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1.
本文应用“专家估计”模型预测了上海市废弃电器电子产品的产生量,分析了家电“以旧换新”政策实施下废弃电器电子产品的回收处理特点以及上海市拆解处理能力现状,发现上海市目前的拆解处理能力无法满足2015年废弃电器电子产品回收处理量的需求,提出相应的解决对策。  相似文献   

2.
Livestock production systems will inevitably be affected as a result of changes in climate and climate variability, with impacts on peoples’ livelihoods. At the same time, livestock food chains are major contributors to greenhouse gas emissions. Agriculture and livestock in particular will need to play a greater role than they have hitherto in reducing emissions in the future. Adaptation and mitigation may require significant changes in production technology and farming systems, which could affect productivity. Given what is currently known about the likely impacts on livestock systems, however, the costs of mitigating and adapting to climate change in the aggregate may not represent an enormous constraint to the growth of the global livestock sector, in its bid to meet increasing demand for livestock products. Different livestock systems have different capacities to adapt or to take on board the policy and regulatory changes that may be required in the future. Vulnerability of households dependent on livestock, particularly in the drier areas of developing countries, is likely to increase substantially, with concomitant impacts on poverty and inequity. The capacity of these systems to adapt and to yield up their carbon sequestration potential deserves considerable further study. Comprehensive frameworks need to be developed to assess impacts and trade-offs, in order to identify and target adaptation and mitigation options that are appropriate for specific contexts, and that can contribute to environmental sustainability as well as to poverty alleviation and economic development.  相似文献   

3.
Nitrate and pesticide contamination of surface and groundwater has become a major problem in intensive farming regions in Europe, with nitrate concentrations reaching values above the standard defined in 2000 by the European Water Framework Directive. In the Seine basin, a major issue is the closure and abandonment of drinking-water wells, which force water managers and drinking-water producers to explore solutions for water resource protection. Organic farming has appeared as a credible alternative to conventional farming, and this study explores the potential of organic farming to reconcile agricultural production and water quality. On the basis of agricultural statistics, survey questionnaires and experimental data, the nitrogen soil surface balance (N-SSB) has been established at the scale of a small 104-km2 catchment (The Orgeval sub-basin), representative of the intensive cash crop farming in the Seine basin. The N-surplus for arable land in specialized organic cash crop systems has been found to be half that of current conventional systems (15 kg N ha−1 yr−1 versus 30 kg N ha−1 yr−1, respectively). The N-yield in organic systems is 21% lower than in conventional systems, but total fertilization (mostly symbiotic N fixation) is also 26% lower. Whereas 2–3 years of forage legume (e.g., alfalfa) as a starter crop of the typical 7- to 10-year diversified rotation builds up N soil fertility and helps prevent weeds without pesticides, the existence of an outlet for this fodder production is a limiting factor for the economic sustainability and the environmental benefits of these farming systems. Therefore, we explored the possibility of a reconnection of livestock and crop farming systems in the Orgeval catchment, a traditional dairy farming and Brie cheese production region. We calculated the N-SSB for this type of a reconnected livestock and cropping system and found a value very close to the specialized organic cash crop system with full utilization of fodder production, leading to profitable animal production, essentially as milk in this farm design. This reconnected system is compared with the estimated situation in 1955 before separation of plant and livestock production. Furthermore, the N-SSB values were converted into infiltrating sub-root concentrations and used as a boundary condition to a biogeochemical model. Organic cropping and organic reconnected livestock cropping systems result in a 50% reduction of surface water nitrate concentrations, a surface water quality 20% better than that reconstructed for 1955, with an overall higher protein production.  相似文献   

4.
Analyses of the vulnerability of farm populations and food systems to exogenous change, whether in relation to climatic extremes, market shocks, epidemics or other concerns, have typically been approached through a focus on the place of food production or the specific sub-sector exposed to stress. Relatively little attention has been paid to the ways in which national institutions, history and social expectations transform the same signals of global change into very different outcomes in distinct geographic contexts. The channels that convey signals of change from the global to the local may also work in reverse, connecting the responses and choices of households in one geographic context to outcomes and choices of other households in quite distant places. We draw from recent case studies of farm-level vulnerability and livelihood security in Mexico and Vietnam to demonstrate that coffee smallholders’ independent responses to the risks and opportunities associated with global scale economic and environmental change, are teleconnected and thus can create feedbacks which in turn affect the present and future vulnerabilities of other smallholders around the globe.  相似文献   

