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21.
Martin Drechsler Henrik G. Smith Astrid Sturm Frank Wätzold 《Conservation biology》2016,30(4):894-899
Payments to compensate landowners for carrying out costly land‐use measures that benefit endangered biodiversity have become an important policy instrument. When designing such payments, it is important to take into account that spatially connected habitats are more valuable for many species than isolated ones. One way to incentivize provision of connected habitats is to offer landowners an agglomeration bonus, that is, a bonus on top of payments they are receiving to conserve land if the land is spatially connected. Researchers have compared the cost‐effectiveness of the agglomeration bonus with 2 alternatives: an all‐or‐nothing, agglomeration payment, where landowners receive a payment only if the conserved land parcels have a certain level of spatial connectivity, and a spatially homogeneous payment, where landowners receive a payment for conserved land parcels irrespective of their location. Their results show the agglomeration bonus is rarely the most cost‐effective option, and when it is, it is only slightly better than one of the alternatives. This suggests that the agglomeration bonus should not be given priority as a policy design option. However, this finding is based on consideration of only 1 species. We examined whether the same applied to 2 species, one for which the homogeneous payment is best and the other for which the agglomeration payment is most cost‐effective. We modified a published conceptual model so that we were able to assess the cost‐effectiveness of payment schemes for 2 species and applied it to a grassland bird and a grassland butterfly in Germany that require the same habitat but have different spatial‐connectivity needs. When conserving both species, the agglomeration bonus was more cost‐effective than the agglomeration and the homogeneous payment; thus, we showed that as a policy the agglomeration bonus is a useful conservation‐payment option. 相似文献
22.
Frank Moser Thomas Jakl Reihard Joas Francesco Dondi 《Environmental science and pollution research international》2014,21(21):12445-12456
Chemical Leasing is a service-oriented business model that shifts the focus from increasing sales volume of chemicals towards a value-added approach. Recent pilot projects have shown the economic benefits of introducing Chemical Leasing business models in a broad range of sectors. A decade after its introduction, the promotion of Chemical Leasing is still predominantly done by the public sector and international organizations. We show in this paper that awareness-raising activities to disseminate information on this innovative business model mainly focus on the economic benefits. We argue that selling Chemical Leasing business models solely on the grounds of economic and ecological considerations falls short of branding it as a corporate social responsibility initiative, which, for this paper, is defined as a stakeholder-oriented concept that extends beyond the organization’s boundaries and is driven by an ethical understanding of the organization’s responsibility for the impact of its business activities. For the analysis of Chemical Leasing business models, we introduce two case studies from the water purification and metal degreasing fields, focusing on employees and local communities as two specific stakeholder groups of the company introducing Chemical Leasing. The paper seeks to demonstrate that Chemical Leasing business models can be branded as a corporate social responsibility initiative by outlining the vast potential of Chemical Leasing to improve occupational health and safety and to strengthen the ability of companies to protect the environment from the adverse effects of the chemicals they apply. 相似文献
23.
Refuse trucks play an important role in the waste collection process. Due to their typical driving cycle, these vehicles are characterized by large fuel consumption, which strongly affects the overall waste disposal costs. Hybrid hydraulic refuse vehicles offer an interesting alternative to conventional diesel trucks, because they are able to recuperate, store and reuse braking energy. However, the expected fuel savings can vary strongly depending on the driving cycle and the operational mode. Therefore, in order to assess the possible fuel savings, a typical driving cycle was measured in a conventional vehicle run by the waste authority of the City of Stuttgart, and a dynamical model of the considered vehicle was built up. Based on the measured driving cycle and the vehicle model including the hybrid powertrain components, simulations for both the conventional and the hybrid vehicle were performed. Fuel consumption results that indicate savings of about 20% are presented and analyzed in order to evaluate the benefit of hybrid hydraulic vehicles used for refuse collection. 相似文献
24.
