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How sustainable land management affects climate change

Climate change and agriculture
Sustainable land use and management is an important tool for both mitigating against and adapting to climate change. The latest Intergovernmental Panel on Climate Change (IPCC) report in 2007 presented the possible scenarios resulting from climate change which predict that dry areas around the world may become drier and wet areas may become wetter. Furthermore, South Africa is predicted to be one of the countries that will experience one of the most severe effects, with the west suffering intensification and increased frequency of drought accompanied by flash floods and the east increased rainfall and flooding. The country’s biodiversity and water resources have been identified as two areas of highest vulnerability. This has major implications for agricultural sector in particular and thus food security.

Changes in climate are already starting to effect temperature and rainfall patterns in some parts of the world and farmers are seeing reduced crop yields. At the same time, the human population is predicted to increase to 9.1 billion by 2050 which will further effect food security and cause a loss of biodiversity as arable land is expected to expand in order to feed the growing population. This is especially the case in Latin America and Sub-Saharan Africa. The expansion of cultivated land from virgin uncultivated land is known as Land Use and Land Use Change and Forestry (LULUCF). It poses a significant threat to climate change mitigation measures as it is estimated that 20% of the global greenhouse gas (GHG) emissions are generated in this land conversion process. Conversion to cropland can result in 95% loss of above-ground carbon and up to 60% loss of below-ground carbon. The amount of carbon dioxide (CO2) released depends on the type of soil e.g. wetlands or peatlands, act as sinks to 20% of the world’s CO2 and thus conversion of it to croplands releases high amounts of CO2.

Excluding CO2 emissions from land use change, the other source of GHGs in the agricultural sector are through methane, nitrous oxide and CO2. Nitrous oxide has around 298 times the Global Warming Potential (GWP) of CO2. It is released during the production of manufactured fertilizer. CO2 is released by burning fossil fuels (e.g. diesel in tractors, farm vehicles, machinery and the production of agricultural chemicals) as well as the disturbance of soils and changes in land use and land management which include the removal and burning of vegetation and forests. Methane has 25 times the GWP of CO2 and is released from the digestive systems of ruminant livestock as well as from manures and slurries. It can be reduced per unit of production through improved livestock health, modification of animal diets and reducing stocking numbers.

What can farmers do?
Farmers and landowners are in a unique position as they have the opportunity to mitigate climate change and adapt to it simultaneously by engaging in sustainable land management practices which include water conservation, crop and livestock management, soil management, the restoration of degraded land and biodiversity conservation. These measures result in the two-fold effect of improving ecosystem health and curbing GHG emissions released into the atmosphere.

Farming in this way is productive and increases the yields without compromising the natural resources. For example, in areas that may be prone to increased rainfall and flash floods, the restoration of soils and vegetation, especially in wetland and riparian areas will help buffer against these impacts due to the increased capacity of the soil to absorb water. Alien clearing in conjunction with re-vegetation can also assist in improving base flows of water. Similarly for areas that may experience water shortages, drought resistant crops can be used to safeguard against low rainfall such as sorghum, cassava and sweet potatoes. If soils are managed properly, they have the potential to effectively assist in mitigating climate change as they can store carbon and nitrogen. Research shows that in Africa, 20-40 teragrams (Tg) of carbon per year can be sequestered in soils though improved management and restoration within degraded and non-degraded croplands and grasslands. Furthermore, those soils can continue carbon sequestration for up to 50 years.

The Climate Action Partnership (CAP) is an alliance of eight of South Africa’s conservation NGOs who are working together on climate change mitigation and adaptation solutions through the land use sector. CAP, through its partners, is involved in various initiatives which are implementing sustainable crop and livestock farming techniques through ecosystem-based initiatives. The projects aim to rehabilitate freshwater systems and reforest areas through planting indigenous vegetation. Activities also include restoring degraded soils through fire management, while preventing overgrazing and erosion through the reduction of livestock numbers. Areas are conserved through securing stewardship partnerships with private and communal landowners. Management guidelines are written outlining ways of improving natural resource usage, such as water management by removing alien invasive vegetation and restoring wetlands and corridors along rivers.

Farmers, though the avoidance of cultivating marginal land and the conservation of natural corridors can also help maintain functioning ecosystems so that plants and animals are able to move to new areas as required which is an important climate change adaptation mechanism. Rivers and wetlands can provide ideal corridors as they often run through various farms and landscapes. The maintenance of the natural vegetation provides buffers against flooding and prevents soil erosion. Furthermore, avoidance of cultivation of these habitats averts high water tables and flooding and salinisation of soils. In exchange for loss of revenue from unfarmed land, farmers can benefit financially from ecotourism and from incentives like Payment for Ecosystem Services (PES), which are beginning to emerge in South Africa as viable economic models within the green economy. CAP, through its partners, in these ways helps to support local communities by creating alternative livelihoods as a means of adapting to climate change and securing habitats for endangered species.

