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1.
The functions of packaging are derived from product requirements, thus for insight into the environmental effects of packaging the actual combination of product and package has to be evaluated along the production and distribution system. This extension to all related environmental aspects adds realism to the environmental analysis and provides guidance for design while preventing a too detailed investigation of parts of the production system. This approach is contrary to current environmental studies where packaging is always treated as an independent object, neglecting the more important environmental effects of the product that are influenced by packaging. The general analysis and quantification stages for this approach are described, and the currently available methods for the assessment of environmental effects are reviewed. To limit the workload involved in an environmental assessment, a step-by-step analysis and the use of feedback is recommended. First the dominant environmental effects of a particular product and its production and distribution are estimated. Then, on the basis of these preliminary results, the appropriate system boundaries are chosen and the need for further or more detailed environmental analysis is determined. For typical food and drink applications, the effect of different system boundaries on the outcome of environmental assessments and the advantage of the step-by-step analysis of the food supply system is shown. It appears that, depending on the consumer group, different advice for reduction of environmental effects has to be given. Furthermore, because of interrelated environmental effects of the food supply system, the continuing quest for more detailed and accurate analysis of the package components is not necessary for improved management of the environmental effects of packaging.  相似文献   

2.
Energy and carbon balances of wood cascade chains   总被引:1,自引:0,他引:1  
In this study we analyze the energy and carbon balances of various cascade chains for recovered wood lumber. Post-recovery options include reuse as lumber, reprocessing as particleboard, pulping to form paper products, and burning for energy recovery. We compare energy and carbon balances of chains of cascaded products to the balances of products obtained from virgin wood fiber or from non-wood material. We describe and quantify several mechanisms through which cascading can affect the energy and carbon balances: direct cascade effects due to different properties and logistics of virgin and recovered materials, substitution effects due to the reduced demand for non-wood materials when wood is cascaded, and land use effects due to alternative possible land uses when less timber harvest is needed because of wood cascading. In some analyses we assume the forest is a limiting resource, and in others we include a fixed amount of forest land from which biomass can be harvested for use as material or biofuel. Energy and carbon balances take into account manufacturing processes, recovery and transportation energy, material recovery losses, and forest processes. We find that land use effects have the greatest impact on energy and carbon balances, followed by substitution effects, while direct cascade effects are relatively minor.  相似文献   

3.
Understanding the environmental effects of alternative fuel production is critical to characterizing the sustainability of energy resources to inform policy and regulatory decisions. The magnitudes of these environmental effects vary according to the intensity and scale of fuel production along each step of the supply chain. We compare the spatial extent and temporal duration of ethanol and gasoline production processes and environmental effects based on a literature review and then synthesize the scale differences on space–time diagrams. Comprehensive assessment of any fuel-production system is a moving target, and our analysis shows that decisions regarding the selection of spatial and temporal boundaries of analysis have tremendous influences on the comparisons. Effects that strongly differentiate gasoline and ethanol-supply chains in terms of scale are associated with when and where energy resources are formed and how they are extracted. Although both gasoline and ethanol production may result in negative environmental effects, this study indicates that ethanol production traced through a supply chain may impact less area and result in more easily reversed effects of a shorter duration than gasoline production.  相似文献   

4.
Mineral development has contributed greatly to China's economic and social development. Many challenges remain, however, including environmental pollution and resource waste in practice, as well as a dearth of systematic theoretical research. The goal of this study is to analyze the economic and social effects of various mineral developments in China from diversified perspectives, so as to provide the basis for the formulation of China's mineral development policy. The input–output effects, industrial linkage effects and income distribution effects of different mining industries are quantitatively analyzed by adopting basic hypotheses of input–output economics, industrial linkage model and income distribution antitheses based on the latest available official data from China Statistical Yearbook from 2004 to 2010 and the 2007 Input–Output Table of China. The empirical results obtained in this study indicate that all mineral development industries, especially coal mining and washing, and petroleum and natural gas extraction industries, have given a strong impetus to the increase of China's fixed asset investment and GDP. Moreover, they have provided a large number of jobs, thereby alleviating ongoing employment pressure, and they have also played a positive role in promoting China's technology investment. The analysis of industrial linkages demonstrates that mining industries are basic to the national economy and produce a significant impetus to its downstream industries, but create weak pull effects in terms of national economic development. From the perspective of income distribution, mining industries play an important role in increasing China's fiscal revenue and per capital income. Hence, China's mineral development policy should (1) encourage additional investment in technology for exploration and development to insure sufficient supply and expand the input effects; (2) attract additional talent to work in remote regions; (3) optimize the industrial structure and promote the industrial transformation in resource regions; (4) adjust the interest distribution between the central and local governments to enable the local regions to become more self-sufficient; and (5) enhance the legal environment so that companies can more readily undertake their social responsibilities voluntarily.  相似文献   

