Land Degradation & Agriculture in South Africa

Project Deadlines and Guidelines

• All projects are due on 7 APRIL 2025.
• Use Calibri or Arial font, size 11, with 1.5 spacing and justified alignment.
• Ensure all sources are credible and properly referenced.
• All work must be original and use APA referencing style to avoid plagiarism.
• Your responses must include a clear structure, including an introduction, main content, and conclusion.
• Submit the final document as a PDF or Word file.

Projects

• Choose one of the following 3 projects.

Project 1: Land Degradation on Agriculture in South Africa

• You are required to analyse the impact of land degradation which includes water erosion, chemical deterioration, wind erosion, and physical deterioration on agricultural productivity in a specific South African province or farming region.

• Land degradation is a significant environmental challenge in South Africa.

• Land degradation affects food security, livelihoods, and economic sustainability.

• Steps include identifying causes of land degradation, investigating its impacts on crop yields, food security, and communities, examining rehabilitation and conservation efforts, and proposing solutions.

Project 2: Biodiversity Loss and Climate Change in South Africa

• Climate change is accelerating biodiversity loss in South Africa.

• Explore how climate change impacts biodiversity in a selected South African ecosystem.

• It is necessary to select an ecosystem in South Africa (e.g., Fynbos, Succulent Karoo, Drakensberg, Grasslands), identify threatened species and their roles, analyse climate change factors, and investigate conservation efforts.

• Deliverables will be a research paper with findings and recommendations.

• Biodiversity ensures maintenance of ecological balance and providing services such as food, water, and air purification.

Project 3: Sustainable Land Use Plan for a Rural Community

• Design a sustainable land use plan that addresses environmental challenges while promoting socio-economic benefits.

• Many rural communities in South Africa struggle with balancing development and environmental conservation.

• Choose a rural community as well as its issues such as deforestation, soil erosion, or water scarcity.

• You will assess environmental and socio-economic challenges, propose a land use strategy with sustainable practices, and consider implementation feasibility involving policy support and community engagement.

• The final product should be a detailed report with maps, strategies, and justifications.

Topic Areas

• Key areas will cover freshwater, the hydrological cycle, the water crisis, and water's relation to society
• Water Scarcity
• Water Conservation
• Climate change and its effect on water resources
• Transboundary water cooperation in management of water
• International waters
• The concept of water privatization

What is freshwater

• Freshwater contains minimal dissolved salts, differentiating it from seawater or brackish water.
• Freshwater originates from precipitation of atmospheric water vapor.
• Freshwater is found in inland lakes, rivers, and groundwater bodies, or from melting snow or ice.
• Freshwater can naturally exist as a solid, liquid, or gas.
• As temperatures rise in lakes, oceans, rivers, and streams, liquid water transforms into gas, forming clouds of moisture.

Water availability

• Water available to living organisms is very limited.
• Saltwater/Oceans makes up 97.5% of the water.
• Fresh water makes up 2.5% of the water.
• Of the fresh water Icecaps and glaciers make up 79%.
• Groundwater accounts for 20%.
• Freshwater habitats cover less than 1% of the world's surface area, housing about 10% of all known animals and up to 40% of fish species.
• Freshwater is a limited resource.

The water cycle

• Water exists in lakes, oceans, swamps, soil, living creatures, and plants.
• Described as the continuous movement of water on, above and below the Earth's surface.
• The water cycle is also known as the hydrologic cycle or the hydrological cycle or a continuous big circle.
• The main stages include evaporation, condensation, precipitation, and runoff.

Important stages of the water cycle

• Key stages covered will be evaporation, condensation, precipitation, and runoff.

Evaporation

• The process in which water from oceans, lakes, rivers, and other bodies of water is heated by the sun and converted into water vapor.
• When heated by the sun, exertion, or artificial means, water molecules become excited and spread out causing the loss of density called evaporation.
• The evaporation sees the water rise into the air forming clouds of water vapor.
• Plants transpire by releasing water vapor from their leaves into the atmosphere.
• Temperature, humidity, and wind conditions all factor into affecting the amount of evaporation that can occur.

Condensation

• Water vapor rises into the atmosphere, cools, and turns back into liquid water droplets, forming clouds.
• Cloud formation is essential for precipitation.
• Water vapor cools upon contacting the cooler air high in the sky.
• This occurs because cooler temperatures slow down water molecules and cluster them together.
• The vapor turns into clouds moved by air currents and winds.
• The water vapor condenses as water if it cools to above zero degrees centigrade.

Precipitation

• Water droplets in clouds become too heavy and precipitate back to the Earth's surface.
• This can take different forms, including rain, snow, sleet, or hail, depending on temperature and atmospheric conditions.
• Precipitation is a key part of the water cycle as it replenishes water in rivers, lakes, and groundwater sources.
• Some of the fallen rain evaporates, and some is absorbed into the ground through infiltration.
• Water infiltrates the soil, moves in all directions, and either seeps into nearby streams or sinks deeper into groundwater storage, also called aquifers.
• When an aquifer becomes too full, it starts leaking onto the surface, forming a spring.
• If the water is near a volcano or thermal energy, it can form a hot spring.

