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821.
Colin Thor West 《Environment, Development and Sustainability》2011,13(1):217-235
The Arctic is a region of the world experiencing extremely rapid climatic and social change. Indigenous communities have faced
similar challenges for millennia and have historically demonstrated remarkable resilience to socioecological perturbations.
In contemporary contexts, however, it appears that the pace and extent of change is overwhelming the adaptive capacities of
many indigenous communities. Scholars recently completed a survey of living conditions spanning the circumpolar Arctic to
quantitatively document the impacts of social and ecological stress across regions. The database they created is called the
Survey of Living Conditions in the Arctic or SLiCA. This article explores the utility of using this dataset to compare livelihood
systems across three sub-regions of Alaska and four sub-regions within the Chukotka Autonomous Okrug of the Russian Federation.
The results point out that livelihood systems in Chukotka have a substantially lower level of sustainability than in Northwest
Alaska due to the high prevalence of vulnerable households. 相似文献
822.
Luca Salvati Alberto Mancini Sofia Bajocco Roberta Gemmiti Margherita Carlucci 《Regional Environmental Change》2011,11(4):767-777
In recent years, the surface area affected by land degradation (LD) has significantly increased in southern European regions
where the socioeconomic development has been proposed as a basic factor underlying the degree of vulnerability to LD. This
paper investigates the correlation between several socioeconomic indicators and the level of vulnerability to LD in Italy,
expressed as changes (1990–2000) in a composite index of land vulnerability (ΔLVI). The analysis was carried out over 784
local districts. The impact of per capita value added, agricultural intensity, industrial and tourism concentration, and urban
growth was separately tested on ΔLVI. Results indicate that a lower district value added, crop intensification, irrigation,
and the level of land vulnerability to degradation are strongly associated with the increasing level of land vulnerability
over time, highlighting the role of the socioeconomic development as a main process underlying LD. In this framework, spatially
equitable sustainable development may represent the effective strategy to mitigate the detrimental effects of economic growth
and regional disparities on Mediterranean LD. 相似文献
823.
The Andaman Islands characterize one of the relatively unexplored coral reef zones of the Indian subcontinent. A few benthic biodiversity studies have been carried out to date, but several coral and algal species still remain to be evaluated in terms of their abundance, vigour and conservation priority. In absence of a comprehensive, reliable dataset, inter-relationships between anthropogenic impacts and climate alterations with the coral reefs cannot be assessed authentically. This paper addresses the coupled themes of biodiversity and reef management in the Andaman Islands by examining the percentage cover of corals and benthic algae from shallow-water ecosystems across the coasts of Havelock, Neil, Ross, Jolly Buoy Islands and Chidiyatapu beach proximal to Port Blair. Four major reef types were observed: coral-dominated, algae-dominated, neutral setting and algae overgrowing dead reefs. Jolly Buoy Island had the highest percentage cover of scleractinian corals and crustose coralline algae. Turf algae were most abundant at the Ross Island, while other macroalgae showed highest abundance at Chidiyatapu. Overall species diversity values for corals and algae were highest at the Jolly Buoy and Chidiyatapu, respectively. Given that corals and algae are critical reef components, management paradigms must consider the abundance and frequency of both these biogenic entities in the seascape. The needs, expectations and objectives of the people dependent on coral reef ecosystems also need to be considered. Long-term monitoring is imperative in understanding the natural typology of reefs and managing the possible algal encroachments. Refined management efforts that include greater thrust on development of marine protected areas and reserves; establishment of connectivity between various coral ecosystems of the region; control of invasive algae; and increasing awareness among the local people as well as tourists will ensure continued support of ecosystem to maintain healthy reefs. Collectively, the results are used to promote some strategies to conserve the Andaman coral reefs and cope with the detrimental anthropogenic and climate changes in these coastal habitats. 相似文献
824.
