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31.
This study examines the correlation between deforestation, carbon dioxide emissions and potential causal factors of land-use change within an area of 2.7 million ha in Chiapas, southern Mexico between 1975 and 1996. Digitized land-use maps and interpreted satellite images were used to quantify land-use changes. Geo-referenced databases of population and digitized maps of roads and topography were used to determine which factors could be used to explain observed changes in land-use. The study analyzed the relationship between carbon emissions during this period and two types of possible causal factors: “predisposing” factors that determine the susceptibility of a particular area of forest to change (slope, distance to agriculture and roads, land tenure) and “driving” factors representing the pressures for change (population density, poverty). The correlated factors were combined in risk matrices, which show the proportion of vulnerable carbon stocks lost in areas with defined social, economic and environmental characteristics. Such matrices could be used to predict future deforestation rates and provide a verifiable evidence-base for defining baseline carbon emissions for forest conservation projects. Based on the results of the analysis, two matrices were constructed, using population density as the single most important driving factor and distance from roads and distance from agriculture as the two alternatives for the predisposing factors of deforestation.  相似文献   
32.
Young L 《Disasters》1985,9(2):122-133
This paper attempts to examine the broad features of Somalia's harsh physical environment into which several hundreds of thousands of refugees, with mainly a nomadic or semi-nomadic life style and culture, dramatically descended six years ago. The thirty-six rural camps in which at least half of them live are described as is the refugee agricultural programme which is training several thousand families so that they may be "self-supporting." The four regions where the camps are located are each briefly summarized in terms of their soils, their climates, their natural vegetation, and the type of agriculture which the refugee farmers practice. A more detailed analysis is then given on the following critical environmental concerns: Vegetation and erosion on refugee farms, the growing problem of refugee livestock, the destruction of trees, and irrigation practices and salinity on refugee farms. The paper concludes with an argument to preserve Somalia's environment from careless and destructive exploitation, which is leading towards desertification, and calls for an in-depth study of the situation.  相似文献   
33.
ABSTRACT

Post-frontier governance in the Brazilian Amazon highlights the interaction of regulatory technologies, institutions and practices to combat illegal deforestation and appropriation of public lands. While the Amazon fires received tremendous media coverage in 2019, the dismantlement of environmental laws and regulatory agencies has supported the rise in deforestation as early as 2012. We discuss the impact of post-frontier governance in Southwest-Pará by analyzing the spatial distribution of deforestation, territorial management, law enforcement, and environmental regularization from 2000 to 2018. The integration of spatial analysis with qualitative field surveys in the blacklisted municipality Novo Progresso shows that deforestation control largely fails, specifically in undesignated public lands. While land tenure security remains the biggest challenge in the region, the persistent imagination of free-for-all frontier spaces encourages the uncontrolled appropriation of and speculation with public lands. Here, the Rural Environmental Registry (CAR) has been identified as a key instrument to secure land claims.  相似文献   
34.
Reducing Emissions from Deforestation and forest Degradation (REDD+) is a promising mechanism of payments for ecosystem services with the aim to effectively reduce emissions in an efficient and equitable manner. REDD+ is part of the Paris-agreement reached at the UNFCCC COP21 in December 2015, but questions on whether REDD+ will work and bring multi-benefits are still hotly debated. Moreover, the results and messages from research on REDD+ in different regions are mixed, context-based and fragmented. Here, we employ a survey among REDD+ stakeholders, researchers, and consultants to evaluate the opportunities and challenges of REDD+ for achieving effective, efficient and equitable outcomes and co-benefits (3E+). We substantiate our survey results with a literature review. Results suggest that the challenges in achieving the 3E+ relate to the disproportionality between deforestation drivers and mitigation measures, diverging perceptions of equity among REDD+ stakeholders, complexity of property rights, and fragile willingness of stakeholders to engage in REDD+. If these challenges can be successfully addressed by the involved stakeholder groups, they can be turned into opportunities for realizing REDD+.  相似文献   
35.
Tropical montane cloud forests (TMCF) are among the most threatened ecosystems globally in spite of their high strategic value for sustainable development due to the key role played by these forests in hydrological cycle maintenance and as reservoirs of endemic biodiversity. Resources for effective conservation and management programs are rarely sufficient, and criteria must be applied to prioritize TMCF for conservation action. This paper reports a priority analysis of the 13 main regions of TMCF distribution in Mexico, based on four criteria: (1) forest quality, (2) threats to forest permanence, (3) threats to forest integrity, and (4) opportunities for conservation. Due to the diverse socio-environmental conditions of the local communities living in Mexican TMCF regions, their associated social characteristics were also evaluated to provide a background for the planning of conservation actions. A set of indicators was defined for the measurement of each criterion. To assign priority values for subregions within each main region, an international team of 40 participants evaluated all the indicators using multicriteria decision-making analysis. This procedure enabled the identification of 15 subregions of critical priority, 17 of high priority, and 10 of medium priority; three more were not analysed due to lack of information. The evaluation revealed a number of subjects that had hitherto been undetected and that may prove useful for prioritization efforts in other regions where TMCF is similarly documented and faces equally severe threats. Based on this analysis, key recommendations are outlined to advance conservation objectives in those TMCF areas that are subjected to high pressure on forest resources.  相似文献   
36.