Runoff

• After rainfall and saturation, or snowmelt, water follows gravity down hills, mountains, or inclines to form or join rivers.
• This process called runoff, is how water rests in lakes and returns to the ocean.
• Waterfalls depend on the incline of where water is falling.
• When several threads of water meet, they form a stream.
• Streamflow marks the direction of water movement an dis central to the concept of currents.
• Streams and rivers run off to form lakes or rejoin the ocean according to their proximity.
• They also help shape landscapes through erosion and transport nutrients to various ecosystems.
• Water continually moves in a cycle with no beginning or end.
• The water remains mostly level due to the balance of water always in the process of replenishment from other sources.

Water needs

• The average adult's body weight is made up of 60% water.
• The heart is composed of 73% water.
• The brain and lungs are composed of 80% water.

Homes

• Showers account for 29% of home water usage
• Kitchens account for 16%.
• Laundry accounts for15%.
• Bathroom taps account for 12%.
• Flushing toilets accounts for 17%
• Basins accounts for 7%
• Other uses account for 4%.

Agricultural use

• 40% of the world's food supply is produced via irrigation.
• 70% of the world's fresh water is used to produce food.
• During the last century, global water use rose more than twice the rate of population growth

Industrial use

• 2,700 Liters of Water are needed To Make One Cotton Shirt.
• This is enough drinking water for that one person for 2.5 years.

Water usage in South Africa

• Agriculture is the primary usage at 62%.
• Domestic use
• Power generation
• Mining and Industrial
• Other

The global water crisis

• 2.1 billion people lack access to safe drinking water.
• 844 million lack access to even basic drinking water services.
• 263 million people spend over 30 minutes per trip collecting water from sources outside the home.
• 159 million people drink untreated water from surface water sources.
• SDG 6 is the Sustainable Development Goal to Ensure Access to Water and Sanitation for All

Water pollution

• Categorized as either point sources or non-point sources.

Point sources

• Point sources have pollution originating from known sources at identified points.
• This makes pollution easy to identify, monitor, and regulate, as with discharges from urban wastewater treatment, industry and fish farms etc.
• River basins are polluted by: biochemical oxygen demand (BOD) from sewage and discharges from agro-based and manufacturing industries
• River basins are polluted by ammoniacal nitrogen (NH3-N) from sewage.
• River basins are polluted by suspended solids (SS) from earthworks and land-clearing activities.

Non-point sources

• Cannot be traced to a single point of discharge, making it difficult to locate, monitor, and control
• They are from discharges from sources such as vehicle emissions, construction sites, urban runoff, and forestry etc
• Sediment from improperly managed construction sites, crop and forest lands, and eroding stream banks
• Non-point sources also include bacteria and nutrients from livestock, pet wastes and sewage systems.
• Excess fertilizers, herbicides and insecticides from agricultural lands and residential areas contribute to non-point source pollution.
• So do oil, grease and toxic chemicals from urban runoff.

Water quality

• Water quality's physical, chemical, biological, and aesthetic characteristics determine its fitness for various uses and for protecting the health and integrity of aquatic ecosystems.

Water quality depends on

• Local geology and ecosystem
• Human uses such as sewage dispersion
• Industrial pollution
• Overuse
• Use of water bodies as a heat sink.

Water Quality Indicators

• Indicators can be any of: Physical Parameters, Chemical Parameters, or Biological Parameters

Physical parameters

• Physical parameters define the characteristics of water that respond to the senses of sight, touch, taste, or smell.
• The most commonly considered physical characteristics include suspended solids, temperature, taste, odour, colour, and turbidity.

Physical parameters unpacked

• Suspended solids are measured in mg/L.
• Inorganic compounds such as clay, silt, and sand are sources of the solids.
• Other sources are organic compounds such as fine organic matter, human waste.
• Suspended solids affect the aesthetic (turbidity and transparency), human health, and create adsorption points/centres for chemicals and micro-organisms.
• Turbidity measures compounds such as clay, sand, plant fibre, and human waste in Nephelometric Turbidity Units (NTU) or Formazin Units (FU).
• Odour and taste come from inorganic compounds such as minerals, metals, and salts which give water taste but no odor.
• Organic compounds from petroleum and/or degradation of organic matters also contribute to odour and taste.
• Temperature is measured in °C or °F and is affected by ambience as well as industrial activities such as cooling systems.
• Temperature change can disturb biological activities like micro-organisms and aquatic life.
• Temperature change can also change chemical properties such as the degree of gas solubility, density and viscosity.
• Dissolved oxygen levels: As water temperature increases, the solubility of oxygen decreases.
• Chemical processes: Temperature affects the solubility and reaction rates of chemicals.
• Chemical reactions proceed more rapidly at higher temperatures.
• Biological processes: Temperature affects metabolism, growth, and reproduction.
• Species composition of the aquatic ecosystem: Aquatic species' survival is limited to temperature ranges.
• Water density and stratification: Density is highest at 4ºC; temperature differences affect stratification and turnover.
• Environmental cues for life-history stages: Temperature affects insect emergence and fish spawning.

