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1.
Zero-deforestation commitments are a type of voluntary sustainability initiative that companies adopt to signal their intention to reduce or eliminate deforestation associated with commodities that they produce, trade, and/or sell. Because each company defines its own zero-deforestation commitment goals and implementation mechanisms, commitment content varies widely. This creates challenges for the assessment of commitment implementation or effectiveness. Here, we develop criteria to assess the potential effectiveness of zero-deforestation commitments at reducing deforestation within a company supply chain, regionally, and globally. We apply these criteria to evaluate 52 zero-deforestation commitments made by companies identified by Forest 500 as having high deforestation risk. While our assessment indicates that existing commitments converge with several criteria for effectiveness, they fall short in a few key ways. First, they cover just a small share of the global market for deforestation-risk commodities, which means that their global impact is likely to be small. Second, biome-wide implementation is only achieved in the Brazilian Amazon. Outside this region, implementation occurs mainly through certification programs, which are not adopted by all producers and lack third-party near-real time deforestation monitoring. Additionally, around half of all commitments include zero-net deforestation targets and future implementation deadlines, both of which are design elements that may reduce effectiveness. Zero-net targets allow promises of future reforestation to compensate for current forest loss, while future implementation deadlines allow for preemptive clearing. To increase the likelihood that commitments will lead to reduced deforestation across all scales, more companies should adopt zero-gross deforestation targets with immediate implementation deadlines and clear sanction-based implementation mechanisms in biomes with high risk of forest to commodity conversion.  相似文献   

2.
Soybean farming has brought economic development to parts of South America, as well as environmental hopes and concerns. A substantial hope resides in the decoupling of Brazil's agricultural sector from deforestation in the Amazon region, in which case expansive agriculture need not imply forest degradation. However, concerns have also been voiced about the potential indirect effects of agriculture. This article addresses these indirect effects for the case of the Brazilian Amazon since 2002. Our work finds that as much as thirty-two percent of deforestation, or the loss of more than 30,000 km2 of Amazon forest, is attributable, indirectly, to Brazil's soybean sector. However, we also observe that the magnitude of the indirect impact of the agriculture sector on forest loss in the Amazon has declined markedly since 2006. We also find a shift in the underlying causes of indirect land use change in the Amazon, and suggest that land appreciation in agricultural regions has supplanted farm expansions as a source of indirect land use change. Our results are broadly congruent with recent work recognizing the success of policy changes in mitigating the impact of soybean expansion on forest loss in the Amazon. However, they also caution that the soybean sector may continue to incentivize land clearings through its impact on regional land markets.  相似文献   

3.
《Climate Policy》2013,13(1):7-22
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.  相似文献   

4.
Despite recent success in reducing forest loss in the Brazilian Amazon, additional forest conservation efforts, for example, through ‘Reducing Emissions from Deforestation and Forest Degradation’ (REDD+), could significantly contribute to global climate-change mitigation. Economic incentives, such as payments for environmental services could promote conservation, but deforestation often occurs on land without crucial tenure-security prerequisites. Improving the enforcement of existing regulatory disincentives thus represents an important element of Brazil's anti-deforestation action plan. However, conservation law enforcement costs and benefits have been much less studied than for conditional payments. We develop a conceptual framework and a spatially explicit model to analyze field-based regulatory enforcement in the Brazilian Amazon. We validate our model, based on historical deforestation and enforcement mission data from 2003 to 2008. By simulating the current conservation law enforcement practice, we analyze the costs of liability establishment and legal coercion for alternative conservation targets, and evaluate corresponding income impacts. Our findings suggest that spatial patterns of both deforestation and inspection costs markedly influence enforcement patterns and their income effects. Field-based enforcement is a highly cost-effective forest conservation instrument from a regulator's point of view, but comes at high opportunity costs for land users. Payments for environmental services could compensate costs, but will increase budget outlays vis-à-vis a command-and-control dominated strategy. Both legal and institutional challenges have to be overcome to make conservation payments work at a larger scale. Decision-makers may have to innovatively combine incentive and disincentive-based policy instruments in order to make tropical forest conservation both financially viable and socially compatible.  相似文献   

