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71.
We investigated the reliability and stability of favourite place selections and evaluations of place attachment over a 10-month period. A simple random sample of 1273 respondents representative of the population of the two largest cities in Finland completed a mailed questionnaire. Reliability data was obtained in a second questionnaire (N = 427). We obtained five main favourite place types which were extensively managed natural settings (mainly urban woodlands), urban green spaces (mostly parks), waterside environments, exercise and activity/hobby areas, and indoor and outdoor urban areas. Sixty-four percent of the respondents in the second survey selected the same main favourite place type as 10 months earlier, which is more than what might be expected by chance. Extensively managed natural settings (mainly urban woodlands) and waterside environments were reselected most often. Indoor and outdoor urban favourite places had the lowest stability. We found evidence of people being more consistent in their attachment to natural favourite places than to urban favourite places. The findings lend further credence and credibility to earlier results concerning self-regulation and restorative experiences in favourite places.  相似文献   
72.
The idea that trading is more costly the thinner the market is is common in most studies of market exchange with frictions. Surprisingly, this element is lacking from previous attempts to allow for frictions in pollution permit markets. This paper considers a CO2 cap-and-trade model where trading costs develop endogenously as a function of the market size. The pre-trade allocation of permits determines whether the market size can be strongly influenced by expectations that have a role because of adjustment costs. The pre-trade allocation also sets preconditions for endogenously vanishing trading costs and thus has nonstandard effects on long-run trading levels and market allocations.  相似文献   
73.
We reviewed the current methods for calculatingcritical loads of acidity for forest soils. The consequencesof four sets of assumptions concerning the soil modelstructure, parameter values and the critical loads criterionwere explored by comparing the values of the averageaccumulated exceedance (AAE) calculated for Finland withdeposition values for the year 1995. The AAE index is given inthe unit of deposition and is a measure of how far a region isfrom being protected in terms of fulfilling a certaincriterion, taking into account the size of the ecosystem areas.Using a critical limit for the molar ratio of theconcentrations of base cations to aluminium in soil solutiongave the lowest average accumulated exceedance. Assumingorgano-aluminium complexes and leaching of organic anions gaveAAE = 4 eq ha-1 a-1, which was close to the valueobtained with the standard approach used in Finland, assuminggibbsite equilibrium and no leaching of organic anions,yielding AAE = 5 eq ha-1 a-1. With a critical basesaturation limit, instead of the concentrations criterion, theAAE index was 17 eq ha-1 a-1. The highest averageaccumulated exceedance (AAE = 25 eq ha-1 a-1),corresponding to the lowest critical load, was obtained whenthe effects-based criterion (critical concentration or criticalbase saturation) was substituted with one restricting thedeterioration of the neutralizing capacity of the soil, ANC le(crit) = 0. These tests illustrate the variabilityof the critical load values for acidity that can be introducedby changing the criterion or by varying the calculation method,without, however, representing the extreme values of criticalloads that could be derived.  相似文献   
74.
Industrial symbiosis (IS) studies the physical flows of materials and energy in local industrial systems using a systems approach. In this study the total fuel and energy use, and greenhouse gas emissions are calculated for an ‘industrial park’ operating in the same manner as an IS. Moreover the relevance of industrial symbiosis, particularly one centred on pulp and paper manufacturing, in moving towards more sustainable fuel consumption and reduced greenhouse gas emissions is discussed. The system is compared to hypothetical stand-alone production. Moreover, possibilities to reduce the energy use and total greenhouse gas emissions of the park are identified.  相似文献   
75.