5.
A Life Cycle Assessment (LCA) was performed to analyze environmental consequences of different pear production chains in terms of fossil energy use and greenhouse gas (GHG) emission in China. The assessment identified hotspots that contributed significantly to the environmental impacts of pear production from the cradle to the point of sale. The results showed that GHG emissions and fossil energy use varied in the different production chains because the environmental performance does not associate with the farming systems (i.e. organic vs. conventional), but is co-determined by farm topography and thus machinery use, by market demands to seasonality of products and thus the need for storage, and by local farming practices including manure management. The LCA could be used as a tool to guide selections of agricultural inputs with the aim of reducing environmental impacts. The results of the LCA analysis indicate that a list of choices are available to reduce energy use and GHG emission in the pear production chain, namely substitution of the traditional storage systems by an efficiently controlled atmosphere storage system, using manure for biogas production, conversion from the conventional farming to organic farming, and reduction of mechanical cultivation.  相似文献   

6.
日益增强的乳品行业竞争使乳品企业不断加强环境管理和实行清洁生产成为必然.文章阐述了在乳品行业没有国家清洁生产标准的情况下如何以ISO14001环境管理体系标准为基础开展清洁生产工作,同时提出了乳品企业开展清洁生产的方向,对乳品企业开展清洁生产工作具有一定的指导意义.  相似文献   

7.
The European livestock sector has changed rapidly in the recent past and further changes are expected in the near future due to reforms in the European Common Agricultural Policy (CAP), increasing environmental concerns and changing consumer awareness. We developed a multi-scale modeling approach for exploring spatial and temporal dynamics of livestock distribution by accounting for drivers at different spatial scales. Such approach can provide a basis for environmental impact assessments of livestock farming at broad spatial scales. Assessment of change in both quantity and location was made for six livestock types. Four contrasting scenarios were applied ranging from globalization to regionalization, as well as from low regulation levels and dominance of market forces towards a higher degree of governmental regulation. National level livestock numbers as calculated by a macro-economic model were spatially distributed at the landscape scale according to the scenario assumptions considering biophysical, socio-economic, and political forces. Results indicate for most of the old European Union (EU) member countries a decrease in livestock numbers. In the new EU member countries sheep, goats and pigs are expected to decline while beef cattle and poultry are expected to grow. Livestock densities are expected to increase both within and outside current livestock hotspot regions in absence of environmental legislations. Environmental pressure as result of high livestock densities may, however, also remain in regulated scenarios where environmental policies are implemented and income support remains stable over time due to path dependencies in the livestock sector. But contrary to the non-regulated scenario it is less likely that new areas with high risk of negative environmental impacts due to livestock farming will develop.  相似文献   

8.
针对近年来我国规模化养殖场迅速发展所带来的严重环境污染,特别是畜禽养殖废水中氨氮污染物所产生的污染,文章采用硝化反应器对其进行处理。首先进行了硝化细菌的培养驯化,然后通过连续运行试验和间歇运行试验,考察氨氮的去除效果和操作参数的影响。试验结果表明:当温度为25℃,pH为6.0~8.0,DO为4.0~6.0 mg/L,HRT为12 h,进水氨氮为200 mg/L时,出水氨氮浓度可以降低到1.0 mg/L左右,氨氮的去除率达到接近100%。  相似文献   

9.
农村环境问题,主要源于老百姓的日常生活和农业生产中农用化学物资的使用,畜禽养殖业和乡镇企业的污染以及资源的不合理开发利用而带来的生态破坏。为此,应该从环保宣传入手,提高农民的环保意识,尤其是提高农村中小学生的环保意识,进而带动家长影响社会,倡导科学使用农用化学物资,实施规模化养殖,鼓励农村废物综合利用,实行资源无害化处理,强化乡镇企业的环境监管,注重发展生态农业,从而在提高农民生活水平中,实现生态保护与农村经济发展双赢。  相似文献   

10.
我国畜禽污染现状与治理政策的有效性分析   总被引:11,自引:0,他引:11       下载免费PDF全文
针对我国农村畜禽养殖散户和专业户的畜禽粪便处理方式进行实地调查,分析了我国畜禽粪便污染现状及变化趋势,并运用计量经济模型估计了不同治理政策对减少畜禽粪便废弃的有效性.结果表明:随着我国畜禽养殖模式的转变和劳动力成本的提高,畜禽粪便污染呈现明显增长趋势,污染治理的压力进一步增加;散户和专业户的畜禽粪便处理方式存在较大差异.模型估计结果表明:制定垃圾管理规章制度、专人监管垃圾投放、建立沼气池等措施能有效减少散户的畜禽粪便污染,但对于专业户只有专人监督垃圾投放才能发挥作用.随着我国农村畜禽养殖从散养向专业户养殖方式转变,建议政府部门重点加强对养殖专业户畜禽粪便污染的管理,通过出台更严格的环境监管措施和补贴等激励机制减少其畜禽粪便环境污染.  相似文献   

