10.4 sustainable management of arid and semi arid environments

Question 1

sustainable management

Answer 1

• meets the needs of the present generation without compromising the ability of future generations to meet their own needs
• desertification costs an estimated $42 million each year

Question 2

CS: Game farming in the Eastern Cape province of South Africa

Answer 2

• Widespread poverty : overgrazing
• 95 per cent of this vegetation is under threat
• study: 41 game species was recorded on the 63 game farms surveyed
• trying to implement conservation measures
• recreational and trophy hunting
• foreign ecotourist and the hunting market: introduction of non-native species to the region
• Utilising game has provided an important secondary income to most mixed farmers
• Kudu and bushbuck, both indigenous to thicket
  vegetation, are among the most desired hunting species in the Eastern Cape

Question 3

CS: The establishment of drought-resistant fodder in the Eastern Cape

Answer 3

• Pastureland is especially fragile due to drought and overgrazing
• population pressure and, the absence of secure land-ownership policies
• During periods of prolonged drought, levels of cattle, sheep and goats decrease significantly
  -produce drought-resistant fodder crops such as the American aloe and indigenous gwanish
• aloe: It requires little moisture (annual rainfall in this region is around 450 mm).
• It is not attacked by any insects.
• Although low in protein, it raises milk production in cows.
• It can be used for soil conservation.
• After 10 years, it produces a pole that can be used for
  fencing or building.
• It can act as a windbreak.
• The juice of the aloe is used in the production of tequila.
• saltbrush requires less than half the water need by other crops

Question 4

CS:Essential oils in the Eastern Cape

Answer 4

• South African essential oils industry exports mainly to HICs in Europe (49 per cent), the USA (24 per cent)
• eucalyptus, citrus, geranium and buchu
• Globally, the essential oils industry – valued at around $10 billion
• Developing Essential Oil Industry would achieve much-needed agricultural and agri-processing diversification in the province
• 100 small commercial producers, of which less than 20 per cent are regular producers
• seasonal effects make southern hemisphere suppliers
  globally attractive
• strong trade links with Europe
• 10 government-sponsored trial sites currently in development
• labour-intensive industry
• Many plants are already known and used by local people as medicines
• Wild als (Artemesia afra) is an indigenous mountain shrub, used for the treatment of colds. Its oil has a strong medicinal fragrance and is used in deodorants and soaps. Moreover, it can stabilise many of the maize fields and slopes where soil erosion is a problem
  -For example, wild als, a mountain shrub is used for the treatment of colds and it can also stabilise maize fields and slopes where soil erosion in a problem.

Question 5

CS: Developing sustainable farming in Egypt

Answer 5

• 85 per cent of Nile’s water goes to agriculture
• 95 per cent of Egypt’s population lives in the Nile Valley and Delta: population pressure
• contains pollutants and pesticides from upstream countries and from Egypt itself: since 1950s, a million tonnes have been released into the environment
• Ethiopia is building the Grand Ethiopian Renaissance Dam on the Blue Nile, which is likely to cut supplies of fresh water to Egypt
• Aquaponics: enables farmers to increase yields by growing plants and farming fish in the same closed freshwater system
• Bustan is the first commercial aquaponics farm in Egypt.
• Water circulates from tanks containing fish through hydroponic trays that grow vegetables including cucumber, basil, lettuce, kale, peppers and tomatoes
• Each tank contains about a thousand tilapia fish: which are native to Egypt, resist slight water pH and temperature changes
• Water from the pond is then used to water the olive trees
  -This organic and closed system mimics natural processes and enables waste to be efficiently reused.
• The fish tanks provide 90 per cent of the nutrients plants need to grow
• ammonia from fish breathing is naturally transformed into nitrogen and absorbed by the plants before being sent back to the fish tanks, ammonia-free and healthy
• Bustan uses 90 per cent less water than traditional farming methods in Egypt and it produces 6–8 tonnes of fish per year, hydroponics can make lettuce grow 20 per cent faster than average
• Bustan is a labour-intensive farm and uses sustainable
  biological pest-control methods, such as ladybirds to kill aphids, in order to avoid chemical inputs
• plans to establish a permaculture system by introducing chickens that would feed on compost and produce natural fertilisers for the soil
• However, it is quite costly, especially for those on a low income : invested more than $43 500 to develop this scheme
• Vertical and rooftop farming, in light of the country’s serious water and food crisis, is also an effective way to grow organic food while cutting transportation costs, emissions and waste