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961.
Improved understanding of temporal and spatial Phosphorus (P) discharge variations is needed for improved modelling and prioritisation
of abatement strategies that take into account local conditions . This study is aimed at developing modelling of agricultural
Phosphorus losses with improved spatial and temporal resolution, and to compare the accuracy of a detailed process-based model
with a rainfall-runoff coefficient-based model. The process-based SWAT model (Soil and Water Assessment Tool) was implemented
for five river basins in central Sweden, and results compared with the rainfall-runoff coefficient-based model WATSHMAN (Watershed
Management System) for one of these river basins. Parameter settings and attribute values were adapted to Scandinavian soil
conditions, crops and management practices. Model performance regarding flow dynamics was overall satisfactory. Comparable
results were achieved at several scales. The modelled P load was of high accuracy for the days when monitoring data were available
for validation, generally once a month. Modelled monthly P load did not fit as well with averaged monthly monitoring load
values, mainly since monthly monitoring often partly or entirely misses the peak flows. The comparison of SWAT and WATSHMAN
gave slightly better results for the process-based model (SWAT). Better spatial resolution for input data such as Soil-P content
and agricultural management practices will be required to reach modelling results that enable identification of measures adapted
to local conditions. 相似文献
962.
当今世界电子、电器工业快速发展,层出不穷的技术创新与持续膨胀的市场需求加速了电子与电器设备的更新换代,产生了大量的电子与电器废弃物(WEEE).鉴于WEEE所带来的严重的环境问题及其所含有的金属、贵金属、塑料及玻璃等高利用价值的材料,对WEEE进行资源化再循环处理已成为人们关注的热点.WEEE组成材料在密度、铁磁性、导电性等物理性质方面的较大差异使采用环境友好的机械物理方法对其进行资源化再循环处理成为可能.就WEEE拆解及其所含物质机械物理分离研究进展进行了综述. 相似文献
963.
Agricultural causes of desertification risk in Minqin, China 总被引:1,自引:0,他引:1
This study uses statistical modeling techniques to develop a desertification risk index (RI) for Minqin County, Gansu Province, China. Twenty socio-economic factors were selected and compared with the RI results to explore the spatial and temporal variability of desertification risk in the study area and to identify possible local driving forces behind desertification risk. The explanatory factors were different in 1988, 1992 and 1997, possibly reflecting the role of temporal variation as a contributor to desertification. The average number of sheep per-household was found to be an important indicator of change in desertification risk, while changes in ridge crop planting area explained the distribution of the rate of change in desertification risk in 1988-1992. The results suggests that the RI was useful in expanding the understanding of spatial temporal desertification issues in Minqin County, as well as identifying a current set of agricultural activities related to desertification risk. Further, given the limited nature of consistent data and observations for the area, development of the RI also served to establish a baseline for future investigations into desertification change and the risks such change might pose for the region. 相似文献
964.
Calvo-Iglesias MS Fra-Paleo U Crecente-Maseda R Díaz-Varela RA 《Environmental management》2006,38(6):921-933
The aim of this work is the analysis of the dynamics in cultural landscapes, focused on the spatial distribution of changes
in land cover and landscape patterns, and their possible linkages. These dynamics have been analyzed for the years 1957 and
2000 in a sector of the north of Galicia (NW Spain) characterized with diverse landscapes. Afforestation processes linked
to agriculture abandonment and forestry specialization were the main processes observed in the study area, with the exception
of the southern mountainous sector that was dominated by ploughing of scrubland for conversion into grassland, reflecting
a specialization in livestock production. The structural changes that have taken place in most of the study area were related
to the heterogeneity aspects, although the mountainous sectors were characterized by changes in heterogeneity and fragmentation.
According to the tests performed, the comparison of the spatial distribution of both dynamics showed a certain statistical
significance, reflecting the interrelationship between patterns and processes. This approach could be useful for the identification
of areas with similar characteristics in terms of spatial dynamics so as to define more effective and targeted landscape planning
and management strategies. 相似文献
965.
The management of plastic waste through various methods such as landfilling, recycling, and incineration has several inherent shortcomings, such as a lack of resources, preparation, motivation, financial power, and expertise. Additionally, these methods are unable to handle the quantity and types of plastic waste, nor do they increase the public's interest in plastic waste management practices. According to research, environmental, economic, and social factors are the main drivers for reducing plastic waste. Experts from around the world have identified four significant areas of concern for which solutions have been proposed: methods of plastic waste reduction and management, the amount of plastic waste, the quality of waste/plastic, and awareness of plastic waste management/cost of plastic waste management. However, individual solutions proposed for these key areas of concern are facing several challenges, leading to delays in their adoption or less popularity globally. The review has identified the reasons for the less popularity of existing plastic waste management methods, which are less environmentally friendly and have a complex process, hence requiring serious reconsideration from technocrats and researchers to develop more sustainable and efficient procedures that do not produce more hazardous by-products. This study also found that financial incentives are one of the main drivers to ensure the mass participation of lower and working-class people. 相似文献
966.
介绍了一种革取技术,可在生产过程中处理印制线路板生产的碱性蚀刻废液,使之脱铜后再生,实现碱性蚀刻废液的循环使用;运用反革取技术使苹取剂复活循环使用;反革取提取到的硫酸铜经电解为电解铜,电解液可循环使用。 相似文献
967.
968.
969.
The EU Water Framework Directive (WFD) requires member states to take measures to ensure that bodies of water will be in good chemical and ecological condition by 2015. Important measures to achieve this goal include reducing emissions of nitrogen (N) and phosphate (P2O5) from manure and mineral fertilizers into the environment. In regions with a high livestock density, this measure is expected to affect agricultural production and income. To quantify these effects, an environmental economic model is required that can assess alternatives capable of reducing N and P2O5 potential emissions to water. In this paper, we develop a model that is capable of analysing changes in potential emissions to water of N and P2O5 and apply it to the Netherlands, a country with large nutrient emissions. Compared to a 2015 reference scenario based on current efforts to reduce nutrient emissions, we found that the WFD measures will increase regional transport and export of manure and reduce the number of animals in the Netherlands. Fodder adjustments (defined as lower N and P2O5 input in purchased fodder) to decrease nutrient excretion in manure were a less attractive option than amongst others export, transportation of manure to another region, land use changes or reduction of the number of livestock. Compared to the reference scenario in 2015, total agricultural income will decrease by about €81.5 million per year (about €49/ha per year), although the effects will differ among parts of the Netherlands and agricultural sectors. The average predicted decrease in N emissions from agricultural sites, vulnerable to leaching into bodies of water will be almost 20% or approximately 14.7 kg N/ha per year. The reduction in N emissions to air from animal sheds, manure storage systems, application of animal manure and mineral fertilisers to the crops and grazing animals equals 6.5% or 5 kg ammonia (NH3) per hectare. 相似文献
970.
对采用全部氧化分步还原方法从废旧镍氢电池中回收氯化镍和氯化钴产品进行较系统的研究,确定了该方法的工艺参数,并根据实验数据进行投入产出估算。 相似文献