Determining human exposure to suspended particulate concentrations requires measurements that quantify different particle properties in microenvironments where people live, work, and play. Particle mass, size, and chemical composition are important exposure variables, and these are typically measured with time-integrated samples on filters that are later submitted to laboratory analyses. This requires substantial sample handling, quality assurance, and data reduction. Newer technologies are being developed that allow in-situ, time-resolved measurements for mass, carbon, sulfate, nitrate, particle size, and other variables. These are large measurement systems that are more suitable for fixed monitoring sites than for personal applications. Human exposure studies need to be designed to accomplish specific objectives rather than to serve too many purposes. Resources need to be divided among study design, field sampling, laboratory analysis, quality assurance, data management, and data analysis phases. Many exposure projects allocated too little to the non-measurement activities.  相似文献   
76.
Environmental Science and Pollution Research - Rivers act as a natural source of greenhouse gases (GHGs). However, anthropogenic activities can largely alter the chemical composition and microbial...  相似文献   
77.
Summary.  We examined the effects of defoliation con-currently with elevated temperature and CO2 on some chemical and morphological characteristics in the leaves of silver birch seedlings (Betula pendula). We also analyzed the consequent changes in the palatability of leaves for adult blue alder leaf beetles (Agelastica alni). Under the different climatic treatments, the seedlings were subjected to three fertilizer treatments (0 kg, 130 kg and 270 kg N ha−1) and defoliation treatments (0%, 25% and 50% of the total leaf area). In each climatic treatment, fertilization increased the nitrogen content in the leaves, but decreased total concentrations of soluble phenolics, detected by high-performance liquid chromatography (HPLC), and insoluble condensed tannins. Defoliation, both independently and in combination with elevated temperature and CO2, decreased the concentrations of the phenolics. Compared to the intact controls, the leaves of the defoliated seedlings were smaller and tougher. Under elevated temperature, the beetles consumed a smaller amount of the leaves of plants subjected to the high fertilization, while under ambient climatic conditions, fertilization increased the feeding. The total leaf consumption was higher under the ambient climatic conditions than under elevated temperature, elevated CO2 or the combination of elevated temperature and CO2.  相似文献   
78.
This paper presents the results of life cycle inventory (LCI) analyses that were carried out to determine the environmental impacts (emissions, resource extractions and land use) of different newspaper waste management options for the Helsinki Metropolitan Area (HMA). LCI analyses were performed for five product systems, in which discarded newspapers were divided into two streams: separately collected newspapers and newspapers in mixed waste. In all the options, the manufacturing and printing processes of newspaper were kept unchanged. The waste management alternatives included combinations of material recycling, energy recovery and landfilling. These product systems were modelled using the current collection rate of newspaper and four additional collection rates. The LCIs of the product systems showed that the life cycle phase causing the most environmental impacts was the paper mill. When comparing the different waste management systems, the energy recovery options were in general superior to landfilling. The ecological implications of the increased energy recovery and decreased material recycling of newspaper were, however, not yet considered in the study. These aspects were assessed in the life cycle impact assessment (LCIA), which was performed after the LCI phase.  相似文献   
79.
Kummu M  Penny D  Sarkkula J  Koponen J 《Ambio》2008,37(3):158-163
It has been claimed that Tonle Sap Lake is rapidly filling with sediment as a result of increasing sediment yields from the catchment. Infilling of the lake basin would have serious implications for the magnitude of flooding in central Cambodia and the Mekong Delta region and threaten the lake's unique ecosystem. In this article, we synthesize the results of radiocarbon dating of sediment cores and hydrodynamic modeling results to provide an empirically based assessment of this issue. We find that current sedimentation rates within the lake basin proper are low and have been for several millennia. However, sedimentation at the lake margin and in its floodplain is relatively high, which presents a range of issues for riparian communities.  相似文献   
80.
This article describes a process of developing socio-cultural indicators to support local and regional decision-making for eco-efficiency. Although eco-efficiency is calculated using environmental and economic variables, decisions on local and regional levels cannot ignore the socio-cultural impacts. The indicators were developed by a participatory process that was based on involvement and empowerment of local actors. The process ensured policy relevance and meaningful indicators and advanced their future use in the decision-making.  相似文献   
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