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1.
This paper describes the informal groundwater market existing in the urban–peri-urban interface of Chennai. The private water
tanker suppliers and packaged water industries utilize the land and water resources of the peri-urban villages. Thus, the
groundwater sources in peri-urban areas play a significant role in meeting the growing urban demand. The villages that are
experiencing the groundwater market are highly influenced by the urbanization and its related activities, due to their proximity
to the city. The transfer of groundwater from the peri-urban villages not only deprives the peri-urban areas of their water
rights but also leads to environmental damage. Agriculture declined in the water marketed villages in the range of 20–95 per
cent during 1990–2007. The pre-monsoon and post-monsoon groundwater level fluctuation varied from 2–6 m to 0–5 m, respectively,
during 1971–2007. The declining trend of the groundwater table and agriculture is highly significant in the water marketing
villages. Moreover, the present groundwater quality is also in a susceptible state due to over extraction. Hence, strengthening
the legal and institutional framework to ensure an equitable access to water for both urban and peri-urban areas is urgently
required. This paper also describes the characteristics of the groundwater transfer, quantification of the marketed water,
the role of the existing regulatory framework, and the institutional mechanisms. Many stakeholder’s meeting and focus group
discussions have been conducted in the villages under study for understanding the socio-economic implications of the water
market. The study ultimately emphasized a sustainable groundwater extraction/market which will safeguard the interests of
the peri-urban and urban communities. 相似文献
2.
A quantitative study was conducted in 1998 to investigate differences in perception, knowledge, awareness, and attitude with regard to environmental problems between educated and community groups and to identify human-dimension factors to improve public perception, knowledge, awareness, and attitude in relation to global environmental conservation concerns in developing countries. Educated and community groups in Jakarta were interviewed, and data obtained from a total of 537 males aged 30-49 years were analyzed. The data were evaluated by the chi-squared test and logistic regression was applied after factor analysis. The results show that: (1) The perception, knowledge, awareness, and attitude of educated subjects in regard to regional and global environmental problems were much better than those of subjects in the community group; (2) The highest 'yes' response in the community group was in regard to perception of AIDS (82.9%). Few subjects in the community group knew the effects and the cause or source of environmental problems, however, they were well informed about AIDS (86.4% for effects and 93.9% for cause or source). The conclusions are: (1) subjects in the educated group had better perception, more detailed knowledge, were more aware, and had better attitudes in regard to regional and global environmental problems than those in the community group; (2) more education is needed to develop environmental actions and ethics in developing countries; (3) non-formal environmental education through popular mass media should be used more widely and frequently, and more detailed information on the environment should be provided to literate people by newspapers and other means. 相似文献
3.
Regional Environmental Change - Vegetation change and soil erosion are among the most serious environmental issues associated with the current the war in Syria. About 13 million people have been... 相似文献
4.
Regional Environmental Change - Mountain ecosystems provide key services to a large portion of the population in the tropics. However, they are particularly vulnerable to regional environmental... 相似文献
6.
Being located in an urban-coastal coupled system, the Hashtpar City is one of the most attractive areas for urban construction, tourism, agricultural activities and environmental protection in northern Iran. To resolve the issues between land developers and environmental conservation agencies, we conducted a scenario-based urban growth allocation procedure through the SLEUTH model. The scenarios consisted of ‘business as usual’, ‘managed urban growth’ and ‘environmentally sound growth’ that were introduced by modification of model parameters and exclusion layer. The resultant urban growth arrangements were compared for composition and configuration attributes of landscape patterns. According to the results, the pattern of urbanized lands under managed urban growth option demonstrated better connectivity and compactness of urban patches, while the two other scenarios generated a highly fragmented pattern. The managed urban growth can be considered as a compromised solution between other scenarios since it simultaneously takes into accounts both developers and environment protectors points’ of views. On this basis, a combination of centralized and decentralized urban land use planning is a recommended strategy for our urban-coastal environment to fulfill the purposes of a sustainable development process. The findings of the present article suggest that further expansion of the major urban core in the targeted area should be prohibited since it can lead to an urban patch with considerable physical size and noticeable ecological footprint. 相似文献
8.
