what are the global management strategies available to protect the water and carbon cycle? Flashcards
(29 cards)
Management strategies designed to protect the global carbon cycle
Management strategies designed to protect the global carbon cycle as the regulator of the Earth’s climate
include wetland restoration, afforestation, sustainable agriculture practices and controls on greenhouse gas
emissions
Wetlands
include freshwater marshes, salt marshes, peatlands, floodplains and mangroves.
Their common feature is a water table at or near the surface causing the ground to permanently saturated.
Wetlands are important in the carbon cycle: they occupy 6-9% of the Earth’s land surface and contain 35% of the terrestrial
carbon pool.
pressure on wetland
environments
Population growth, economic development and urbanisation have placed huge pressure on wetland environments.
In the lower 48 US states the wetland area has halved since 1600.
Apart from loss of biodiversity and wildlife habitats, destruction of wetlands transfers huge amounts of stored CO2 and CH4 to
the atmosphere
Restoration programmes
However, climate change and the need to reduce CO2 emissions have led to a re-evaluation of the
importance of wetlands as carbon sinks.
In the twentieth century, Canada’s prairie provinces lost 70% of their wetlands.
Restoration programmes in this area have shown that wetlands can store on average, 3.25tonnes
C/ha/year.
The need for protection of wetlands as wildlife habitats as well as carbon stores is reflected in
management initiatives such as the International Convention on Wetlands and European Union Habitats Directive
Afforestation
Involves planting trees in deforested areas or in areas that have never been forested.
Because trees are carbon sinks, afforestation can help reduce atmospheric CO2 levels in the medium to long term and combat
climate change.
IT also has other benefits such as reducing flood risks and soil erosion, and increasing
biodiversity
REDD
Protecting tropical forests from loggers, farmers and miners is an inexpensive way of curbing greenhouse gas emissions.
The UN’s Reducing Emissions from Deforestation and Forest Degradation (REDD) scheme
incentivises developing countries to conserve their rainforests by placing a monetary value on forest conservation.
Several projects are already well established such as those in Amazonia and the Lower Mississippi.
In China
In China a massive government-sponsored afforestation project began in 1978. It aims to afforest 400,000km3 by 2050.
Unsustainable agricultural practices
Unsustainable agricultural practices such as over cultivation, overgrazing and excessive intensification often result in soil erosion and the release of large quantities of carbon to the atmosphere.
Intensive livestock farming produces 100 million tonnes/year of CH4 , a potent greenhouse gas.
Almost as important are CH4 emissions from flooded rice fields and from the uncontrolled decomposition of manure.
Agricultural practices to reduce greenhouse gas emissions
-Land and crop management (Zero tillage- growing crops without ploughing the soil thus conserving the soil’s organic content, reducing oxidation and the risk of erosion by wind and water, Introducing new strains of rice that grow in dryer conditions and therefore produce less CH4)
-Livestock management (Improving the quality of animal feed to reduce enteric fermentation so that less feed is converted to CH4; mixing methane inhibitors with livestock feed)
-Manure management (Controlling the way manure decomposes to reduce CH4 emissions. Storing strong manure in anaerobic containers and capturing CH4 as a source of renewable energy
international co-operation
Climate change affects all countries.
Solving the problem therefore requires international co-operation.
So far, co-operation has been patchy for a variety of economic and political reasons, some of the world’s largest greenhouse-gas emitters have opted to pursue narrow self-interest
Kyoto Protocol (1997)
Until recently the only significant international agreement to tackle climate change has been the Kyoto Protocol (1997). Under Kyoto, most rich countries agreed to legally binding reductions in their CO2 emissions, though controversially, developing countries and some of the biggest polluters (e.g. China and India), were exempted.
paris agreement
Kyoto expired in 2012 and after several rounds of negotiation, a new international agreement was finally reached called the Paris Agreement which aims to reduce global CO2 emissions below 60% of 2010 levels by 2050, and keep global warming below 2degrees.
However, countries will set their own voluntary targets which are not legally binding and a timetable for implementing them has yet to be agreed.
Meanwhile, rich countries will transfer significant funds and technologies to assist poorer countries to achieve their targets.
Major CO2 emitters such as China and India argue that global reductions in C02 emissions are the responsibility of rich countries because
-countries such as China and India are still relatively poor and industrialisation, based on fossil fuels energy, is essential to raise living standards to levels comparable with those in the developed world.
-historically, Europe and North America through their own industrialisation and economic development are largely to blame for contemporary global warming and climate change.
Cap and trade
offers an alternative, international market-based approach to limit CO2 emissions.
Under this scheme businesses are allocated an annual quota for their CO2 emissions.
If they emit less than their quota they
receive carbon credits which can be traded on international markets.
Businesses that exceed their quotas
must purchase additional credits or incur financial penalties.
=Carbon offsets are credits award to countries and companies for schemes such as afforestation, renewable energy and wetland restoration.
They can be bought to compensate for excessive emissions elsewhere
Management strategies to protect the global water cycle
Forestry- the crucial role of forest
crucial role of forests in the global water cycle is recognised by multilateral agencies such as the UN and World Bank.
They, together with other organisations and governments, fund programmes to protect
tropical forests.
UN’s REDD programme and the World Banks Forest Carbon Partnership Facility (FCPF)
fund over 50 partner countries in Africa, Asia-Pacific and South America.
Financial incentives to protect and restore forests
are a combination of carbon offsets and direct funding.
Brazil has received support from the UN, World Bank and World Wildlife Fund and the German Development Bank to protect its forests
The Amazon Regional Protected Areas (ARPA) programme
now covers nearly 10% of the Amazon basin.
The benefits are significant:
-Stabilising the regional water cycle
-Offsetting 430 million tonnes of carbon a year
-Supporting indigenous forrest communities
-Promoting ecotourism
-Protecting the genetic bank provided by thousands of plant species in the forests.
Water allocations
In countries of water scarcity governments have to make difficult decisions on the allocation of water resources.
Agriculture is by far the consumer as globally it accounts for 70% of water withdrawals and 90%
of consumption.
Wastage of water
occurs through evaporation and seepage through inefficient water management (e.g.
over-irrigating crops).
Improved management techniques which minimise water losses to evaporation
include mulching, zero soil disturbance and drip irrigation.
Losses to run-off on slopes can be reduced by
terracing, contour ploughing and the insertion of vegetative strips.
Meanwhile, better water harvesting, with storage in ponds and reservoirs, provides farmers with extra water resources.
Recovery and recycling of waste water
Recovery and recycling of waste water from agriculture, industry and urban populations is technically feasible, but as yet little used outside the developed world
