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1.
Summary This study assessed the contribution of an oil seed industry to the organic loadings of an urban atmosphere, so that more realistic strategies can be developed to control such pollution. Emission measurements suggest that fatty acids, aldehydes and solvent related hydrocarbons are emitted in amounts comparable to or even exceeding anthropogenic organics. Technological options for controlling emissions in the context of the local situation with the data presented are discussed.Paolo Battistoni was born in Ancona, Italy in 1951 and received a degree in chemistry in 1974 at Bologna University. He started his activity at Ancona University where he is a permanent professor of waste water treatments. His research interests have centered on monitoring of organics in ambient air and waste streams and method developments in these areas.Gabriele L. Fava was born near Bologna, Italy in 1945 and received his degree in chemistry from the University of Bologna in 1972. He started his research activity at Ancona University where he is a permanent professor of pollution and environmental control. He has spent research terms at the Iowa State University, USA in 1976 and 1979. His main interest is in the environmental behaviour of toxic substances through physicochemical profiles.  相似文献   

2.
Neighbourhoods are increasingly gaining attention as planning units of great potential for contribution to sustainable development. Many assessment tools such as LEED-ND, BREEAM Communities and CASBEE-UD have been developed to examine the sustainability of neighbourhood development projects. Some of these tools are claimed to be suitable for assessment in different contexts, and LEED-ND has already been utilised in various countries. This study investigates the viability of using global standards through a series of comparative case studies. One certified case from each of the aforementioned tools is chosen and evaluated against its non-corresponding assessment tools. Selected cases are, respectively, Hoyt Yards, MediaCityUK and Koshigaya Lake Town. Results of this study provide evidence that casts doubt on the viability of using global standards. The paper concludes that neighbourhood sustainability assessment should be regarded as a pluralistic practice. This implies that any realistic and reliable assessment should take account of the specificities of specific locations and varying needs of different stakeholders.  相似文献   

3.
A multicriteria analysis system was developed for producing risk maps of agricultural pollution due to alternative cultivation systems in the Watershed of the Lagoon of Venice (WLV) in Italy. Results of a field-scale simulation model for agricultural diffuse pollution were used to compile a matrix of environmental impacts, in terms of pollution indices. The most widespread combinations of typical environments (as defined by combinations of soil and climate variables) and alternative land uses (types of crops and cultivation systems) were described in the impact matrix. Land use in terms of crop distribution was based on census data. Two alternative cultivation systems were defined on the basis of the recent changes to the European Common Agricultural Policy: ordinary and eco-compatible. The effects of alternative scenarios were evaluated in terms of pollution risks for water resources. The evaluation procedure was built into the framework of a geographical information system to take into account the spatial features of pollution phenomena, vulnerability of the land and risk for water resources. The results demonstrated the great potential of eco-compatible practices for reducing the risks for surface and groundwater (−15 and −50%, respectively).  相似文献   

4.
Agricultural systems around the world are being severely impacted by changing climate, extreme weather events, urbanisation and neo-liberal (free market) policies. Yet, there are currently few studies on the experiences of those affected by these compounding pressures captured at the local scale. Experiences of adaptive responses – along with recommendations for transformations of the agricultural systems provided by those working in local-level settings – have also not been captured. Yet, such responses provide valuable insights into what can be done, and what needs to be done, to bring about a more equitable and sustainable food system. In this paper, we draw upon the opinions and experiences of those involved in food production and distribution in the historically abundant, peri-urban, region of the Mary Valley, Queensland, Australia. Underpinning the practical and strategic recommendations made by participants is a need for supermarket and government policies to appropriately reflect the immense value of small-scale farmers in sustaining rural communities and enhancing the resilience and sustainability of Australia’s food security. Importantly, our participants in this case study location reiterate that the impacts of climate change are manageable if the farming business is able to generate enough profit to absorb the costs of preparation and recovery from disasters.  相似文献   

