Deforestation,biomass and carbon finance in Amazonia

Biomass dynamics in Amazonia are quantified and the value that carbon finance could deliver from slowing deforestation is assessed. Above-ground forest biomass in the Legal Amazon shrank from 90 Pg to 76 Pg between 1978 and 2004. An average decrease of 0.64 Pg (standard error 0.38 Pg) per year was estimated for primary and econdary vegetation. For an improved, spatially and temporally explicit estimation, a time series of remote-sensing results and a model of secondary forest area and age distribution was combined with a large-scale forest-growth model. The observed trend of biomass decline is continuous and defines a baseline that the avoidance of deforestation could be measured against. Based on scenario calculations, the emission reductions from slightly reduced deforestation rates could be valued in the range of €1 billion annually. Carbon finance for reducing emissions from deforestation (‘avoided deforestation’), which is being discussed as an additional mechanism under the UN Framework Convention on Climate Change and its Kyoto Protocol, has the potential to alter the economic logic driving forest conversion.     

Population and poverty in Jamaican deforestation: Integrating satellite and household census data

This study uses MSS data to derive sub-national level deforestation rates at the constituency administrative level for Jamaica for 1987 and 1992. It then investigates the role of poverty and population in driving forest loss during this period by linking these estimates in a GIS with constituency level demographic and socioeconomic census data for the island. OLS regression results support the importance of population pressures and poverty in driving the destruction of Jamaica's forests and the relative contribution to deforestation of their various measures are noted and discussed. In addition to providing information on Jamaica's deforestation attributes, the study demonstrates how remotely sensed data can be used in conjunction with household census data to derive information on human-forest interactions at the sub-national level. A small simulation experiment based on regression results using key variables suggests that under any scenario, the impacts of key social and demographic changes on Jamaica's remaining forest cover may be substantial by the year 2010. This revised version was published online in July 2006 with corrections to the Cover Date.     

Enforcement and inequality in collective PES to reduce tropical deforestation: Effectiveness,efficiency and equity implications

Collective Payments for Ecosystem Services (PES), where forest users receive compensation conditional on group rather than individual performance, are an increasingly used policy instrument to reduce tropical deforestation. However, implementing effective, (cost) efficient and equitable (3E) collective PES is challenging because individuals have an incentive to free ride on others’ conservation actions. Few comparative studies exist on how different enforcement strategies can improve collective PES performance. We conducted a framed field experiment in Brazil, Indonesia and Peru to evaluate how three different strategies to contain the local free-rider problem perform in terms of the 3Es: (i) Public monitoring of individual deforestation, (ii) internal, peer-to-peer sanctions (Community enforcement) and (iii) external sanctions (Government enforcement). We also examined how inequality in wealth, framed as differences in deforestation capacity, affects policy performance. We find that introducing individual level sanctions can improve the effectiveness, efficiency and equity of collective PES, but there is no silver bullet that consistently improves all 3Es across country sites. Public monitoring reduced deforestation and improved the equity of the program in sites with stronger history of collective action. External sanctions provided the strongest and most robust improvement in the 3Es. While internal, peer enforcement can significantly reduce free riding, it does not improve the program’s efficiency, and thus participants’ earnings. The sanctioning mechanisms failed to systematically improve the equitable distribution of benefits due to the ineffectiveness of punishments to target the largest free-riders. Inequality in wealth increased group deforestation and reduced the efficiency of Community enforcement in Indonesia but had no effect in the other two country sites. Factors explaining differences across country sites include the history of collective action and land tenure systems.     

Tourism and deforestation in the Mt Everest region of Nepal

Over the past 50 years the Sherpa-inhabited Mt Everest region of Nepal has become a premier international mountaineering and trekking destination. Tourism development has brought prosperity to many Sherpas. It has also, however, had adverse impacts on regional forests and alpine vegetation because of the use of firewood by camping groups and inns and the felling of trees to construct inns and other tourist facilities. Concern that tourism was causing widespread deforestation helped catalyse the 1976 establishment of an inhabited protected area, Sagarmatha (Mt Everest) National Park, in the Khumbu region and spurred the implementation of a series of forest conservation and alternative energy development measures both within the national park and in a recently declared buffer zone in the adjacent Pharak region. This paper examines the changing pressures that tourism has placed on regional forests and alpine vegetation over the past half century and their role in regional vegetation change. This analysis is based primarily on detailed accounts of past and present forest use and change obtained during fieldwork conducted in all Khumbu and Pharak villages, along with corroborating evidence from early foreign visitors' accounts and photographs. Contrary to some early reports it now appears there has actually been little deforestation since 1950. The continuing use of firewood by inns, however, has contributed to the thinning of forests in some parts of the national park and to the depletion of shrub juniper in the most heavily visited alpine regions. There has been a greater impact on forests just outside the national park, which have been heavily thinned over an extensive area in order to provide timber to build inns within the national park.     

Accessibility and land-use patterns at the forest fringe in the northeastern part of the Philippines

Accessibility is considered to be one of the most important determinants of use and land-cover change. In rural land-use change studies, the accessibility situation is often described by simple measures of the distance to a location of interest. In this paper, different measures of access are tested for a rural area at the forest fringe in the northeastern Philippines. The accessibility measures addressed range from simple distance measures to land-use type specific transport costs and a population potential measure. The different measures are tested based on their capacity to explain the spatial pattern of different land-use types. A comparison of the findings based on a spatial analysis and an analysis of household level data is made. It is concluded that the relation between land use and accessibility is dependent on the specific characteristics of the different land-use types. The (dis-)advantages of the use of the different accessibility measures are discussed.     