Chemical parameters

• The chemical characteristics of water are numerous with metals like manganese (Mn), zinc (Zn), and copper (Cu), being essential to biochemical processes.
• Every substance that dissolves in water can be called a chemical water quality characteristic.
• Chemical parameters include total dissolved solids (TDS), alkalinity, hardness, metals, organic compounds, and nutrients.
• Total Dissolved Solids (TDS) are from inorganic compounds such minerals, metal and gases that causes taste, colour and odour problems, affect one's health and, in small amounts, can cause the water to becoming corrosive.
• Alkalinity is the quantity of ions in water to neutralise acid or measure of water strength to neutralise acid.
• Main constituents are bicarbonate (HCO3- ), carbonate (CO32- ) and hydroxide (OH- ) ions from mineral dissolved in water and air, as well as from human activities such as fertilizers, detergent, and pesticide.
• Alkalinity gives water a non pleasant taste.
• Alkalinity's reaction between alkaline constituent and cation (positive ion) can produces precipitation in pipe.
• Hardness is a measure of "multivalent” cations in water such as Ca2+, Mg2+, Fe2+, Mn3+ from natural mineral on earth, it can cause causes excessive soap usage, form precipitate on hardware and in pipes increasing temperature and pH.
• Recommended Iron concentration in Water Supply is 0.3 mg/L where as the desirable concentration of Mn in drinking water is 0.01 – 0.05 mg/L
• Fluoride comes from mineral, it is not good for health if taken in high concentration but a concentration of 1 mg/L is good for the growth of children teeth.
• Excessive concentration of fluoridewill affects one's teeth colour and causes problem in bone growth.
• Metals can be toxic or Non Toxic.
• Non Toxic metals Ca2+, Mn2+, Fe2+, Zn2+, Al3+, Cu2+ etc are dangerous for health in high concentration, can be from Mineral readily available from nature with an effect of changing colour, odour, taste and turbidity as well as deteriorating eone's health (at high concentration).
• Toxic metals stored up in food chain e.g. Pb2+, Hg2+, Cd2+ are from human activities such as mining and industries and can cause dangerous diseases such as cancer, abortion and deformation in newborn baby.
• For Domestic Water Pb metals level should be < 0.05 mg/L, Hg < 0.02 mg/L, Cd < 0.01 mg/L
• Nutrients are composed mainly of - N and P.
• Nitrogen (N) - inorganic nitrogen is mainly present as nitrate (NO3–) and ammonium (NH4+), but also as dissolved nitrogen gas (N2), nitrite (NO2–), nitrous oxide (N2O); and ammonia (NH3) from domestic and industrial waste water, decomposition to a simple compound as well as from animals and human wastes and chemicals such as fertilizers with an effect of causing NO3- poisoning in human and animal babies or excessive algae breeding and aquatic plants
• Phosphorus (P) makes up dissolved orthophosphate (PO–³) from soil, chemicals, fertilizer, and domestic and human with an effect of excessive algae breeding and aquatic plants or at 0.2 mg/L may disturb coagulation process in water treatment plant.
• For Domestic Water Supply Nutrients should read PO4- < 50.0 mg/L
• Hartbeespoort Dam water quality is hyper-eutrophic due to continuous inflow of excess phosphate from sewage and via sediments.
• Eutrophication results from high nutrient concentrations causing excessive biological growth (usually algae).
• It can occur naturally in aging freshwater systems.
• Artificial (human-induced) eutrophication can degrade water quality and threatens aquatic species.
• High algae levels decrease the penetration of sunlight through the water column which hinders photosynthesis of water plants and can release compounds with bad odour and tastes, or toxic effects and also reducing dissolved oxygen in water.

Biological parameters

• The biological characteristics of a water body are made up of a variety of living organisms found in water.
• Many pathogens can enter the water system in sewage (human and animal waste).
• Organisms can cause illness when directly consumed by humans and animals.
• Water borne diseases such as dysentery, cholera, typhoid, gastro-entertitis and hepatitis are a cause of disease and poor health in the SADC region.
• Organisms can cause a bad taste and odour, as well as creating corrosion and slime production.
• Parameters from biological sources are associated with "nuisance" in raw water transport, treatment, storage, and distribution.
• May be responsible for some health implications/illness.