5.
Amidst the hue and cry about anthropogenic sources of pollution, there are regions in the world facing silent metal discharges purely due to geochemical factors. The present investigation relates to such a situation and deals with the non-anthropogenic discharge of cadmium into the local environment. The phosphorite rocks of the Roorkee area of India contain cadmium and, particularly as these are used in the manufacture of superphosphate, the rocks could lead to the large-scale disbursement of cadmium into the open environment. The area under study has soil rich in cadmium-containing minerals, as a result of which water is likely to leach out mobile cadmium and the ground water and crops could become contaminated. This is evident from the high values of cadmium in the tap water and food samples in the area. The Ganga and the Yamuna, the two major rivers traversing the area that originate in the central crystalline rocks of the Himalayas, show high cadmium values at Rishikesh and Dakpathar. Moreover, the sediments of these rivers have cadmium in easily bioavailable form. Food samples and milk analysed from the area show, in some cases, cadmium levels above the safety limits. This high exposure to cadmium is probably causing ailments so far unreported.  相似文献   

6.
Assessing the accuracy of agronomic and water quality simulation models in different soils, land-use systems, and environments provides a basis for using and improving these models. We evaluated the performance of the ADAPT model for simulating riverine nitrate-nitrogen (NO3-N) export from a 1500-km2 watershed in central Illinois, where approximately 85% of the land is used for maize-soybean production and tile drainage is common. Soil chemical properties, crop nitrogen (N) uptake coefficient, dry matter ratio, and a denitrification reduction coefficient were used as calibration parameters to optimize the fit between measured and simulated NO3-N load from the watershed for the 1989 to 1993 period. The applicability of the calibrated parameter values was tested by using these values for simulating the 1994 to 1997 period on the same watershed. Willmott's index of agreement ranged from 0.91 to 0.97 for daily, weekly, monthly, and annual comparisons of riverine nitrate N loads. Simulation accuracy generally decreased as the time interval decreased. Willmott's index for simulated crop yields ranged from 0.91 to 0.99; however, observed crop yields were used as input to the model. The partial N budget results suggested that 52 to 72 kg N ha(-1) yr(-1) accumulated in the soil, but simulated biological N fixation associated with soybeans was considerably greater than literature values for the region. Improvement of the N fixation algorithms and incorporation of mechanisms that describe soybean yield in response to environmental conditions appear to be needed to improve the performance of the model.  相似文献   

7.
Use of amines is one of the leading technologies for post-combustion carbon dioxide capture from gas and coal-fired power plants. This study assesses the potential environmental impact of emissions to air that result from use of monoethanol amine (MEA) as an absorption solvent for the capture of carbon dioxide (CO2). Depending on operation conditions and installed reduction technology, emissions of MEA to the air due to solvent volatility losses are expected to be in the range of 0.01–0.8 kg/tonne CO2 captured. Literature data for human and environmental toxicity, together with atmospheric dispersion model calculations, were used to derive maximum tolerable emissions of amines from CO2 capture. To reflect operating conditions with typical and with elevated emissions, we defined a scenario MEA-LOW, with emissions of 40 t/year MEA and 5 t/year diethyl amine (DEYA), and a scenario MEA-HIGH, with emissions of 80 t/year MEA and 15 t/year DEYA. Maximum MEA deposition fluxes would exceed toxicity limits for aquatic organisms by about a factor of 3–7 depending on the scenario. Due to the formation of nitrosamines and nitramines, the estimated emissions of DEYA are close to or exceed safety limits for drinking water and aquatic ecosystems. The “worst case” scenario approach to determine maximum tolerable emissions of MEA and other amines is in particular useful when both expected environmental loads and the toxic effects are associated with high uncertainties.  相似文献   

