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Following disasters, governments often clamor to quickly reduce risk, rebuild communities and restore permanence. The pressure to urgently address complex, difficult decisions can result in reactive policies that may increase long-term vulnerability of affected populations. Sri Lanka in the aftermath of the 26 December 2004 tsunami represents such an example: a hastily designed coastal buffer zone policy has incited massive relocation of affected populations and resulted in social, economic and environmental problems that threaten the well-being of poor coastal communities. We review the impacts of this policy from its inception, days after the tsunami hit the island, until its revision, approximately 10 months following the disaster. We then apply a framework to conceptualize the components of vulnerability within Sri Lanka's coastal, human–environment system and to identify where post-disaster policies should focus to reduce vulnerability of coastal populations more effectively. From this analysis, it is apparent that the buffer zone policy gave disproportionate attention to reducing exposure to future tsunamis and, subsequently, did not address the critical social, economic and institutional factors that influenced sensitivity to the hazard. Post-disaster policies aimed at sustainable re-development should be informed by an analysis of the components of vulnerability that comprise a system and how these can be most effectively influenced during the separate short-term and long-term phases of rebuilding.  相似文献   

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Prenatal diagnosis on chorionic villous tissue was performed for a woman with the karyotype 46,XX,t(2;18)(q32;q12)—a subtle ‘difficult’ translocation. The case illustrates the necessity of good quality cytogenetics for accurate prenatal diagnosis. For chorionic villi this can be obtained only with long-term culture.  相似文献   

4.
 The phonotactic capacity of tachinid flies to acoustically detect and localize a sound source simulating their cricket host was investigated in a large flight room. Acoustic measurements were performed to estimate the actual stimulus delivered to the flies, revealing highly heterogeneous sound fields. When presented with a simulated cricket song in red or infrared light conditions, the flies readily flew to the sound source and landed on it. Behavioural phonotactic thresholds were established as a function of carrier frequency and were found to coincide well with the frequency of the host's natural song (4.5–5.2 kHz). Experiments revealed that the same range of frequencies is preferentially attractive to the free-flying flies, and that the reliability of signal detection in the presence of noise is best at behaviourally relevant frequencies. Received: 23 February 2000 / Accepted in revised form: 6 June 2000  相似文献   

5.
Global challenges have exacerbated a search for solutions to poverty and environmental degradation. Integration it was argued would help address the twin challenge. Integrated Water Resources Management (IWRM) was supposed to be that magic bullet and was embraced by scientists because of the clinical efficiency with which it argued for integrated analysis of sectors and resources and of systems and scale conditions. This paper argues that effective implementation of the Water-Energy-Food (WEF) Nexus can be supported by robust science. The corollary that robust science automatically leads to effective implementation is not always known to be true. The nexus approach sheds light on the challenges of implementation by introducing concepts of trade-offs and thresholds and consequently emphasizes the importance of transdisciplinary approaches to sustainable development. This paper reviews the results of recent research to offer tentative answers to the following questions: (a) Why is the governance dimension important to undertake an integrated analysis of water-energy-food challenges? (b) What does the nexus approach connote in normative and institutional terms? (c) What does implementation mean in nexus terms? (d) How can we establish if the nexus approach is an improvement over business as usual? and (e) What tools are available that would enable translation of results of scientific research to create an evidence base that would enable decision makers to act in support of sustainable development?  相似文献   

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The feasibility of copper recovery by induced crystallization in a long period(174 days) was investigated in a seeded fluidized bed reactor(FBR). The process was divided into 3 periods according to different influent conditions, and the period III was separated into III-a and IIIb due to the adjustment of the molar ratio of CO_3~(2-)concentration to copper concentration([CT]/[Cu~(2+)]). The removal efficiency could exceed 95% and the average effluent copper concentration decreased to 3.0 mg/L. The mean particle size of seed grains with copper crystals coating on, raised to 0.36 mm from initial 0.18 mm. During period III-a, the supersaturation exceeded 2.88 × 104, the removal efficiency decreased to 60%–80% and the particle size dropped to 0.30 mm, due to the generation of fines by homogeneous crystallization and seeds breaking. And the morphology of the crystals on the seed grains changed from rod-like to spherical which lead to the particle size decreasing. In period III-b,the supersaturation was modified by adjusting the molar ratio of [CT]/[Cu2+] to 1.2 from 2.The efficiency was back to 95% and the mean particle size grew to 0.36 mm at the end of IIIb, the crystals coating on the seeds turned back to rod-like products of good stability. This study illustrated that the copper salt crystal could keep on growing on the seed grains for over 150 days, the feasibility and controllability of copper recovery by induced crystallization process in FBR were satisfactory, even under the dramatic changes in influent conditions.  相似文献   

