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51.
Pyromancy: Reading Stories in the Flames   总被引:1,自引:0,他引:1  
Abstract:  A consensus history of fire in the United States has emerged over the past decade. It correctly identifies fire suppression's liabilities, while probably over-enthusing about fire-science capabilities. What it lacks, however, is a context of the subject's larger, braided narratives. There is, first, the grand story of fire on Earth. Quite apart from active suppression, open fire is disappearing in competition with industrial combustion. Second, there is the peculiar narrative of the public lands, the prime domain for wildland fires. These lands, and the institutions for their management, are rapidly changing. They began as "imperial" institutions, but now are devolving, privatizing, and otherwise decolonizing. Fire will change with those reforms. Third, there is a national narrative, currently obsessed with the collision of the wild and the exurban. This will probably pass within 5–6 years. Finally, there is the evolving narrative of how we imagine fire. We need a truly biological theory of fire, one in which we can flourish as unique fire creatures.  相似文献   
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Abstract: Networks of sites of high importance for conservation of biological diversity are a cornerstone of current conservation strategies but are fixed in space and time. As climate change progresses, substantial shifts in species’ ranges may transform the ecological community that can be supported at a given site. Thus, some species in an existing network may not be protected in the future or may be protected only if they can move to sites that in future provide suitable conditions. We developed an approach to determine appropriate climate‐change adaptation strategies for individual sites within a network that was based on projections of future changes in the relative proportions of emigrants (species for which a site becomes climatically unsuitable), colonists (species for which a site becomes climatically suitable), and persistent species (species able to remain within a site despite the climatic change). Our approach also identifies key regions where additions to a network could enhance its future effectiveness. Using the sub‐Saharan African Important Bird Area (IBA) network as a case study, we found that appropriate conservation strategies for individual sites varied widely across sub‐Saharan Africa, and key regions where new sites could help increase network robustness varied in space and time. Although these results highlight the potential difficulties within any planning framework that seeks to address climate‐change adaptation needs, they demonstrate that such planning frameworks are necessary, if current conservation strategies are to be adapted effectively, and feasible, if applied judiciously.  相似文献   
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Abstract: To examine differences in land use and environmental impacts between colonist and indigenous populations in the northern Ecuadorian Amazon, we combined data from household surveys and remotely sensed imagery that was collected from 778 colonist households in 64 colonization sectors, and 499 households from five indigenous groups in 36 communities. Overall, measures of deforestation and forest fragmentation were significantly greater for colonists than indigenous peoples. On average, colonist households had approximately double the area in agriculture and cash crops and 5.5 times the area in pasture as indigenous households. Nevertheless, substantial variation in land‐use patterns existed among the five indigenous groups in measures such as cattle ownership and use of hired agricultural labor. These findings support the potential conservation value of indigenous lands while cautioning against uniform policies that homogenize indigenous ethnic groups.  相似文献   
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Private‐sector financial and legal transactions have long been used to protect terrestrial habitats and working landscapes, but less commonly to address critical threats in marine environments. Transferrable and marketable fishing privileges, including permits and quotas, make it possible to use private‐sector transactions as conservation strategies to address some fishery management issues. Abating the effects of bottom trawling on the seafloor and bycatch and discard associated with the practice has proven challenging. On the Central Coast of California, The Nature Conservancy (TNC), Environmental Defense Fund, local fishers and local, state, and federal authorities worked collaboratively to protect large areas of the seafloor from bottom trawling for groundfish while addressing economic impacts of trawl closures. Contingent on the adoption of trawl‐closure areas by a federal regulatory agency, TNC used private funds to purchase federal groundfish trawl permits and vessels from willing sellers. Trawl‐closure areas were designed collaboratively by combining regional biological diversity and fisheries data with local fishers’ knowledge. The private transactional strategy was designed to remedy some deficiencies in previous federal buyouts, to mitigate economic impacts from trawl closures, and to carefully align with a public regulatory process to protect “essential fish habitat” under the Magnuson‐Stevens Fishery Conservation and Management Act. This collaborative effort protected 1.5 million ha (3.8 million acres) of seafloor, reduced trawl effort in the area by 50%, and set a precedent for collaborative partnerships between conservation and fishing interests. This is the first time a large conservation organization has taken an ownership position in a fishery and demonstrates how nongovernmental organizations can invest in fisheries to improve environmental and economic performance. Un Método Transaccional y Colaborativo para Reducir los Efectos de la Pesca de Arrastre de Fondo  相似文献   