8.
To devise and implement strategies to manage the quality of urban air, a metropolis needs air pollution data on which an air quality management plan can be formulated. Although air pollutants can come from several sources, many reports suggest that nitrogen dioxide from motor vehicle emissions is the major contributor to air pollution in cities. Since vehicles stop or move slowly through traffic intersections, concentrations of nitrogen dioxide (NO(2)) are expected to be relatively high at these sites. Inexpensive Ogawa passive samplers were placed at selected traffic intersections in the Durban Metropolis to trap the NO(2) which was then analysed by a sensitive laboratory-based method. The data obtained by this method was compared with data from sophisticated system comprising an active sampler cum on-line chemiluminescence detector. The sampling was done over a twelve month period to cover all seasons. Statistical analysis of the data showed that there was no significant difference between the means for the two methods. This study has established that an Ogawa passive sampler may be used as an economical and reliable collector for NO(2) in ambient air under varying climatic conditions. Further, the analysis method using a UV-Visible spectrophotometer was sensitive enough to detect NO(2) at the 10-20 ppb level. The cost of the method should be well within the budgets of most municipalities and it would motivate them to develop policies to alleviate traffic congestion.  相似文献   

9.
Ground-level area sources, such as those associated with the use of agricultural fumigants, waste disposal sites, wastewater lagoons, and other applications, present a challenge in terms of characterizing atmospheric flux as a function of time. Studies are costly in terms of field activities and laboratory analysis. The optimization of field study design, therefore, is essential to conduct cost-effective research. The collection of on-field profile data for airborne concentration, wind speed, and wind direction can be used in conjunction with the integrated horizontal flux (IHF) method to empirically compute complex source terms as a function of time. This paper focuses on complicating factors and field study design issues for the use of the IHF method. Insights and examples are drawn from five field research studies. The methods and results of characterizing the uncertainty and method precision in the emission fitting for the IHF method also are presented.  相似文献   

10.
Leachate from waste disposal sites (WDS) can significantly affect the soil physical, chemical and biological qualities, reducing soil health and agricultural productivity. However, there is a paucity of data on soil quality for understanding soil health impact due to WDS in Uganda. This study's aim was to understand, using the Kiteezi landfill site, how WDS impact soil properties. Soil samples were collected over 4 months in and around the landfill from three locations, and the soil quality data of the nearby area were used as baseline data for assessing the impact on soil due to WDS in the area. There were significant increases in the concentration of all studied parameters at the landfill except total N. The concentrations of ammonium (14.84 ± 1.76 mg/kg), nitrate (127.96 ± 18.36 mg/kg), and pH (7.8) were above the optimum levels. The levels of available P (181.4 ± 28.9 mg/kg) and exchangeable bases; K (2.23 ± 0.24 mg/kg), Na (1.17 ± 0.14 mg/kg), Mg (3.35 ± 0.3 mg/kg) and Ca (14 ± 1.1 mg/kg) cmol (+)/kg were optimal for plant growth. The calculated CEC of 20.75 cmol (+)/kg) showed that soils have a good potential to supply plant nutrients. Heavy metal levels were still below the permissible limit. Hence, the study shows that although WDS may contribute to the increase of soil fertility, they can potentially reduce the overall productivity of soil by increasing nutrient levels beyond optimum levels.  相似文献   

11.
12.
Agricultural land use can place heavy demands on regional water resources, strongly influencing the quantity and timing of water flows needed to sustain natural ecosystems. The effects of agricultural practices on streamflow conditions are multifaceted, as they also contribute to the severity of impacts arising from other stressors within the river ecosystem. Thus, river scientists need to determine the quantity of water required to sustain important aquatic ecosystem components and ecological services, to support wise apportionment of water for agricultural use. It is now apparent that arbitrarily defined minimum flows are inadequate for this task because the complex habitat requirements of the biota, which underpin the structure and function of a river ecosystem, are strongly influenced by predictable temporal variations in flow. We present an alternative framework for establishing a first-level, regional ecological instream flow needs standard based on adoption of the Indicators of Hydrologic Alteration/Range of Variability Approach as a broadly applicable hydrological assessment tool, coupling this to the Canadian Ecological Flow Index which assesses ecological responses to hydrological alteration. By explicitly incorporating a new field-based ecological assessment tool for small agricultural streams, we provide a necessary verification of altered hydrology that is broadly applicable within Canada and essential to ensure the continuous feedback between the application of flow management criteria and ecological condition.  相似文献   

