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1.
Developing a relationship between pest abundance and damage to crops is essential for the calculation of economic injury levels (EIL) leading to informed management decisions. The crop modelling framework, APSIM, was used to simulate the impact of mouse damage on yield loss on wheat where a long-term dataset on the density of mice was available (1983–2003). The model was calibrated using results from field trials where wheat plants were hand clipped to imitate mouse damage. The grazing effect of mice was estimated using the population density, daily intake per mouse and the proportion of wheat grain and plant tissue in the diet to determine yield loss. The mean yield loss caused by mice was 12.4% (±5.4S.E.; range −0.5 to 96%). There were 7/21 years when yield loss was >5%. A damage/abundance relationship was constructed and a sigmoidal curve explained 97% of variation when accounting for different trajectories of mouse densities from sowing to harvest. The majority of damage occurred around emergence of the crop when mouse densities were >100 mice ha−1. This is the first time that field data on mouse density and a crop simulation model have been combined to estimate yield loss. The model examines the efficacy of baiting and how to estimate EILs. Because the broadscale application of zinc phosphide is cheap and effective, the EIL is very low (<1% yield loss). The APSIM model is highly flexible and could be used for other vertebrate pests in a range of crops or pastures to develop density/damage relationships and to assist with management.  相似文献   
2.

Introduction

The effectiveness of ignition interlocks at reducing drunk driving has been limited by the ability of driving-while-intoxicated (DWI) offenders to avoid court orders to install the devices.

Methods

In a pilot program in New Mexico, four Santa Fe County judges imposed home confinement (via electronic monitoring bracelets) on offenders who claimed to have no car or no intention to drive. Interlock installation rates for Santa Fe County were compared with all other counties in New Mexico over a 2-year program and 2-year post-program period.

Results

During the two program years, 70% of the drivers convicted of DWI in Santa Fe County installed interlocks, compared to only 17% in the other counties, but when the program was terminated, the Santa Fe installation rate fell by 18.8 percentage points.

Summary

Mandating the alternative sanction of house arrest led to the highest reported interlock installation rate for DWI offenders.

