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1.
For the development process in the rapidly growing economies, knowledge transfer and technology cooperation are becoming important issues. Research and technological competences are key indicators for the absorptive capacity of sustainability technologies and for the ability to export them. These issues are analyzed empirically for Brazil, Russia, India, China and South Africa (BRICS). Sustainability related research in BRICS is mostly carried out within broader, more sector oriented programmes. Specialization patterns of international patents and in foreign trade indicate various strengths and weaknesses of the BRICS countries. The differences within the countries imply that the analysis must proceed at a technology specific level. China has considerable capabilities in technologies such as photovoltaics, solar thermal or buildings. There is a strong need for strategic positioning of the countries and for coordination of the various policy fields involved.  相似文献   

2.
《Environment international》1999,25(2-3):191-207
The FA and HA fractions represent 20 to 50% of the DOC of the original samples, depending on the origin, and serve as reference materials. The original aqueous samples and the aqueous solutions of the reference materials were characterized with methods suited for measuring samples at natural concentrations. The DOC normalized values of the spectral absorbances (λ = 254 nm; λ = 436 nm) in the original water samples were highest for the brown water and brown coal water and lowest for the secondary effluents. The FA fractions were similar in the UV-absorbance with the exception of the low-absorbing groundwater FA, reflecting a low density of double bonds. The DOC-normalized proton capacity of the FA fractions (10 to 20 μmol/mg) was highest for the brown coal, brown water, and soil-derived samples and again lowest for the groundwater FA. The high values are due to a higher contribution of the weak acids of phenolic type. Specific data for copper complexation capacity (0.5 to 2.5 μmol/mg) went parallel to the proton capacity. The characterization of the FAs by gel chromatography with organic carbon detection revealed three major fractions. The refractory part at short retention time dominated in the brown water and soil-derived samples, whereas the fractions for the lower molecular mass acids at long retention times were dominant in the secondary effluent and the brown coal isolate. Comparison with UV-detected chromatograms revealed a strong decrease in the specific absorbance of the secondary effluent. Up to 3% of the total mass of the FAs could be identified as hydrolyzable amino acids with the highest yield in the sample from secondary effluent and the lowest one in the groundwater sample. The nitrogen content was always higher in the FAs compared to the HAs of the same origin. The application of gel chromatography fluorescence and fluorescence decay time distribution analysis turned out to be a useful tool to differentiate between the different fractions of NOM, the isolates obtained by different methods (e.g., XAD-8, membrane separation) and the fractions of the samples from different origin and age. This is of special value, for the information can also be obtained for samples with natural NOM concentrations, even though further investigations required for full understanding of the data. This work is part of a multi-disciplinary research program (ROSIG: Refraktäre Organische Säuren in Gewässern), funded by the German Research Association (DFG).  相似文献   

3.
This paper presents an empirical study of schooling attendance and collection of environmental resources using cross-sectional data from Kiambu District of Kenya. Because the decision to collect environmental resources and attend school is jointly determined, we used a bivariate probit method to model the decisions. In addition, we corrected for the possible endogeneity of resource-collection work in the school attendance equation by using instrumental variable probit estimation. One of the key findings is that being involved in resource collection reduces the likelihood of a child attending school. The result supports the hypothesis of a negative relationship between children working to collect resources and the likelihood that they will attend school. The results further show that a child’s mother’s involvement in resource collection increases school attendance. In addition, although there is no school attendance discrimination against girls, they are overburdened by resource-collection work. The study recommends immediate policy interventions focusing on the provision of public amenities, such as water and fuelwood.  相似文献   

4.
Urbanization is the dominant form of land-use change in terms of impacts on water quality, hydrology, physical properties of watersheds and their nonpoint source (NPS) pollution po-tential at present. Urbanization has changed the source, process and sink of urban NPS pollution, especially raised the pollution load of urban runoff NPS in receiving water. Urban runoff pollution is a hot spot of research on NPS. This paper analyzed type, source and harm of the NPS pollutants of urban runoff and its influence on the receiving water. Through estimating NPS pollution load of urban runoff and summarizing the law and characteristics of urban runoff NPS systemically, study on management and control of urban runoff NPS pollution was focused on the application of BMPs (best management practices). It is a fresh methodology that management and control on NPS pollution from urban surface runoff was analyzed by methods of landscape ecology, environmental economics and environmental management. The paper provided a scientific reference for mitigating urban water environment pressure and an effective method for management and control of NPS pollution from urban surface runoff.  相似文献   