7.
The responses of soil ammonia-oxidizing archaea(AOA) and ammonia-oxidizing bacteria(AOB) to mercury(Hg) stress were investigated through a short-term incubation experiment.Treated with four different concentrations of Hg(CK,Hg25,Hg50,and Hg100,denoting 0,25,50,and 100 mg Hg/kg dry soil,respectively),samples were harvested after 3,7,and 28 day incubation.Results showed that the soil potential nitrification rate(PNR) was significantly inhibited by Hg stress during the incubation.However,lower abundances of AOA(the highest in CK: 9.20 × 10~7 copies/g dry soil; the lowest in Hg50: 2.68 × 10~7 copies/g dry soil) and AOB(the highest in CK: 2.68 × 10~7 copies/g dry soil; the lowest in Hg50:7.49 × 10~6 copies/g dry soil) were observed only at day 28 of incubation(P 0.05).Moreover,only the community structure of soil AOB obviously shifted under Hg stress as seen through DGGE profiles,which revealed that 2–3 distinct AOB bands emerged in the Hg treatments at day 28.In summary,soil PNR might be a very useful parameter to assess acute Hg stress on soil ecosystems,and the community structure of soil AOB might be a realistic biological indicator for the assessment of heavy metal stress on soil ecosystems in the future.  相似文献   

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杨伟利 《环境》2007,(6):66-66
2007年4月,清远市政府就清远市整治违法排污企业保障群众健康环保专项行动和节能减排两项工作专门作了部署,要求各地扎实推进环保专项行动,落实节能减排措施,确保环保专项行动和节能减排工作取得实效.  相似文献   

9.
Global demand for bio-fuels continues unabated. Rising concerns over environmental pollution and global warming have encouraged the movement to alternate fuels, the world ethanol market is projected to reach 86 billion litres this year. Bioethanol is currently produced from land-based crops such as corn and sugar cane. A continued use of these crops drives the food versus fuel debate. An alternate feed-stock which is abundant and carbohydrate-rich is necessary. The production of such a crop should be sustainable, and, reduce competition with production of food, feed, and industrial crops, and not be dependent on agricultural inputs (pesticides, fertilizer, farmable land, water). Marine biomass could meet these challenges, being an abundant and carbon neutral renewable resource with potential to reduce green house gas (GHG) emissions and the man-made impact on climate change. Here we examine the current cultivation technologies for marine biomass and the environmental and economic aspects of using brown seaweeds for bio-ethanol production.  相似文献   

10.
Brundtland GH 《环境》1994,36(10):16-20
Norway's Prime Minister Gro Harlem Brundtland holds a medical degree from the University of Oslo and a Master's degree in Public Health from Harvard University. She served as Norway's Minister of the Environment during 1974-79, and was elected to the Norwegian parliament in 1977. Brundtland is currently chairperson of the World Commission on Environment and Development with ten years of experience as a physician and twenty years as a politician. An edited version of her keynote address to the 1994 International Conference on Population and Development is presented. The Minister's experience has taught her that improved life conditions, a greater range of choices, access to unbiased information, and true international solidarity are the signs of human progress. She stresses the need to empower people, educate them, care for their health, and provide them with equal opportunity to achieve economically. Available combined resources need to be used more efficiently through a reformed and better coordinated UN system, policies must be changed, the role and status of women strengthened, safe, comprehensive reproductive health services provided, and measures taken to achieve a balance between population size and sustainable development in keeping with available global resources.  相似文献   

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水十条 水实条——对《水污染防治行动计划》的解读   总被引:2,自引:0,他引:2  
《水污染防治行动计划》(以下称《水十条》)是当前和今后一个时期全国水污染防治工作的行动指南,标志着我国水环境保护工作进入崭新的阶段。《水十条》全文每条每款均贯穿一个"实"字,充分体现了求真务实的作风,给民群众以信心。  相似文献   