5.
In response to substantial deforestation over many decades, large scale reforestation programs are being implemented across many tropical developing countries. Examples include the United Nations Billion Trees Campaign, the National Greening Program in the Philippines, and the 5 million ha reforestation program in Vietnam. However, while substantial investments are being made in reforestation, little information exists on the drivers influencing reforestation success and how these interact to determine environmental and socio-economic outcomes. In this study we surveyed 43 reforestation projects on Leyte Island, The Philippines to identify the drivers that most influence reforestation success as measured by key indicators drawn from the literature, including interactions between drivers and between drivers and indicators. We investigated 98 potential success drivers, including technical and biophysical factors; socio-economic factors; institutional, policy and management factors; and reforestation project characteristics. We also measured 12 success indicators, including forest establishment, forest growth, environmental and socio-economic success indicators. Stepwise multiple regressions were used to identify significant relationships among drivers and indicators and this analysis was used to develop a system of driver and indicator relationships. Based on this we found that revegetation method, funding source, education and awareness campaigns, the dependence of local people on forests, reforestation incentives, project objectives, forest protection mechanisms and the condition of road infrastructure were highly connected drivers that influenced multiple success indicators either directly or indirectly. We conclude that policies targeting revegetation methods, socioeconomic incentives, forest protection mechanisms, sustainable livelihoods, diversification of funding and partnerships, technical support, and infrastructure development are likely to have a broad systemic and beneficial effect on the success of reforestation programs in tropical developing countries.  相似文献   

6.
Deforestation for cattle production persists in the Brazilian Amazon despite ongoing efforts by the public and private sectors to combat it. The complexity of the cattle supply chain, which we describe in depth here, creates challenges for the landmark Zero-Deforestation Cattle Agreements in particular and for enforcement of deforestation policies in general. Here, we present a holistic analysis that is increasingly relevant as the number of policies, initiatives, and markets affecting the region increases. We provide the first property-level analysis of which ranchers decided to deforest in the last decade and identify the characteristics that are most related to deforestation. We rely on newly available animal transit and property boundary data to examine 113,000 properties in the three major cattle-producing states in the Brazilian Amazon. We consider characteristics related to a property’s role in the supply chain, location, land characteristics, and the policy environment. We find that deforestation is most likely to occur on properties that sell fewer cattle and earlier in the supply chain, are located in remote locations, and have a high percent of remaining forest. Our results can be used to improve enforcement of existing policies by targeting resources to properties and location where deforestation is more likely.  相似文献   

7.
As the world’s population continues to grow, agricultural expansion is expected to increase to meet future food demand often at the expense of other land uses. However, there are limited studies examining the degree to which forest cover will change and the underlying assumptions driving these projections. Focusing on food and forest scenarios for the middle to the end of the current century, we review 63 main scenarios and 28 global modelling studies to address variations in land use projections and evaluate the potential outcomes on forest cover. Further, their potential impacts on greenhouse gases (GHG) emission/sequestration and global temperature are explored. A majority (59%) of scenarios expected a reduction in both forests and pasturelands to make way for agricultural expansion (particularly reference and no mitigation scenarios). In most scenarios, the extent of forest loss is proportional to that of crop gain, which is associated with higher GHG emission and global temperature, loss of carbon sequestration potential and increase in soil erosion. However, 32% of scenarios predicted that meeting food security objectives is possible without leading to further deforestation if there is a global reduction in the demand for energy intensive foods, and improvements in crop yields. Forest gain and lower rates of deforestation are needed to achieve ambitious climate targets over the next decade. Our analysis also highlights carbon taxes (prices), reforestation/afforestation and bioenergy as important variables that can contribute to maintaining or increasing global forest area in the future.  相似文献   

8.
Armed conflicts trigger region-specific mechanisms that affect land use change. Deforestation is presented as one of the most common negative environmental impacts resulting from armed conflicts, with relevant consequences in terms of greenhouse gas emissions and loss of ecosystem services. However, the impact of armed conflict on forests is complex and may simultaneously lead to positive and negative environmental outcomes, i.e. forest regrowth and deforestation, in different regions even within a country. We investigate the impact that armed conflict exerted over forest dynamics at different spatial scales in Colombia and for the global tropics during the period 1992–2015. Through the analysis of its internally displaced population (departures) our results suggest that, albeit finding forest regrowth in some municipalities, the Colombian conflict predominantly exerted a negative impact on its forests. A further examination of georeferenced fighting locations in Colombia and across the globe shows that conflict areas were 8 and 4 times more likely to undergo deforestation, respectively, in the following years in relation to average deforestation rates. This study represents a municipality level, long-term spatial analysis of the diverging effects the Colombian conflict exerted over its forest dynamics over two distinct periods of increasing and decreasing conflict intensity. Moreover, it presents the first quantified estimate of conflict's negative impact on forest ecosystems across the globe. The relationship between armed conflict and land use change is of global relevance given the recent increase of armed conflicts across the world and the importance of a possible exacerbation of armed conflicts and migration as climate change impacts increase.  相似文献   

