4.b. global implications of water and carbon management

wetland restoration CC

Types: freshwater marshes, salt marshes, peatlands, floodplains, mangroves.

Key feature: water table at/near the surface, causing permanent saturation.

importance= Cover 6–9% of Earth’s land surface. Contain 35% of the terrestrial carbon pool. Destruction releases large amounts of CO₂ and CH₄. pressures= Population growth, economic development, urbanisation. In the lower 48 US states, wetland area has halved since 1600. Loss also harms biodiversity and wildlife habitats. Wetlands valued as major carbon sinks. In 20th century, Canada’s prairie provinces lost 70% of wetlands.

Canadian prairie restoration data= Restored wetlands store on average 3.25 tonnes C/ha/year. 112,000 ha targeted for restoration. Expected sequestration: 364,000 tonnes C/year.

Policy & protection= International Convention on Wetlands (Ramsar). EU Habitats Directive. UK initiatives: Up to 400 ha of grade 1 farmland in east Cambridgeshire being reconverted. Helps meet UK target of 500 ha restored by 2020. Additional targets: 140,000 ha by Jan 2028, 500,000 ha by 2042 for wildlife-rich habitat (including wetlands). Similar restoration occurring in Somerset.

Restoration methods= Raise local water tables to recreate waterlogged conditions. Floodplains: reconnect rivers by removing embankments and enabling controlled floods. Coastal marshland: restore by breaching sea defences. Elsewhere: maintain high water levels via Blocking or diverting drainage ditches, Installing sluice gates.

afforestation CC

Planting trees in deforested areas or areas never previously forested. Trees act as carbon sinks, helping reduce atmospheric CO₂ in the medium to long term.

Environmental benefits= Reduces flood risk. Decreases soil erosion. Increases biodiversity.

Protecting existing forests= Protecting tropical forests from loggers, farmers and miners is an inexpensive method of reducing greenhouse gas emissions. UN REDD (Reducing Emissions from Deforestation and Forest Degradation): Gives developing countries financial incentives to conserve rainforests. Established projects include: Amazonia (Puras, Russas-Valparaiso) and Lower Mississippi

China’s large-scale afforestation programme= Massive, government-led project launched in 1978. Goal: afforest 400,000 km² by 2050 (≈ size of Spain). Between 2000–09, 30,000 km² planted with non-native, fast-growing species (e.g., poplar, birch). Broader purpose: combat desertification and land degradation in northern China’s semi-arid regions. Additional figure: 44,500 km² afforested by 2024.

agricultural practices CC

Unsustainable agriculture & carbon emissions= Unsustainable practices include: over-cultivation, overgrazing, excessive intensification. These lead to soil erosion and release large quantities of carbon into the atmosphere. Intensive livestock farming produces 110 million tonnes/year of CH₄. Significant CH₄ sources also include: Flooded padi rice fields. Uncontrolled decomposition of manure.

Land & Crop Management Strategies= Zero tillage: Growing crops without ploughing. Conserves soil organic content, reduces oxidation and wind/water erosion.

Polyculture: Growing annual crops interspersed with trees. Trees give year-round ground cover and protect soils from erosion.

Crop residues: Leaving stems and leaves on fields after harvest. Provides ground cover, reduces erosion and soil drying.

Avoid heavy machinery on wet soils: Prevents compaction and reduces risk of surface runoff and erosion.

Contour ploughing & terracing: Used on slopes to reduce runoff and erosion.

Reducing CH₄ from rice production: New rice strains that grow in drier conditions ⇒ produce less CH₄. Ammonium sulphate can be applied to inhibit microbial CH₄ production.

Livestock Management= Improving feed quality reduces enteric fermentation ⇒ less CH₄ produced. Methane inhibitors can be mixed with livestock feed.

Manure Management= Control decomposition to reduce CH₄ emissions. Store manure in anaerobic containers and capture CH₄ for renewable energy.

international agreements to reduece emissions CC

Climate change affects all countries. Requires international co-operation, but progress has been uneven. Some major emitters have prioritised narrow self-interest for political and economic reasons.

Kyoto Protocol (1997) Until recently, the only significant international climate agreement. Most rich countries agreed to legally binding CO₂ reductions. Developing countries, including major polluters like China and India, were exempt. USA and Australia refused to ratify the treaty. Expired in 2012.

