Hesti Lestari Tata

Segregate or Integrate for Multifunctionality and Sustained Change Through Rubber-Based Agroforestry in Indonesia and China

Rubber (Hevea brasiliensis L.) production systems have conserved forest biodiversity in some parts of Asia and are a threat elsewhere. A holistic view on these two sides of the coin is needed. The roles planted trees and agroforestry play in the transformation of lives and landscapes depend on the stage of “forest transition” and the spatial configuration, segregation or integration, of the landscape. “Forest transitions” need to be understood at the level of the actual pattern of change, (one level up) at the level of drivers of change, and (one level down) at the level of consequences for ecosystem goods and services. To close the loop on a feedback mechanism, forest transitions also need to be understood at the level of mechanisms that link desirable or undesirable consequences of changes in tree cover to the drivers, providing positive or negative feedback. “Forest ecosystem services” can be partially fulfilled by agroforests as a form of domesticated forest. We revisit the theoretical framing of agroforests as part of forest transition and discuss a case study of the rise and decline of complex rubber agroforests in lowland Sumatra (Indonesia) and the recent expansion of monoculture rubber in China replacing agroforestry systems. Both cases indicate a complex of driving and conditioning factors but also a current lack of incentives to reverse the trend toward landscape segregation. Complex agroforests represent an intermediate stage of intensification, between natural forest and home garden, and may occupy an intermediate stage in the way landscapes develop under the influence of land users and other stakeholders. Although complex agroforests represent considerable value (biodiversity and carbon stocks) of relevance to external stakeholders, incentive systems for the land users need to match these values; otherwise, these systems will disappear when more intensified and simplified tree crop systems take over. Current analysis of the choices in land sparing versus land sharing, and segregation versus integration, emphasizes the convex or concave nature of the bifunctional trade-off curves.

Mud, muddle and models in the knowledge value-chain to action on tropical peatland conservation

Tropical peatlands are known not only for their high, area-based, carbon emissions in response to land-use change but also as hot spots of debate about associated data uncertainties. Perspectives are still evolving on factors underlying the variability and uncertainty. Debate includes the ways of reducing emissions through rewetting, reforestation and agroforestry. A knowledge value-chain that is long and complex links (a) fundamental understanding of peat and peatland processes leading to sciencebased quantification and default values, (b) willingness and (c) ability to act towards emission reduction, and ultimately (d) to local, national and global actions that effectively provide rules, incentives and motivation to conserve peat and reduce emissions. We discuss this value chain, its stakeholders and issues that still remain partially unresolved. We conclude that, to shorten the denial and conspiracy-theory stages of debate that otherwise slow down steps B and C, networks of international and national scientists have to be involved at the early stage of identifying policysensitive environmental issues. Models span part of the knowledge value-chain but transition of analysis units requires specific attention, from soil volumes through area and commodity flows to opportunities for reductions. While drainage of peatlands triggers landscape-scale increases in emissions, factors beyond drainage depth, including nutrient supply, may have a major influence on decomposition rates. Attempts to disentangle the contributions of plant and peat-based respiration in surface flux measurements involve assumptions that cannot be easily verified in comparisons between land uses. With progress on A leading to new internationally accepted defaults and with resistance on step B reduced, the reality of C and lack of working solutions for D is currently constraining further progress.

Prioritizing underutilized tree species for domestication in smallholder systems of West Java.

This paper provides an overview of a tree species prioritization study of underutilized tree species in a participatory tree domestication program for smallholders in Indonesia. The study was conducted in three villages of Nanggung sub-district, Bogor district via farmer surveys, focus group discussion, SWOT analysis and evaluation of markets and germplasm sources. Five priority species were identified: Manglietia glauca, Parkia speciosa, Durio zibethinus, Gmelina arborea and Sandoricum koetjape. These species are promising components of agroforestry systems to enhance smallholder livelihoods and can grow under the low management conditions common in smallholder systems. They represent indigenous and exotic tree types that produce timber, fruit or spices within the domestication continuum. Furthering the domestication and utilization of these species requires the identification and dissemination of available germplasm sources, the dissemination of high-quality germplasm and the development of farmer-friendly propagation and tree management practices. Also, as with most smallholder systems, the marketing practices for the products of these five species require improvement, starting with the production of reliable quantities of high quality tree products.