11.
In consideration of the need to maintain planting-breeding balance, this article examines the capacity of the soil in Putian City, Fujian Province to absorb livestock and poultry excreta, and computes the environmental carrying capacity for livestock and poultry farming (ECCLPF) in each district of the city in terms of the fertility characteristics of the soil in the city, as well as its mix of crops cultivated and farming methods. On the basis of the computations, this work proceeds to classify the alarm grades of the city’s environmental carrying capacity for livestock and poultry framing, and assess the environmental impact of the livestock and poultry farming industry. The results of our study indicate that, the city’s ECCLPF ranges from 8.27 to 23.23 heads per ha when computed on the basis of nitrogen, and from 5.79 to 24.53 heads per ha when computed on the basis of phosphorus. A comparison between our research findings and the existing farming scale in Putian reveals that, in certain parts of the city, ECCLPF is overburdened to varying degrees. Specifically, Chengxiang District is severely overburdened, Hanjiang District and Meizhou Island have a level of overburdening between virtual overburdening and significant overburdening, Licheng District is virtually overburdened, and Xiuyu, Xianyou, and Bei’an Districts have not exceeded their environmental carrying capacity and therefore have varying levels of potential for growth.  相似文献   

12.
中国畜禽养殖业正由传统方式向规模化养殖不断推进,在经济的快速发展的同时产生了大量的环境问题。本文从畜禽养殖业环境污染现状和原因出发,从环境压力、政策导向、企业需求三个方面分析了畜禽养殖业实施清洁生产的必要性,提出了发展畜禽养殖业清洁生产应鼓励使用环保生态饲料,着重实施粪便资源化、无害化,加强法律法规体系和技术规范完善与监管。在此基础上,尝试建立新型农牧结合的互利机制,促进畜禽养殖业的清洁生产推进,进而实现地区农业可持续发展。  相似文献   

13.
畜禽养殖业的快速发展和养殖污染治理滞后的矛盾已经成为我国畜禽养殖业发展的瓶颈。对辽西畜禽养殖专业村饮用水、空气指标进行了检测。结果表明,辽西地区畜禽养殖业的快速发展对大气、水体和土壤环境造成了严重污染,需要采取有效治理措施,消除畜禽养殖污染对经济发展的制约。  相似文献   

14.
农户生计与耕地利用之间的关系已经成为理解人地关系的重要切入点。论文以宁夏盐池县为例,在可持续生计框架下,从农户生计资本和生产要素配置两个角度,探讨农户生计分化及其对耕地利用的影响。结果表明:1)盐池县兼业户与非农就业户合计占调查农户的58%,农户非农化现象普遍;2)劳动力越多、人均耕地越少的农户,其家庭非农收入占比越高,生计资本是农户生计分化的“推力”;3)务农机会成本越高的农户其生计分化程度越高,务农机会成本是农户生计分化的“拉力”;4)随着生计分化程度的增加,耕地利用的生产要素投入强度呈递减态势,但是兼业户的耕地利用效率高于纯农户和非农就业户。农牧交错区同时面临着生态保护、农牧业生产、脱贫攻坚等挑战,政策制定需充分考虑当地农户的生计特征与人地关系的演变规律,加强非农就业引导,鼓励农户土地流转,促进农户生计多样化,实现生态、经济、社会效益“共赢”发展。  相似文献   

15.
This special issue of Agriculture, Ecosystems and Environment recognizes the important contribution of Dr. J.W. Sturrock to agroecosystem and environmental research through his long-term role as Editor-in-Chief (1982–2000). An historical overview of agroecosystem and environmental research is provided to illustrate the continued growth of scientific endeavor in this area, and to show its importance for a better understanding of ecological interactions within agroecosystems and especially at the agroecosystem/environmental interface. The papers collected in this special issue are selected to illustrate the breadth and diversity of agroecosystem and environmental research. They can be placed in the following four areas: the environmental impact of farming systems; the management of organic resources, the link between the ecology of farming systems and the environment; and the ecological interactions that occur within or between agricultural systems. Intensification of food production, population growth, technological change, changing land-use patterns, and global change will further impact the structure and functional properties of agroecosystems, and intensify the interaction between agriculture and the environment, and will present a major continuing need for research in the 21st century.  相似文献   

