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941.
Eugenio Figueroa B. Enrique Calfucura T. 《Environment, Development and Sustainability》2010,12(5):647-667
Searching for practical means to assessing economic growth’s sustainability, we extend a standard theoretical model to calculate “true” income measures for Chile, during the 1985–2004 period, and use estimates of natural capital depreciation to obtain genuine national saving measures. We found that, for the period, Chile’s economic growth was sustainable, even when approximately 2.5% of the income recorded by national accounts corresponded to depreciation of natural resources plus costs of atmospheric pollution. This performance can be partially explained by policies implemented to force fiscal responsibility and to assure wise public investment and expending during a natural resource driven growth. This evidence reinforces recent findings contradicting the natural resource curse, and the indirect negative effect of resource abundance over growth that would operate through the quality of institutions. 相似文献
942.
This paper presents the present status of food security and ecological footprint, an indicator of environmental sustainability of the coastal zones of Bangladesh. To estimate the present status of the food security and ecological footprint of the coastal zone of Bangladesh, primary and secondary data were collected, and the present status of food security and environmental degradation (in terms of ecological footprint) were calculated. To estimate the household food security, primary data were also collected from all the households in a representative selected village. A quantitative method for computation of food security in grain equivalent based on economic returns (price) is developed, and a method of measuring sustainable development in terms of ecological footprint developed by Wackernagel is used to estimate the environmental sustainability (Wackernagel and Rees in Our ecological footprint: reducing human impact on the earth. New Society, Gabrioala, BC, 1996; Chambers et al. in Sharing nature’s interest-ecological footprint as an indicator of sustainability. Earthscan, London, 2000). Overall status of food security at upazila levels is good for all the upazilas except Shoronkhola, Shyamnager and Morrelgonj, and the best is the Kalapara upazila. But the status of food security at household levels is poor. Environmental status in the coastal zones is poor for all the upazilas except Kalapara and Galachipa. The worst is in the Mongla upazila. Environmental status has degraded mainly due to shrimp culture. This study suggests that control measures are needed for affected upazilas and any further expansion of the shrimp aquaculture to enhance the food security must take into account the environmental aspects of the locality under consideration. 相似文献
943.
Diana Sietz Sabino Edgar Mamani Choque Matthias K. B. Lüdeke 《Regional Environmental Change》2012,12(3):489-505
Smallholder livelihoods in the Peruvian Altiplano are frequently threatened by weather extremes, including droughts, frosts and heavy rainfall. Given the persistence of significant undernourishment despite regional development efforts, we propose a cluster approach to evaluate smallholders’ vulnerability to weather extremes with regard to food security. We applied this approach to 268 smallholder households using information from two existing regional assessments and from our own household survey. The cluster analysis revealed four vulnerability patterns that depict typical combinations of household attributes, including their harvest failure risk, agricultural resources, education level and non-agricultural income. We validated the identified vulnerability patterns by demonstrating the correlation between them and an independently reported damage: the purchase of food and fodder resulting from exposure to weather extremes. The vulnerability patterns were then ranked according to the different amounts of purchase. A second validation aspect accounted for independently reported mechanisms explaining smallholders’ sensitivity and adaptive capacity. Based on the similarities among the households, our study contributes to the understanding of vulnerability beyond individual cases. In particular, the validation strengthens the credibility and suitability of our findings for decision-making pertaining to the reduction of vulnerability. 相似文献
944.
G. N. Tikhonova I. A. Tikhonov E. V. Kotenkova A. I. Munteanu I. G. Uspenskaya Yu. N. Konovalov V. I. Burlaku V. F. Kiku S. D. Georgitsa N. K. Karaman V. B. Nistreanu A. N. Mal’tsev 《Russian Journal of Ecology》2012,43(3):236-242
Comparative analysis of the structure of small mammal communities has been performed in two European cities located in different biomes: Chisinau (2008?C2009) and Yaroslavl (1994?C2002). The parameters studied included abundance, species composition, similarity and difference of faunas, species diversity, and proportions of groups differing in predisposition to synanthropy. It has been found that the structure of small mammal communities in these cities depends on specific physiographic conditions of the surrounding areas and on the distinctive features of the cities themselves (their structure, age, etc.). The similarity between the faunas is accounted for by the common ecological patterns of fauna formation in the biota of urban cenoses. 相似文献
945.