9.
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.  相似文献   

10.
The water cycle over the Amazon basin is a regulatory mechanism for regional and global climate. The atmospheric moisture evaporated from this basin represents an important source of humidity for itself and for other remote regions. The deforestation rates that this basin has experienced in the past decades have implications for regional atmospheric circulation and water vapor transport. In this study, we analyzed the changes in atmospheric moisture transport towards tropical South America during the period 1961–2010, according to two deforestation scenarios of the Amazon defined by Alves et al. (Theor Appl Climatol 100(3-4):337–350, 2017). These scenarios consider deforested areas of approximately 28% and 38% of the Amazon basin, respectively. The Dynamic Recycling Model is used to track the transport of water vapor from different sources in tropical South America and the surrounding oceans. Our results indicate that under deforestation scenarios in the Amazon basin, continental sources reduce their contributions to northern South America at an annual scale by an average of between 40 and 43% with respect to the baseline state. Our analyses suggest that these changes may be related to alterations in the regional Hadley and Walker cells. Amazon deforestation also induces a strengthening of the cross-equatorial flow that transports atmospheric moisture from the Tropical North Atlantic and the Caribbean Sea to tropical South America during the austral summer. A weakening of the cross-equatorial flow is observed during the boreal summer, reducing moisture transport from the Amazon to latitudes further north. These changes alter the patterns of precipitable water contributions to tropical South America from both continental and oceanic sources. Finally, we observed that deforestation over the Amazon basin increases the frequency of occurrence of longer dry seasons in the central-southern Amazon (by between 29 and 57%), depending on the deforestation scenario considered, as previous studies suggest.  相似文献   

11.
Production of commodities for global markets is an increasingly important factor of tropical deforestation, taking over smallholders subsistence farming. Measures to reduce deforestation and convert shifting cultivation systems towards permanent crops have recently been strengthened in several countries. But these changes have variable environmental and social impacts, including on ethnic minorities. In Vietnam, although a forest transition – i.e. shift from shrinking to expanding forest cover – occurred at the national scale, deforestation fronts and agricultural colonization for commodity crops – a.o. coffee – still dominated the Central Highlands plateaus. Previous studies suggested that the dominant land use changes in that region were on the one hand the acquisition and conversion of agricultural lands to perennial crops for external markets by capital-endowed Kinh households – the majority ethnic group in Vietnam – and on the other hand the corresponding displacement of poor households of ethnic minorities relying on shifting cultivation towards the forest margins. This study tested this hypothesis by using remote sensing to analyze land use and cover changes and deforestation trajectories in the coffee-growing area in Dak Lak and Dak Nong provinces over 2000–2010. Land use changes were linked with socioeconomic dynamics using secondary statistics and spatial modelling. Net deforestation reached ?0.31% y?1 of the total area between 2000 and 2010. Deforestation was indeed mainly directly caused by shifting cultivation for annual crops, but this was partly driven indirectly by expansion of coffee and other perennial crops over agricultural lands. Displacement of shifting cultivation into the forest margins, pushed by market crops expansion, was the spatial manifestation of the marginalization of local ethnic minorities and poor migrants, pushed by capital-endowed migrants. This marginalization is a long-standing process rooted in the colonization and development strategy for the highlands followed since colonial times. Over the late 2000s, rapid deforestation was strongly reducing the benefits of national-scale forest recovery, and might shift the country back to net losses of natural forest. Implications for policies that may affect deforestation are discussed.  相似文献   

