2. Deforestation and Desertification Comprehensive Study Notes

Global Overview and Historical Context of Deforestation

• Definition and Evolution: Deforestation is the process whereby people use trees for resources or clear the land for other purposes. This activity has been ongoing since the transition from hunter-gatherer lifestyles to sedentary lifestyles.

• Historical Forest Cover Estimations:     * Pre-agricultural times: Estimated global forest cover was approximately $5 \times 10^9\,\text{hectares}$.     * Year 2000 (FAO Estimate): Natural and plantation forests covered approximately $3.9 \times 10^9\,\text{hectares}$.

• Ecological Value: The core of deforestation study involves assessing the ecological services provided by forests and the consequences of removing those services.

Drivers and Causes of Deforestation

• Primary Drivers (Socio-Economic):     * Poverty and population growth.     * Agricultural expansion and infrastructural development.     * Charcoal production.     * Weak governance and climate variability exacerbate these factors.     * Economic systems, such as capitalism, are considered potential drivers.

• Direct Drivers:     * Agriculture: Large-scale agriculture, plantations, and smallholder farming.     * Extractives: Logging, fuelwood collection, and mining.     * Infrastructure: Transport networks, hydroelectric power, and urban expansion.     * Others: Environmental factors like fires.

• Indirect (Underlying) Drivers:     * Demographic: Population growth and migrations.     * Economic: Market demand, finance, and investments.     * Technological: Production practices and agrotechnical change.     * Political: Policies, regulations, and incentives.     * Environmental: Climate, soil quality, and terrain.

• Response Types and Approaches (WWF Framework):     * Area-based: Conservation and Indigenous Peoples and Local Communities (IPLC) rights.     * Commodity or Sector Specific: Legality of production and sustainable supply chains.     * Environmental Services: Responsible finance and integrated approaches like REDD+ (Reducing Emissions from Deforestation and Forest Degradation) and sustainable jurisdictions.

Regional and National Trends in Africa

• General African Statistics: Africa possesses approximately $7.03 \times 10^8\,\text{hectares}$ of forest. Deforestation rates vary by ecosystem.

• Swaziland: Lost approximately $1700\,\text{ha/year}$ between the period of $1990$ and $2015$.

• Angola (Miombo Woodlands): Deforestation rates dropped during the civil war but tripled post-$2002$ due to agricultural expansion and resettlement.

• Spatial Distribution: Forest loss is heavily concentrated near roads, urban centers, and transport corridors. Notably, over $80\%$ of forest loss is occurring in just $14$ countries.

• Indigenous Knowledge Systems (IKS):     * KwaZulu-Natal: Indigenous ecological knowledge is used for sustainable harvesting, species propagation, and conservation planning. Integration with scientific methods improves restoration.     * Challenges: Revitalizing IKS is hindered by youth disinterest and conflicts with modern scientific approaches.

Deforestation: The South African Perspective

• State of Forests (2010): South Africa had $3.97 \times 10^6\,\text{hectares}$ of natural forest, covering $4.3\%$ of its land area.

• Recent Forest Loss (2020): The country lost $3.03 \times 10^4\,\text{hectares}$ of natural forest, equivalent to $1.13 \times 10^7\,\text{tonnes}$ ($11.3\,\text{Mt}$) of $CO_2$ emissions.

• Humid Primary Forest (2002–2020):     * Lost $1.13 \times 10^4\,\text{hectares}$ of humid primary forest.     * This specific loss accounts for $0.61\%$ of the total tree cover loss.     * Total area of humid primary forest decreased by $9.0\%$ during this window.

• Total Tree Cover Loss (2002–2020):     * Total loss of $1.84 \times 10^6\,\text{hectares}$.     * This represents an $8.3\%$ decrease in tree cover since the year $2000$.     * Total emissions from this loss equal $9.44 \times 10^8\,\text{tonnes}$ ($944\,\text{Mt}$) of $CO_2e$.

• Regional Concentration: Deforestation is highest around densely populated areas to meet cooking and heating needs.

• Mitigation Opportunities: Since most deforestation is avoidable, the adoption of efficient cookstoves and a transition to clean energy could drastically reduce forest pressure.

