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71.
Hyperarid, arid, and semi-arid lands represent over a third of the Earth’s land surface, and are home to over 38 % of the increasing world population. Freshwater is a limiting resource on these lands, and withdrawal of groundwater substantially exceeds recharge. Withdrawals of groundwater for expanding agricultural and domestic use severely limit water availability for groundwater dependent ecosystems. We examine here, with emphasis on quantitative data, case histories of groundwater withdrawals at widely differing scales, on three continents, that range from the impact of a few wells, to the outcomes of total appropriation of flow in a major river system. The case histories provide a glimpse of the immense challenge of replacing groundwater resources once they are severely depleted, and put into sharp focus the question whether the magnitude of the current and future human, economic, and environmental consequences and costs of present practices of groundwater exploitation are adequately recognized. 相似文献
72.
Per Angelstam Kjell Andersson Maths Isacson Dmitri V. Gavrilov Robert Axelsson Mattias Bäckström Erik Degerman Marine Elbakidze Elena Yu. Kazakova-Apkarimova Lotta Sartz Stefan Sädbom Johan Törnblom 《Ambio》2013,42(2):146-159
Barriers and bridges to implement policies about sustainable development and sustainability commonly depend on the past development of social–ecological systems. Production of metals required integration of use of ore, streams for energy, and wood for bioenergy and construction, as well as of multiple societal actors. Focusing on the Swedish Bergslagen region as a case study we (1) describe the phases of natural resource use triggered by metallurgy, (2) the location and spatial extent of 22 definitions of Bergslagen divided into four zones as a proxy of cumulative pressure on landscapes, and (3) analyze the consequences for natural capital and society. We found clear gradients in industrial activity, stream alteration, and amount of natural forest from the core to the periphery of Bergslagen. Additionally, the legacy of top-down governance is linked to today’s poorly diversified business sector and thus municipal vulnerability. Comparing the Bergslagen case study with other similar regions in Russia and Germany, we discuss the usefulness of multiple case studies. 相似文献
73.
Managing the Three-Rivers Headwater Region, China: From Ecological Engineering to Social Engineering 总被引:1,自引:0,他引:1
Yiping Fang 《Ambio》2013,42(5):566-576
The three-rivers headwater region (THRHR) of Qinghai province, China plays a key role as source of fresh water and ecosystem services for central and eastern China. Global warming and human activities in the THRHR have threatened the ecosystem since the 1980s. Therefore, the Chinese government has included managing of the THRHR in the national strategy since 2003. The State Integrated Test and Demonstration Region of the THRHR highlights the connection with social engineering (focus on improving people’s livelihood and well-being) in managing nature reserves. Based on this program, this perspective attempts a holistic analysis of the strategic role of the THRHR, requirements for change, indices of change, and approaches to change. Long-term success of managing nature reserves requires effective combination of ecological conservation, economic development, and social progress. Thus, the philosophy of social engineering should be employed as a strategy to manage the THRHR. 相似文献
74.
Baseline assessment for environmental services payments from satellite imagery: a case study from Costa Rica and Mexico 总被引:1,自引:0,他引:1
Kalacska M Sanchez-Azofeifa GA Rivard B Calvo-Alvarado JC Quesada M 《Journal of environmental management》2008,88(2):348-359
In this study we evaluate the accuracy of four global and regional forest cover assessments (MODIS, IGBP, GLC2000, PROARCA) as tools for baseline estimation. We conduct this research at the national scale for Costa Rica and for two tropical dry forest study sites in Costa Rica (Santa Rosa) and Mexico (Chamela-Cuixmala). We found that at the national level, the total forest cover accuracy of the four land cover maps was inflated due to an overestimation of forest in areas with an evergreen canopy. However, the four maps greatly underestimated the extent of the deciduous forest (dry forest); an ecosystem that faces high deforestation pressure and poses complications to the mapping of its extent from remotely sensed data. For the tropical dry forest sites, all maps have low forest cover accuracies (mean for Santa Rosa: 27%; mean for Chamela-Cuixmala: 56%). This has implications for policy implementation. 相似文献
75.
Robins L 《Environmental management》2008,42(5):833-846
This paper aims to give practical meaning to ‘capacity building’ through (a) identifying a suite of practical measures, such
as mentoring or best practice guidelines, that have been shown to or are considered to build human, social, institutional,
and economic capital; (b) placing these measures within a broader systems framework; and (c) exploring stakeholder feedback
on specific measures to inform framework implementation. The 29 measures described provide actors, whether government or nongovernment,
with a suite of practical investment choices for building capacity. These measures are then clustered into eight groups according
to their primary purpose and placed within a systems framework. The framework provides a tool for actors with responsibilities
for or an interest in capacity building to inform more holistic and strategic targeting of effort and investment. Stakeholder
feedback gathered through surveys and workshops is subsequently reported to further inform implementation of specific measures
within the framework’s eight groupings. The framework presented may be built upon through the identification and inclusion
of further capacity building measures. The research is conducted within the context of decentralized governance arrangements
for natural resource management (NRM), with specific focus on Australia’s recently formalized 56 NRM regions and their community-based
governing boards as an informative arena of learning. Application of the framework is explored in the Australian setting through
the identification and comparison of measures supported and most preferred by four major stakeholder groups, namely board
members, regional NRM organization staff, policy/research interests, and Indigenous interests. The research also examines
stakeholder perceptions of capacity issues, and whether these issues are likely to be addressed through implementing their
preferred measures.