12.
The United Nations’ Sustainable Development Goals (SDGs) are described as integrated and indivisible, where sustainability challenges must be addressed across sectors and scales to achieve global-level sustainability. However, SDG monitoring mostly focuses on tracking progress at national-levels, for each goal individually. This approach ignores local and cross-border impacts of national policies and assumes that global-level progress is the sum of national, sector-specific gains. In this study, we investigate effects of reforestation programs in China on countries supplying forest and agricultural commodities to China. Using case studies of rubber and palm oil production in Southeast Asian countries, soy production in Brazil and logging in South Pacific Island states, we investigate cross-sector effects of production for and trade to China in these exporting countries. We use a three-step multi-method approach. 1) We identify distal trade flows and the narratives used to justify them, using a telecoupling framework; 2) we design causal loop diagrams to analyse social-ecological processes of change in our case studies driven by trade to China and 3) we link these processes of change to the SDG framework. We find that sustainability progress in China from reforestation is cancelled out by the deforestation and cross-sectoral impacts supporting this reforestation abroad. Narratives of economic development support commodity production abroad through unrealised aims of benefit distribution and assumptions of substitutability of socio-ecological forest systems. Across cases, we find the analysed trade supports unambiguous progress on few SDGs only, and we find many mixed effects – where processes that support the achievement of SDGs exist, but are overshadowed by counterproductive processes. Our study represents a useful approach for tracking global-level impacts of national sustainability initiatives and provides cross-scale and cross-sectoral lenses through which to identify drivers of unsustainability that can be addressed in the design of effective sustainability policies.  相似文献   

13.
Community forest management has been identified as a win-win option for reducing deforestation while improving the welfare of rural communities in developing countries. Despite considerable investment in community forestry globally, systematic evaluations of the impact of these policies at appropriate scales are lacking. We assessed the extent to which deforestation has been avoided as a result of the Indonesian government’s community forestry scheme, Hutan Desa (Village Forest). We used annual data on deforestation rates between 2012 and 2016 from two rapidly developing islands: Sumatra and Kalimantan. The total area of Hutan Desa increased from 750 km2 in 2012 to 2500 km2 in 2016. We applied a spatial matching approach to account for biophysical variables affecting deforestation and Hutan Desa selection criteria. Performance was assessed relative to a counterfactual likelihood of deforestation in the absence of Hutan Desa tenure. We found that Hutan Desa management has successfully achieved avoided deforestation overall, but performance has been increasingly variable through time. Hutan Desa performance was influenced by anthropogenic and climatic factors, as well as land use history. Hutan Desa allocated on watershed protection forest or limited production forest typically led to a less avoided deforestation regardless of location. Conversely, Hutan Desa granted on permanent or convertible production forest had variable performance across different years and locations. The amount of rainfall during the dry season in any given year was an important climatic factor influencing performance. Extremely dry conditions during drought years pose additional challenges to Hutan Desa management, particularly on peatland, due to increased vulnerability to fire outbreaks. This study demonstrates how the performance of Hutan Desa in avoiding deforestation is fundamentally affected by biophysical and anthropogenic circumstances over time and space. Our study improves understanding on where and when the policy is most effective with respect to deforestation, and helps identify opportunities to improve policy implementation. This provides an important first step towards evaluating the overall effectiveness of this policy in achieving both social and environmental goals.  相似文献   

14.
The conversion of tropical forests to croplands and grasslands is a major threat to global biodiversity, climate and local livelihoods and ecosystems. The enforcement of protected areas as well as the clarification and strengthening of collective and individual land property rights are key instruments to curb deforestation in the tropics. However, these instruments are territorial and can displace forest loss elsewhere. We investigate the effects of protected areas and various land tenure regimes on deforestation and possible spillover effects in Bolivia, a global tropical deforestation hotspot. We use a spatial Durbin model to assess and compare the direct and indirect effects of protected areas and different land tenure forms on forest loss in Bolivia from 2010 to 2017. We find that protected areas have a strong direct effect on reducing deforestation. Protected areas – which in Bolivia are all based on co-management schemes - also protect forests in adjacent areas, showing an indirect protective spillover effect. Indigenous lands however only have direct forest protection effects. Non-indigenous collective lands and small private lands, which are associated to Andean settlers, as well as non-titled lands, show a strong positive direct effect on deforestation. At the same time, there is some evidence that non-indigenous collective lands also encourage deforestation in adjacent areas, indicating the existence of spillovers. Interestingly, areas with high poverty rate tend to be less affected by deforestation whatever tenure form. Our study stresses the need to assess more systematically the direct and indirect effects of land tenure and of territorial governance instruments on land use changes.  相似文献   

