicinal plants are used for subsistent as well as commercial consumption (Kar and Jacobson, 2012;
Vashist and Sharma, 2013). Van Andel et al. (2012: 368) assert that “medicinal plant markets not only provide a snapshot of a country’s medicinal flora, they also reflect local health concerns and the importance of traditional medicine among its inhabitants.” Medicinal plants support livelihoods of poor rural communities (Hicks et al., 2014), for instance in South Africa, medicinal plants have been credited for their economic role in society especially that of providing healthcare to both urban and rural inhabitants (Williams et al., 2013). According to SANBI (2013: 46), in 2007 the harvesting and trade of medicinal plants was valued at R2.9 billion. Another estimate of the medicinal plants industry is placed at R1 million per day and this value excludes dispensing fees (Phipson, 2012: 19). As a result, there is increasing pressure on medicinal plant stocks through over-harvesting which can be attributed to increased demand for herbal medicines resulting in increase in prices (Phipson, 2012). In addition, the high demand for herbal medicines has exerted a lot of pressure on the indigenous plant species due to overexploitation of wild populations, hence the need to use these resources sustainably (Okigbo et al., 2008; Phipson, 2012). For instance, SANBI (2013: 46) estimates that 10% of the
traded medicinal plant species are threatened and this calls for urgent attention to achieve sustainability.
Hassan (2012) asserts that medicinal plants are important as they play a role in development of cultural traditions globally. In addition, medicinal plants are important as they contribute towards rehabilitation of degraded land through improving fertility of soils and control of erosion (Lambert et al., 2005). Furthermore, medicinal plants contribute towards the diversity of ecosystems.
Consequently, conservation of medicinal plants is critical to maintaining genetic and species diversity, cultural and traditional knowledge through research and documentation (Okigbo et al., 2008; SANBI, 2013). Okigbo et al. (2008) and Jain et al. (2012) suggest that there are various medicinal plant conservation strategies and they include practices that promote conservation within natural habitats and outside their natural habitats. A management strategy for conserving medicinal plants outside their natural habitats is known as ‘conservation through cultivation’ or ex-situ conservation (Okigbo et al., 2008; Jain et al., 2012). Jain et al. (2012) assert that ‘conservation through cultivation’ is used to safeguard and propagate species that are threatened in their natural habitats. More effective ecosystem management practices are needed especially those which consider the community needs for medicinal plants and those of conserving biodiversity. This study seeks to identify practices utilised in the GGEP in ecosystem management, which includes management of medicinal plants.