Thus, ecosystem‐based strategies can offer cost‐effective, proven and sustainable solutions to climate change, contributing to and complementing other national and regional adaptation strategies.

TReduced emissions from deforestation and degradation (REDD)
Another attractive measure for sustainable land management in the mitigation of climate change is the conservation of forests, savannas and other woody areas. To stimulate the protection of forests, the United Nations Framework Convention on Climate Change (UNFCCC) is in the process of introducing the Reduced Emissions from Deforestation and Degradation in developing countries (REDD+) mechanism. Financial incentives are created so that forested areas are preserved to prevent further deforestation from harvesting of timber products as well as preventing conversion of forest to agricultural land, both processes which produce GHG emissions. Vital to the REDD+ mechanism is achieving substantial co-benefits for biodiversity conservation and human development. The Climate Community and Biodiversity Alliance are also in the process of establishing safeguards and standards for REDD projects (see www.climate-standards.org.)

Forests play an essential role as they can store large amounts of carbon depending on their location. According to the UNFCCC, global forests are estimated to store more than 600 Giga tonnes (Gt) of carbon. Currently, large amounts of this land are being lost to agriculture. Consequently, in the period between 2000-2005 four million ha were lost releasing about 0.25 Gt CO2. Worldwide, the IPCC has estimated emissions from deforestation to be more than 5.8 Gt CO2/year since 1990. African forests, which include the Congo Basin, the Maputaland-Pondoland-Albany region and Subtropical thicket of South Africa, make up 16% of the world’s forest area and are important carbon sinks. These regions are estimated to contain over 100 Gt carbon. Besides providing food, fuel and shelter, forests have important cultural value as they are sources of traditional medicines and sites for conducting sacred rituals. Therefore, during times of social or environmental pressure, these peoples’ livelihoods and access to food are directly impacted upon.

Deforestation has led to the reduced ability of ecosystems to regulate water flows and its remediation, placing additional burdens on these communities. For this reason, some consider the concerns regarding degradation and deforestation in Africa to be more urgent than climate change itself. However, it is important to recognize that measures to reduce these pressures also coincide with both those of adaptation and mitigation to climate change.

Thus to reduce these vulnerabilities, reforestation and rehabilitation must be implemented in a way which is aligned with the sustainable management of forests. This may include managing fire, diseases, alien invasive vegetation, forest species composition and structure, minimizing fragmentation, creating corridors, as well as conserving biodiversity. In order to achieve this there is a need for implementers to consult with communities, drawing on local knowledge and experience to secure land tenure agreements. The objectives of such projects should align with those of the communities involved, so that there is a sense of community ownership and benefit.

Conclusion
These approaches show that sustainable, climate-resilient agriculture is the key to enabling farmers to increase food security and adapt to climate change. In this way farmers through sustainable land management practices will not only be able to “climate proof” themselves through improved food security but will also contribute to ecosystem restoration and biodiversity conservation. Sustainable land management and climate change cannot be decoupled, as these practices engage both climate change adaptation and mitigation measures simultaneously. Thus protecting the services of ecosystems helps build the resilience of people to climate change by creating jobs, educating communities on these issues and maintaining better functioning communities. For more information see www.cap.org.za and for the Green Choice living farms reference available at:
http://www.wwf.org.za/what_we_do/outstanding_places/drivers_of_change/food_production/

Simisha Pather-Elias
Climate Action Partnership
s.pather-elias@conservation.org


Click the image to enlarge: Global distribution of the potential sequestration of carbon in soils of croplands. Source UN Food and Agriculture Organization
Global distribution of the potential sequestration of carbon in soils of croplands. Source UN Food and Agriculture Organization
Click the image to enlarge: Global degradation and deforestation illustrating forest cover in South Africa. Source: Millennium Ecosystem Assessment
Global degradation and deforestation illustrating forest cover in South Africa. Source: Millennium Ecosystem Assessment
Click the image to enlarge: Map of carbon sequestrated in vegetation and soil in South Africa, showing that currently the eastern coast has the highest stocks. Source: UN Environmental Programme.”
Map of carbon sequestrated in vegetation and soil in South Africa, showing that currently the eastern coast has the highest stocks. Source: UN Environmental Programme.”
Posted: 12/21/2010 (3:47:54 AM)

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