14.
Ammonia(NH_3) volatilization is a major pathway of nitrogen(N) loss from soil-crop systems.As vegetable cultivation is one of the most important agricultural land uses worldwide,a deeper understanding of NH_3 volatilization is necessary in vegetable production systems.We therefore conducted a 3-year(2010–2012) field experiment to characterize NH_3 volatilization and evaluate the effect of different N fertilizer treatments on this process during the growth period of Chinese cabbage.Ammonia volatilization rate,rainfall,soil water content,p H,and soil NH_4~+were measured during the growth period.The results showed that NH_3 volatilization was significantly and positively correlated to topsoil p H and NH4+concentration.Climate factors and fertilization method also significantly affected NH_3 volatilization.Specifically,organic fertilizer(OF) increased NH_3 volatilization by 11.77%–18.46%,compared to conventional fertilizer(CF,urea),while organic–inorganic compound fertilizer(OIF) reduced NH_3 volatilization by 8.82%–12.67% compared to CF.Furthermore,slow-release fertilizers had significantly positive effects on controlling NH_3 volatilization,with a 60.73%–68.80% reduction for sulfur-coated urea(SCU),a 71.85%–78.97% reduction for biological Carbon Power~#174; urea(BCU),and a 77.66%–83.12% reduction for bulk-blend controlled-release fertilizer(BBCRF)relative to CF.This study provides much needed baseline information,which will help in fertilizer choice and management practices to reduce NH_3 volatilization and encourage the development of new strategies for vegetable planting.  相似文献   

15.
The responses of activities, abundances and community structures of soil denitrifiers to mercury (Hg) stress were investigated through a short-term incubation experiment. Four soil treatments with different concentrations of Hg (CK, Hg25, Hg50, and Hg100, denoted as 0, 25, 50, and 100 mg Hg/kg dry soil, respectively) were incubated for 28 days. Soil denitrification enzyme activity (DEA) was measured at day 3, 7 and 28. The abundances and community structures of two denitrification concerning genes, nirS (cd1-nitrite reductase gene) and nosZ (nitrous oxide reductase gene), were analyzed using real-time PCR and denaturing gradient gel electrophoresis (DGGE). Results showed that soil DEA was significantly stimulated in the treatments of Hg25 and Hg50 compared with others at day 7. Meanwhile, no difference in the abundances of soil nirS and nosZ was found between Hg spiked treatments and CK, except the lower abundance of nirS (P<0.05) in the Hg added treatments compared with that in the CK at day 28. The community structures of denitrifiers based on nirS gene presented obvious change at day 7 along with the Hg additions, however, no variation was found in all treatments based on the nosZ gene. The results indicated that Hg (Hg25 and Hg50) had a strongly short-term stimulation on soil DEA, and nirS gene is more sensitive than nosZ gene to Hg stress.  相似文献   

16.
Most prior climate change assessments for U.S. agriculture have focused on major world food crops such as wheat and maize. While useful from a national and global perspective, these results are not particularly relevant to the Northeastern U.S. agriculture economy, which is dominated by dairy milk production, and high-value horticultural crops such as apples (Malus domestica), grapes (Vitis vinifera), sweet corn (Zea mays var. rugosa), cabbage (Brassica oleracea var. capitata), and maple syrup (sugar maple, Acer saccharum). We used statistically downscaled climate projections generated by the HadCM3 atmosphere–ocean general circulation model, run with Intergovernmental Panel on Climate Change future emissions scenarios A1fi (higher) and B1 (lower), to evaluate several climate thresholds of direct relevance to agriculture in the region. A longer (frost-free) growing season could create new opportunities for farmers with enough capital to take risks on new crops (assuming a market for new crops can be developed). However, our results indicate that many crops will have yield losses associated with increased frequency of high temperature stress, inadequate winter chill period for optimum fruiting in spring, increased pressure from marginally over-wintering and/or invasive weeds, insects, or disease, or other factors. Weeds are likely to benefit more than cash crops from increasing atmospheric carbon dioxide. Projections of thermal heat index values for dairy cows indicate a substantial potential negative impact on milk production. At the higher compared to lower emissions scenario, negative climate change effects will occur sooner, and impact a larger geographic area within the region. Farmer adaptations to climate change will not be cost- or risk-free, and the impact on individual farm families and rural communities will depend on commodity produced, available capital, and timely, accurate climate projections.  相似文献   

