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711.
饮用水水源保护区河流水环境容量计算模型 总被引:6,自引:2,他引:6
基于河流一维水环境容量计算模型,通过水质控制目标分析,引入了饮用水供水水库的水环境容量决定其保护区内河流水质控制目标的概念,提出以水库的水环境容量为其上游保护区内河流段末的水质控制目标,解决了由于河流与湖库的总磷水质标准不一致、水质标准中没有河流总氮指标以及水环境容量计算中河流与湖库水文设计条件不同步等,导致水源保护区内河流的水质控制目标确定困难的问题,建立了针对饮用水水源保护区内河流水环境容量的计算模型和方法,本模型直接表达了饮用水供水水库与其上游河流水环境容量之间的定最关系,体现了2个水域间的连续性和相互作用关系,为实现饮用水供水水库及其上游河流的污染物总量控制提供了可靠的科学依据,应用本模型,计算了正在建设中的老虎潭水库保护区内河流的水环境容量.结果表明,根据老虎潭水库水环境存量,保护区内河流的总氮水环境容量为65.05 t·a-1,现状总氮年入河量应削减33.86 t;总磷水环境容量为5.05 t·a-1,现状条件下尚有2.23 t·a-的剩余水环境容量,文中所提出的建模方法可以推广至水质控制目标不同情况下的连续水域,尤其适用于下游水域水质控制要求高于上游水域的情况,拓展了水环境容量的研究思路和方法. 相似文献
712.
Development based climate change adaptation and mitigation—conceptual issues and lessons learned in studies in developing countries 总被引:3,自引:0,他引:3
Kirsten Halsnæs Jan Verhagen 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):665-684
This paper discusses the conceptual basis for linking development policies and climate change adaptation and mitigation and suggests an analytical approach that can be applied to studies in developing countries. The approach is centred on a broad set of policy evaluation criteria that merge traditional economic and sectoral goals and broader social issues related to health and income distribution. The approach is inspired by institutional economics and development paradigms that emphasise human wellbeing, resource access, empowerment, and the arrived freedoms. It is outlined how indicators of wellbeing can be used to assess policies that integrate development and climate change policy objectives, and this approach is discussed in comparison with other work that rather have been inspired by sustainable development aspects of manmade, natural, and social capital. The experiences and results from case studies of development and climate that have done a first attempt to use human wellbeing indicators are reported and discussed. The studies include work from India, China, South Africa, Brazil, Bangladesh, and Senegal. A number of policy examples in the energy-, food-, and water sectors in these studies have shown up to demonstrate numerous linkages between development policies and climate change. Various analytical tools have been used in the studies including quantitative and qualitative scenario work as well as detailed micro-based analysis. The methodological conclusion that can be drawn from these studies, is that it is possible to apply wellbeing indicators to the more detailed policy assessment, but a link to more general national and regional scenario work is not yet established. 相似文献
713.
Long-term dynamics in land resource use and the driving forces in the Beressa watershed, highlands of Ethiopia 总被引:1,自引:0,他引:1
Land degradation in the Ethiopian highlands is considered to be one of the major problems threatening agricultural development and food security in the country. However, knowledge about the forces driving the long-term dynamics in land resources use is limited. This research integrates biophysical information with socio-economic processes and policy changes to examine the dynamics of land resource use and farmers' livelihoods in the Beressa watershed for over 40 years during the second half of the 20th century. It was found that there have been substantial dynamics in land resource use in the area. The natural vegetation cover has been extensively cleared, although most of the cleared areas have since been replaced with plantations. Grazing land has expanded remarkably at the expense of cropland and bare land. However, the expansion of cropland was minimal over the 43-year period despite a quadrupling of the population density. Yields have not increased to compensate for the reduction in per capita cropland, and the soil quality appears to be not that good. Though the farmers perceived it otherwise, the long-term rainfall pattern has improved. In response to soil degradation, water shortage, socio-economic and policy changes, farmers have tended to gradually change from annual cropping to tree planting and livestock production to cope with the problems of soil degradation, water scarcity and smaller farms. Income diversification through the sale of wood and cattle dung is becoming a major livelihood strategy. Apparently, however, little attention has been paid to investments in soil and water conservation (SWC) and local soil fertility amendments. In particular, increased erosion and related high nutrient losses in sediments, as well as the removal of potentially available soil nutrients through the sale of manure threatens to damage agricultural sustainability in the area. 相似文献
714.