5.
The food supply to a large metropolis such as Paris involves huge fluxes of goods, which considerably impact the surrounding rural territories. Here, we present an attempt to localise Paris food supply areas, over a period of two centuries (1786, 1886, 2006), based on the analysis of data from transportation and production statistics for cereals, animal products, and fruits and vegetables, all three categories being expressed in terms of their nitrogen (i.e. protein) content. The results show contrasting trends for the three types of agricultural products. As for cereals, the Paris supply area remained for the most part restricted to the central area of the Paris basin, a region which gradually became specialised in intensive cereal production. Conversely, as animal farming had been progressively excluded from this area, regions located west and north of Paris (Brittany, Normandy, Nord-Pas-de-Calais) gradually dominated the supply of animal products to the metropolis. In addition, imported feed from South America today contributes as much as one-third of the total ration of feed in the livestock raised in these regions. For fruits and vegetables, about one-half of the Paris supply currently comes from long-distance imports, the other half coming from areas less than 200 km from Paris. As a whole, the Paris food supply area, although it has obviously enlarged in recent periods, is still anchored to an unexpected extent (about 50%) in its traditional nearby hinterland roughly coinciding with the Seine watershed, and in the regions specialised in animal farming located west and north. On the other hand, the agricultural system of the main food supply areas has considerably opened to global markets.  相似文献   

6.
BackgroundEvidence on health effects of ultrafine particles (UFP) is still limited as they are usually not monitored routinely. The few epidemiological studies on UFP and (cause-specific) mortality so far have reported inconsistent results.ObjectivesThe main objective of the UFIREG project was to investigate the short-term associations between UFP and fine particulate matter (PM) < 2.5 μm (PM2.5) and daily (cause-specific) mortality in five European Cities. We also examined the effects of PM < 10 μm (PM10) and coarse particles (PM2.5–10).MethodsUFP (20–100 nm), PM and meteorological data were measured in Dresden and Augsburg (Germany), Prague (Czech Republic), Ljubljana (Slovenia) and Chernivtsi (Ukraine). Daily counts of natural and cardio-respiratory mortality were collected for all five cities. Depending on data availability, the following study periods were chosen: Augsburg and Dresden 2011–2012, Ljubljana and Prague 2012–2013, Chernivtsi 2013–March 2014. The associations between air pollutants and health outcomes were assessed using confounder-adjusted Poisson regression models examining single (lag 0–lag 5) and cumulative lags (lag 0–1, lag 2–5, and lag 0–5). City-specific estimates were pooled using meta-analyses methods.ResultsResults indicated a delayed and prolonged association between UFP and respiratory mortality (9.9% [95%-confidence interval: − 6.3%; 28.8%] increase in association with a 6-day average increase of 2750 particles/cm3 (average interquartile range across all cities)). Cardiovascular mortality increased by 3.0% [− 2.7%; 9.1%] and 4.1% [0.4%; 8.0%] in association with a 12.4 μg/m3 and 4.7 μg/m3 increase in the PM2.5- and PM2.5–10-averages of lag 2–5.ConclusionsWe observed positive but not statistically significant associations between prolonged exposures to UFP and respiratory mortality, which were independent of particle mass exposures. Further multi-centre studies are needed investigating several years to produce more precise estimates on health effects of UFP.  相似文献   

7.
Along with the rapid growth of economy in the postreform period after 1979,China has faced severe problems of resource overusing and environmental degradation which would threaten the sustainable development of economy and society.This article explores an effective mechanism of managing resource and environment in China.It examines some major resource and environmental issues,and constructs a framework of institution innovation to cover three sectors(government,market and society).In addition,the article analyzes their experience and evaluation in resource management and environmental conservation during the transitional period.We argue that the combination of market regulation,government intervention and public participation is an effective way of allocating resource and protecting environment.Some suggestions are put forward to balance the relationship between them,including coordinating role of government and market,building platform for market operation and creating an atmosphere of public participation.  相似文献   