15.
F. A. Bazzaz 《Climatic change》1998,39(2-3):317-336
Tropical forest ecosystems are large stores of carbon which supply millions of people with life support requirements. Currently tropical forests are undergoing massive deforestation. Here, I address the possible impact of global change conditions, including elevated CO2, temperature rise, and nitrogen deposition on forest structure and dynamics. Tropical forests may be particularly susceptible to climate change for the following reasons: (1) Phenological events (such as flowering and fruiting) are highly tuned to climatic conditions. Thus a small change in climate can have a major impact on the forest, its biological diversity and its role in the carbon cycle. (2) There are strong coevolutionary interactions, such as pollination seed dispersal, with a high degree of specialization, i.e., only certain animals can effect these activities for certain species. Global change can decouple these tight coevolutionary interactions. (3) Because of high species diversity per unit area, species of the tropical rain forest must have narrow niches. Thus changes in global climate can eliminate species and therefore reduce biological diversity. (4) Deforestation and other forms of disturbance may have significant feedback on hydrology both regionally and globally. The predicted decline in the rainfall in the Amazon Basin and the intensification of the Indian monsoon can have a large effect on water availability and floods which are already devastating low-lying areas. It is concluded that tropical forests may be very sensitive to climate change. Under climatic change conditions their structure and function may greatly change, their integrity may be violated and their services to people may be greatly modified. Because they are large stores of great biological diversity, they require immediate study before it is too late. The study requires the collaboration of scientists with a wide range of backgrounds and experiences including biologists, climate modellers, atmospheric scientists, economists, human demographers and sociologists in order to carry out holistic and urgently needed work. Global climatic change brings a great challenge to science and to policy makers.  相似文献   

16.
In tropical Latin America, pasture land for extensive grazing continues to expand, mostly at the expense of forest cover. Until now, scientists and policy makers tackling this issue had no geographically exhaustive information at the continental level about the spatial dynamics of this process. On the basis of a land use change-modeling framework we made a projection of potential land use changes for the year 2010.The chosen modeling framework incorporates a number of essential aspects of the complexity of land use change, such as the interrelation of spatial and temporal dynamics, land use history and scale dependence. The model was provided with up-to-date, continent wide, detailed information on present land use and its location factors, selected on the basis of literature. Model inputs were established in collaboration with experts from the region.Significant statistical relations were obtained that describe land use patterns in sub-regions, giving insights into the deforestation process and its location factors. Combined with decision rules and quantitative estimates of land use change, “hot spots” of forest to pasture and crop land conversion were projected. The results envisage a predominant replacement of forest by pasture. Substantially different trends among countries are predicted, both concerning the spatial patterns of deforestation and the substitution trends between land uses. The hot spot maps also show sensitive biological areas that may be at risk.The resulting continent wide map of projected change shall help to target policy attention and measures. It also provides a context to the numerous undergoing deforestation case studies. Finally, it is proposed that the study's results be considered in the priority setting of future research on the causes of deforestation.  相似文献   

17.
This paper presents a new accounting mechanism in the context of the UNFCCC issue on reducing emissions from deforestation in developing countries, including technical options for determining baselines of forest conversions. This proposal builds on the recent scientific achievements related to the estimation of tropical deforestation rates and to the assessment of ‘intact’ forest areas. The distinction between ‘intact’ and ‘non intact’ forests used here arises from experience with satellite-based deforestation measurements and allows accounting for carbon losses from forest degradation. The proposed accounting system would use forest area conversion rates as input data. An optimal technical solution to set baselines would be to use historical average figures during the time period from 1990 to 2005. The system introduces two different schemes to account for preserved carbon: one for countries with high forest conversion rates where the desired outcome would be a reduction in their rates, and another for countries with low rates. A ‘global’ baseline rate would be used to discriminate between these two country categories (high and low rates). For the hypothetical accounting period 2013–2017 and considering 72% of the total tropical forest domain for which data are available, the scenario of a 10% reduction of the high rates and of the preservation of low rates would result in approximately 1.6 billion tCO2 of avoided emissions. The resulting benefits of this reduction would be shared between those high-rate countries which reduced deforestation and those low-rate countries which did not increase their deforestation over an agreed threshold (e.g., half of “global” baseline rate).  相似文献   