16.
青藏高原的放牧系统具有重要的生态和生计意义,但目前正受到气候变化和人为干扰的双重威胁。为寻找改善现状的着力点,有必要探究青藏高原放牧系统的现状与演变趋势。以青藏高原东北部的共和县为例,基于历史统计数据、地方志与文献资料,在社会—生态系统的视角下,运用描述系统演变的扰沌模型,分析共和县放牧社会—生态系统的历史变迁、现状以及未来发展趋势。其中与经济相关的家庭生计—市场子系统目前处于平稳积累资源阶段,与生态相关的草—畜子系统处于释放阶段的早期,社会子系统处于偏离正常轨迹的重组阶段。草—畜子系统的情况恶化并将为更大时空尺度的社会子系统带来负面影响。未来要注意防止家庭畜牧生产与畜牧业市场的过度连接,维护畜牧产业链上的获益公平,提升牧民收入来源多样化程度;注重草地治理,提升基层监理队伍的数量和质量,鼓励合作社优化畜群结构从而与草地匹配,制定合理的政策帮助牧民社会适应外来变化。  相似文献   

17.
南海区畜禽养殖污染现状及防治对策   总被引:3,自引:1,他引:3  
研究了南海区畜禽养殖污染现状,结果表明畜禽养殖污染已成为一个重要的污染源,其排放进入水体的COD、NH3-N量已超过工业污水的排放量,但小于城镇生活污水的排放量;南海区畜禽粪便土地负荷警报值为1.06,呈现出较严重的环境压力水平。同时提出了畜禽养殖业污染的防治对策,以促进畜禽养殖业环境与经济的协调发展。  相似文献   

18.
The water–energy–food nexus is being promoted as a conceptual tool for achieving sustainable development. Frameworks for implementing nexus thinking, however, have failed to explicitly or adequately incorporate sustainable livelihoods perspectives. This is counterintuitive given that livelihoods are key to achieving sustainable development. In this paper we present a critical review of nexus approaches and identify potential linkages with sustainable livelihoods theory and practice, to deepen our understanding of the interrelated dynamics between human populations and the natural environment. Building upon this review, we explore the concept of ‘environmental livelihood security’ – which encompasses a balance between natural resource supply and human demand on the environment to promote sustainability – and develop an integrated nexus-livelihoods framework for examining the environmental livelihood security of a system. The outcome is an integrated framework with the capacity to measure and monitor environmental livelihood security of whole systems by accounting for the water, energy and food requisites for livelihoods at multiple spatial scales and institutional levels. We anticipate this holistic approach will not only provide a significant contribution to achieving national and regional sustainable development targets, but will also be effective for promoting equity amongst individuals and communities in local and global development agendas.  相似文献   

19.
The environmental impact of meat is high mainly due to the feed required by livestock in combination with the impacts of cultivating, transporting and processing of feed crops such as tapioca and grains. Like regular feed crops, livestock also feed on residue from the food industry, such as pulp, scrap and peels. Both types of raw material have different environmental impacts. Feeding food residue to livestock is an efficient way to upgrade a low quality material into high quality foods. In the Netherlands, food residue represents the majority of the feedstock for feed. Distinguishing crops from food residue has consequences for the ascribed environmental impact of meat. This paper separates these two streams using volume, environmental impact and their relevance in meat production. An assessment is made of three food industries (sugar beet industry, vegetable oil industry and potato product industry) that produce the largest stream of food residue, and of the pork industry, as an example of meat production. The environmental impact of food residue-based feed is allocated in three different ways: mass ratio, economic basis, and no assigned burden. We found that the amount of pork produced from food residue is substantial. The environmental impact of food residue-based feed is also significantly lower than grain-based feed. We discuss changes in vegetable and in animal product consumption that influence the environmental impact of pork. It is concluded that the use of current food residue keeps the environmental impact of livestock foods relatively low. However, a further increase in meat consumption would require more feed grains with a correspondingly larger environmental impact because food residues are used up.  相似文献   

20.
规模化畜禽养殖小区采用生态工程处理养殖废水和粪便,是一种新出现的环保型养殖模式,与传统的分散养殖方式相比,具有集约型、减量化的特点.本文通过实地调查,监测某规模化畜禽养殖小区及其替代同等规模分散养殖户的主要污染物排放浓度和排放总量,为核算污染物初始排放量、削减量及外排量提供基础数据,以研究和核定实施集约化养殖后污染物减排成效.结果表明,规模化畜禽养殖替代散户养殖,能大幅度减少规模养殖区域养殖废水及污染物外排量,减少幅度为:废水量41.6%,COD 93.5%,NH3-N 99.9%,TP 99.4%,SS 90.5%.养殖小区通过源头减排,提高末端治理效率,并配套农牧结合的有效实施,可使替代养殖户的排污量削减全额认定,实现污染物“零排放”.  相似文献   

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