13.
The present study evaluated the possibility of using the sludge produced by a vegetable-processing factory in agriculture. The sludge was amended with a soil mixture (i.e., a mixture of sand, soil, and manure) and was applied at 0, 165, 330, 495 and 660 t/ha to promote the growth of cucumbers. The effects of various sludge loadings on plant growth were assessed by counting plants and leaves, measuring stem lengths, and weighing the green parts and roots of the plants. We also compared heavy metal uptake by the plants for sludge loadings of 330, 495, and 660 t/ha with various recommended standards for vegetables. Our results showed that plant growth patterns were influenced to some extent by the sludge loadings. In general, the number of leaves, stem length, and dry weight of green parts exhibited a pronounced positive growth response compared with an unfertilized control, and root growth showed a lesser but still significant response at sludge loadings of 165 and 330 t/ha. The sludge application caused no significant increase in heavy metal concentrations in the leaves, though zinc (Zn) and iron (Fe) were found at elevated concentrations. However, despite the Zn and Fe accumulation, we observed no toxicity symptoms in the plants. This may be a result of cucumber's tolerance of high metal levels.  相似文献   

14.
Five major management goals were identified for the upper Grande Ronde River Basin on the Wallowa-Whitman National Forest in northeastern Oregon: to produce high-quality fish habitat, to maintain elk habitat, to restore and maintain forest conditions within the natural range of viability, and to contribute to community economic stability. From the broad goals, specific goals for stream temperature, habitat effectiveness index (HEI), habitat corridors, maintenance of land in late or old seral stages, and a nondeclining even flow of timber were selected. A case study was undertaken in a small watershed that is under typical societal constraints to determine whether one decisionsupport tool, SNAP II+, could evaluate the selected goals in a single planning exercise. Three riparian management strategies and two forest road scenarios were used. The exclusion of harvest and road-building from riparian zones in order to increase habitat protection decreased harvest levels and net present value but maintained preactivity stream temperatures. Other resources were generally maintained within prescribed management levels. Although the technique has limitations (e.g., it does not account for riparian zones in calculations of forage and cover for HEI, and it can use the maximum but not minimum acreage goal for some resources), it shows promise for evaluating management tradeoffs in watershed analysis.This is Paper 3069 of the Forest Research Laboratory, Oregon State University, Corvallis, Oregon.  相似文献   

15.
In semi-arid valleys of southwestern China, seasonal shortage of water is the major contributing factor to low and unstable crop yield. Harvesting of both rainwater and brooklets water in the semi-arid valleys of Ningnan county of Sichuan Province has brought about considerable economic and environmental change. Brooklet water is collected throughout the year but mainly during the rainy season in a series of ponds while rainwater is harvested in underground tanks constructed on road side or land boundaries with only a small opening above ground to save limited cropland. Increased water availability has promoted cultivation of sugarcane, tobacco, and mulberry, and increased per unit area yield of food crops. Sericulture, sugarcane and tobacco have become three important sources of farmers' income. The water harvesting has contributed considerably to increased rural income, poverty reduction, reduced soil erosion and improvement in overall environment. Government has played a key role in planning and implementation of water harvesting programmes. Financial support of government and clear ownership of water harvesting facilities are critical for the success of the programme. Application of similar water harvesting techniques in other areas with similar biophysical conditions would contribute to enhancing the rural economy and alleviating poverty.  相似文献   

16.
Records in public archives were evaluated for the period 1981-1991. Simple surveys of peoples and of technology and physical premises provided insight to gauge the attitudes of a local community in the Melbourne municipality and the Melbourne City Council towards composting of organic waste materials. There is a lag in perception and attitudes between the local community and the local government towards composting of organic refuse as a solid waste treatment option. The simple methodology of the study still made it possible to verify past and present perceptions and attitudes.  相似文献   