The industrialization of the Paraíba Valley, Brazil has been driven since the 1950s by an intense urbanization process, while municipalities located far from the valley's economic center stagnated. Despite the economic differences and unequal population distribution in the region, the municipalities share similar topographic characteristics with a predominance of hilly terrains. The depletion of the soils' productive capacity after numerous land use cycles without adequate management practices was a common cause of land use abandonment. This research analyzes land use/cover data, environmental policies, census-based data, and interviews with stakeholders, to understand the factors that account for a forest transition in the Paraíba Valley where gains in forest cover more than offset any remaining deforestation. Local conditions, such as topography, land use history, environmental policies, engagement of society in complying with legal regulations, commodity markets, and the action of enforcement agencies, represent dimensions which, combined, have boosted forest transitions.  相似文献   
37.
This article investigates whether protected areas are efficient instruments against deforestation in the Brazilian Amazônia. A Dynamic Spatial Durbin Model taking into account both the location bias and the spatial spillover effects between municipalities allows to assess the impact of the different types of protected areas (integral protected areas, sustainable protected areas and indigenous lands) on deforestation. We show that deforestation decisions are strategic complements. The econometric results differ according to the type of protected area. It is shown that: i) integral protected areas and indigenous lands allow for reducing deforestation; ii) sustainable use areas do not help to reduce deforestation; and iii) the spillover effects generated by integral protected areas and indigenous lands lead a reduction in deforestation in their vicinity. A 10% increase in the surface area of integral protected areas (indigenous lands) allows an estimated 9.32 sq. km (10.08 sq. km) of avoided deforestation.  相似文献   
38.
We integrate new challenges to thinking about resource markets and sustainable resource use policies in a general framework. The challenges, emerging from six papers that JEEM publishes in a special issue, are (i) demand uncertainty and stockpiling, (ii) international trade and resource dependence, (iii) deforestation, and (iv) intertemporal effects of climate change policies (“Green Paradox”). We discuss new insights and results on these issues by fitting them into the Hotelling model of non-renewable resource depletion.  相似文献   
39.
Deforestation in the Brazilian Amazon released approximately 5.7 billion tons of CO2 to the atmosphere between 2000 and 2010, and 50–80% of this deforestation was for pasture. Most assume that increasing demand for cattle products produced in Brazil caused this deforestation, but the empirical work to-date on cattle documents only correlations between cattle herd size, pasture expansion, cattle prices, and deforestation. This paper uses panel data on deforestation and foot-and-mouth disease (FMD) status—an exogenous demand shifter—to estimate whether changes in FMD status caused new deforestation in municipalities in the Brazilian Amazon and cerrado biomes during the 2000–2010 period. Results suggest that, on average, becoming certified as FMD-free caused a temporary spike in deforestation in the 2 years after a municipality became FMD-free, but caused subsequent deforestation to decline relative to infected municipalities during the 2000–2010 period.  相似文献   
40.
Land-cover types were analyzed for 1970, 1990 and 2000 as the bases for determining land-use systems and their influence on the resilience of tropical rain forests in the Tehuantepec Isthmus, Mexico. Deforestation (DR) and mean annual transformation rates were calculated from land-cover change data; thus, the classification of land-use change processes was determined according to their impact on resilience: a) Modification, including land-cover conservation and intensification, and b) Conversion, including disturbance and regeneration processes. Regeneration processes, from secondary vegetation under extensive use, cultivated vegetation under intensive use, and cultivated or induced vegetation under extensive use to mature or secondary vegetation, have high resilience capacity. In contrast, cattle-raising is characterized by rapid expansion, long-lasting change, and intense damages; thus, recent disturbance processes, which include the conversion to cattle-raising, provoke the downfall of the traditional agricultural system, and nullify the capacity of resilience of tropical rain forest. The land-use cover change processes reveal a) the existence of four land-use systems (forestry, extensive agriculture, extensive cattle-raising, and intensive uses) and b) a trend towards the replacement of agricultural and forestry systems by extensive cattle-raising, which was consolidated during 1990–2000 (DR of evergreen tropical rain forest=4.6%). Only the forestry system, which is not subject to deforestation, but is affected by factors such as selective timber, extraction, firewood collection, grazing, or human-induced fire, is considered to have high resilience (2 years), compared to agriculture (2–10 years) or cattle-raising (nonresilient). It is concluded that the analysis of land-use systems is essential for understanding the implications of land-use cover dynamics on forest recovery and land degradation in tropical rain forests.  相似文献   
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