Piyush Kant Pandey Khageshwar Singh Patel Jan Lenicek 《Environmental monitoring and assessment》1999,59(3):287-319
This paper reports the PAHs levels in the atmosphere of an urbanised industrial site of India. A high-resolution capillary gas chromatograph with a mass spectrometric detector (HRCGC-MS) and a high performance liquid chromatograph (HPLC) equipped with a fluorescence detector were used for the identification and quantitation of PAHs. The atmospheric levels of PAHs were higher (4.66 ng/m3 yearly average) than most of the concentrations previously reported in the literature. Indian sites were found more contaminated with potently carcinogenic: four and above ringed PAHs. Based on a good correlation between the levels of lead, vanadium, BaP and BghiP, the vehicular emission appears to be a major source of the PAHs. Further, the higher levels of observed PAHs could be attributed to the vertical distribution of the aerosols, the preference of the PAHs for the particulate phase and the greater availability of the substrate in the atmosphere for their sorption. This paper also discusses the need for development of a PAHs monitoring protocol and related health effect studies in developing countries such as India. 相似文献
715.
Schaldach Rüdiger Meurer Katharina H. E. Jungkunst Hermann F. Nendel Claas Lakes Tobia Gollnow Florian Göpel Jan Boy Jens Guggenberger Georg Strey Robert Strey Simone Berger Thomas Gerold Gerhard Schönenberg Regine Böhner Jürgen Schindewolf Marcus Latynskiy Evgeny Hampf Anna Parker Phillip S. Sentelhas Paulo César 《Regional Environmental Change》2018,18(1):161-173
Regional Environmental Change - This article describes the design of a new model-based assessment framework to identify and analyse possible future trajectories of agricultural development and... 相似文献
716.
Jan Weiss Andreas Stephan Tatiana Anisimova 《Journal of Environmental Planning and Management》2019,62(2):342-363
Using recent data on a cross-section of Swedish chemical and pulp and paper firms, this paper provides novel empirical insights into the Porter hypothesis. Well-designed environmental regulation can stimulate firms’ innovative capabilities, while at the same time generating innovation offsets that may both offset net compliance costs and yield a competitive edge over those firms that are not affected by such regulations. In doing so, we also test the alleged effectiveness of regulatory time strategies in stimulating innovation activities of regulated firms. We find evidence for the effectiveness of such well-designed regulations: announced rather than existing regulation induces innovation and some innovation offsets. Our results imply that empirical tests of the Porter hypothesis that do not account for its dynamic nature, and that do not measure well-designed regulations, might provide misleading conclusions as to its validity. 相似文献
717.
Lukas Stark Michael Düring Stefan Schoenawa Jan Enno Maschke Cuong Manh Do 《Traffic injury prevention》2019,20(4):S126-S132
AbstractObjective: The Vision Zero initiative pursues the goal of eliminating all traffic fatalities and severe injuries. Today’s advanced driver assistance systems (ADAS) are an important part of the strategy toward Vision Zero. In Germany in 2018 more than 26,000 people were killed or severely injured by traffic accidents on motorways and rural roads due to road accidents. Focusing on collision avoidance, a simulative evaluation can be the key to estimating the performance of state-of-the-art ADAS and identifying resulting potentials for system improvements and future systems.This project deals with the effectiveness assessment of a combination of ADAS for longitudinal and lateral intervention based on German accident data. Considered systems are adaptive cruise control (ACC), autonomous emergency braking (AEB), and lane keeping support (LKS).Methods: As an approach for benefit estimation of ADAS, the method of prospective effectiveness assessment is applied. Using the software rateEFFECT, a closed-loop simulation is performed on accident scenario data from the German In-Depth Accident Study (GIDAS) precrash matrix (PCM). To enable projection of results, the simulative assessment is amended with detailed single case studies of all treated cases without PCM data.Results: Three categories among today’s accidents on German rural roads and motorways are reported in this study: Green, grey, and white spots.Green spots identify accidents that can be avoided by state-of-the-art ADAS ACC, AEB, and LKS. Grey spots contain scenarios that require minor system modifications, such as reducing the activation speed or increasing the steering torque. Scenarios in the white category cannot be addressed by state-of-the-art ADAS. Thus, which situations demand future systems are shown. The proportions of green, grey, and white spots are determined related to the considered data set and projected to the entire GIDAS.Conclusions: This article describes a systematic approach for assessing the effectiveness of ADAS using GIDAS PCM data to be able to project results to Germany. The closed-loop simulation run in rateEFFECT covers ACC, AEB, and LKS as well as relevant sensors for environment recognition and actuators for longitudinal and lateral vehicle control.Identification of green spots evaluates safety benefits of state-of-the-art level 0–2 functions as a baseline for further system improvements to address grey spots. Knowing which accidents could be avoided by standard ADAS helps focus the evolution of future driving functions on white spots and thus aim for Vision Zero. 相似文献
718.
