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81.
For many decades, protected areas (PAs) have been considered by decision makers and conservation practitioners as one of the most common policies to promote biodiversity conservation. Diverse studies have assessed the impact of conservation policies at global and regional levels by comparing deforestation rates between PAs and unprotected areas. Most of these studies are based on conventional methods and could overestimate the avoided deforestation of PAs by omitting from their analyses the lack of randomness in the allocation of forest protection.We demonstrate that estimates of effectiveness can be substantially improved by controlling for biases along dimensions that are observable and testing the sensitivity of estimates of potential hidden biases. We used matching methods to evaluate the impact on deforestation of Ecuador's tropical Andean forest protected-area system between 1990 and 2008. We found that protection reduced deforestation in approximately 6% of the protected forests. These would have been deforested had they not been protected. Conventional approaches to estimate conservation impact, which fail to control for observable covariates correlated with both protection and deforestation, substantially overestimate avoided deforestation. Our conclusions are robust to potential hidden bias, as well as to changes in modeling assumptions. In addition, it is assumed that this research will help decision-making in the framework of international climate change mitigation policies, such as REDD+. 相似文献
82.
MARIANA M. VALE§ MARIO COHN-HAFT† SCOTT BERGEN‡ STUART L. PIMM 《Conservation biology》2008,22(4):1006-1015
Abstract: Researchers predict that new infrastructure development will sharply increase the rate and extent of deforestation in the Brazilian Amazon. There are no predictions, however, of which species it will affect. We used a spatially explicit model that predicts the location of deforestation in the Brazilian Amazon by 2020 on the basis of historical patterns of deforestation following infrastructure development. We overlaid the predicted deforested areas onto maps of bird ranges to estimate the amount of habitat loss within species ranges. We also estimated the amount of habitat loss within modified ecoregions, which were used as surrogates for areas of bird endemism. We then used the extent of occurrence criterion of the World Conservation Union to predict the future conservation status of birds in the Brazilian Amazon. At current rates of development, our results show that at least 16 species will qualify as threatened or will lose more than half of their forested habitat. We also identified several subspecies and isolated populations that would also qualify as threatened. Most of the taxa we identified are not currently listed as threatened, and the majority are associated with riverine habitats, which have been largely ignored in bird conservation in Amazonia. These habitats and the species they hold will be increasingly relevant to conservation as river courses are altered and hydroelectric dams are constructed in the Brazilian Amazon. 相似文献
83.
Peter Schlesinger Carlos L. Muñoz Brenes Kelly W. Jones Lee A. Vierling 《Journal of Land Use Science》2017,12(1):36-54
Strategic planning to increase forest cover in Central American transboundary areas of the Mesoamerican Biological Corridor requires understanding land-cover and land-use change trends and drivers. We estimated forest cover change from remotely sensed land-cover and land-use classifications from 1986, 2001, and 2010, in the tri-national Trifinio Region, bordering El Salvador, Guatemala, and Honduras. Our analysis spanned subnational, national, regional, and protected border areas. We determined correlations with direct drivers of deforestation, developing a multilevel linear regression model. Higher population density significantly correlated with deforestation; coffee, agroforestry, and pasture replaced forests. The tri-national park retained forests compared to neighboring areas, but additionality requires more research. The literature on drivers suggests similar processes and factors in other tropical regions. Forest cover governance efficacy is highly variable. Results indicate relationship between governance and forest cover though more comprehensive understanding of this complex region is needed to determine their causality. 相似文献
84.
Sustainable development is a key factor for economic growth in the twenty-first century. It can be achieved in two stages, the first stage is to conserve and protect forest and other parts of the environment and the second stage is to have an appropriate economic plan to produce more agricultural and industrial goods. This investigation evaluates a possible method for sustainable development in the Sistan-Balochistan Province of Iran. Sistan-Balochistan has the lowest economic growth rate due to severe geographical and environmental constrains. 相似文献
85.