In this study, we investigate whether traditional swidden agriculture on nutrient-poor tropical soils can sustainably support a growing indigenous population within Manu National Park, Peru. Based on interviews with 50 Matsigenka farmers, as well as GPS mapping and field visits, we established the location and size of all 124 swidden gardens cultivated in 2000 and 2001. Using a GIS-based soil map of Manu Park, we identify the total extent of potential arable land (1) throughout the park zones currently available for Matsigenka habitation, and (2) within the vicinity of the two study communities. Taking into account current per capita garden size, cultivation and fallow practices, we calculate the maximum human carrying capacity of swidden agriculture for (1) all available park zones and (2) the immediate vicinity of the two current communities. Even given the second, highly limited scenario, the sustainable human carrying capacity is estimated to be 2,138 individuals, which is far higher than the current population of about 420 people. Thus, arable land does not appear to be a limiting factor for the growth of the indigenous population in Manu Park at the current time. Other possible limiting factors for population growth are identified and discussed. We conclude that a conservation policy of population stabilization around the current settlements is viable in that it will not result in reduced resource availability over the next few decades, and that the challenge is to identify and mitigate the forces causing population fissioning and spread. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
9.
Based on a feasibility study, we have recently proposed a multivariate regression model for the impact of air pollution on the mortality of a long-term exposed population. This article proceeds by providing some experimental results, since this model has been fitted to data on a cross sectional basis for 41 census tracts in the Munich metropolitan area. The results obtained so far could be supportive to more detailed epidemiological studies of air pollution which have been conducted in many industrial countries; unfortunately, only relatively few have been conducted in West Germany. 相似文献
10.
Maintaining and enhancing ecosystem services through the restoration of degraded ecosystems have become an important biodiversity conservation strategy. Deciding where to restore ecosystems for the attainment of multiple services is a key issue for future planning, management, and human well-being. Most restoration projects usually entail a small number of actions in a local area and do not consider the potential benefits of planning restoration at broad regional scales. We developed a hierarchical priority setting approach to evaluate the performance of restoration measures in a semiarid basin in NE Spain (the Martín River Basin, 2,112 km 2). Our analysis utilized a combination of erosion (a key driver of degradation in this Mediterranean region) and six spatially explicit ecosystem services data layers (five of these maps plotted surrogates for soil retention and accumulation, water supply and regulation, and carbon storage, and one plotted a cultural service, ecotourism). Hierarchical maps were generated using a geographic information system that combined areas important for providing a bundle of ecosystem services, as state variables, with erosion maps, as the disturbance or regulatory variable. This was performed for multiple scales, thereby identifying the most adequate scale of analysis and establishing a spatial hierarchy of restoration actions based on the combination of the evaluation of erosion rates and the provision of ecosystem services. Our approach provides managers with a straightforward method for determining the spatial distribution of values for a set of ecosystem services in relation to ecological degradation thresholds and for allocating efforts and resources for restoration projects in complex landscapes. 相似文献
11.
This article describes a study of the environmental impacts of the use of industrial agricultural chemicals in four Asian
countries—China, India, the Philippines and Thailand. The objective was to contribute objectively to the discussion on the
extent of the problem, past and current damages to the environment to and outline possible paths to sustainable and environmentally
benign agriculture. The four countries are experiencing rapid economic growth under a tremendous population growth pressure
that, with the exception of China, will continue without leveling of in a foreseeable future. This requires more food production
that has been accomplished by the increased use of industrial chemical fertilizers. Although the four countries uses of industrial
chemicals vary, the mix of nutrients appears to be imbalanced, resulting in large nitrogen losses into the environment, especially
in China. A suggested solution of the problem begins with reducing (China) or maintaining (India, the Philippines, Thailand)
average nutrient application levels needed by the crops and includes optimal hybrid agriculture by using organic fertilizers,
and fertilizers in the irrigation water already overloaded with nitrogen. There is a need to balance fertilizer N and P applications
with the crop needs. 相似文献
12.
Mining has become one of the main causes of increased heavy metal loading of river systems throughout the world. There is however an evident gap between assessments of soil contamination and metal release at the mined sites and estimates of river pollution. The present work focuses on Zaamar Goldfield, which is one of the largest placer gold mines in the world, located along the Tuul River, Mongolia, which ultimately drains into Lake Baikal, Russia. It combines field observations in the river basin with soil erosion modelling and aims at quantifying the contribution from natural erosion of metal-rich soil to observed increases in mass flows of metals along the Tuul River. Results show that the sediment delivery from the mining area to the Tuul River is considerably higher than the possible contribution from natural soil erosion. This is primarily due to excessive mining-related water use creating turbid wastewaters, disturbed filtering functions of deposition areas (natural sediment traps) close to the river and disturbances from infrastructures such as roads. Furthermore, relative to background levels, soils within Zaamar Goldfield contained elevated concentrations of As, Sr, Mn,V, Ni, Cu and Cr. The enhanced soil loss caused by mining-related activities can also explain observed, considerable increases in mass flows of metals in the Tuul River. The present example from Tuul River may provide useful new insights regarding the erosion and geomorphic evolution of mined areas, as well as the associated delivery of metals into stream networks. 相似文献
13.