Mirco Bundschuh Michael C. Newman Jochen P. Zubrod Frank Seitz Ricki R. Rosenfeldt Ralf Schulz 《Environmental science and pollution research international》2013,20(10):7341-7347
Although generally misunderstood, the p value is the probability of the test results or more extreme results given H0 is true: it is not the probability of H0 being true given the results. To obtain directly useful insight about H0, the positive predictive value (PPV) and the negative predictive value (NPV) may be useful extensions of null hypothesis significance testing (NHST). They provide information about the probability of statistically significant and non-significant test outcomes being true based on an a priori defined biologically meaningful effect size. The present study explores the utility of PPV and NPV in an ecotoxicological context by using the frequently applied Daphnia magna reproduction test (OECD guideline 211) and the chemical stressor lindane as a model system. The results indicate that especially the NPV deviates meaningfully between a test design strictly following the guideline and an experimental procedure controlling for α and β at the level of 0.05. Consequently, PPV and NPV may be useful supplements to NHST that inform the researcher about the level of confidence warranted by both statistically significant and non-significant test results. This approach also reinforces the value of considering α, β, and a biologically meaningful effect size a priori. 相似文献
25.
Uhrner U Zallinger M von Löwis S Vehkamäki H Wehner B Stratmann F Wiedensohler A 《Journal of the Air & Waste Management Association (1995)》2011,61(4):399-408
A major source of particle number emissions is road traffic. However, scientific knowledge concerning secondary particle formation and growth of ultrafine particles within vehicle exhaust plumes is still very limited. Volatile nanoparticle formation and subsequent growth conditions were analyzed here to gain a better understanding of "real-world" dilution conditions. Coupled computational fluid dynamics and aerosol microphysics models together with measured size distributions within the exhaust plume of a diesel car were used. The impact of soot particles on nucleation, acting as a condensational sink, and the possible role of low-volatile organic components in growth were assessed. A prescribed reduction of soot particle emissions by 2 orders of magnitude (to capture the effect of a diesel particle filter) resulted in concentrations of nucleation-mode particles within the exhaust plume that were approximately 1 order of magnitude larger. Simulations for simplified sulfuric acid-water vapor gas-oil containing nucleation-mode particles show that the largest particle growth is located in a recirculation zone in the wake of the car. Growth of particles within the vehicle exhaust plume up to detectable size depends crucially on the relationship between the mass rate of gaseous precursor emissions and rapid dilution. Chassis dynamometer measurements indicate that emissions of possible hydrocarbon precursors are significantly enhanced under high engine load conditions and high engine speed. On the basis of results obtained for a diesel passenger car, the contributions from light diesel vehicles to the observed abundance of measured nucleation-mode particles near busy roads might be attributable to the impact of two different time scales: (1) a short one within the plume, marked by sufficient precursor emissions and rapid dilution; and (2) a second and comparatively long time scale resulting from the mix of different precursor sources and the impact of atmospheric chemistry. 相似文献
26.
Edward D. Frank Amgad Elgowainy Jeongwoo Han Zhichao Wang 《Mitigation and Adaptation Strategies for Global Change》2013,18(1):137-158
Algae biomass is an attractive biofuel feedstock when grown with high productivity on marginal land. Hydrothermal liquefaction (HTL) produces more oil from algae than lipid extraction (LE) does because protein and carbohydrates are converted, in part, to oil. Since nitrogen in the algae biomass is incorporated into the HTL oil, and since lipid extracted algae for generating heat and electricity are not co-produced by HTL, there are questions regarding implications for emissions and energy use. We studied the HTL and LE pathways for renewable diesel (RD) production by modeling all essential operations from nutrient manufacturing through fuel use. Our objective was to identify the key relationships affecting HTL energy consumption and emissions. LE, with identical upstream growth model and consistent hydroprocessing model, served as reference. HTL used 1.8 fold less algae than did LE but required 5.2 times more ammonia when nitrogen incorporated in the HTL oil was treated as lost. HTL RD had life cycle emissions of 31,000 gCO2 equivalent (gCO2e) compared to 21,500 gCO2e for LE based RD per million BTU of RD produced. Greenhouse gas (GHG) emissions increased when yields exceeded 0.4 g HTL oil/g algae because insufficient carbon was left for biogas generation. Key variables in the analysis were the HTL oil yield, the hydrogen demand during upgrading, and the nitrogen content of the HTL oil. Future work requires better data for upgrading renewable oils to RD and requires consideration of nitrogen recycling during upgrading. 相似文献
27.
