Environmental accounts bring together economic and environmental information in a common framework to measure the contribution of the environment to the economy and the impact of the economy on the environment. They enable governments to set priorities, monitor economic policies more precisely, enact more effective environmental regulations and resource management strategies, and design more efficient market instruments for environmental policies. This article uses examples from the regional environmental accounting programme in southern Africa to demonstrate the usefulness of environmental accounts to policy-making and natural resource management. The examples address the contribution of natural capital endowments (minerals and fisheries) to sustainable development in Botswana and Namibia; the economic importance of non-market forest goods and services in South Africa; and the socio-economic impact of current water allocation and pricing policies in Botswana, Namibia and South Africa. While there are many additional policy applications, these few provide a powerful argument for the use of environmental accounts in all countries. 相似文献
ABSTRACT The main challenge of utilizing ethanol in diesel engines in blending mode is the phase separation issue. Therefore, an attempt has been performed to enhance the stability feature of ethanol/Jatropha biodiesel (JME) blends by using n-butanol as co-solvent. The 10% by volume of n-butanol is added to the mixtures of 10% and 20% ethanol and 70% and 80% JME, which is denoted as JME10Bu10E and JME10Bu20E, respectively. The phase stability of the evaluated fuels is examined employing visual approach and Thermogravimetric analysis. These methods confirm that there is no phase separation for more than 2 months under ambient conditions. Then, the combustion and emission features are investigated utilizing a diesel engine run with different loads and constant speed. The findings demonstrate that the pmax. and HRR are increased by adding ethanol. The ignition delay is extended with the addition of ethanol while the combustion period is almost the same. The bsfc is decreased by adding ethanol compared to JME fuel. The CO, UHC, and NOx formations are reduced markedly by 40%, 40%, and 40%, respectively, with adding ethanol. Finally, using n-butanol and JME as co-solvents with ethanol supports the growth of renewable energy in the CI engine. 相似文献
To answer the difficult question of how to integrate operation of ground and surface water supplies into their management plans, the decision-makers must be able to predict the effects of various alternative modes of operation and meteorological conditions on the groundwater basin. Many types of models have been used for simulating the behavior of groundwater basins under these changes. Analog simulators, analog computers, and digital computers have been employed for model development. To achieve plausible models, detailed hydraulic and hydrologic characteristics are required, such as data on transmissivity, storage, and net deep percolation. These data are used in the equations that form the model. Water quality, which cannot be separated from quantity, deserves equal consideration. Recently, considerable efforts have been made to develop water quality prediction tools through the use of modeling techniques. 相似文献
Environmental Geochemistry and Health - Accumulation of heavy metals (HMs) in fish tissues is an important factor in monitoring the health and safety of aquatic ecosystems. Furthermore, fish are... 相似文献
Environmental Geochemistry and Health - The results of biogeochemical and bioindication studies on the resistance of natural populations of macrophyte plant—cattail (Typha australis Schum.... 相似文献
A two-dimensional steady state numerical simulation has been carried out for a typical street canyon ventilated by a cross-wind. The PHOENICS package from CHAM was used to solve for the air flow above and within the street canyon. The k-epsilon turbulence model was used for turbulence modelling and pollutant sources were added at ground level over the road but not over the pavements. Results for the air flow showed the formation of a longitudinal vortex within the street canyon, as found by other researchers. Pollutant concentrations were predicted with the highest values occurring at the leeward walls of the upwind buildings, and the lowest values on the windward walls of the downwind buildings. The accuracy of these simulations was examined by comparing the predicted results with field observations. Reasonable agreement was obtained, confirming the difference between concentrations on the leeward and windward walls. The results show that the dispersion characteristics can be simulated in terms of structural configurations. 相似文献
An optimization methodology for designing groundwater quality monitoring networks applicable to stochastic flow fields is presented and evaluated. The approach sets itself apart from previous techniques by incorporating the time dimension directly into the objective function. This function is extremized using a directed partial enumeration strategy guided by physical considerations related to transport processes. The result is a set of monitoring well locations and a sampling schedule that minimizes plume characterization error while satisfying constraints on the maximum number of wells and allowable number of active wells. The method is evaluated using hypothetical plumes with varying degrees of heterogeneity. Results indicate that the proposed approach is successful in generating near-optimal sampling networks that satisfy all imposed constraints. Monitoring networks with as little as three active wells and a total of 12 wells are found to provide adequate plume characterization for low toxicity contaminants. 相似文献
Environmental Science and Pollution Research - Solid particles impair the performance of the photovoltaic (PV) modules. This results in power losses which lower the efficiency of the system as well... 相似文献
Financial development is important for the growth of a country which indirectly affects the environment adversely through industrialization. However, in the presence of strong institutions, this adverse effect can be reduced. The main concern of the present study is to estimate the relation between CO2 and financial development (FD) in the presence of economic institutions as an interactive term. A sample of 101 countries has been selected for econometric analysis for the period from 1995 to 2017. The cross-section dependence test statistics for dependency, CIPS and CADF for panel unit root test, Westerlund test to ascertain the long-run affiliations, and FMOLS to extract the long-run coefficients have been applied. Dumitrescu and Hurlin test is also employed to know about the causal nature of the panel series. The findings show that financial development has a positive relationship with CO2. However, after inclusion of economic intuitions, the adverse impact of financial development on the environment is reduced. The study also confirms the presence of environmental Kuznets curve in the context of income and financial development. The findings imply that financial development can help to improve environment quality if it is accompanied with strong institutional framework such as assurance of property rights, government integrity, and liberalization in financial sector.
Environmental Science and Pollution Research - Potassium bromate (PB) is a commonly used food additive, a prominent water disinfection by-product, and a class IIB carcinogen. It exerts a various... 相似文献