Impact on Industry

Impaired driving is a substantial expense to employers, particularly when it bars driving that interferes with employment. Interlocks provide a method of protecting the public while permitting the offender to drive sober. This study was directed at increasing interlock use by DWI offenders.  相似文献   
3.
对大量不同行业和水样的实际样品进行BOD微生物传感器快速测定法与五日生化需氧量法(BOD5)的比对分析,在此基础上,指出了BOD快速测定法的注意事项以及应用范围.  相似文献   
4.
At the Earth Summit in Johannesburg in 2002, partnerships were touted as one of the key routes to sustainable development. But can partnerships really deliver improvements to rural livelihoods? This paper reviews one set of claimed partnerships, those between forestry companies and local individuals or communities, to assess the benefits, and the costs, to local livelihoods. Most arrangements between forestry companies and local communities are not equitable enough to be called partnerships, so the term “deal” is preferred. Positive local impacts of company–community deals include sharing of risks, better returns to land than otherwise possible, opportunities for income diversification, access to paid employment, development of new skills, upgrading of local infrastructure and environmental improvement. However, company–community deals have not yet proved sufficient to lift people out of poverty. They remain supplementary rather than central to income generation. Furthermore, while some deals have resulted in greater cohesion and organisation among community groups, there is as yet little evidence of substantial increases in community bargaining power. Ways forward to increase returns to communities (and to their counterpart companies) centre on moving towards more equal partnerships, by raising community bargaining power, fostering the roles of brokers and other third parties, and developing equitable, efficient and accountable governance frameworks.  相似文献   
5.
Immune responses constitute a major way for hosts to defend themselves against parasites. Because hosts do not habitually produce strong responses all the time, immune responses might be costly to produce or maintain. We tested experimentally if the production of a response to a challenge with a novel antigen resulted in a cost in terms of fitness using the highly colonial house martin Delichon urbica as a model system. We injected adult breeding birds during laying of the first clutch with either Newcastle disease virus (NDV) or a control injection, and the clutch was subsequently removed to induce relaying. NDV stimulates the non-specific immune system, causing production of antibodies during a period of more than 2 weeks. Accordingly, we found an increase in leukocyte counts in experimental birds compared to controls. Experimental treatment reduced the frequency of re-laying, caused a delay in timing of relaying and a reduction in brood size. Quality of nestlings in terms of body size, body mass and T-cell-mediated immune response did not differ significantly between treatments. Overall, seasonal reproductive success differed significantly between treatments, showing that the production of an immune response by adult birds is costly in terms of future fecundity.  相似文献   
6.
陕西省黄土崩塌隐患区宅基地选址方案研究   总被引:1,自引:0,他引:1  
在对黄土崩塌所造成的伤亡、损失及灾害成因的调查的基础上,结合对黄土地形地貌、颗粒结构、岩土特征和力学特性的研究分析,提出了在黄土高原区内黄土崩塌隐患区居民宅基选址应注意的问题,变被动防灾为主动预防,这对地处黄土高原区山西、陕西、甘肃等省的居民宅基选址具有重要的指导意义和参考价值。  相似文献   
7.
环境产权拍卖机制及定价研究   总被引:1,自引:0,他引:1  
在解析环境产权属性的基础上,探讨了环境产权市场交易的基础和条件,设计了一种具有可分性的环境产权拍卖机制,并研究了在这种拍卖机制下,竞标者实现自身效益最大化条件下的环境产权价格确定机制。最后讨论了这种拍卖及定价机制下政府环境管理目标的实现以及对解决环境效益外部性的作用。  相似文献   
8.
This paper argues the possibility of establishing common principles of protection from psychosocial risks (PSR) on the basis of the legal positions of the European Court of Human Rights (the Court) expressed in recent cases on degrading treatment and occupational health. The author focuses on the positive obligations of the States to ensure the protection of the right for life and of the right to respect for private life. The prohibition of degrading treatment in relations between private persons is also considered as relevant to the issue of the protection from PSR. Analyzing the Court's case law (judgments of the Court) we substantiate the possibility of claiming protection from PSR under the European Convention on Human Rights, namely, articles 2, 3 and 6, 8.  相似文献   
9.
Indraprastha Power Station (IPP Stn) and Rajghat Power House (RPH), owned by Delhi Electric Supply Undertaking, are both coal-fired power stations located on Ring Road in New Delhi. Ash content of the coal used ranges between 38–47%. The ash is collected in electrostatic precipitators which have an efficiency of 99.3% (IPP station), and 99.7% (RPH). There are instances of major dust pollution around the power stations from fly ash dispersal. The main method of disposal of fly ash from the power stations is by mixing with water, the resultant slurry is pumped through pipes to ash disposal ponds. The supernatant from these ponds is discharged into River Yamuna. Field studies have revealed large quantities of fly ash being deposited into the river. Local populations of Eichhornia crassipes have reduced dramatically between 1987–1995, with a marked reduction in the year 1994–1995. Field studies, conducted in January, 1995 have investigated the impact of fly ash dispersal in the Delhi region with particular reference to metal contamination. Elemental concentrations for a range of elements are determined by ICP-AES in fly ash and top soils along four transects from the power stations up to a distance of 8 km. The effects of fly ash leachates from the ash settling ponds on the river are determined by analyzing river overbank soils and vegetation for their elemental contents. It is concluded that fly ash dispersal from the stacks are a source of alkali, alkaline-earth and to some extent heavy metals in soils in the vicinity of the power stations, and enrichment of elements in river overbank soils are a result of discharge of fly ash leachates from ash disposal ponds. However, the impact from both these sources of metal contamination is not large enough to give cause for concern. Marked reduction in populations of Eichhornia crassipes downstream of the river where it receives leachates from the ash disposal ponds are attributed to turbidity of the ash pond leachates and metal toxicity. Elemental enrichment in the floodplain soils, as a result of fly ash particle deposition during monsoons, may enhance the horticultural value of these soils as is shown by a healthy cultivated crop of Brassica juncea.  相似文献   
10.
Although Beijing has carried out municipal solid waste (MSW) source separation since 1996, it has largely been ineffective. In 2012, a “Green House” program was established as a new attempt for central sorting. In this study, the authors used material flow analysis (MFA) and cost benefit analysis (CBA) methods to investigate Green House’s environment and economic feasibility. Results showed that the program did have significant environmental benefits on waste reduction, which reduced the amount of waste by 34%. If the Green House program is implemented in a residential community with wet waste ratio of 66%, the proportion of waste reduction can reach 37%. However, the Green House is now running with a monthly loss of 1982 CNY. This is mainly because most of its benefits come from waste reduction (i.e., 5878 CNY per month), which does not turn a monetary benefit, but is instead distributed to the whole of society as positive environmental externalities. Lack of government involvement, small program scale, and technical/managerial deficiency are three main barriers of the Green House. We, thus, make three recommendations: involve government authority and financial support, expand the program scale to separate 91.4 tons of waste every month, and use more professional equipment/technologies. If the Green House program can successfully adopt these suggestions, 33.8 tons of waste can be reduced monthly, and it would be able to flip the loss into a profit worth 35034 CNY.
  相似文献   
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