5.
Matching biological and chemical data were compiled from numerous modeling, laboratory, and field studies performed in marine and estuarine sediments. Using these data, two guideline values (an effects range-low and an effects range-median) were determined for nine trace metals, total PCBs, two pesticides, 13 polynuclear aromatic hydrocarbons (PAHs), and three classes of PAHs. The two values defined concentration ranges that were: (1) rarely, (2) occasionally, or (3) frequently associated with adverse effects. The values generally agreed within a factor of 3 or less with those developed with the same methods applied to other data and to those developed with other effects-based methods. The incidence of adverse effects was quantified within each of the three concentration ranges as the number of cases in which effects were observed divided by the total number of observations. The incidence of effects increased markedly with increasing concentrations of all of the individual PAHs, the three classes of PAHs, and most of the trace metals. Relatively poor relationships were observed between the incidence of effects and the concentrations of mercury, nickel, total PCB, total DDT and p,p′-DDE. Based upon this evaluation, the approach provided reliable guidelines for use in sediment quality assessments. This method is being used as a basis for developing National sediment quality guidelines for Canada and informal, sediment quality guidelines for Florida. The methods and guidelines presented in this report do not necessarily represent the policy of the National Oceanic and Atmospheric Administration, Environment Canada, or Florida Department of Environmental Protection.  相似文献   

6.
Biochar derived from pyrolysis has received much attention recently as a soil additive to sequester carbon and increase soil fertility. Hydrochar, a brown, coal-like substance produced via hydrothermal carbonization, has also been suggested as a beneficial soil additive. However, before soil application, both types of char need to be tested for potential toxic effects. The aim of this study was to develop simple, inexpensive, and easy-to-apply test procedures to identify negative effects of chars but not to provide false-negative results. The following tests, based partly on ISO norm biotoxicity test procedures, were chosen: (i) cress germination test for gaseous phytotoxic emissions; (ii) barley germination and growth test; (iii) salad germination test; and (iv) earthworm avoidance test for toxic substances. Test reproducibility was ensured by carrying out each test procedure three times with the same biochar. Several modifications were necessary to adapt the tests for biochars/hydrochars. The tested biochar did not induce negative effects in any of the tests. In contrast, the beet-root chip hydrochar showed negative effects in all tests. In an extension to the regular procedure, a regrowth of the harvested barley shoots without further nutrient additions yielded positive results for the hydrochar, which initially had negative effects. This implies that the harmful substance(s) must have been degraded or they were water soluble and leached. Tests with a biochar and hydrochar showed that the proposed modified quick-check test procedures provide a fast assessment of risks and effects of char application to soils within a short period of time (<2 wk).  相似文献   

7.
Riprap, consisting of large boulders or concrete blocks, is extensively used to stabilize streambanks and to inhibit lateral erosion of rivers, yet its effect on river morphology and its ecological consequences have been relatively little studied. In this paper, we review the available information, most of it culled from the “grey” literature. We use a simple one‐dimensional morphodynamic model as a conceptual tool to illustrate potential morphological effects of riprap placement in a gravel‐bed river, which include inhibition of local sediment supply to the channel and consequent channel bed scour and substrate coarsening, and downstream erosion. Riprap placement also tends to sever organic material input from the riparian zone, with loss of shade, wood input, and input of finer organic material. Available information on the consequences for the aquatic ecosystem mainly concerns effects on commercially and recreationally important fishes. The preponderance of studies report unfavorable effects on local numbers, but habitat niches created by openings in riprap can favorably affect invertebrates and some small fishes. There is a need for much more research on both morphological and ecosystem effects of riprap placement.  相似文献   

