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91.
Management‐effectiveness scores are used widely by donors and implementers of conservation projects to prioritize, track, and evaluate investments in protected areas. However, there is little evidence that these scores actually reflect the capacity of protected areas to deliver conservation outcomes. We examined the relation between indicators of management effectiveness in protected areas and the effectiveness of protected areas in reducing fire occurrence in the Amazon rainforest. We used data collected with the Management Effectiveness Tracking Tool (METT) scorecard, adopted by some of the world's largest conservation organizations to track management characteristics believed to be crucial for protected‐area effectiveness. We used the occurrence of forest fires from 2000 through 2010 as a measure of the effect of protected areas on undesired land‐cover change in the Amazon basin. We used matching to compare the estimated effect of protected areas with low versus high METT scores on fire occurrence. We also estimated effects of individual protected areas on fire occurrence and explored the relation between these effects and METT scores. The relations between METT scores and effects of protected areas on fire occurrence were weak. Protected areas with higher METT scores in 2005 did not seem to have performed better than protected areas with lower METT scores at reducing fire occurrence over the last 10 years. Further research into the relations between management‐effectiveness indicators and conservation outcomes in protected areas seems necessary, and our results show that the careful application of matching methods can be a suitable method for that purpose. Vinculación de Indicadores de Efectividad de Manejo con los Efectos Observados de la Ocurrencia de Fuego en Áreas Protegidas en la Amazonia  相似文献   
92.
Jamaica is a small island that is losing its forest cover at a rapid rate. Due to the dependency of its largely poor population on the many services and functions its forests provide, this loss threatens to have substantial socioeconomic and ecological consequences for the country. Despite these basic facts, the problem of Jamaican deforestation has received very little attention from the scientific community. This article presents results of an island-wide, satellite-based study of forest change for Jamaica for the period 1987–1992, which was supplemented by a field trip to the island in 1999 to assess the overall accuracy of the estimate. Landsat MSS images, which are available only up until 1992, have proved to be an invaluable and cost-effective resource for mapping forest change in the tropics, particularly in large areas. A supervised classification indicates that Jamaica experienced an average annual deforestation rate of 3.9% for this period, a figure higher than existing estimates based on partial ground surveys but lower than the FAO's 1990 Tropical Forest Assessment of 5.3% for 1981–1990. Deforestation estimates for Jamaica's 14 parishes are also presented, based on the integration of satellite-derived forest classification maps with a parish administrative boundaries map of the island in a GIS. A correlation analysis between parish deforestation estimates and socioeconomic and land use/quality indicators derived from official sources suggests that deforestation is occurring most rapidly in highly populated areas possessing large numbers of small farmers who live and work under resource-poor conditions. By providing a sense of the magnitude of and main forest loss hotspots, it is hoped that these national and subnational level forest estimates will draw scientific attention to the problem of deforestation on the island. In addition, the socioeconomic analysis may provide policy-makers and planners with some sense of the relative contribution of underlying driving process in this deforestation as a first step toward the creation of effective social programs to combat the problem.  相似文献   
93.
ABSTRACT

Between 1992 and 2015 Argentina lost 17% of its tree cover. Regionally, deforestation continues, but net forest loss recently came to a halt. Some scholars argue that this was facilitated by industrial agricultural intensification. This view is debated, but we focus on the neglected costs associated with this intensification. An almost tenfold increase of pesticide use in Argentina during the last two decades caused the pollution of soil, water and sediments. The widespread use of pesticides is impairing the health of agricultural workers and people living near agricultural fields, and is putting the health of vulnerable parts of the population (children and pregnant women) at risk. More than 50 pesticide active ingredients marketed in Argentina have been banned in the European Union for safety reasons. We contend that health and pollution aspects need to be taken into account when assessing the benefits and drawbacks of different types of land use.  相似文献   
94.
Rural communities in sub‐Saharan Africa rely upon provisioning ecosystem services (ES) to support their livelihoods, yet in areas where rapid land use change is occurring the relationship between environmental change, provisioning ES availability and livelihoods is not fully understood. This relationship is explored here within a typical rural miombo woodland landscape in south‐west Tanzania, which is undergoing rapid land use change due to expanding tobacco cultivation. The types of provisioning ES used, who uses them, changes in their availability, and the possible future impacts of these changes were explored using a mixed‐method approach. Our findings identify 19 provisioning ES used by households regardless of economic status. Firewood, building materials, and fresh water are used by almost all households, and these are perceived to be declining in availability. Households identified this as a negative environmental impact of land use change and that provisioning ES loss would be ‘bad’ for their households. Given the multi‐purpose nature of miombo woodlands, an adaptive co‐management approach, which can achieve multiple objectives through encouraging participation, learning, and empowerment of local communities, could be an appropriate strategy to achieve sustainable land use management and maintain the provision of ES within miombo woodland landscapes of sub‐Saharan Africa.  相似文献   
95.
Abstract:  We evaluated the importance of small (<5 ha) forest patches for the conservation of regional plant diversity in the tropical rainforest of Los Tuxtlas, Mexico. We analyzed the density of plant species (number of species per 0.1 ha) in 45 forest patches of different sizes (1–700 ha) in 3 landscapes with different deforestation levels (4, 11, and 24% forest cover). Most of the 364 species sampled (360 species, 99%) were native to the region, and only 4 (1%) were human-introduced species. Species density in the smallest patches was high and variable; the highest (84 species) and lowest (23 species) number of species were recorded in patches of up to 1.8 ha. Despite the small size of these patches, they contained diverse communities of native plants, including endangered and economically important species. The relationship between species density and area was significantly different among the landscapes, with a significant positive slope only in the landscape with the highest deforestation level. This indicates that species density in a patch of a given size may vary among landscapes that have different deforestation levels. Therefore, the conservation value of a patch depends on the total forest cover remaining in the landscape. Our findings revealed, however, that a great portion of regional plant diversity was located in very small forest patches (<5 ha), most of the species were restricted to only a few patches (41% of the species sampled were distributed in only 1–2 patches, and almost 70% were distributed in 5 patches) and each landscape conserved a unique plant assemblage. The conservation and restoration of small patches is therefore necessary to effectively preserve the plant diversity of this strongly deforested and unique Neotropical region.  相似文献   
96.