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Abstract:  Rattan, Old World climbing palm, is an extremely valuable nontimber forest product whose canes are gathered for both market and nonmarket uses. I evaluated the effects of harvesting commercial rattan, Calamus zollingeri Becc., on genet survival and ramet demography in two primary forest sites near Lore Lindu National Park in Sulawesi, Indonesia. I monitored 168 permanently marked C. zollingeri genets for 4 years and surveyed random transects for C. zollingeri genet and ramet populations and evidence of cane harvesting in 1996 and 2000. Cane harvesting had no significant effect on genet survival or mean ramet densities. However, current cane extraction rates significantly reduced mean cane lengths and total available cane throughout the area during the study period. Based on observed genet and ramet populations and average cane growth rates of 1.4 m/year, the sustained-yield harvesting potential of C. zollingeri is approximately 101 m and 56 m/ha/year in the two study sites. Although C. zollingeri exhibits life-history traits well suited to sustained-yield harvesting, including production of multiple canes, cane resprouting following harvest, rapid cane growth, and widespread abundance below 1100 m, current harvest rates exceed growth and yield, and supplies of cane are being depleted. Rattan harvesting is widespread in Lore Lindu National Park. Approximately 18% of the park (42,000 ha) is likely subject to intensive and unsustainable extraction of C. zollingeri.  相似文献   
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Abstract:  Customary forms of resource management, such as taboos, have received considerable attention as a potential basis for conservation initiatives in the Indo-Pacific. Yet little is known about how socioeconomic factors influence the ability of communities to use customary management practices and whether socioeconomic transformations within communities will weaken conservation initiatives with a customary foundation. We used a comparative approach to examine how socioeconomic factors may influence whether communities use customary fisheries management in Papua New Guinea. We examined levels of material wealth (modernization), dependence on marine resources, population, and distance to market in 15 coastal communities. We compared these socioeconomic conditions in 5 communities that used a customary method of closing their fishing ground with 10 communities that did not use this type of management. There were apparent threshold levels of dependence on marine resources, modernization, distance to markets (<16.5 km), and population (>600 people) beyond which communities did not use customary fisheries closures. Nevertheless, economic inequality, rather than mean modernization levels seemed to influence the use of closures. Our results suggest that customary management institutions are not resilient to factors such as population growth and economic modernization. If customary management is to be used as a basis for modern conservation initiatives, cross-scale institutional arrangements such as networks and bridging organizations may be required to help filter the impacts of socioeconomic transformations.  相似文献   
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Abstract:  Maintaining connectivity in fragmented landscapes is a key principle of biological conservation. Although corridors are a widely accepted approach to connecting populations, their merits are still debated, and they may be impractical in many situations. A focus on management of the vegetation matrix between populations has been advocated as an alternative way to deal with habitat fragmentation and has theoretical support. We combined microsatellite DNA and demographic data to provide an empirical account of how two forms of agricultural land use affect the connectivity of insular populations of an endangered skink in southern New Zealand. The grand skink ( Oligosoma grande ) lives in small populations (approximately 20 individuals) on rock outcrops separated from one another by 50–150 m of inhospitable matrix vegetation (either native tussock grassland or exotic pasture). Skinks typically dispersed short distances, and the nature of the matrix both quantitatively and qualitatively affected dispersal dynamics. Skink populations in pasture were significantly more genetically structured and had less genetic variation than similar populations in tussock, implying less dispersal between populations in pasture than tussock. Furthermore, although female-biased dispersal was a feature of populations in tussock, no sex bias was evident in pasture. In addition, Bayesian individual-based genetic assignment tests that incorporated prior mark-recapture information revealed that some populations produced many emigrants but received few immigrants, whereas other populations were relatively insular. Patterns of dispersal and response to matrix vegetation were complex, and the causes of these patterns deserve attention in future studies of habitat fragmentation. Managing the vegetation matrix may be a practical way to connect animal populations in some situations.  相似文献   
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Abstract:  As part of the Missouri Ozark Forest Ecosystem Project (MOFEP), we experimentally evaluated the impacts of forest management on the relative abundance of amphibians and reptiles in Missouri's Ozark forests (U.S.A.). Using large study sites (average size of 400 ha) as the experimental unit, we tested the effects of uneven-aged and even-aged forest management treatments compared with no-harvest management (i.e., control) on the relative abundance of 13 focal amphibian and reptile species. Within even-aged management sites, we also focused on the local-scale effects of clearcutting on these species by comparing relative abundance among plots located within clearcut stands, 50 m away from clearcut stands, and 200 m away from clearcut stands. Pretreatment sampling of species abundance occurred from 1992 through 1995, and post-treatment sampling occurred from 1997 through 2000. At the landscape scale, treatment significantly affected the abundance of Bufo americanus . This species declined less on even-aged management sites than on control sites, but the general decline on all sites suggests that other factors may have contributed to this result. Within even-aged management sites, most amphibian species declined and some reptile species increased relative to pretreatment abundances within clearcut stands. We found significant effects of distance from clearcut for two amphibian species, Ambystoma maculatum and Rana clamitans, and two reptile species, Scincella lateralis and Sceloporus undulatus . In general, we conclude that clearcuts within even-aged management sites locally affected amphibian and reptile species but, at a larger spatial scale, we did not detect significant effects of even-aged and uneven-aged forest management. These findings represent relatively short-term data but suggest that forest management and maintenance of biodiversity may be compatible when relatively small amounts of the landscape are disturbed.  相似文献   
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