43 research outputs found

    Predicting aboveground forest biomass with topographic variables in human-impacted tropical dry forest landscapes

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    Topographic variables such as slope and elevation partially explain spatial variations in aboveground biomass (AGB) within landscapes. Human activities that impact vegetation, such as cattle grazing and shifting cultivation, often follow topographic features and also play a key role in determining AGB patterns, although these effects may be moderated by accessibility. In this study, we evaluated the potential to predict AGB in a rural landscape, using a set of topographical variables in combination with indicators of accessibility. We modeled linear and non-linear relationships between AGB, topographic variables within the territorial boundaries of six rural communities, and distance to roads. Linear models showed that elevation, slope, topographic wetness index, and tangential curvature could explain up to 21% of AGB. Non-linear models found threshold values for the relationship between AGB and diffuse insolation, topographic position index at 19 × 19 pixels scale and differentiated between groups of communities, improving AGB predictions to 33%. We also found a continuous and positive effect on AGB with increased distance from roads, but also a piecewise relationship that improves the understanding of intensity of human activities. These findings could enable AGB baselines to be constructed at landscape level using freely available data from topographic maps. Such baselines may be of use in national programs under the international policy Reducing Emissions from Deforestation and Forest Degradation

    Coverage of high biomass forests by the ESA BIOMASS mission under defense restrictions

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    The magnitude of the global terrestrial carbon pool and related fluxes to and from the atmosphere are still poorly known. The European Space Agency P-band radar BIOMASS mission will help to reduce this uncertainty by providing unprecedented information on the distribution of forest above-ground biomass (AGB), particularly in the tropics where the gaps are greatest and knowledge is most needed. Mission selection was made in full knowledge of coverage restrictions over Europe, North and Central America imposed by the US Department of Defense Space Objects Tracking Radar (SOTR) stations. Under these restrictions, only 3% of AGB carbon stock coverage is lost in the tropical forest biome, with this biome representing 66% of global AGB carbon stocks in 2005. The loss is more significant in the temperate (72%), boreal (37%) and subtropical (29%) biomes, with these accounting for approximately 12%, 15% and 7%, respectively, of the global forest AGB carbon stocks. In terms of global carbon cycle modelling, there is minimal impact in areas of high AGB density, since mainly lower biomass forests in cooler climates are affected. In addition, most areas affected by the SOTR stations are located in industrialized countries with well-developed national forest inventories, so that extensive information on AGB is already available. Hence the main scientific objectives of the BIOMASS mission are not seriously compromised. Furthermore, several space sensors that can estimate AGB in lower biomass forests are in orbit or planned for launch between now and the launch of BIOMASS in 2021, which will help to fill the gaps in mission coverage

    Biodiversity Loss in Latin American Coffee Landscapes: Review of the Evidence on Ants, Birds, and Trees

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    Studies have documented biodiversity losses due to intensification of coffee management (reduction in canopy richness and complexity). Nevertheless, questions remain regarding relative sensitivity of different taxa, habitat specialists, and functional groups, and whether implications for biodiversity conservation vary across regions. We quantitatively reviewed data from ant, bird, and tree biodiversity studies in coffee agroecosystems to address the following questions: Does species richness decline with intensification or with individual vegetation characteristics? Are there significant losses of species richness in coffee-management systems compared with forests? Is species loss greater for forest species or for particular functional groups? and Are ants or birds more strongly affected by intensification? Across studies, ant and bird richness declined with management intensification and with changes in vegetation. Species richness of all ants and birds and of forest ant and bird species was lower in most coffee agroecosystems than in forests, but rustic coffee (grown under native forest canopies) had equal or greater ant and bird richness than nearby forests. Sun coffee (grown without canopy trees) sustained the highest species losses, and species loss of forest ant, bird, and tree species increased with management intensity. Losses of ant and bird species were similar, although losses of forest ants were more drastic in rustic coffee. Richness of migratory birds and of birds that forage across vegetation strata was less affected by intensification than richness of resident, canopy, and understory bird species. Rustic farms protected more species than other coffee systems, and loss of species depended greatly on habitat specialization and functional traits. We recommend that forest be protected, rustic coffee be promoted, and intensive coffee farms be restored by augmenting native tree density and richness and allowing growth of epiphytes. We also recommend that future research focus on potential trade-offs between biodiversity conservation and farmer livelihoods stemming from coffee production.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74576/1/j.1523-1739.2008.01029.x.pd

    Mexico environmental services project

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    Metadata only recordThe Mexico Environmental Services Project aims to improve water quality, biodiversity, and carbon sequestration from areas with globally significant biodiversity. Eight pilot sites will be chosen to overlap with existing high-priority biodiversity conservation areas. The project objectives will be met through "(i) strengthening the capacity of CONAFOR, INE, community associations, and NGOs to increase flexibility and improve efficiency of existing service provision to support long-term development of the PSAH program in Mexico; (ii) establishing sustainable long-term financing mechanisms including an endowment fund for biodiversity conservation; (iii) establishing legal, institutional, and financial arrangements to pilot market-based mechanisms for payment for environmental services, (iv) documenting links between land use changes, water services improvements, and biodiversity conservation, and (v) defining good practices to replicate, scale up, and sustain programs based on PES markets." (excerpt from Project Executive Summary)PES-1 (Payments for Environmental Services Associate Award

    Examples from Costa Rica, Mexico, and Ecuador

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    Mexico, Costa Rica, and Ecuador have substantial experience with implementing payments for ecosystem services (PES) and conservation incentive programs. Yet, many aspects of their experiences remain poorly understood and will require special attention in any new or expanded use of these types of incentives. As these countries, along with many others, get ready to implement integrated approaches to Reduced Emissions from Deforestation and Forest Degradation (REDD or REDD+), they seek to understand how the lessons and challenges from their past experiences, as well as the wider lessons from similar initiatives around the world, can inform their emerging REDD+ strategies, policies, institutional frameworks, and tools. This report describes examples of how each of these topics has been tackled in national programs and how these experiences can inform the development of REDD+ in the three focus countries and beyond
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