Further evidence of nuclear reactions in the Pd/D lattice: emission of charged particles 总被引:1,自引:1,他引:0
Almost two decades ago, Fleischmann and Pons reported excess enthalpy generation in the negatively polarized Pd/D-D2O system, which they attributed to nuclear reactions. In the months and years that followed, other manifestations of nuclear
activities in this system were observed, viz. tritium and helium production and transmutation of elements. In this report,
we present additional evidence, namely, the emission of highly energetic charged particles emitted from the Pd/D electrode
when this system is placed in either an external electrostatic or magnetostatic field. The density of tracks registered by
a CR-39 detector was found to be of a magnitude that provides undisputable evidence of their nuclear origin. The experiments
were reproducible. A model based upon electron capture is proposed to explain the reaction products observed in the Pd/D-D2O system.
相似文献
Pamela A. Mosier-BossEmail: |
28.
Reeve E Ndriantsoa SH Strauss A Randrianiaina RD Rasolonjatovo Hiobiarilanto T Glaw F Glos J Vences M 《Die Naturwissenschaften》2011,98(2):135-143
Acoustic communication is widespread among adult stages of terrestrial animals and fish and has also been observed in insect larvae. We report underwater acoustic communication in the larvae of a frog, Gephyromantis azzurrae, from Isalo, a sandstone massif in western Madagascar. According to our field data, these tadpoles live in streams and prefer habitats characterized by comparatively low temperatures, shallow water depth, and a relatively fast current. Feeding experiments indicated that the tadpoles are carnivorous and macrophagous. They consumed insect larvae and, to a lesser extent, small shrimps, and conspecific as well as heterospecific tadpoles. Calls of these tadpoles consisted either of single click notes or of irregular series of various clicks. Some complex calls have a pulsed structure with three to nine indistinct energy pulses. Production of the pulses coincided with rapid closure of the jaw sheaths and often with an upward movement of the body. Calls were emitted while attacking prey and occurred significantly more often when attacking conspecifics. Tadpoles that had not been fed for some time emitted sounds more frequently than those that had been regularly fed. The spectral frequency of the calls differed in tadpole groups of different size and was higher in groups of smaller tadpoles, suggesting that spectral frequency carries some information about tadpole size which might be important during competitive feeding to assess size and strength of competitors. This report differs from those for the larvae of South American horned frogs, Ceratophrys ornata. These are the only other tadpoles for which sound production has reliably been reported but the calls of Ceratophrys tadpoles occur mainly in a defensive context. 相似文献
29.
Effect of C/N ratio, aeration rate and moisture content on ammonia and greenhouse gas emission during the composting 总被引:3,自引:0,他引:3
Gaseous emission (N2O, CH4 and NH3) from composting can be an important source of anthropogenic greenhouse gas and air pollution. A laboratory scale orthogonal experiment was conducted to estimate the effects of C/N ratio, aeration rate and initial moisture content on gaseous emission during the composting of pig faeces from Chinese Ganqinfen system. The results showed that about 23.9% to 45.6% of total organic carbon (TOC) was lost in the form of CO2 and 0.8% to 7.5% of TOC emitted as CH4. Most of the nitrogen was lost in the form of NH3, which account for 9.6% to 32.4% of initial nitrogen. N2O was also an important way of nitrogen losses and 1.5% to 7.3% of initial total nitrogen was lost as it. Statistic analysis showed that the aeration rate is the most important factor which could affect the NH3 (p = 0.0189), CH4 (p = 0.0113) and N2O (p = 0.0493) emissions significantly. Higher aeration rates reduce the CH4 emission but increase the NH3 and N2O losses. C/N ratio could affect the NH3 (p = 0.0442) and CH4 (p = 0.0246) emissions significantly, but not the N2O. Lower C/N ratio caused higher NH3 and CH4 emissions. The initial moisture content can not influence the gaseous emission significantly. Most treatments were matured after 37 days, except a trial with high moisture content and a low C/N ratio. 相似文献
30.
The utilisation of Social Impact Assessment (SIA) in Iran is analysed in terms of its policy context and its application in practice. Five case studies where SIA was employed in conjunction with Environmental Impact Assessments (EIA) for agricultural development projects are evaluated. In addition, the performance of the policy context is assessed. This research revealed that there are legal and institutional constraints to the effective functioning of SIA in Iran, and that there are deficiencies in the operating guidelines. There were serious problems associated with the way SIA was undertaken in all five case studies. Recommendations to improve the policy framework for the conduct of SIA are made. The recommendations advocate for a higher profile of SIA within legislation, for social issues to have greater emphasis in official guidelines for the conduct of EIA and SIA, and for a range of measures to increase the professionalism of SIA practice. 相似文献