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20世纪90年代末,日本政府面对21世纪的环境和资源压力.针对严峻的资源与环境问题,提出了建立循环经济的构想,2000年还把建立循环型社会提升为基本国策,将该年定为“循环型社会元年”,并颁布和实施了《循环型社会形成推动基本法》等6部法律,采职了一系列行动措施,标志着日本进入了推进循环经济,建立循环型社会的全面发展阶段。日本在推进建设循环型社会进程中,理念先进,措施具体,效果明显。其中.完备的立法和严格的执法是根本保障;必要的经济支持和鼓励优惠政策是重要条件;建立生态工业园区,发展静脉产业是典型示范;以政府绿色采购来启动和引导市场需求是有效手段;政府相关部门管理职能强化和职责明晰是组织保证;加强科学研究,发挥公众和中介组织作用是重要措施。  相似文献   

18.
在人类历史上 ,由于缺乏必要知识 ,将城市建在不适当位置并被地质灾害毁灭的事时有发生 ,楼兰古城就是因地质灾害而消亡的楼兰古城建在古孔雀河下游河道上 ,孔雀河水是该城的唯一水源。公元 4~ 7世纪间 ,古城上游河段曾先后两次发生河岸滑坡堵塞河水 ,形成堰塞湖 ,导致孔雀河改道 ,从而彻底断绝了维系楼兰古城生命的唯一水源 ,古城不得不被废弃而且无法复兴我国是地质灾害频繁的国家之一 ,加之现代化进程中的负面影响 ,必须重视和加强城市环境地质研究  相似文献   

19.
Leather processing employs copious amounts of water. This leads to the generation of enormous amounts of liquid effluent. The high effluent volume requires huge investments for effluent treatment plants in order to meet the required specification for the discharge of liquid effluents to various water bodies. Increasingly therefore, water use minimization in leather processing assumes greater significance due to increased treatment costs. End-of-pipe treatment methods alone do not meet the requirements and hence, in-plant control measures are gaining importance. The new era of cleaner technology has begun in leather processing. Pre-tanning and tanning operations contribute about 57% of the water consumption in leather processing and the washings about 35%. The proper adoption of integrated cleaner technologies provides a viable solution to the conservation of water in leather processing. This paper presents an integrated approach for water use minimization through recycling and optimization in leather processing. The integrated approach provides considerable reduction in the use of process water.  相似文献   

20.
The soil quality concept provides a tool to help quantify the combined biological, chemical and physical response of soil to crop management practices. Our objective was to quantify effects of 10 fertilizer and farm yard manure (FYM) treatments applied for 31 years to a rotation that included maize (Zea mays), pearl millet (Pennisetum americanum), wheat (Triticum aestivum) and cowpea (Vigna unguiculata) on an Inceptisol at the Indian Agricultural Research Institute in New Delhi, India. A soil quality index (SQI) based on six soil functions (i.e. the soil's ability to: accommodate water entry, facilitate water movement and storage, resist surface degradation, resist biochemical degradation, supply plant nutrients and sustain crop productivity) was derived for each treatment using bulk density, water retention, pH, electrical conductivity (EC), plant-available nutrients, soil organic matter (SOM), microbial biomass, soil enzymes and crop yield. SQI ratings ranged from 0.552 (unfertilized control) to 0.838 for the combined NPK fertilizer plus manure treatment. Comparisons among treatments indicated that SQI increases associated with the combined (NPK + manure) treatment were distributed as follows: N (7.1% increase), P (7.8%), K (14.4%), Zn (4.8%) and manure (15%). The control (−11.4%) and N alone (−5.1%) resulted in degradation compared to a reference soil (no fertilizer/manure, no crop), and NP alone or sub-optimal rates of NPK were on the verge of degradation. Hand weeding and sulphur application had no measurable effect on SQI. High K fixing capacity was a limiting factor for these soils, even when FYM was applied. The lower SQI rating associated with N or NP-only treatments suggests that two of the most common fertilizer management practices in India may not be sustainable. The SQI was calculated without the weighting factors too, which revealed that the weighting factors did not affect the relative ranks of individual treatments.  相似文献   

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