(Full document can be obtained via: http://www.fao.org/documents/card/en/c/cb2488en)
Products and services derived from trees in forests, on farmland and within other landscapes provide benefits to hundreds of millions of people in the tropics, but these benefits from the trees and their genetic resources have not been well quantified. This is the case, in part, because trade often takes place outside formal markets; there are a multiplicity of species, product sources and ways in which trees are used; and the value of genetic diversity within tree species has not been properly considered.
This study reviews what is known about the value of trees for tropical rural communities and considers the following:
• Non-timber products harvested from trees in natural and managed forests and woodlands.
• The various products and services obtained from trees planted and/or retained in agroforestry systems.
• The commercial products of tree commodity crops.
The study focuses, where possible, on the role of intra-specific genetic variation in determining the value of trees in supporting livelihoods in each of the above three contexts. The more systematic, standardized approaches to quantifying non-timber forest product (NTFP) value applied in the last decade or so have illustrated the importance of NTFPs for marginalized households and for women’s incomes. Analyses of wild tree foods from forests have considered the diversity of foods available but have also shown that availability does not necessarily mean that humans consume these foods. In the tropics, significant changes in fruit properties have taken place in many fruit trees over several millennia be- cause of human selection that better conforms to the communities’ food needs. Knowledge of these changes can help guide future domestications.
To improve the lives of rural people through NTFP harvesting, they need technical sup- port in harvesting and processing, business support to establish enterprises, and they need market information to be shared, among other interventions. The ecological implications and genetic aspects of NTFP harvesting regarding productivity, sustainability, etc. have received limited attention and require further research.
Database searches indicate a wide range of agroforestry tree products (AFTPs) such as timber, medicine and fuel, which are commonly mentioned. Examples that show larger benefits from having trees on farms are soil fertility replenishment, timber production and fodder provision. There are specific opportunities to bring into cultivation food trees through participatory domestication methods, making use of the great biological diversity found within and between indigenous fruit tree species in tropical regions, and improving human diets by filling nutritional gaps.
Human-driven climate change and forest displacement mean that tree products and services will in future be sourced increasingly from farms. Key constraints to agroforestry, however, must be addressed in policies, markets, and in developing and delivering appropriate high-quality tree planting material and farm management methods. Delivery systems should involve small-scale, local, entrepreneurial tree seed, seedling and clone suppliers, supported with business and technical training and with starter germplasm.
Many tree commodity crops are grown by smallholders, often in locations away from the centres of origin of the tree crops. This emphasizes the importance of international cooperation in exploiting genetic resources for sustaining and enhancing commercial production of these crops. The value of wild resources of tree commodity crops needs to be properly quantified. The geographic separation of origin and production centres for these commodity crops presents a dilemma for conservation, which also applies to other widely cultivated tree species.
Although tree commodity crops play an important role in supporting rural livelihoods, it will be necessary to better understand the complicating factors that result in land being converted to monoculture production systems, and to understand the impact of single- source incomes on a community’s food and nutritional security. Commodity varieties that are highly productive in mixed farming systems are needed, making use of intra- specific genetic diversity to develop varieties that most favourably interact with the other components of the farming systems.