Environment, Development and Sustainability - Even though ecosystem services have a significant contribution to human well-being, their value is not always recognized. Despite difficulties, the... 相似文献
14.
Soil erosion in many parts of the developing world poses a threat to rural livelihoods, to the sustainbility of the agricultural
sector, and to the environment. Most erosion prediction models are mechanistic and unsuited to quantify the severity of soil
erosion in a data-limited developing world context. The model developed in this paper for Negros Island, in the central Philippines,
is based on the Revised Universal Soil Loss Equation, but contains important innovations such as the movement of eroded soil
over the landscape, simulating deposition on lower slopes and in waterways. It also includes a term describing farmer strategies
to reduce soil erosion, which are typically ignored in erosion prediction models. A two-sample t-test found that model-predicted sediment loading values were not significantly different from field-measured sediment loading
values when corrected for watershed size ( P = 0.857). The model predicts an annual loss of 2.7 million cubic meters of sediment to waterways such that by 2050 more than
416,000 ha of agricultural land will be rendered unproductive due to erosion. Farmer behavior conserves soil, but on the steepest
slopes soil conservation practices are not adequate to prevent erosion. Of two proposed strategies to control soil erosion
in the rural Philippines, the model suggests that a complete switch to tree crops would conserve more soil than universal
terrace adoption. However, even under these conservation scenarios, erosion threatens the areal extent of upland agriculture
on Negros, and hence the sustainability of the island’s food supply.
相似文献
15.
The impact of soil filtered runoff from a section of the M25 outer London motorway (constructed in 1981) on a pond, wetland and stream in a nature reserve was investigated by monitoring water, sediment. The tissues of the emergent plants Typha latifolia and Glyceria maxima collected from the pond were analysed for the heavy metals, Cd, Pb, Cu and Zn. Macroinvertebrates were monitored in the stream and biotic indices applied to the data. The plant tissue concentrations for Typha and Glyceria show decreasing metal concentrations from root to rhizome to leaf. This trend has previously been reported for Typha exposed to runoff although the tissue concentrations are lower in this study with the exception of Cd in root tissue. The Biological Monitoring Working Party (BMWP) score and Average Score Per Taxon (ASPT) for the stream at sites above and below the pond outlet are lower than the scores recorded by the Environment Agency for England and Wales at an upstream site above the Pond/Wetland. The sites have an Overall Quality Index of 'moderate water quality', and there is no evidence of a deterioration of biologically assessed water quality between them. The results of the study show the long-term impact on sediment of filtered road runoff discharges to a natural wetland and pond located in a nature reserve. The use of natural wetlands for the discharge of road runoff is inadvisable. Constructed wetlands in combination with other structures including settlement trenches and ponds should be considered as an alternative treatment option. 相似文献
16.
ObjectiveEstimate the health risks and benefits of mode shifts from car to cycling and public transport in the metropolitan area of Barcelona, Spain. MethodsWe conducted a health impact assessment (HIA), creating 8 different scenarios on the replacement of short and long car trips, by public transport or/and bike. The primary outcome measure was all-cause mortality and change in life expectancy related to two different assessments: A) the exposure of travellers to physical activity, air pollution to particulate matter < 2.5 μm (PM2.5), and road traffic fatality; and B) the exposure of general population to PM2.5, modelling by Barcelona Air-Dispersion Model. The secondary outcome was a change in emissions of carbon dioxide. ResultsThe annual health impact of a shift of 40% of the car trips, starting and ending in Barcelona City, to cycling (n = 141,690) would be for the travellers who shift modes 1.15 additional deaths from air pollution, 0.17 additional deaths from road traffic fatality and 67.46 deaths avoided from physical activity resulting in a total of 66.12 deaths avoided. Fewer deaths would be avoided annually if half of the replaced trips were shifted to public transport (43.76 deaths). The annual health impact in the Barcelona City general population (n = 1,630,494) of the 40% reduction in car trips would be 10.03 deaths avoided due to the reduction of 0.64% in exposure to PM2.5. The deaths (including travellers and general population) avoided in Barcelona City therefore would be 76.15 annually. Further health benefits would be obtained with a shift of 40% of the car trips from the Greater Barcelona Metropolitan which either start or end in Barcelona City to public transport (40.15 deaths avoided) or public transport and cycling (98.50 deaths avoided).The carbon dioxide reduction for shifting from car to other modes of transport (bike and public transport) in Barcelona metropolitan area was estimated to be 203,251 t/CO 2 emissions per year. ConclusionsInterventions to reduce car use and increase cycling and the use of public transport in metropolitan areas, like Barcelona, can produce health benefits for travellers and for the general population of the city. Also these interventions help to reduce green house gas emissions. 相似文献
18.