The forests of Colombia are influenced by the actions of armed groups and, in many cases, their settlers are economically dependent on illicit crops. Up to the present armed conflict has simultaneously discouraged organized exploitation in some frontier areas, and encouraged unsustainable use of natural resources therein. The Colombian government seeks to end the conflict by pursuing peace negotiations, and to eradicate illicit crops. How will these policies affect the forests? The environmental consequences of these policies are not only dependent on the unlikely economic success of alternative development, but on making informed decisions about infrastructure development in affected areas.  相似文献   
97.
There is a growing need to assess and monitor forest cover and its conservation status over global scales to determine human impact on ecosystems and to develop sustainability plans. Recent approaches to measure regional and global forest status and dynamics are based on remotely sensed estimates of tree cover. We argue that tree cover should not be used to assess the area of forest ecosystems because tree cover is an undefined subset of forest cover. For example, tree cover can indicate a positive trend even in the presence of deforestation, as in the case of plantations. We believe a global map of forest naturalness that accounts for the bio-ecological integrity of forest ecosystems, for example, intact forests, old-growth forest patches, rewilding forests (exploited forest landscapes undergoing long-term natural succession), and managed forests is needed for global forest assessment.  相似文献   
98.
Forest conversion is one of the greatest global threats to biodiversity, and land-use change and subsequent biodiversity declines sometimes occur over a variety of underlying geologies. However, how forest conversion and underlying geology interact to alter biodiversity is underappreciated, although spatial variability in geology is considered an integral part of sustaining ecosystems. We aimed to examine the effects of forest conversion to farmland, the underlying geology, and their interaction on the stream fishes’ diversity, evenness, and abundance in northeastern Japan. We disentangled complex pathways between abiotic and biotic factors with structural equation modeling. Species diversity of stream fishes was indirectly shaped by the interaction of land use and underlying geology. Diversity declined due to nutrient enrichment associated with farmlands, which was mainly the result of changes in evenness rather than by changes in species richness. This impact was strongest in streams with volcanic geology with coarse substrates probably because of the differential responses of abundant stream fishes to nutrient enrichment (i.e., dominance) and the high dependency of these fishes on large streambed materials during their life cycles. Our findings suggest that remediation of deforested or degraded forest landscapes would be more efficient if the interaction between land use and underlying geology was considered. For example, the negative impacts of farmland on evenness were larger in streams with volcanic geology than in other stream types, suggesting that riparian forest restoration along such streams would efficiently provide restoration benefits to stream fishes. Our results also suggest that land clearing around such streams should be avoided to conserve species evenness of stream fishes.  相似文献   
99.
Trade‐offs in ecosystem services (ES) have received increasing attention because provisioning services often come at the expense of biodiversity loss. When land‐use patterns are not maximally efficient relative to productivity, provisioning services, such as crop production, can often be increased without losing biodiversity. The Atlantic Forest (AF) encompasses dense, mixed, and seasonal forests and has high levels of endemism and anthropogenic threat. We examined trade‐offs between biodiversity and crop production in the AF to provide insights into land‐use management decisions. We developed a biodiversity metric that combines information on tree species richness, evolutionary distinctiveness, and rarity at the local level. We examined the extent to which the nature of ES trade‐offs differ among the 3 forest types. We assessed how annual deforestation rates and land management practices affect biodiversity and agricultural revenues. Finally, we tested whether it is possible to achieve the same total regional revenue without reducing biodiversity by improving local management practices. The 3 forest types had similar patterns in ES trade‐offs, although within mixed forest patterns differed. Biodiversity appeared to be more sensitive to land‐use change than crop revenues. Certain crops yielded up to 10 times higher values in some sites. Enhanced crop productivity may increase revenues without reducing biodiversity. Our results showed that to enhance human well‐being without further conversion of AF, maximizing crop productivity is needed . Increasing efficiency of management outcomes by maintaining higher biodiversity and increasing provisioning services depends on knowledge of forest type, the comparative advantage of planting crops in the best places, and preserving species in a balanced manner across forests.  相似文献   
100.
We examined the links between the science and policy of habitat corridors to better understand how corridors can be implemented effectively. As a case study, we focused on a suite of landscape‐scale connectivity plans in tropical and subtropical Asia (Malaysia, Singapore, and Bhutan). The process of corridor designation may be more efficient if the scientific determination of optimal corridor locations and arrangement is synchronized in time with political buy‐in and establishment of policies to create corridors. Land tenure and the intactness of existing habitat in the region are also important to consider because optimal connectivity strategies may be very different if there are few, versus many, political jurisdictions (including commercial and traditional land tenures) and intact versus degraded habitat between patches. Novel financing mechanisms for corridors include bed taxes, payments for ecosystem services, and strategic forest certifications. Gaps in knowledge of effective corridor design include an understanding of how corridors, particularly those managed by local communities, can be protected from degradation and unsustainable hunting. There is a critical need for quantitative, data‐driven models that can be used to prioritize potential corridors or multicorridor networks based on their relative contributions to long‐term metacommunity persistence.  相似文献   
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