John Seidensticker 《Regional Environmental Change》2016,16(1):167-179
Corridors (variably called landscape linkages, connectors, and gateways) are expanses of a landscape that facilitate the flow or movement of individuals, genes, and ecological processes. Protected areas with their buffer zones and the corridors that connect them are cornerstones of modern conservation actions to maintain the biodiversity we have and restore what we have lost. Policy and governance to guide the establishment and management of protected areas and supporting buffer zones is well established in the Central Indian Highlands. A policy and governance structure to create the context and enabling conditions for corridor maintenance, creation, and recovery is emerging but is constrained by the reigning land-management paradigm that separates conservation from development rather than mainstreaming species and habitat conservation into the rural development agenda. Well-nourished, healthy human populations and healthy ecosystems are inextricably linked. The worsening ecological conditions in the Central Indian Highlands can trigger the emergence of a common agenda for an inclusive, caring, and environment-friendly mode of development. The alternative is the business-as-usual scenario: a continuation of worsening ecological conditions. Entry points through the biodiversity, agriculture production, resource extraction, and economic/social sectors to enable integrated sustainable landscape management are identified. These include deepening what it means to successfully conserve a species combined with explicit threat analysis for at-risk tigers and the landscapes that supports them; landscape scenario modeling to advance communication by synthesizing diverse forms of research and articulating and evaluating alternative socio-economic futures; and the use of the smart green infrastructure process as an approach to development rather than only as a way to mitigate environmental damage. Models are presented to scale up from isolated conservation interventions to collective impact that unites supportive government partners with individuals, NGOs, and economic interests to achieve viable long-term relationships in human and natural systems to value, maintain, and recover landscape connectivity. 相似文献
825.
Dynamic responses of photosystem II in the Namib Desert shrub, Zygophyllum prismatocarpum, during and after foliar deposition of limestone dust 总被引:1,自引:0,他引:1
van Heerden PD Krüger GH Kilbourn Louw M 《Environmental pollution (Barking, Essex : 1987)》2007,146(1):34-45
The effects of limestone dust deposition on vegetation in desert ecosystems have not yet been reported. We investigated these effects in a succulent shrub from the Namib Desert at a limestone quarry near Skorpion Zinc mine (Namibia). Effects of limestone dust were determined in Zygophyllum prismatocarpum (dollar bush) plants with heavy, moderate and no visible foliar dust cover by means of chlorophyll a fluorescence measurements. Limestone dust deposition decreased overall plant performance through loss of chlorophyll content, inhibition of CO(2) assimilation, uncoupling of the oxygen-evolving complex and decreased electron transport. Importantly, dynamic recovery occurred after termination of limestone extraction at the quarry. Recovery was accelerated by rainfall, mainly because of dust removal from leaves and stimulation of new growth. These results indicate that limestone dust has severe effects on photosynthesis in desert shrubs, but that recovery is possible and that, in arid environments, this process is modulated by rainfall. 相似文献
826.
Andreas Züttel 《Mitigation and Adaptation Strategies for Global Change》2007,12(3):343-365
Hydrogen storage and transportation or distribution is closely linked together. Hydrogen can be distributed continuously in
pipelines or batch wise by ships, trucks, railway or airplanes. All batch transportation requires a storage system but also
pipelines can be used as pressure storage system. Hydrogen exhibits the highest heating value per weight of all chemical fuels.
Furthermore, hydrogen is regenerative and environment friendly. There are two reasons why hydrogen is not the major fuel of
toady’s energy consumption: First of all, hydrogen is just an energy carrier. And, although it is the most abundant element
in the universe, it has to be produced, since on earth it only occurs in the form of water. This implies that we have to pay
for this energy, which results in a difficult economic task, because since the industrialization we are used to consuming
energy for free. The second difficulty with hydrogen as an energy carrier is the low critical temperature of 33 K, i.e. hydrogen
is a gas at room temperature. For mobile and in many cases also for stationary applications the volumetric and gravimetric
density of hydrogen in a storage system is crucial. Hydrogen can be stored by six different methods and phenomena: high pressure
gas cylinders (up to 800 bar), liquid hydrogen in cryogenic tanks (at 21 K), adsorbed hydrogen on materials with a large specific
surface area (at T < 100 K), absorbed on interstitial sites in a host metal (at ambient pressure and temperature), chemically bond in covalent
and ionic compounds (at ambient pressure), oxidation of reactive metals e.g. Li, Na, Mg, Al, Zn with water. These metals easily
react with water to the corresponding hydroxide and liberate the hydrogen from the water. Finally, the metal hydroxides can
be thermally reduced to the metals in a solar furnace. 相似文献
827.