NILS KÖSTER† KAROLINE FRIEDRICH† JÜRGEN NIEDER† WILHELM BARTHLOTT† 《Conservation biology》2009,23(4):911-919
Abstract: Epiphytes are diverse and important elements of tropical forests, but as canopy‐dwelling organisms, they are highly vulnerable to deforestation. To assess the effect of deforestation on epiphyte diversity and the potential for epiphyte conservation in anthropogenically transformed habitats, we surveyed the epiphytic vegetation of an Ecuadorian cloud forest reserve and its surroundings. Our study was located on the western slopes of the Andes, a global center of biodiversity. We sampled vascular epiphytes of 110 study plots in a continuous primary forest; 14 primary forest fragments; isolated remnant trees in young, middle‐aged, and old pastures; and young and old secondary forests. It is the first study to include all relevant types of habitat transformation at a single study site and to compare epiphyte diversity at different temporal stages of fragmentation. Epiphyte diversity was highest in continuous primary forest, followed by forest fragments and isolated remnant trees, and lowest in young secondary forests. Spatial parameters of habitat transformation, such as fragment area, distance to the continuous primary forest, or distance to the forest edge from inside the forest, had no significant effect on epiphyte diversity. Hence, the influence of dispersal limitations appeared to be negligible or appeared to operate only over very short distances, whereas microclimatic edge effects acted only in the case of completely isolated trees, but not in larger forest fragments. Epiphyte diversity increased considerably with age of secondary forests, but species assemblages on isolated remnant trees were impoverished distinctly with time since isolation. Thus, isolated trees may serve for recolonization of secondary forests, but only for a relatively short time. We therefore suggest that the conservation of even small patches of primary forest within agricultural landscape matrices is essential for the long‐term maintenance of the high epiphyte diversity in tropical cloud forests. 相似文献
86.
SIMON P. DRUMMOND KERRIE A. WILSON ERIK MEIJAARD MATTHEW WATTS RONA DENNIS LENNY CHRISTY HUGH P. POSSINGHAM 《Conservation biology》2010,24(2):441-449
Abstract: Conservation efforts at local, regional, and global scales often focus on threatened species despite recent calls to adopt more equitable and potentially more economically rational approaches. Critics contend that conservation planning centered only on threatened species fails to deliver cost‐efficient conservation outcomes. We explored how planning to preserve threatened mammal species would influence the efficiency and effectiveness of conservation investments in East Kalimantan, Indonesia. We found that the explicit protection of threatened species delivered cost‐efficient outcomes in this situation, afforded adequate protection to over 90% of those species not yet considered endangered, and contributed to the partial protection of the remainder. We used Marxan, a conservation planning tool, to determine the frequency that planning units are selected in efficient reserve systems and assessed the relative risk of deforestation of each planning unit. Our methods allowed us to identify areas of the region that require the most urgent conservation action. 相似文献
87.
Belachew Gizachew Rasmus Astrup Pål Vedeld Eliakimu M. Zahabu Lalisa A. Duguma 《Natural resources forum》2017,41(2):92-104
REDD+, a climate change mitigation mechanism that values carbon in tropical forests, is expected to provide Africa with a range of environmental and socio‐economic benefits. Drawing on a vast array of literature and personal experiences, this review analyzed particular features and challenges that REDD+ implementation has faced on the continent. The distinct contexts and major challenges regarding governance, finance and technical capacities are discussed, and mechanisms to fill these gaps are suggested. Radical land tenure reform and a perfect safeguard mechanism that transfers forest land and carbon to the communities are unlikely. REDD+ should rather look for systems that respect local institutional arrangements, and allow forest‐based communities to participate in decision‐making and benefit sharing, particularly benefits from emerging REDD+. Finances for REDD+ infrastructure and the results‐based payment are in short supply. While negotiating for potential external sources in the short term, Africa should generate domestic financial resources and look for additional payments for ecosystem services. Africa should also negotiate for forest monitoring capacity building, while strengthening local community forest monitoring. This review contributes to an improved understanding of the contexts and challenges to consider in the capacity and policy development for REDD+ implementation. 相似文献
88.