8.
This paper quantifies a decomposition analysis of energy-related CO2 emissions in the industrial sectors of Shanghai over the period 1994-2007.The Log-Mean Divisia Index(LMDI) method is applied to this study in terms of six factors:labor force,labor mobility,gross labor productivity,energy intensity,fuel mix,and emission coefficient.In addition,the decoupling effect between industrial economic growth and CO2 emissions is analyzed to evaluate CO2 mitigation strategies for Shanghai.The results show that all labor productivity has the largest positive effect on CO2 emission changes in the industrial sectors,whereas labor mobility and energy intensity are the main components for decreasing CO2 emissions.Other factors have different effects on CO2 mitigation in different sub-periods.Although a relative decoupling of industrial CO2 emissions from the economic growth in Shanghai has been found,Shanghai should keep pace with the industrial CO2 emissions reduction by implementing low-carbon technology.These results have important policy implications:Plan C is the reasonable choice for Shanghai.  相似文献   

9.
10.
To evaluate the quantities of 137Cs from past nuclear tests being transported to and deposited in Japan by naturally-occurring phenomena, the authors developed long-range transport models for 137Cs considering Asian dust. The simulation using these models backed the observed recent increase of 137Cs deposition along the coast of the Sea of Japan in early spring. For the sake of public safety, it is vital to ascertain whether an increase of radioactive deposition is caused by natural phenomena or a nuclear accident. The observations in recent years have suggested that dust and soil containing 137Cs is transported from the regions around Inner Mongolia to Japan by the wind. In this paper, using observation data from the early spring of 2002 and 2006, the authors have found good agreement between the simulations and the measurements. The simulations reproduced the entrainment of 137Cs and subsequent transport to Japan caused by strong winds associated with low pressure areas around the Inner Mongolian grasslands. The most likely cause of high-level 137Cs deposition over northern Japan during March 2002 was 137Cs associated with particles transported at low-altitude (1 km) and subjected to precipitation on the 22nd to 24th.  相似文献   

11.
Full-scale technical potential provides a clear horizon for agricultural technology policy to meet the dual and urgent challenge of meeting food security and minimising the effects of climate change. A common stated goal is to double food production by 2050 to meet the needs of 9 billion people. The frontier of full-scale technical potential embodies this goal and provides a panacea for policy makers. However, the pathway between the present adoption of technologies towards this frontier is paved with some hazards which may be insurmountable. We develop a conceptual framework based on adoption levels of technology. The key criteria between current and potential adoption of technologies is the role of enablers, that is interventions which create changes in structural, distributional, technical, social and behavioural cultures. Policy must find optimal mixtures of regulation and voluntary mechanisms to fully encourage uptake of technologies and shift current adoption to meet full-scale technical potential. A range of technologies can be aligned with sustainable intensification and are examined in terms of this enabler framework. Further examination of the framework allows us to conclude that full-scale technical potential will never be achieved due to the stochastic nature of agricultural production, the diversity of motivations and institutional structures operating within food supply chains, as well as unbalanced cost-effectiveness criteria. We argue that sustainable intensification may provide a direction of travel for attaining food security but its poor conception, limited acceptability and understanding amongst the communities of interest lead to over-optimism in determining the journey to this final destination.  相似文献   

12.
Despite the adverse impact of the budget deficit in Hong Kong has been alleviated since the economic recovery from 2003, the fiscal deficit may return when there is another downturn in the economy if the problem is not handled fundamentally.Based on the economic and political situation from 1998 to 2003,the factors that lead to the budget deficit in Hong Kong are analyzed in four perspectives,including(a)increase in public expenditure;(b)decrease in public revenues;(c)poor management of public money and(d) weak administration.With a better understanding on these factors, possible solutions to the fiscal problem faced by the government may be developed.  相似文献   