17.
The valuation of historical sites: a case study of Valdivia,Chile   总被引:1,自引:0,他引:1  
The economic valuation of cultural heritage is an area of increasing interest and an important research topic in the emerging field of cultural economics. Many services and values associated with cultural heritage are not traded in markets, and their estimation requires methods developed for the valuation of non-market goods, such as those used in environmental economics. This paper applies the contingent valuation method with double dichotomous choice to estimate the value of historical sites in the city of Valdivia, Chile. The valuation exercise was implemented by designing a hypothetical guided walking tour to a cluster of historical sites in the city centre, and surveying tourists visiting the city during the summer of 2004. Parametric and non-parametric statistical methods were used to estimate the survival distribution and the mean and median estimates of the willingness-to-pay (WTP). The study emphasizes the importance of explicitly treating heterogeneous preferences and the sensitivity of the survival distribution to the estimation methods used.  相似文献   

18.
Controlled drainage and wetlands could be very effective practices to control nitrogen pollution in the low-lying agricultural plains of northeast Italy, but they are not as popular as in other countries. An experiment on lysimeters was therefore carried out in 1996-1998, with the double aim of obtaining local information to encourage the implementation of these practices and to gain more knowledge on the effects involved. Controlled drainage + subirrigation and wetlands were all considered as natural systems where alternative water table management could ameliorate water quality, and were compared with a typical water management scheme for crops in the open field. Eight treatments were considered: free drainage on maize (Zea mays L.) and sugarbeet (Beta vulgaris L.), two treatments of controlled drainage on the same crops, and five wetland treatments using common reed [Phragmites australis (Cav.) Trin. ex Steud.], common cattail (Typha latifolia L.), and tufted sedge (Carex elata All.), with different water table or flooding levels. Lysimeters received about 130 g m 2 of N with fertilization and irrigation water, with small differences among treatments. The effects of treatments were more evident for NO3-N concentrations than for the other chemical parameters (total Kjeldahl nitrogen, pH, and electrical conductivity), with significantly different medians among free drainage (33 mg L(-1)), controlled drainage (1.6 and 2.6 mg L(-1)), and wetlands (0.5-0.7 mg L(-1)). Referring to free drainage, NO3-N losses were reduced by 46 to 63% in controlled drainage and 95% in the average of wetlands. Wetlands also reduced losses of total dissolved solids from 253 g m(-2) (average of crop treatments) to 175 g m(-2) (average of wetlands).  相似文献   

19.
The impact of agriculture on regional air quality creates significant challenges to sustainability of food supplies and to the quality of national resources. Agricultural emissions to the atmosphere can lead to many nuisances, such as smog, haze, or offensive odors. They can also create more serious effects on human or environmental health, such as those posed by pesticides and other toxic industrial pollutants. It is recognized that deterioration of the atmosphere is undesirable, but the short- and long-term impacts of specific agricultural activities on air quality are not well known or understood. These concerns led to the organization of the 2009 American Chemical Society Symposium titled . An outcome of this symposium is this special collection of 14 research papers focusing on various issues associated with production agriculture and its effect on air quality. Topics included emissions from animal feeding operations, odors, volatile organic compounds, pesticides, mitigation, modeling, and risk assessment. These papers provide new research insights, identify gaps in current knowledge, and recommend important future research directions. As the scientific community gains a better understanding of the relationships between anthropogenic activities and their effects on environmental systems, technological advances should enable a reduction in adverse consequences on the environment.  相似文献   

20.
Supply to electrical pumpsets for irrigation purposes accounts for about 25% of the total electricity sold in India. The number of electrical pumpsets is expected to increase from 8.5 million in 1989–90 to 10.5 million in 1994–95. Low load factors (10–12%) and low densities (1–4 pumpsets/km2) mean large investments for the electric utility in order to supply electricity for irrigation. It is reported that there exists a potential to save at least 10% of the electricity supplied to this sector by means of simple retrofit measures. However, conditions in the field pose constraints to such retrofits. Some of those constraints are highlighted in this paper. It is also suggested that immediate attempts be made to ensure that all new connections are energy efficient. This paper suggests that the additional cost incurred to ensure new energy efficient connections and to maintain retrofit energy efficient pumpsets must be looked on as a necessary cost for energy efficiency.  相似文献   

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