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This work analyzes hierarchical and causal relationship between worldview, institutions, technology and economic behaviour under conditions of informational uncertainty.

In our pursuit of sustainable living, institutions function both as constraints and as primary instruments of change of socio-economic behaviour. The process of radical institutional change is contingent upon prior change in the dominant worldview, while its dynamics resembles that of a paradigm change in political and scientific arenas. Therefore, the timely and adaptive outcome of institutional change with respect to global environmental problems remains intrinsically uncertain.  相似文献   
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Environment Systems and Decisions - Organizational and technical approaches have proven successful in increasing the performance and preventing risks at socio-technical systems at all scales....  相似文献   
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The Brazilian Amazon has about 69 % of available freshwater in Brazil, an amount that ends up creating the illusion that no lack of water and not lacking in the region, the large supply of this resource becomes a problem when it comes to the Management and Planning Water Resources in the Amazon, according to the wasteful use and lack of maintenance of stocks, compounded by the release of untreated wastewater. Speaking of water conservation programs in the Amazon a few decades ago and still today, with less intensity, is somewhat strange, given the large amount of water available and the culture of abundance. Thus, this research discusses the importance of the use of rainwater for non-potable purposes, since the potential for exploitation, throughout the year, due to this high rainfall in the Amazon region, ranging from, on average, 119.6 mm in months from November to 441.6 mm in March. The methods used for sizing of the reservoir were the Rippl and interactive, and economic viability checking done by the methods of net present value and discounted payback. As a result, there was a volume exceeding 1,000 m³ obtained by the method of Rippl, while the interactive method was a maximum of 75 m³. The economic viability presented fragile as a function of time to return exceeds the useful life of the utilization system for rainwater.  相似文献   
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The global animal food chain has a large contribution to the global anthropogenic greenhouse gas (GHG) emissions, but its share and sources vary highly across the world. However, the assessment of GHG emissions from livestock production is subject to various uncertainties, which have not yet been well quantified at large spatial scale. We assessed the uncertainties in the relations between animal production (milk, meat, egg) and the CO2, CH4, and N2O emissions in Africa, Latin America and the European Union, using the MITERRA-Global model. The uncertainties in model inputs were derived from time series of statistical data, literature review or expert knowledge. These model inputs and parameters were further divided into nine groups based on type of data and affected greenhouse gas. The final model output uncertainty and the uncertainty contribution of each group of model inputs to the uncertainty were quantified using a Monte Carlo approach, taking into account their spatial and cross-correlation. GHG emissions and their uncertainties were determined per livestock sector, per product and per emission source category. Results show large variation in the GHG emissions and their uncertainties for different continents, livestock sectors products or source categories. The uncertainty of total GHG emissions from livestock sectors is higher in Africa and Latin America than in the European Union. The uncertainty of CH4 emission is lower than that for N2O and CO2. Livestock parameters, CH4 emission factors and N emission factors contribute most to the uncertainty in the total model output. The reliability of GHG emissions from livestock sectors is relatively high (low uncertainty) at continental level, but could be lower at country level.  相似文献   
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Studies of the Slovakian Danube have indicated profound changes in the structures of several invertebrate assemblages in the section of the river bypassed by the Gab?íkovo hydroelectric project in 1992 and in adjacent floodplain water bodies. The present study investigates the relationship between hydrological connectivity and species diversity in the old main channel and adjacent left-bank water bodies, using resident cladocerans as indicators of the ecological integrity of the river-floodplain system. The work aimed to quantify cladoceran habitat preferences using habitat values (HV) and indication weights (IW) calculated from data accumulated during long-term monitoring of planktonic communities of the Danube floodplain (1,840.5–1,804 rkm) and supplemented with data from the literature. Although not listed as an indicator group in the European Union Water Framework Directive, cladocerans are shown to be highly apposite in the ecological assessment of river-floodplain systems. Of 71 recorded cladoceran species, 19 taxa showed a preference for eupotamal habitats, 24 species preferred eupotamal B/parapotamal waters, and 28 cladocerans were found to prefer the plesiopotamal/paleopotamal habitat type. Identified habitat types follow a gradient of hydrological connectivity with the main river channel, ranging from the eupotamal to more or less isolated floodplain water bodies. A secondary aim was to use the calculated values to assess the ecological integrity of the river-floodplain system. The key element of this procedure is the calculation of the Floodplain Index (FI) (Chovanec et al. Large Rivers, 15(1–4), 169–185 2005) from the summation of the habitat values and indication weights of all species present at the sampling sites. Calculated index values indicate the extent of disruption to lateral connectivity in the floodplain area.  相似文献   
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A preliminary bench-scale study of parallel University of Cape Town (UCT) biological nutrient removal systems showed improvement in anoxic denitrification rates resulting from prefermentation of a septic (i.e., high volatile fatty acid [VFA] content), phosphorus-limited (i.e., total chemical oxygen demand/total phosphorus [TP] ratio < 40:1) wastewater. Net phosphorus removals due to enhanced biological phosphorus removal (EBPR) were only improved marginally by prefermentation in spite of significant increases in anaerobic phosphorus release, polyhydroxyalkanoate formation, and higher anoxic and aerobic uptakes. This probably was due to the high VFA/TP ratio in the raw influent relative to the VFA requirements for EBPR because enough VFAs were already present for phosphorus removal prior to prefermentation. An additional assessment of prefermentation using parallel UCT systems with step feed of 50% of the influent to the anoxic zone was completed. This second phase quantified the effect of prefermentation in a step-feed scenario, which prioritized prefermentation use to enhance denitrification rather than EBPR. While specific denitrification rates in the anoxic zone were significantly improved by prefermentation, high denitrification in the clarifiers and aerobic zones (simultaneous denitrification) made definitive conclusions concerning the potential improvements in total system nitrogen removal questionable. The prefermented system always showed superior values of the zone settling velocity and sludge volume index and the improvement became increasingly statistically significant when the prefermenter was performing well.  相似文献   
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