Agro-forestry as an adaptation measure

Tree management practices can reduce the effects of climate change on the ecosystem by increasing ground cover, improving soil structure and infil-tration, decreasing erosion by water and wind. Water erosion, especially under extreme rainfall conditions and in already degraded land is a major hazard. However, water erosion is not a major concern on dry, flat, rolling lands, rather, wind erosion is a major problem in low-rainfall, high evapo-ration areas (Leihner 2000). Thus, conserving water and improving water use efficiency of crops are the adaptations that are practiced. Water is a limiting resource in semi-arid areas, but in West Africa it normally ranks second after nutrient limitations (Leihner 2000). The author suggests that when designing water-conserving cropping systems, components that reduce evaporation but have no water demand on their own should be preferred.

Indigenous and improved agro-forestry, that is, the cultivation of trees with crops, pastures or livestock, can address many challenges that farmers face in a variable climate (WOCAT 2007). In SSA, agroforestry (as live fences, fruit trees, alley cropping, shelter belts) is widespread. Agro-for-estry can be another way to reduce competition on the use of crop residues for fodder, mulching and burning. If trees planted can provide fodder for livestock, farmers may be more willing to leave the residues to cover the soil after harvests. Planting trees between crops can help prevent soil ero-sion, restore soil fertility, and provide shade for other crops.

Shelterbelts and windbreaks, that is, trees planted to block or reduce wind speeds, also maintain soil moisture and reduce evaporation (Stigter et al.

2005). However, windbreak vegetation may compete with crops for water;

areas, a vegetation cover maintained throughout the major part of the year conserves water best (Leihner 2000). The author also highlights that lo-cally adapted crop varieties have an unrealized potential that can be tapped through improved management practices. Under changing climate condi-tions, the resistant characteristics of crops are crucial hence combining high yield potential with better yield stability should be targeted.

Live fences, that is, trees planted around homesteads or cultivated land, aim to protect the enclosure from roaming livestock and in many cases to provide fodder for livestock. Grevillea robusta (originally from Australia) are widespread in coffee and tea plantations of East Africa and in the drier areas of the Mount Kenya region. Grevillea is used to mark the boundary of plots, for alley cropping, for fuelwood, wood and building materials.

The tree serves as wind break and contributes to nutrient recycling due to its deep roots. WOCAT (2007) notes that Grevillea alone is not used for soil erosion control but in combination with other measures like fanja juu, bench terraces or other vegetative measures. Vegetative hedges are also used as contour lines to slow runoff down the slope and protect the soil from erosion. An example is the use of vertiver grass (Vetveria zizani-oides) in Kwa-Zulu Natal, South Africa (WOCAT 2007).

In addition, trees and shrubs sequester more carbon than crops, thereby contributing to mitigate climate change. These arguments speak for the participation of farmers in carbon emissions trading (see Box 13). Besides benefits from improved environmental services and yields, small-scale agro-forestry could provide farmers with additional incomes from carbon payments, no matter how small. However, the small quantity of seques-tered carbon and the absence of a third party organisation to administer agro-forestry projects for carbon sequestration and bear the high transac-tion costs, delay the access of many smallholder dominated areas to addi-tional income from carbon trade (Takimoto / Nair / Alavalapati 2008).

Although smallholder farmers in many SSA regions have been practicing agro-forestry for ages, the value of carbon is not a factor in their decisions.

This means that tree species are chosen for other factors, such as wood production, fodder production or fruit production. Thus, such trees se-quester carbon at varying levels. Ginoga, Wulan and Djaenudin (2004) suggest that the species in agro-forestry systems can be changed to longer-lived trees that sequester more carbon, if carbon payments are large enough to provide an incentive to farmers.

Since farmers already practice agro-forestry, existing agro-forestry sys-tems are part of the baseline and therefore not additional to what would have occurred in the absence of a CDM project. For example, traditional agro-forestry systems in Ségou, a semi-arid region of Mali, were found to have high carbon stock in their biomass and soil, but little potential for sequestering additional carbon (Takimoto / Nair / Alavalapati 2008; Taki-moto / Nair / Nair 2008). Thus, additionality criteria need to be identified.

Ginoga, Wulan and Djaenudin (2004) suggest that addressing the barriers to more widespread adoption of agro-forestry such as the lack of technical skills or inadequate investment capital to establish the trees, might meet the additionality requirement.

Thus, for farmers to participate in carbon trading, modifications of various trading schemes are needed, in particular, the major ones such as the European Union emission trading scheme. Since smallholders farm only small portions of land, they need to form cooperatives or be assisted in doing so in order to access carbon markets where large carbon volumes are traded. An institution is also needed to arrange for the certification of carbon sequestration, to apply for carbon payments and distribute funds to the farmers (Fritschel 2006).

In the context of climate change, crops are no longer only for food, fibre or industrial raw material but also as carbon assets. Where agro-forestry is not yet established, the costs of planting trees might be too high for the smallholders and may need external support. However, the fact that SSA has gained very little from the current carbon trading schemes (in contrast to large commercial farms in Asia) hints at the inadequate know-how and resources required to establish such schemes as well as the disadvanta-geous structures of the CDM scheme of the UNFCCC whereby most certi-fying companies are located outside Africa. Thus, development coop-eration needs to support SSA governments to set up the necessary infra-structure at country levels to simplify access to the carbon markets.

Box 7: Agro-forestry and its eligibility for programmatic CDM Afforestation and reforestation are eligible under CDM but depending on agro-forestry types and how a party defines a forest, agro-forestry may or may not be eligible under the CDM small-scale afforestation or reforestation projects. "Small-scale afforestation and reforestation pro-ject activities under the CDM" are those that are expected to result in net anthropogenic greenhouse gas removals by sinks of less than 16 kilotonnes of CO2 per year and are developed or implemented by low-income communities and individuals as determined by the host Party"

(UNFCCC 2008a, FCCC/KP/CMP/2007/9/Add.1, Decision9/CMP.3, p.

26)

Thus, those that practice agro-forestry could benefit from the global carbon credit market. However, under the Kyoto Protocol, only biomass carbon that is newly sequestered is recognized as "tradable" carbon, meaning that traditional agro-forestry systems are not likely to qualify as carbon sequestration projects.

Despite this limitation, agro-forestry could be eligible for a program-matic CDM of small-scale afforestation and reforestation (UNFCCC 2006a, FCCC/KP/CMP/2005/8/Add.1, Decision 5–7/CMP.1, p. 61 ff.) whereby the district, provincial or national government (or even private entities) offer farmers incentives through a CDM programme to pro-mote afforestation and reforestation. A programmatic CDM refers to a programme of activities (PoA) and "is a voluntary coordinated action by a private or public entity which coordinates and implements any pol-icy/measure or stated goal (i. e. incentive schemes and voluntary pro-grammes), which leads to anthropogenic GHG emission reductions or net anthropogenic greenhouse gas removals by sinks that are additional to any that would occur in the absence of the PoA, via an unlimited number of CDM Programme Activities (CPAs)" (CDM-Executive Board 2007, EB 32, Annex 38, paragraph 1).

Source: Mentioned in this Box

Contributions to resilience to climate change:

The contributions of agro-forestry to resilience to climate change are similar to those of crop management practices. However, the contributions of agro-forestry (carbon sequestration nitrogen fixation, source of income) are of a longer-term nature and of larger quantity than those of crop man-agement practices, both of which are complementary.