相似文献
Lisa RobinsEmail: |
76.
We documented valley and channel characteristics and wood loads in 19 reaches of forested headwater mountain streams in the
Bighorn National Forest of northern Wyoming. Ten of these reaches were in the Upper Tongue River watershed, which has a history
of management including timber harvest, tie floating, and road construction. Nine reaches were in the North Rock Creek watershed,
which has little history of management activities. We used these data to test hypotheses that (i) valley geometry correlates
with wood load, (ii) stream gradient correlates with wood load, and (iii) wood loads are significantly lower in managed watersheds
than in otherwise similar unmanaged watersheds. Statistical analyses of the data support the first and third hypotheses. Stream
reaches with steeper valley side slopes tend to have higher wood loads, and reaches in managed watersheds tend to have lower
wood loads than reaches in unmanaged watersheds. Results do not support the second hypothesis. Shear stress correlated more
strongly with wood load than did stream gradient, but statistical models with valley-scale variables had greater explanatory
power than statistical models with channel-scale variables. Wood loads in stream reaches within managed watersheds in the
Bighorn National Forest tend to be two to three times lower than wood loads in unmanaged watersheds. 相似文献
77.
成都市活水公园人工湿地系统10年运行回顾 总被引:8,自引:1,他引:7
成都市活水公园是1997年建成的世界上首座以展示"人工湿地水处理系统"和"仿峨眉山亚热带自然植被"为主要内容的、以水保护为主题的生态公园。它所展示的人工湿地处理系统工程,现己正常运行了10年。本文通过回顾10年来活水公园人工湿地工程设计、建设与运行的经验,结合当前己建和在建的人工湿地工程中所存在的一些问题,提出一些看法与建议。供从事人工湿地工程设计、施工及管理人员参考。 相似文献
78.
We compared measures of ecosystem state across six adjacent land-tenure groups in the intact tropical savanna landscapes of
northern Australia. Tenure groups include two managed by Aboriginal owners, two national parks, a cluster of pastoral leases,
and a military training area. This information is of relevance to the debate about the role of indigenous lands in the Australian
conservation estate. The timing and frequency of fire was determined by satellite imagery; the biomass and composition of
the herb-layer and the abundance of large feral herbivores by field surveys; and weediness by analysis of a Herbarium database.
European tenures varied greatly in fire frequencies but were consistently burnt earlier in the dry season than the two Aboriginal
tenures, the latter having intermediate fire frequencies. Weeds were more frequent in the European tenures, whilst feral animals
were most abundant in the Aboriginal tenures. This variation strongly implies a signature of current management and/or recent
environmental history. We identify indices suitable for monitoring of management outcomes in an extensive and sparsely populated
landscape. Aboriginal land offers a unique opportunity for the conservation of biodiversity through the maintenance of traditional
fire regimes. However, without financial support, traditional practices may prove unsustainable both economically and because
exotic weeds and feral animals will alter fire regimes. An additional return on investment in Aboriginal land management is
likely to be improved livelihoods and health outcomes for these disadvantaged communities. 相似文献
79.
Mortimer MJ 《Environmental management》2008,41(5):640-653
Political and legal conflicts between the need for targeted private forest conservation and the continued assurance of private
property rights in the U.S. presents a seemingly intractable resource management problem. Scandinavian use of habitat protection
areas on private forests offers an additional tool that may be suitable for solving the historical and on-going tension found
within U.S. efforts to reconcile desires to maintain lands in a forested condition while also respecting private property
rights. This article presents a comparative cross-sectional policy analysis of Sweden, Finland, and the U.S., supported with
a supplemental case example from the Commonwealth of Virginia. Similarities in all three countries among forest ownership
patterns, use of public subsidies, and changing attitudes towards conservation are generally encouraging. Additionally, Virginia’s
current consideration and development of state-wide forest policies focused on forestland and open space conservation suggests
both a need and an opportunity to systematically assess the applicability of the Nordic forest reserve approach to local private
forest conservation. Future research at a high-resolution, and specifically at the state level, should focus on the social
and political factors that would ultimately determine the viability of a forest reserve program. 相似文献
80.
Snowmobile use in Yellowstone National Park has been shown to impact air quality, with implications for the safety and welfare
of Park staff and other Park resource values. Localized impacts have been documented at several high-use sites in the Park,
but the broader spatial variability of snowmobile emissions and air quality was not understood. Measurements of 87 volatile
organic compounds (VOCs) were made for ambient air sampled across the Park and West Yellowstone, Montana, during 2 days of
the 2002–2003 winter use season, 1 year before the implementation of a new snowmobile policy. The data were compared with
similar data from pristine West Coast sites at similar latitudes. Backward trajectories of local air masses, alkyl nitrate-parent
alkane ratios, and atmospheric soundings were used to identify the VOC sources and assess their impact. Different oversnow
vehicle types used in the Park were sampled to determine their relative influence on air mass pollutant composition. VOCs
were of local origin and demonstrated strong spatiotemporal variability that is primarily influenced by levels of snowmobile
traffic on given road segments at different times of day. High levels of snowmobile traffic in and around West Yellowstone
produced consistently high levels of benzene, toluene, and carbon monoxide. 相似文献