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991.
The Okavango Delta in Botswana hosts abundant wildlife and a human population with diverse livelihoods. Representing a heterogeneous landscape nuanced by spatial and temporal variability, the region has recently seen an expansion of floodwaters with social impacts ranging from livelihood disruption to human displacement. This article reports on in-depth interviews conducted in 2012 regarding these transitions in Mababe, a community in the eastern Okavango Delta, to evaluate how dynamic environmental processes alter perceptions and livelihood responses. We focus on community members’ variable interactions with wildlife in spaces of human–wildlife overlap also experiencing change. While human–wildlife interactions can have negative effects, we find that perpetuating the common narrative of human–wildlife conflict overlooks how disruptions can usher in new relationships between people and animals. In order to move beyond the conflict narrative, we conclude that spatial and temporal context is essential to evaluate effects of dynamic, uneven, and sometimes unpredictable human–wildlife encounters. 相似文献
992.
Emily Benton Hite David Barton Bray Elvira Duran Armando Rincón-Gutiérrez 《社会与自然资源》2017,30(5):613-626
Studies of coffee agroecosystems have focused on their role in providing habitat for biodiversity across a range of management intensities. These studies have not taken into account the temporal and spatial transformations in coffee landscapes and their impacts on structural heterogeneity and biodiversity, nor systematically linked these transformations to farmer management responses to price and policy shocks. We utilize a coupled natural–human system framework to examine the historical transformations of the coffee landscape in a matrix of community-protected forests in a coffee-growing community in Oaxaca, Mexico, and study how those transformations impact tree biodiversity across a range of management options, including formerly certified organic and conventional coffee, abandonment, and conversion. The coffee landscape has historically transitioned from forests and fields (1950s–1960s) to one dominated by coffee (1970s–1980s) to a richly mosaic and biodiverse landscape (1990–2010) resulting from 43% recent abandonment and conversion of coffee back to forest and fields. 相似文献
993.
Merrill Baker-Médard 《社会与自然资源》2017,30(6):723-737
Drawing on ethnographic case studies from Madagascar, this research shows that multiple marine conservation projects have institutionalized inequitable access to marine recourses along gendered lines. Despite discursive and institutional shifts toward more “collaborative” and “community-based” conservation programing, there is a deficiency of women’s nominal as well as effective participation in community management organizations. This research shows that conservation organizations’ focus on proximate drivers of marine resource use, or a politics of picking the “low-hanging fruit,” over ultimate drivers such as global commodity chains, places disproportionate emphasis on marine spatial enclosures and restricting specific, and gendered, harvest methods. To address gender bias concerning access to and control over natural resources, we must go beyond the rhetoric of “community involvement” to address gendered inequalities in conservation decision making, and whose interests are served by conservation projects. 相似文献
994.
A revised typology of Australian tropical rivers was applied to the complete channel network (named and major rivers) shown on 1:250 000 topographic maps for three large drainage basins in northern Australia (Daly River, NT; Fitzroy River, WA; Flinders River, Qld). Reach mapping and classification were conducted using the revised typology. The 12 major river types proposed were: (1) bedrock rivers; (2) bedrock‐confined and ‐constrained rivers; (3) low sinuosity (straight) rivers; (4) meandering rivers; (5) wandering rivers; (6) anabranching rivers; (7) chains of ponds; (8) gullies; (9) floodouts; (10) lakes, swamps, billabongs and wetlands; (11) non‐channelized valley floors; and (12) estuarine rivers. The 12 major river types were developed based on river reach mapping for more than 264 000 km2 of tropical Australian catchments. At scales larger than 1:250 000, subdivision of each major river type is recommended. In the Daly and Fitzroy catchments, confined and constrained rivers dominate, whereas in the Flinders and Fitzroy catchments, anabranching rivers dominate. The dominant river types need benchmarking with adequate numbers of control reaches so that channel changes induced by human and natural impacts can be measured by reference to the stability of these controls. Wandering rivers, floodouts and non‐channelized valley floors were rare for the 1:250 000 channel network in northern Australia but need inclusion in national parks. 相似文献
995.
鉴于中国对生态保护的投入与奖惩皆以县域为基本单元,需要开展县域尺度生态保护效果的监测评估,以期为县域生态环境质量考核提供科学依据。本文定量分析了近15年县域尺度优良生态系统面积及植被覆盖度变化,及其与生态保护项目数量的关系,进而评估生态保护措施在县域生态变化中的效果,并评价工程措施的地域适宜性。结果表明:① 中国东北地区、南方亚热带区、青藏高原东南部的县域优良生态系统面积占比多高于50%,西北地区、西南喀斯特区、华北平原等县域优良生态系统占比多低于20%。② 近几十年,生态保护重点是生态脆弱区,青海三江源、藏东南、川西、祁连山、新疆南部等西部地区的县域生态保护项目数量多大于5个,东部沿海地区则少于或等于1个。③ 2000-2015年,中国53%县域的优良生态系统面积占比提高,黄土高原、黄淮海平原、京津冀、川黔渝、两广等地区的县域植被覆盖度明显上升,而新疆北部、西藏中部、内蒙古中东部等干旱半干旱区、长三角等区域植被覆盖度下降。④ 生态保护项目数量与优良生态系统、植被覆盖度变化等反映生态状况改善的指标并未呈现正相关关系,生态保护应遵循优良生态系统分布格局,气候变化背景下造林等工程措施应遵循自然规律与地带性差异。 相似文献
996.