Case Study: Thulamela Local Municipality, South Africa

• Biomass and the "6 F's": Biomass provides Food, Fuel, Feed, Feedstock, Fibre, and Fertiliser.

• Energy Dependency:     * Developing countries: $33\%$ of energy comes from fuel wood; nearly half the population depends on wood, dung, and crop residues.     * Industrialized countries: $3\%$ of energy is fuel wood.     * Africa: Fuel wood accounts for $60\%$ of final energy use.

• Thulamela Demographics: Home to approximately $618,462$ people in $228$ villages, primarily Venda people. Characterized by high unemployment and a low quality of life.

• Fuel Wood Consumption Patterns:     * Firewood is the major energy source.     * Collection occurs in communal forests and agricultural fields near homesteads.     * While dead/dry branches are preferred, high demand leads to the cutting and drying of green branches.

• Research Findings:     * Each household uses approximately $2\,\text{kg}$ of firewood per meal prepared.     * Firewood collection increases as productivity and income decline.     * Consequences include the immediate release of sequestered carbon when burned or the release of $GHGs$ during decay.

• Methodology:     * Household questionnaires and interviews with village/household heads.     * NDVI (Normalised Difference Vegetation Index): A remote sensing technique used to quantify the photosynthetic capacity of plant canopies and determine changes in vegetation cover.

Desertification: Definition and Drivers

• Official UN Definition: "Land degradation in arid, semi-arid, and dry sub-humid areas resulting from various factors including climactic variations and human activities."

• Alternative Term: Dryland Degradation.

• Biophysical Drivers:     * Climate variability and drought cycles.     * Soil erosion, vegetation loss, salinization, and pollution.

• Socio-Economic Drivers:     * Poverty, subsistence agriculture, and insecure land tenure.     * Market access issues and governance failures.

• Policy/Institutional Context: Weak coordination and a failure to integrate indigenous knowledge.

Specific Causes of Desertification

• Intensive Grazing: Utilizing too many or inappropriate types of animals on a specific piece of land. This leads to trampling, soil compaction, and reduced vegetation, which ultimately increases soil erosion.

• Overcultivation: Inappropriate fallow periods lead to nutrient depletion. The feedback loop involves: $\text{Vegetation loss} \rightarrow \text{Soil structure loss} \rightarrow \text{Soil erosion} \rightarrow \text{Further vegetation loss}$.

• Overexploitation: Clearing forested land for cultivation or fuel wood. Domestic use degradation often prevents vegetation from fully recovering even if it is not entirely removed.

• Climate Change:     * The IPCC 4th assessment report indicates all of Africa is likely to warm this century.     * Expected hydrological changes in Southern Africa during June-July-August, particularly in the western part of South Africa.     * Anthropogenic land alteration causes high-pressure circulation anomalies, resulting in drier conditions.

Land Degradation: Justice, Tenure, and Spatial Patterns

• The Conflict of Objectives: Policymakers must reconcile political commitments to redress historic land injustices (post-apartheid reforms) with international targets for biodiversity, carbon emissions, and Sustainable Development Goals (SDGs).

• Land Tenure Systems:     * Communal Tenure: Often associated with higher degradation rates, higher stocking rates, and more severe erosion due to lack of investment and overuse.     * Commercial Tenure: Generally has more effective management.     * Tenure Reform: Adaptive governance models (e.g., Namibia’s conservancies) and secure tenure improve restoration outcomes.

• Spatial Patterns:     * Drylands: Experience severe vegetative loss and gully formation, especially in communal escarpments.     * Sub-humid/Humid Areas: Rapid soil loss from floods, with hotspots on steep slopes.     * Southwestern Cape: Unique challenges from alien invasive species and water scarcity in a Mediterranean climate.     * Free State: Vulnerable to climate variability and unsustainable farming.

• Historical Perspective (Acocks' Theory):     * In $1953$, Acocks theorized that Africa would be engulfed by semi-arid Karoo vegetation by $2050$, with a "complete desert" following.     * Quaternary sedimentary sequences suggest vegetation change in the Karoo is dynamic and not always anthropogenic.