Jan Nyssen Fikre Fetene Mekete Dessie Getachew Alemayehu Amare Sewnet Alemayehu Wassie Mulugeta Kibret Kristine Walraevens Ben Derudder Bart Nicolai Sofie Annys Firew Tegegne Steven Van Passel Amaury Frankl Elie Verleyen Dereje Teklemariam Enyew Adgo 《Regional Environmental Change》2018,18(7):2089-2104
We have investigated the relevance of the notion of “peripheralism” in the Beles basin. In this lowland border area of Ethiopia, important investments require an evaluation of their socio-economic and ecological impacts in the light of Ethiopia’s Climate-Resilient Green Economy (CRGE) strategy. We contrasted literature of different periods with field observations. In the middle and lower parts of the basin, the Gumuz people traditionally practised shifting cultivation. Resettlement of highlanders is particularly linked to water and land resources. A large irrigation project was initiated in the 1980s, but vegetables and fruits face post-harvest losses. Large water transfers from Lake Tana since 2010 affect the movement of people, the hydrogeomorphology, and ecology of the river. In several parts of the basin, the settlers’ economy now dominates. Many Gumuz became sedentary but maintained their agricultural system, particularly in the south of the lower basin. Land titling allowed allocation of “vacant” areas to transnational or domestic investors. As a result, the semi-natural vegetation is frequently replaced by open cropland, leading to decreased carbon storage and increased soil erosion. This and water abstraction for irrigation jeopardise hydropower production, in contradiction with the CRGE objectives. Despite the recent developments, the contrasts in economic activity make the core-periphery dichotomy to remain actual in the Beles basin. The resettlements and permanent cropping tend to make the upper basin part of the core. However, the installation of a transit road and commercial farms in the lower basin do not allow to consider that a non-peripheral integration has taken place. 相似文献
719.
Mikael Larsson Chuan Wang Jan Dahl Anita Wedholm Cajsa Samuelsson Marcel Magnusson 《International Journal of Green Energy》2013,10(2):127-137
Residue materials generated in the metallurgical industry have gained an increasing importance, both from the points of view of energy and material supply. A joint process integration model for the integrated steel plant system is developed and used in this paper. It takes into account both residue materials and energy recirculation for the system. The potential for increased recirculation and the effect on the system from an environmental point of view is presented, and implementations and practical experiences are discussed. The model developed can serve as a benchmark for different steelmaking operations and constitute a basis for the continuous work involved in material, energy, environment or economic analyses for the steel production system. 相似文献
720.
Peter Sandberg Mikael Larsson Jan Dahl Mats Söderström Henrik Vourinen 《International Journal of Green Energy》2013,10(2):159-170
It is crucial for a steel making production system to operate at the lowest possible production cost, while satisfying stability and reliability conditions. To plan future production strategies, it is therefore important to be able to model the system behaviour when internal and external parameters are changed. In this study the sensitivity and stability of an optimised solution, of an integrated steel plant, have been investigated. The solution’s sensitivity has been analysed taking both internal process changes and external price variations into account, through applying both simulation and optimisation. The analysis also includes both costs and environmental issues such as carbon dioxide and sulphur emissions. Based on the methodology suggested, it is possible to determine the stability of the system solution, including both economic and environmental performance. 相似文献