997.
Due to well-documented declines in many shark populations there is increasing pressure to implement new management and rebuilding strategies at the national and international scale. Since 2009, fifteen coastal countries in the Atlantic, Indian and Pacific Oceans have opted to ban commercial shark fishing altogether, and have laws that prohibit the possession, trade or sale of sharks and shark products. These ‘shark sanctuaries’ collectively cover >3% of the world’s oceans, a similar coverage as all currently established marine protected areas combined. Despite their prominence, and an intense scientific debate about their usefulness, the condition of shark sanctuaries has not yet been empirically evaluated. Here, we report results from a global diver survey used to set baselines of shark populations, human use patterns, public awareness and threats in all 15 shark sanctuaries, and contrasted with observations from 23 non-sanctuary countries. Specific results varied by country, but there were some general trends: i) shark sanctuaries showed less pronounced shark population declines, fewer observations of sharks being sold on markets, and lower overall fishing threats compared to non-shark sanctuaries, ii) bycatch, ghost gear, marine debris and habitat destruction are significant threats that are often not addressed by sanctuary regulations and need to be resolved in other ways, and iii) participants in sanctuaries were more optimistic about the survival of shark populations in local waters, but also highlighted the need for further conservation efforts. These results suggest that shark sanctuaries, as seen through the lens of local experts, may be a helpful conservation tool but likely not sufficient in isolation. There is an urgent need for higher-resolution data on shark abundance, incidental catch, and markets to direct priority conservation needs and optimize the conservation benefits of existing and future shark sanctuaries. 相似文献
998.
《自然地理学》2013,34(4):351-373
Stone retaining walls in urban Hong Kong provided vertical habitats for spontaneous colonization by a diversified humid-tropical flora with large trees. A citywide survey assessed wall and tree characteristics to understand wall-tree relationships and identify conservation candidates. Nonparametric correlations were computed between 28 wall attributes versus tree count, tree biomass, and species-vegetation factors. Most of the 245 walls, with 1275 trees, were in residential areas. Moraceae dominated the 30 tree species, predominantly genus Ficus, and especially F. microcarpa. Natives formed the overwhelming majority, largely with pioneer and ruderal traits. The positive effect of adjacent built-up land use and negative effect of wall exposure indicated sheltering from wind could facilitate tree growth. Wall height was a key determinant as taller walls furnished more surfaces free from human disturbance and conducive to seed deposition by frugivorous birds and bats. Stone width offered more horizontal microsites for seeds to lodge. Stone roughness operated at the microscale to encourage nonarboreal vegetation. Joint attributes exerted strong influence on tree growth and less so on nontree affiliates. The walls-cum-vegetation, many older than 100 years, presented a precious natural-cum-cultural heritage, deserving protection as an urban ecological asset. 相似文献
999.
Simon Bolwig Derek Pomeroy Herbert Tushabe David Mushabe 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):115-130
Geografisk Tidsskrift, Danish Journal of Geography 106(2): 115–130, 2006 This paper examines the relationship between the intensity of agricultural land use and the abundance and richness of trees and birds in a humid tropical developing region where natural vegetation is being rapidly converted into farmland under market and population pressures. We analysed survey data on land use, birds and woody plants collected in 14 study sites situated within smallholder cropland and commercial plantations in southern Uganda. Commercial plantations had very few trees and only 10% of the original bird species. Land use intensification in smallholder systems also showed losses in bird abundance and species richness, but not nearly as much as in plantations. In both systems the impact of intensification was much bigger on the specialised and threatened birds compared to the less specialised species. This argues strongly for ‘species-sensitive’ conservation policies combining protected areas with land use regulation in areas undergoing intensification. We also found a much higher loss in bird biodiversity during the first phases of land use intensification (when larger tracts of forest are cleared) than in later phases characterised by clearing of smaller patches of vegetation and improved management of farm trees. This suggests high pay-offs to geographical targeting of conservation efforts in farmed landscapes. 相似文献
1000.
J. Christopher Brown 《The Professional geographer》2013,65(1):106-118
Productive conservation, a sustainable development concept for the Amazon, ideally leads to economic development in rural areas with conservation of rain forest ecosystems. This study evaluates the human and environmental dynamics of productive conservation in Rondonia, Brazil, using as a case study beekeeping, which has been promoted by the World Bank-funded Rondonia Natural Resources Development Project. Promoters of beekeeping have given little attention to basic ecological or political economic issues that determine whether the practice contributes to ideals of productive conservation. While beekeeping can generate significant increases in household income, beekeeping cooperatives may become overdependent on donor funds. Once the flow of productive conservation donor funds stops, organizations may fail, making it too difficult for beekeepers to maintain their operations. Beekeeping does not lead directly toward rain forest conservation. Moreover, beekeeping almost exclusively employs introduced Africanized “killer” bees, commercially exploitable in the Amazon only because deforestation has temporarily created suitable habitats for them. Given the human and environmental configuration of beekeeping in Rondonia, the paper suggests ways to direct beekeeping toward accomplishing the goals of productive conservation. 相似文献