18.
Mexico is relatively advanced in its preparation for international policy on Reduced Emissions from Deforestation and forest Degradation (REDD+) and has many of the pre-conditions needed to support a community approach in the implementation of a national REDD+ programme, particularly as regards tenure of forests and experience with community forest management and PES schemes, although these conditions do not pertain everywhere. One critical issue that is yet to be resolved concerns rights to carbon credits and distribution of the financial benefits flowing from REDD+. We demonstrate that attribution of carbon credits from reduced deforestation and degradation at the community level is virtually impossible from a technical viewpoint, since these credits are counterfactual. Payments based on assessment of performance of each community in terms of such reductions would moreover be inequitable and inefficient. Flat rate payments in return for agreed improvements in management are likely to be more motivating and much easier to administer. However, increases in carbon stock (forest enhancement) can be physically measured on site, and could be more easily attributed to each individual community. We therefore propose a system in which reduced deforestation and degradation are considered environmental services, with credits accruing to national government. The financial value of the credits may be used to finance flat rate payments to communities who agree to implement improved management. On the other hand, credits for forest enhancement, which reflect measurable increases in carbon in the communities’ trees, would be considered environmental goods. These should be considered the direct property of the owners of the forest (in the same sense as wood or poles) and it would be possible for communities to sell these credits themselves. We acknowledge however that many other problems face implementation of REDD+ in Mexico, and provide a number of important examples.  相似文献   

19.
The lowlands of eastern and northeastern Bolivia are characterized by a transition between the humid evergreen forests of the Amazon Basin and the deciduous thorn-scrub vegetation of the Gran Chaco. Within this landscape lies one of the world’s best preserved areas: the ecoregion known as the Chiquitano dry forest, where deforestation patterns over a 30 year period were analyzed. Results indicate that the area of the natural cover was reduced from 97.21 % before 1976 to 82.10 % in 2008, causing significant change in the landscape, especially in the spatial configuration of forest cover. The density of forest fragments increased from 0.073 patches per 100 ha before 1976 to 0.509 in 2008, with a mean distance between patches of 151 and 210 m over the same period, leading to a considerable reduction in the fragment sizes, from 1,204 ha before 1976 to a mere 54 in 2008. This pattern, observed in forests, does not occur in the savannas because, on one hand the savanna area is much lower compared to that of forests, and on the other because the deforestation process tended to be concentrated within forested areas. Based on the observed patterns, it is possible that in the future the natural landscapes will be substituted principally by anthropic landscapes, if there is no change in the economic and land distribution policies. If this process continues, it will stimulate the expansion of mechanized agriculture and the colonization of new areas, which will lead to further deforestation and landscape fragmentation.  相似文献   

20.
Due to human activities, most natural ecosystems of the world have disappeared and the rest are threatened. At a global scale, 40% of the remaining forests occur in Indigenous Peoples Lands (IPL). While several studies show that IPL contribute to conserve forest-cover and halt forest-loss, other studies have found opposite results. The differing results on the role of IPL in forest conservation and loss are probably because of the effect of other variables, e.g. land tenure security. In this study, we addressed the role of IPL in forest conservation and loss, differentiating IPL with land-tenure security (IPL-S) and insecurity (IPL-I). We worked in a deforestation hotspot, the South American Dry Chaco region. First, we mapped IPL in the Dry Chaco. Then, covering the period 2000–2019, we measured forest cover and loss in IPL-S, IPL-I and in areas that are not Indigenous (non-IPL). Finally, we used a matching estimators method to statistically evaluate if IPL-S and IPL-I halt forest loss. To avoid bias, we accounted for the effect of variables such as Country (Argentina/Bolivia/Paraguay), Protected Area (yes/no), etc. We created the first map of IPL for the Dry Chaco, and found that at least 44% of the remaining forests are in IPL, and 67% of them are IPL-I. Our results also showed that IPL-S work as deforestation barriers. Inside PA, the effect of IPL-S was not always significant, probably because PA were already reducing forest loss. The effect of IPL-I on halting forest-loss was variable. We conclude that land-tenure security is key for IPL to reduce forest-loss, adding evidence on the importance of securing land-tenure rights of Indigenous communities for conservation purposes. At a regional scale, a large proportion of the remaining forests are Indigenous and conservation initiatives should be co-developed with locals, respecting their rights, needs and cosmovisions.  相似文献   

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