The radioactivity level of soils in a volcanic area in Cameroon was determined and discussed. Thirty soils samples were collected from Buea and Limbé cities located in the south-western Cameroon. These two regions are known for theirs volcanic grounds due to the presence of Mount Cameroon Mountain. The activity concentrations of natural radionuclides as well as that of the fission product were evaluated by gamma-ray spectrometry using a hyper-purity germanium detector (HPGe). The ranges of concentrations in the surveyed soils were 11-17 Bq kg(-1), 22-36 Bq kg(-1) and 43-201 Bq kg(-1) for (226)Ra, (232)Th and (40)K, respectively. The radioisotope (137)Cs was also found but in a very small amount. The outdoor absorbed dose rate 1m above ground with the corresponding annual effective dose rate, assuming a 20% occupancy factor was estimated. The radium equivalent and the external hazard index were also evaluated and results are compared with available data from other studies and with the world average value [United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), 1988. Sources, Effects and Risks of Ionizing Radiation. Report to the General Assembly on the Effects of Atomic Radiation. United Nations, New York; UNSCEAR, 2000. Sources and Effects of Ionizing Radiations. Report to the General Assembly with Scientific Annexes. United Nations, New York]. A solid state nuclear track detector (SSNTD), LR-115 was used for soil radon measurements at a depth of 50 cm. The ranges of soil radon concentrations were 6.7-10.8 kBq m(-3) and 5.5-8.7 kBq m(-3) in Buea and Limbé, respectively. A positive correlation was found between concentrations of radium measured with gamma-spectrometry and the soil radon concentrations measured with the nitrate cellulose detectors. The results of this study provide the radioactivity level in soil of a volcanic area, which has been found to be within the safety limits. The south-western Cameroon can be considered as having normal natural background radiation. 相似文献
19.
Accelerated erosion and soil degradation currently cause serious problems to the Oued El Maleh basin (Morocco). Furthermore, there is still only limited information on rates of soil loss for optimising strategies for soil conservation.In the present study we have used the (137)Cs technique to assess the soil erosion rates on an agricultural land in Oued el Maleh basin near Casablanca (Morocco). A small representative agricultural field was selected to investigate the soil degradation required by soil managers in this region. The transect approach was applied for sampling to identify the spatial redistribution of (137)Cs. The spatial variability of (137)Cs inventory has provided evidence of the importance of tillage process and the human effects on the redistribution of (137)Cs. The mean (137)Cs inventory was found about 842 Bq m(-2), this value corresponds to an erosion rate of 82 tha(-1) yr(-1) by applying simplified mass balance model in a preliminary estimation. When data on site characteristics were available, the refined mass balance model was applied to highlight the contribution of tillage effect in soil redistribution. The erosion rate was estimated about 50 tha(-1) yr(-1). The aspects related to the sampling procedures and the models for calculation of erosion rates are discussed. 相似文献
20.
Understanding the dynamics of society’s physical exchange processes with the environment (society’s metabolism) is a major theme of long-term socioecological research. In this paper, we adapt the concept of socioecological metabolism to analyze the competition between gunpowder production and agriculture for nitrogen (N) in the pre-industrial agro-ecosystem of Pamhagen in the late eighteenth century. Saltpeter (KNO 3)—the main ingredient of gunpowder—was chemically refined from agricultural waste products, in particular manure and wood ash, which were vital for the maintenance of soil fertility. In this paper, we reconstruct nitrogen flows in the agro-ecosystem of Pamhagen and establish a nutrient balance, which allows assessing the impact of saltpeter production on agricultural soil fertility management. We find that nitrate extracted by saltpeter production in our case study was equivalent to 23 % of the total available nitrogen in manure in 1778 and 12 % in 1780. The growing demand for gunpowder and thus the artisanal production of saltpeter became influential drivers in the management of societal nitrogen flows on the local level, competing over key resources for sustaining soil fertility and leaving a substantial imprint on the nutrient budget of agricultural soils as less nitrogen was available for plant uptake. 相似文献
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