8.
研究红阳猕猴桃、葛根及其配方组合物的解酒保肝与抗氧化作用。采用乙醇所致小鼠自主活动减少和小鼠共济失调实验评价解酒作用;采用小鼠酒精性肝损伤模型评价保肝作用,采用ELISA测定大鼠尿液中8-羟基脱氧鸟苷酸(8-hydroxy-2-deoxyguanosine,8-OHdG)和乙酰—赖氨酸加合物(hexanoyl-lysine adduct,HEL),以了解配方组合物对DNA过氧化和脂质过氧化的影响。结果表明,红阳猕猴桃—葛根配方可减轻酒精所致小鼠行为抑制和共济失调,提示具有解酒作用;对酒精所致小鼠肝脏MDA、TG水平升高和GSH水平降低有明显改善,提示具有保护化学性肝损伤作用;降低正常和酒精损伤大鼠尿液中过氧化生物标志物水平,提示具有较好的抗氧化作用。红阳猕猴桃—葛根配方具有快速解酒作用,且可持续2—4h;对酒精性肝损伤有一定的保护作用,其机制与抗氧化有关。  相似文献   

9.
Abstract: The synthetic biocides triclosan (5‐chloro‐2‐(2,4‐dichlorophenoxy)phenol) and triclocarban (3,4,4′‐trichlorocarbanilide) are routinely added to a wide array of antimicrobial personal care products and consumer articles. Both compounds can persist in the environment and exhibit toxicity toward a number of biological receptors. Recent reports of toxicological effects in wildlife, human cell cultures, and laboratory animals have heightened the interest in the occurrence of these biocide and related toxic effects. The present study aimed to summarize published environmental concentrations of biocides and contrast them with toxicity threshold values of susceptible organisms. Environmental occurrences and toxicity threshold values span more than six orders of magnitude in concentration. The highest biocide levels, measured in the mid parts‐per‐million range, were determined to occur in aquatic sediments and in municipal biosolids destined for land application. Crustacea and algae were identified as the most sensitive species, susceptible to adverse effects from biocide exposures in the parts‐per‐trillion range. An overlap of environmental concentrations and toxicity threshold values was noted for these more sensitive organisms, suggesting potential adverse ecological effects in aquatic environments. Affirmative evidence for this is lacking, however, since studies examining environmental occurrences of biocides vis‐à‐vis the health and diversity of aquatic species have not yet been conducted.  相似文献   

10.
一个完善的制度是保证旅游业持续发展的关键.在新制度经济理论的指导下和界定制度变迁相关概念的基础上,分析了制度变迁对旅游发展的效应.从制度变迁对旅游发展是否存在效应、正效应还是负效应、具体效应与不同区域的效应有无差异等方面构建了研究框架和主要内容.  相似文献   

11.
We propose a method for the appropriate assessment of adverse effects of roads in compliance with the European Union Habitats Directive. The method incorporates an analysis of ecological risk of edge effects by the proposed roads with the related increase in accessibility. The method was tested on 30 km of planned forest roads inside an 8,000-ha reserve included in two Natura 2000 sites. As a result, the cumulative effect of 19 road segments was judged as not significantly affecting the integrity of the sites, although they made accessible an extra 314 ha. On the basis of the accessibility calculation, 20 ha of land were set aside from forest exploitation as a mandatory mitigation measure. The method objectively determined the cumulative adverse effects, enabled comparison of plan revisions and alternatives and proved to measure direct and indirect significant effects with a realistic effort in terms of field survey and geographic information system processing.  相似文献   

12.
In developing countries, large dam projects continue to be launched, primarily to secure a time-stable freshwater supply and to generate hydropower. Meanwhile, calls for environmentally sustainable development put pressure on the dam-building industry to integrate ecological concerns in project planning and decision-making. Such integration requires environmental impact statements (EISs) that can communicate the societal implications of the ecological effects in terms that are understandable and useful to planners and decision-makers. The purpose of this study is to develop a basic framework for assessing the societal implications of the river ecological effects expected of a proposed large dam project. The aim is to facilitate a comparison of desired and potential undesired effects on-site and downstream. The study involves two main tasks: to identify key river goods and services that a river system may provide, and to analyze how the implementation of a large dam project may alter the on-site capacity and downstream potentials to derive river goods and services from the river system. Three river goods and six river services are identified. River goods are defined as extractable partly man-made products and river services as naturally sustained processes. By four main types of flow manipulations, a large dam project improves the on-site capacity to derive desired river goods, but simultaneously threatens the provision of desirable river goods and services downstream. However, by adjusting the site, design, and operational schedule of the proposed dam project, undesirable effects on river goods and services can be minimized.  相似文献   