Paris Climate Agreement (2015, implemented 2020) New global agreement reached after years of negotiation. Aims: Reduce global CO₂ emissions to below 60% of 2010 levels by 2050. Keep global warming below 2°C. Targets are voluntary, not legally binding. A timetable for implementation is not yet agreed.

Additional global target= Global greenhouse gas emissions must fall 43% by 2030 (relative to 2019) to stay within the 1.5°C limit. Support for poorer countries= Rich countries will provide funding and technologies to help poorer countries meet targets.

They argue that rich countries should bear the main responsibility for global CO₂ cuts because:

Development needs: China and India are still relatively poor. Industrialisation using fossil fuels is essential to raise living standards to developed-world levels.

Historical responsibility: Europe and North America caused most emissions during their industrialisation. Therefore they are largely responsible for today’s global warming and climate change.

cap and trade CC

An international, market-based system to limit CO₂ emissions. Businesses receive an annual emissions quota (“cap”).

How it works: If a business emits less than its quota, it earns carbon credits. These credits can be traded on international markets. If businesses exceed their quota They must buy additional carbon credits or Face financial penalties.

Carbon offsets: Credits awarded for emissions-reducing schemes, including: Afforestation, Renewable energy projects, Wetland restoration

Offsets can be purchased to compensate for excessive emissions elsewhere.

forestry WC

Forests play a crucial role in the global water cycle. Recognised by multilateral agencies such as the United Nations (UN) and World Bank. These organisations fund programmes to protect tropical forests.

Key international programmes: UN REDD (Reducing Emissions from Deforestation and Forest Degradation)= Supports 65 countries. World Bank’s Forest Carbon Partnership Facility= Works with 47 developing countries across Africa, Asia-Pacific and South America.

Financial incentives= Based on a combination of: Carbon offsets, Direct funding. Aim: protect and restore forests.

Brazil — Example of Large-Scale Forest Protection

Support from global organisations= Brazil receives support from: UN, World Bank, World Wildlife Fund, German Development Bank, Amazon Regional Protected Areas (ARPA) programme, Covers nearly 10% of the Amazon Basin. Areas are strictly protected.

Benefits of the programme: Stabilises the regional water cycle. Offsets 430 million tonnes of carbon per year. Supports Indigenous forest communities. Promotes ecotourism. Protects a genetic bank of thousands of plant species.

water allocations WC

Global water use: Agriculture = 72% of water withdrawals, 90–93% of consumption. Industry = 15% of withdrawals, 4% of consumption. Domestic = 13% of withdrawals, 3% of consumption. Major losses from evaporation, seepage, and inefficient management.

Improving water management= Reduce evaporation: mulching, zero soil disturbance, drip irrigation. Reduce runoff on slopes: terracing, contour ploughing, vegetative strips. Boost supply: water harvesting and storage in ponds/reservoirs. Wastewater recycling (agriculture, industry, urban) is technically possible but rare outside developed countries.

Water allocation in semi-arid regions= Used where water scarcity is severe. Lower Indus Valley (Pakistan): Punjab + Sindh receive 90% of the Indus flow. US Colorado Basin: water allocated to California, Arizona, Nevada, Utah, New Mexico. In both regions, most water is used for irrigation.

drainage basin planning WC

Most effective scale for integrated/holistic management. Allows coordination of conflicting demands from: Agriculture, industry, domestic use. Wildlife, recreation, leisure. These demands affect water quality, river flow, groundwater, habitats, and biodiversity.

Key management targets= Runoff, Surface water storage, Groundwater levels

Managing runoff= Reforestation in upland catchments. Reducing artificial drainage. Increasing permeable surfaces in urban areas.

Improving surface water storage= Conserving and restoring wetlands. Using floodplains for temporary storage.

Maintaining groundwater= Limit abstraction. Use artificial recharge: water injected into aquifers via boreholes.

Drainage basin management in England & Wales= Guided by the EU Water Framework Directive (WFD)—still retained in UK law. 11 river basin districts identified, including Severn, Thames, Humber. Each district has a River Basin Management Plan created by the Environment Agency and Defra.

Plan targets include: Water quality, Abstraction rates, Groundwater levels, Flood control, Floodplain development, Habitats and wildlife status