A new framework to enable equitable outcomes: resilience and nexus approaches combined

Managing integrated social-ecological systems to reduce risks to human and environmental well-being remains challenging in light of the rate and extent of undesirable changes that are occurring. Developing frameworks that are sufficiently integrative to guide research to deliver the necessary insights into all key system aspects is an important outstanding task. Among existing approaches, resilience and nexus framings both allow focus on unpacking relationships across scales and levels in a system and emphasize the involvement of different groups in decision making to different extents. They also suffer weaknesses and neither approach puts social justice considerations explicitly at its core. This has important implications for understanding who wins and loses out from different decisions and how social and ecological risks and trade-offs are shared and distributed, temporally and spatially. This paper conceptually integrates resilience and nexus approaches, developing a combined framework and indicating how it could effectively be operationalized in cases from mountain and mangrove social-ecological systems. In doing so, it advances understanding of complex social-ecological systems framings for risk-based decision making beyond that which could be achieved through use of either resilience or nexus approaches alone. Important next steps in testing the framework involve empirical and field operationalization, requiring interdisciplinary, mixed method approache

National and international policies for tropical rain forest conservation—A quantitative analysis for Cameroon

This paper provides a numerical general equilibrium assessment of policies to reduce tropical deforestation in Cameroon. Market failure—mainly in the form of national and international externalities—and policy failures—such as highly distorted product markets—are identified as major sources of overexploitation. The ecological effects of deforestation control are shown to depend crucially upon its impact on land use patterns whereas its efficiency effects hinge on the manner in which a specified set-aside target is achieved. If the international community wants to ensure a higher level of protection of these forests, and to do so within a market-based system, the provision of conditional financial resources is neceassary. Copyright Kluwer Academic Publishers 1993(JEL): Environmental management (Q2), computable general general equilibrium models (D58), Cameroon,

Does water stress, nutrient limitation, or H-toxicity explain the differential stature among Heath Forest types in Central Kalimantan, Indonesia?

To investigate the causes of the reduced stature of heath forest compared to lowland evergreen rain forest (LERF), the quantity and quality of small litterfall (LF), the standing crop of litter on the forest floor (LSC), and the annual rates of litter decay were determined over a period of 12 months in three contrasting lowland rain forest types in Central Kalimantan, Indonesia. In addition, a litterbag experiment monitored the mass loss of leaves from three dominant tree species in two heath forests (HF) of contrasting stature. Soil water and shallow groundwater dynamics in the two HFs were monitored as well. LF in the LERF was higher compared to both tall heath forest (THF) and relatively stunted heath forest (SHF), but did not differ between the two HFs. Stand-level nutrient-use efficiencies for nitrogen and phosphorus were greatest for the SHF, followed by the THF and the LERF, respectively. The observed differences in nutrient-use efficiency between the two HFs did not result in different LF totals, LSC or decomposition rates and hence cannot explain the difference in HF stature. Neither could phenolic concentrations in leaf LF, which were very similar for the two HFs. Top-soil moisture levels were consistently higher in the SHF compared to the THF and never reached wilting point in either forest type whereas shallow groundwater levels in the SHF were both closer to the surface and more persistent than in the THF. Thus, severe water stress is not thought to be a factor of importance determining HF stature. Rather, considering the much lower pH of the topsoil in the SHF compared to the THF it is hypothesized that different degrees of H-toxicity to fine roots may ultimately prove responsible for the contrast in HF stature. © 2012 Springer Science+Business Media B.V

Methods to assess tropical rain forest canopy structure: an overview

Forest canopy structure (sensu latu) is the combination of forest texture (the qualitative and quantitative composition of the vegetation as to different morphological elements), and forest structure (sensu strictu, the spatial arrangement of these elements). Scale is an aspect of major importance. At a regional scale forest types can be distinguished, like broadleaf or coniferous forest. At local scale, distribution and size and shape of tree crowns, and the spatial distribution of leaves and branches within tree crowns determine to a large extent the canopy structure. Which components and sub-components are used, and also the scale at which their spatial arrangements are studied, is of great importance for the possible outcome of the analysis of canopy structure. This is specially the case when canopy structure is needed as a correlate to ecological questions, e.g., on habitat specificity of animals, or epiphytes. Methods available for describing and analysing canopy structure are discussed. At large scale levels remote sensing data are used to describe differences in structure. High-resolution radar images are used to describe canopy structure in detail and over large areas. Repeated measurements over time can be used for monitoring purposes. Ways to measure the three dimensional structure of (components within) individual trees in detail are being developed, and are coupled to physiological models. Currently, use of such methods is only feasible for small plants. Forest tomography (where the vegetation occupation and empty spaces are determined in horizontal and vertical slices of the forest) is proposed as a way to describe vertical and horizontal structure. Vegetation cover and occupation is analysed above grid points in a forest. As an example the vertical structure of a Cameroonian forest is described at several levels of detail. The research question asked should govern completely the choice of the parameters and the methods used for the description of forest canopy structure