13.
日历效应是旅游活动在年内变化的时间节律,主要体现在季节效应、节日效应和周末效应。基于景区级别—旅游客流量模型,收集新疆吐鲁番4景区连续3年的逐日客流量数据,通过构建3个指数模型测算效应值,以分析景区级别与日历效应之间的关系。结果发现:吐鲁番旅游淡旺季特别明显,景区级别越高,淡旺季差异越大;五一和国庆节日效应最高,景区级别越低,节日效应越显著,长假期有明显的节前和节后效应;周末效应有明显的季节性差异,周六效应高于周日效应,景区级别越低,周末效应越高。最后,从气候变化、节假日制度和作息制度探讨了旅游日历效应的成因。  相似文献   

14.
In Southeast Asia the aquatic macrophyte water spinach (Ipomoea aquatica Forsk.) is a popular vegetable that is cultivated in freshwater courses. These often serve as recipients for domestic and other sorts of wastewater that often contain a variety of pollutants, such as heavy metals. In addition, fertilizers are frequently used where water spinach is cultivated commercially for the food market. To estimate the importance of ambient nutrient concentrations for accumulation of mercury (Hg), cadmium (Cd), and lead (Pb) in water spinach, plants were exposed to nutrient solutions of different strength and with varying metal concentrations. Metal-induced toxic effects, which might possibly affect the yield of the plants, were also studied. The lower the nutrient strength in the medium was, the higher the metal concentrations that accumulated in the different plant parts and the lower the metal concentration in the medium at which metal-induced toxic effects occurred. Accordingly, internal metal concentrations in the plants were correlated to toxic effects. Plants exposed to metals retained a major proportion of the metals in the roots, which had a higher tolerance than shoots for high internal metal concentrations.  相似文献   

15.
We conducted a field experiment using constructed communities to test whether species richness contributed to the maintenance of ecosystem processes under fire disturbance. We studied the effects of diversity components (i.e., species richness and species composition) upon productivity, structural traits of vegetation, decomposition rates, and soil nutrients between burnt and unburnt experimental Mediterranean grassland communities. Our results demonstrated that fire and species richness had interactive effects on aboveground biomass production and canopy structure components. Fire increased biomass production of the highest-richness communities. The effects of fire on aboveground biomass production at different levels of species richness were derived from changes in both vertical and horizontal canopy structure of the communities. The most species-rich communities appeared to be more resistant to fire in relation to species-poor ones, due to both compositional and richness effects. Interactive effects of fire and species richness were not important for belowground processes. Decomposition rates increased with species richness, related in part to increased levels of canopy structure traits. Fire increased soil nutrients and long-term decomposition rate. Our results provide evidence that composition within richness levels had often larger effects on the stability of aboveground ecosystem processes in the face of fire disturbance than species richness per se.  相似文献   

16.
The present review aims to summarize current knowledge in the topic of wood ash application to boreal forest and aquatic ecosystems, and the different effects derived from these actions. Much research has been conducted regarding the effects of wood ash application on forest growth. Present studies show that, generally speaking, forest growth can be increased on wood ash-ameliorated peatland rich in nitrogen. On mineral soils, however, no change or even decreased growth have been reported. The effects on ground vegetation are not very clear, as well as the effects on fungi, soil microbes, and soil-decomposing animals. The discrepancies between different studies are for the most part explained by abiotic factors such as variation in fertility among sites, different degrees of stabilization, and wood ash dosage used, and different time scales among different studies. The lack of knowledge in the field of aquatic ecosystems and their response to ash application is an important issue for future research. The few studies conducted have mainly considered changes in water chemistry. The biotoxic effects of ash application can roughly be divided into two categories: primary and secondary. Among the primary effects is toxicity deriving from compounds in the wood ash and cadmium is probably the worst among these. The secondary effects of wood ash are generally due to its alkaline capacity and a release of ions into the soil and soil water, and finally, watercourses and lakes. Given current knowledge, we would recommend site- and wood ash-specific application practices, rather than broad and general guidelines for wood ash application to forests.  相似文献   