Human impacts on fire occurrence: a case study of hundred years of forest fires in a dry alpine valley in Switzerland 总被引:1,自引:1,他引:1
Thomas Zumbrunnen Patricia Menéndez Harald Bugmann Marco Conedera Urs Gimmi Matthias Bürgi 《Regional Environmental Change》2012,12(4):935-949
Forest fire regimes are sensitive to alterations of climate, fuel load, and ignition sources. We investigated the impact of human activities and climate on fire occurrence in a dry continental valley of the Swiss Alps (Valais) by relating fire occurrence to population and road density, biomass removal by livestock grazing and wood harvest, temperature and precipitation in two distinct periods (1904–1955 and 1956–2006) using generalized additive modeling. This study provides evidence for the role played by humans and temperature in shaping fire occurrence. The existence of ignition sources promotes fire occurrence to a certain extent only; for example, high road density tends to be related to fewer fires. Changes in forest uses within the study region seem to be particularly important. Fire occurrence appears to have been negatively associated with livestock pasturing in the forest and wood harvesting, in particular during the period 1904–1955. This study illustrates consistently how fire occurrence has been influenced by land use and socioeconomic conditions. It also suggests that there is no straightforward linear relationship between human factors and fire occurrence. 相似文献
946.
Research into landscape history makes it possible to follow landscape changes in the past and support landscape management, conservation and restoration programs. Floodplain habitats are lost, isolated and fragmented on account of land use. Nowadays, these habitats are threatened by modifications in the natural water regime, as well as agricultural and forestry practices. Floodplains have great importance because they provide a transition between aquatic habitats and terrestrial biotopes. Our analysis of aerial photographs and topographical maps revealed that the major predicted changes in the study area are related to agricultural abandonment and afforestation. The comparison of land cover maps from 1784 to 2005 showed intensification of agriculture with land cover conversions from arable land and orchards to grasslands, marshes and woodlands. The land use types that are mostly responsible for the fragmentation of the landscape are arable land, economic plantations and orchards. We found that fragmentation was greater after 1956. This was caused by socioeconomic changes and showed that the habitats of floodplains have changed intensively during the last 200 years. Knowledge of this last 200 years of history contributes to a more careful and wiser management of the region through biodiversity protection and environmental development. 相似文献
947.
Community participation and community based management are topical themes in current policy and discussion revolving around decision-making processes especially those dealing with natural resources management.This review shows that while governments have accepted the need to either cede or devolve control and management of natural resources to the local communities,the communities are not part and parcel of the planning and budgeting which are crucial in decisionmaking.Communities were seen to be more involved in the implementation of natural resource management programs but lacked ownership of the projects.This causes lack of commitment to the programs and at times hostile reaction from the communities.The communities are always at the receiving end when it pertains to losses in the exchange.Community participation was shown to be effective when the local population is involved not as co-operating users but as natural resource managers or owner managers. 相似文献
948.
Species composition of fishes was studied in rivers (capture sites) inhabited by the riffle minnow. In some localities, this species proved to occupy a leading position in the ichthyofauna, being obviously dominant. In small rivers, 16 species were caught together with it, including seven species regularly occurring in catches. The relative abundance of riffle minnow showed a moderate positive correlation with that of the gudgeon (0.568) and a nonsignificant negative correlation (?0.399) with that of the bleak. It is probable that the population dynamics of riffle minnow are determined mainly by natural intraspecific mechanisms rather than by water quality, which has changed only slightly in the rivers studied. 相似文献
949.
The impact of emissions from the Siberian Chemical Plant (Tomsk oblast) on reproduction and embryonic development of the fieldfare was studied. Bird abundance, clutch size, and egg volume in the impact and background (control) zones were similar, but partial brood mortality in the impact zone proved to be significantly higher, and the frequency of embryonic pathologies (including developmental abnormalities) was also several times higher than in the control. 相似文献
950.
J. R. Park M. J. Stabler P. J. Jones S. R. Mortimer J. R. Tiffin R. B. Tranter 《Environment, Development and Sustainability》2009,11(4):735-750
The issue of the sustainable development of rural economies in England has recently received considerable attention. This
is because many of the poorest areas in the country are rural, often of high environmental quality, but suffering from high
unemployment and a lack of services and facilities. The rapid decline in agricultural incomes and in-migration of affluent
urban workers since 1990 has exacerbated economic inequality in such areas. A number of factors have the potential to drive
rural development and this paper applies, and considers, the feasibility of a method from the USA for combining economic and
environmental variables in a regional growth model to examine the hypothesis that environmental quality is an important determinant
of sustainable rural development in England. The model output suggests that, although environmental quality does play a role
in sustainable rural development in England there are other, more important, factors driving development. These include business
and communications infra-structure, the degree and opportunities for commuting and underlying employment prospects. The robustness
and limitations of the method for combining economic and environmental variables is discussed in relation to the spatial interrelatedness
of Local Authority Districts in England, and conclusions are drawn about areas for refinement and improvement of the method.
相似文献
J. R. ParkEmail: |