Connectivity of wood thrush breeding,wintering, and migration sites based on range‐wide tracking 下载免费PDF全文
Calandra Q. Stanley Emily A. McKinnon Kevin C. Fraser Maggie P. Macpherson Garth Casbourn Lyle Friesen Peter P. Marra Colin Studds T. Brandt Ryder Nora E. Diggs Bridget J. M. Stutchbury 《Conservation biology》2015,29(1):164-174
Many migratory animals are experiencing rapid population declines, but migration data with the geographic scope and resolution to quantify the complex network of movements between breeding and nonbreeding regions are often lacking. Determining the most frequently used migration routes and nonbreeding regions for a species is critical for understanding population dynamics and making effective conservation decisions. We tracked the migration of individual Wood Thrushes (Hylocichla mustelina) (n = 102) from across their range with light‐level geolocators and, for the first time, quantified migration routes and wintering regions for distinct breeding populations. We identified regional and species‐level migratory connectivity networks for this declining songbird by combining our tracking results with range‐wide breeding abundance estimates and forest cover data. More than 50% of the species occupied the eastern wintering range (Honduras to Costa Rica), a region that includes only one‐third of all wintering habitat and that is undergoing intensive deforestation. We estimated that half of all Wood Thrushes in North America migrate south through Florida in fall, whereas in spring approximately 73% funnel northward through a narrow span along the central U.S. Gulf Coast (88–93°W). Identifying migratory networks is a critical step for conservation of songbirds and we demonstrated with Wood Thrushes how it can highlight conservation hotspots for regional populations and species as a whole. Conectividad de Sitios de Reproducción, Invierno y Migración del Zorzal con Base en Rastreo de Cobertura Amplia 相似文献
89.
Jean Pierre Temga Jean Pierre Nguetnkam Daniela Palazzini Robert Ndjouenkeu Francesco Vitali 《International Journal of Sustainable Engineering》2014,7(3):222-234
Deforestation is one of the most dramatic threats to environmental equilibrium and food safety in many regions of the world, and particularly in sub-Saharan Africa. It is enhanced by many kinds of human activities, among which is the earth brick-firing process that needs large amounts of wood for attaining and maintaining temperatures required during this process. In order to reduce deforestation, the present study investigated from different points of view the potential of crude earth to be used as building material, taking as a case study the Logone Valley located at the border between Chad and Cameroon. First, an on-site investigation was made to verify the state-of-the-art of brick production technologies and to evaluate their impact on the environment. Subsequently, morphological and geotechnical analyses on soil samples collected from different sites of the Logone Valley were carried out, to evaluate their suitability to brick production. Finally, a pilot plant for crude earthen brick production was set, particularly based on a new press designed for this purpose. 相似文献
90.
K. Embaye 《国际发展与全球生态学杂志》2013,20(4):346-355
SUMMARY The sun is the ultimate energy source of the Earth. This energy is a resource if utilised, a menace if not. Plants collect and transform radiant energy to chemical energy through photosynthesis. Part of the converted energy is used for their maintenance, while the remainder is stored as biomass. The living biomass plays a vital role in ecological processes and relationships, and provides essential services: soil and water conservation, a buffer against the adverse effects of rain, wind and sun, aesthetics, recreation, and environmental cleaning. Harvested biomass provides safe energy and materials for production of valuable products through industrial processes and household-based technologies. In the absence of vegetation, solar radiation dries soil moisture and disrupts natural processes essential for healthy ecosystem sustenance. Light-use efficiency of plants is positively correlated with rate of growth and bamboos are among the fastest growing perennial plants. This paper is not a thorough review of radiation or bamboo. The following issues are highlighted: (1) The flow of sunlight to the Earth and its usefulness as a resource if used properly and its tendency to become a nuisance if not. (2) The virtues of bamboos as light interceptors and providers of goods and services, better than many tree species. (3) The endowment of Ethiopia with large natural bamboo resources, the availability of denuded land for expansion, and the urgency for proper management, expansion and utilisation for faster socio-economic development and environmental improvement. 相似文献