17.
全氟化合物的分布、累积及生态毒理学效应   总被引:1,自引:0,他引:1  
全氟化合物(Perfluorinated compounds,PFCs)污染在全球范围内已普遍存在,其在环境中的浓度增长迅速,受到人们越来越多的关注。环境中PFCs的迁移转化规律决定其环境效应,是进行环境和健康风险评价的基础。目前关于PFCs的研究主要集中于水体及生物体内PFCs的分析检测,对其生态毒理效应的研究尚处于初步阶段。本文介绍了PFCs研究现状,综述了PFCs在环境中的分布模式、生物体内的蓄积规律以及环境中PFCs的生态毒理效应等方面的最新研究进展,同时也阐述了PFCs污染对人体健康的影响,并提出了未来PFCs研究亟待解决的问题。  相似文献   

18.
This paper presents an assessment of the potential impact of the EUs biofuel directive on European land use and biodiversity. In a spatially explicit analysis, it is determined which ecologically valuable land use types are likely to be directly replaced by biofuel crops. In addition, it is determined which land use types may be indirectly replaced by biofuel crops through competition over land between biofuel and food crops. Four scenarios of land use change are analyzed for the period 2000–2030 while for each scenario two policy variants are analyzed respectively with and without implementation of the biofuel directive. The results indicate that the area of semi natural vegetation, forest and High Nature Value farmland directly replaced by biofuel crops is small in all scenarios and differs little between policy variants. The direct effects of the directive on European land use and biodiversity therefore are relatively minor. The indirect effects of the directive on European land use and biodiversity are much larger than its direct effects. The area semi natural vegetation is found to be 3–8% smaller in policy variants with the directive as compared to policy variants without the directive. In contrast, little difference is found between the policy variants with respect to the forest area. The results of this study show that the expected indirect effects of the directive on biodiversity are much greater than its direct effects. This suggests that indirect effects need to be taken explicitly into account in assessing the environmental effects of biofuel crop cultivation and designing sustainable pathways for implementing biofuel policies.  相似文献   

19.
三氯杀螨醇的雌激素效应及其机制的研究进展   总被引:5,自引:0,他引:5  
梁刚  唐超智 《四川环境》2004,23(5):54-56,71
三氯杀螨醇(dicofol,DCF)是现代农牧业生产中广泛使用的一种杀虫剂,许多实验证据表明它对动物和人体有雌激素效应,如导致美洲鳄(Alligator mississippiensis)发生雌性化现象、使美洲鹰(Falco sparverius)的卵壳变薄、引起小鼠子宫增重、促进人类乳癌细胞(MCF7)增殖等。有关它的作用机制研究目前主要集中在下丘肛-垂体-性腺轴中的激素受体上,本文对DCF的雌激素效应及其作用机制研究进展做了回顾。  相似文献   

20.
Estuarine dredge and fill activities: A review of impacts   总被引:1,自引:0,他引:1  
Dredge and fill activities in estuaries have many environmental effects, most, although not all, of them deleterious. These effects include reduced light penetration by increased turbidity; altered tidal exchange, mixing, and circulation; reduced nutrient outflow from marshes and swamps; increased saltwater intrusion; and creation of an environment highly susceptible to recurrent low dissolved oxygen levels. Coral, oysters, and barnacles are particularly vulnerable to the effects of siltation. Both estuarine flora and fauna may be harmed by contaminants released into the water column by dredging operations. Ways to mitigate the effects of dredge and fill operations include careful pre- and post-construction environmental studies; use of bridging to create roadbeds where coastal wetlands cannot be avoided; use of a turbidity diaper and other means to control turbidity; dredging during periods of low benthic populations or during tides that would carry coarser sediments away from productive areas such as oyster reefs; and thoughtful disposal of spoil, such as locating spoil sites on the uplands with proper diking.  相似文献   

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