A Simulation of Temporal and Spatial Variations in Carbon at Landscape Level: A Case Study for Lake Abitibi Model Forest in Ontario,Canada 总被引:2,自引:0,他引:2
Xiaolu Zhou Changhui Peng Qing-Lai Dang Jiaxin Chen Sue Parton 《Mitigation and Adaptation Strategies for Global Change》2007,12(4):525-543
Using a case study of the Lake Abitibi Model Forest (LAMF), this study aims to assess the temporal and spatial variability
in carbon storage during 1990–2000, and to present a comprehensive estimation of the carbon budget for LAMF's ecosystems.
As well, it provided the information needed by local forest managers to develop ecological and carbon-based indicators and
monitor the sustainability of forest ecosystems. Temporal and spatial carbon dynamics were simulated at the landscape level
using ecosystem model TRIPLEX1.0 and Geographical Information System (GIS). The simulated net primary productivity (NPP) and
carbon storage in forest biomass and soil were compared with field data and results from other studies for Canada's boreal
forests. The results show that simulated NPP ranged from 3.26 to 3.34 tC ha−1 yr−1 in the 1990s and was consistent with the range measured during the Boreal Ecosystem-Atmosphere Studies (BOREAS) in central
Canada. Modeled NPP was also compared with the estimation from remote sensing data. The density of total above-and belowground
biomass was 125.3, 111.8, and 106.5 tC ha−1 for black spruce, trembling aspen, and jack pine in the LAMF ecosystem, respectively. The total carbon density of forested
land was estimated at 154.4 tC ha−1 with the proportion of 4:6 for total biomass and soil. The analysis of net carbon balance of ecosystem suggested that the
LAMF forest ecosystem was acting as a carbon sink with an allowable harvest in the 1990s. 相似文献
828.
(E)-6,10-dimethyl-5,9-undecadien-2-ol (geranyl acetol), termed here fuscol, was identified as a male-produced pheromone emitted
by Tetropium fuscum (F.) and Tetropium cinnamopterum Kirby. In field experiments, traps baited with synthetic fuscol alone were not significantly attractive, but the combination
of fuscol plus host volatiles (a synthetic blend of monoterpenes plus ethanol) attracted significantly more male and female
T. fuscum and female T. cinnamopterum than did host volatiles alone. This is the first homoterpenoid alcohol to be described in the Cerambycidae, and the first
pheromone reported from the sub-family Spondylidinae. 相似文献
829.
Pursuing an integrated development and climate policy framework in Africa: options for mainstreaming
Climate change presents a major threat to the prospects for sustained economic development in Africa. In spite of this, climate change concerns do not feature prominently in the implementation of national and regional development programmes. The present paper identifies the likely trade-offs and synergies that may emerge from an integrated ‘development-climate’ approach to policy making. Also, the paper presents the case for the formulation and evaluation of an integrated policy approach based on four principle criteria, including; long-term environmental effectiveness, equity considerations, cost-effectiveness and the institutional compatibility of the policy combinations. What is more? The paper suggests specific options for mainstreaming climate change adaptation and mitigation in various sectoral development agenda such as; agricultural intensification, poverty eradication, rural development, urban renewal, energy security of supply and trade. Given the wide divergence of socio-economic systems and the peculiar challenges faced by individual countries in the continent, further research is required on robust country-specific strategies for pursuing an integrated development-climate policy framework. 相似文献
830.
Solar disinfection (SODIS) has been described as a cheap and effective method of treating contaminated water to inactivate
pathogenic microorganisms. In this study, SODIS was assessed for its efficacy in inactivating three enteric viruses (coxsackievirus
B3, coxsackievirus B5 and poliovirus), either on its own or in the presence of riboflavin as a disinfection enhancer. On its
own, SODIS produced a reduction of virus infectivity of 4–6 log10 in 6 h. In the presence of riboflavin, inactivation was more rapid in all viruses studied, and with coxsackievirus B5 and
poliovirus an extra 1–2 log10 increase in reduction of infectivity was observed after 6 h exposure. This study provides a practical example of low technology
methods which could be utilised to provide safe drinking water in various circumstances. 相似文献