基于三种WRF陆面过程方案的东南亚毁林增温响应研究

选取东南亚中南半岛地区作为模拟区域,基于高分辨率的遥感观测森林变化数据和WRF数值模式,设计毁林前后的两种情景对旱季气候进行模拟,评估NoahMP、CLM和Noah mosaic三种陆面过程方案对热带毁林增温响应的模拟能力。结果表明,CLM方案在模拟历史气温中有着更好的表现,Noah mosaic方案的结果存在明显低估。然而,对比毁林前后两种情景的模拟结果,本文发现,只有采用了"次格网"方式的Noah mosaic方案较好地模拟出毁林增温响应特征。在格网尺度采用"主导类型"计算方式的NoahMP方案没有合理地呈现出森林损失对区域气候的影响。理论上,CLM模式在计算中同时考虑格网内所有植被类型,然而本文发现CLM方案在主导类型不变的格网对森林损失比例不敏感,而且对毁林反馈的模拟结果与NoahMP方案的结果更接近。据此推测,在WRF模式耦合CLM方案的过程中,格网内参数处理方式可能产生了错误,实际采用的是"主导类型"方式。在模拟土地覆盖类型变化对气候的影响时,本文推荐使用Noah mosaic方案。同时,建议在未来版本的WRF模型中修正目前耦合的CLM方案关于次格网方法的处理方式,提供更合理的水热通量模拟。     

Stability and change within indigenous land use in the Ecuadorian Amazon

In the Amazon basin and other tropical forest regions, many forested landscapes are inhabited by indigenous peoples who are increasingly exposed to infrastructure expansion, large-scale natural resource extraction, and development programs. How indigenous land use evolves in this context will be a critical determinant of the future of these forests. To date, few studies have had access to longitudinal, large-sample and field-based data that enables the measurement of indigenous land use change and its correlates in these contexts. To address this lacuna, we make use of a unique multi-ethnic household survey conducted in 32 indigenous communities of the Northern Ecuadorian Amazon in 2001 and again with the same households in 2012. We analyze these data to measure land use and land use change as well as their determinants. This reveals that the overall household agropastoral footprint has remained close to constant over time, but with important changes within particular land uses and ethnicities. Notably, cacao has largely replaced coffee (tracking commodity price changes), and Kichwa and Shuar households have intensified production on increasingly subdivided plots, with the Shuar specializing in cattle. In contrast, Waorani and Cofán households have maintained small footprints, while Secoya households largely abandoned cattle ranching. Taken together, the results emphasize ethnic heterogeneity in indigenous land use change, a pattern which is only visible through the use of a longitudinal, large-sample, field-based design.     

Land use change effects on catchment streamflow response in a humid tropical montane cloud forest region,central Veracruz,Mexico

Tropical montane cloud forests (TMCF) are recognized for their capacity to maintain high dry-season baseflow and a host of other ecosystem services. Substantial areas of TMCF have been converted to pasture and crops such as coffee, while in other areas TCMF are recovering. However, little is known about the effects of this complex dynamic on catchment hydrology. We investigated the effect of land use on rainfall-runoff response in five neighbouring headwater micro-catchments in central Veracruz, Mexico, dominated by either mature TMCF (MF), young (20 year-old) and intermediate (40 year-old) naturally regenerating TMCF (YF and IF, respectively), shaded coffee (SC), and an intensively grazed pasture (IP). We used a 4-year record of high-resolution rainfall and streamflow (10 min) data collected from 2015 to 2019. These data were analysed via comparison of hydrologic metrics that summarize streamflow responses at various time scales and magnitudes. Results showed no statistical difference in the regulation capacity of high flows in the micro-catchment with 20 years of natural regeneration, compared to the MF. In terms of baseflow sustenance, our results support the hypothesis that MF and IF better promote this hydrologic service than the other land uses. SC exhibited a high capacity to modulate peak flows comparable to that of MF, and an intermediate capacity to sustain baseflow, suggesting that the integrated functioning of this micro-catchment was largely preserved. Finally, 40 years of intense pasture management was found to have degraded the soil hydraulic properties of IP; mainly, reducing its infiltration capacity, causing a fivefold greater peak flow response and a lower baseflow compared to MF.     

Spillover effect offsets the conservation effort in the Amazon

Diverse conservation efforts have been expanding around the globe, even under the stress of increasing agricultural production. A striking example is the supply-chain agreements put upon the Amazon forest which had reduced deforestation by 80% from the early 2000s (27,772 km²) to 2015 (6207 km²). However, evaluation of these conservation efforts usually focused on the impacts within the Amazon biome only, while the effects that spill over to other areas (e.g., displacement of environmental pressure from one area to another) were rarely considered. Ignoring spillover effects may lead to biased or even wrong conclusions about the effectiveness of these conservation efforts because the hidden cost outside the target area of conservation may offset the achievement within it. It is thus important to assess the spillover effects of these supply-chain agreements. In this study, we used the two supply-chain agreements (i.e., Soy Moratorium and zero-deforestation beef agreement) implemented in the Amazon biome as examples and evaluated their spillover effects to the Cerrado. To achieve a holistic evaluation of the spillover effects, we adopted the telecoupling framework in our analysis. The application of the telecoupling framework includes the interactions between distant systems and extends the analytical boundaries beyond the signatory areas, which fill the gap of previous studies. Our results indicate that the supply-chain agreements have significantly reduced deforestation by half compared to projections within the sending system (i.e., Pará State in the Amazon, which exports soybeans and other agricultural products), but at the cost of increasing deforestation in the spillover system (i.e., a 6.6 time increase in Tocantins State of the Cerrado, where deforestation was affected by interactions between the Amazon and other places). Our study emphasizes that spillover effects should be considered in the evaluation and planning of conservation efforts, for which the telecoupling framework works as a useful tool to do that systematically.