13.
The goal of this work was to establish comparisons among environmental degradation in different areas from Southern Spain (Gulf of Cádiz) and Brazil (Santos and S?o Vicente estuary), by using principal component analyses (PCA) to integrate sediment toxicity (amphipods mortality) and chemical-physical data (Zn, Cd, Pb, Cu, Ni, Co, V, PCBs, PAHs concentrations, OC and fines contents). The results of PCA extraction of Spanish data showed that Bay of Cádiz, CA-1 did not present contamination or degradation; CA-2 exhibited contamination by PCBs, however it was not related to the amphipods mortality. Ría of Huelva was the most impacted site, showing contamination caused principally by hydrocarbons, in HV-1 and HV-2, but heavy metals were also important contaminants at HV-1, HV-2 and HV-3. Algeciras Bay was considered as not degraded in GR-3 and -4, but in GR-3' high contamination by PAHs was found. In the Brazilian area, the most degraded sediments were found in the stations situated at the inner parts of the estuary (SSV-2, SSV-3, and SSV-4), followed by SSV-6, which is close to the Submarine Sewage Outfall of Santos - SSOS. Sediments from SSV-1 and SSV-5 did not present chemical contamination, organic contamination or significant amphipod mortality. The results of this investigation showed that both countries present environmental degradation related to PAHs: in Spain, at Ría of Huelva and Gudarranque river's estuary areas; and in Brasil, in the internal portion of the Santos and S?o Vicente estuary. The same situation is found for heavy metals, since all of the identified metals are related to toxicity in the studied areas, with few exceptions (V for both Brazil and Spain, and Cd and Co for Brazilian areas). The contamination by PCBs is more serious for Santos and S?o Vicente estuary than for the investigated areas in Gulf of Cádiz, where such compound did not relate to the toxicity.  相似文献   

14.
Transuranics and fission products have been measured in lake sediment samples, collected in an alpine wetland, to determine their vertical distribution and calculate inventories. The radionuclides considered are 90Sr, 137Cs, 238Pu, 239/240Pu and 241Am. From the results, a better knowledge of radionuclide accumulation mode and behaviour was obtained. In addition, the origins of the individual pollutants could be deduced from activity ratios. Analyses were made on different sediment cores. The sampling sites were chosen to enable future determination of the mass balances of the radiopollutants. As the selected study area is in a recreational area used by urban populations, a rough estimate was made of the mean external dose from 137Cs for comparison with the French regulation.  相似文献   

15.
We used a stochastic production function method together with a farm-level dataset covering 18 farms over a 23-year period to assess the role that soil and water conservation practices play in affecting the climate change impacts on potato yield in northwestern New Brunswick, Canada. Our analysis accounted for the yield effects of farm inputs, farm technologies, farm-specific factors, seasonal climatic variables, soil and water conservation practices, and a series of interaction terms between soil and water conservation practices and climatic variables. Regression results were used in combination with three climate change scenarios developed by the Intergovernmental Panel on Climate Change (A2, A1B, B1) and four general circulation model predictions over three 30-year time periods (2011–2040, 2041–2070, and 2071–2100) to estimate a range of potato yield projections over these time periods. Results show that accounting for soil and water conservation practices in climate–yield relationships increased the impacts of climate change on potato yield, with yield increases of up to 38 % by the 2071–2100 period. These findings provide evidence that adoption of soil and water conservation practices can help boost potato production in a changing Canadian climate.  相似文献   

16.
A selection of PBDE congeners was analyzed in pooled blubber samples of pilot whale (Globicephala melas), ringed seal (Phoca hispida), minke whale (Balaenoptera acutorostrata), fin whale (Balaenoptera physalus), harbor porpoise (Phocoena phocoena), hooded seal (Cystophora cristata) and Atlantic white-sided dolphin (Lagenorhynchus acutus), covering a time period of more than 20 years (1986–2009). The analytes were extracted and cleaned-up using open column extraction and multi-layer silica gel column chromatography, and the analysis was performed on a GC-MS system operating in the NCI mode. The highest PBDE levels were found in the toothed whale species pilot whale and white-sided dolphin, and the lowest levels in fin whales and ringed seals. One-sided analyses of variance (ANOVA) followed by Tukey comparisons of means were applied to test for differences between years and sampling areas. Due to inter-year sampling variability, only general comparisons of PBDE concentrations between different sampling areas could be made. Differences in PBDE concentrations between three sampling periods, from 1986 to 2007, were evaluated in samples of pilot whales, ringed seals, white-sided dolphins and hooded seals. The highest PBDE levels were found in samples from the late 1990s or beginning of 2000, possibly reflecting the increase in the global production of technical PBDE mixtures in the 1990s. The levels of BDE #153 and #154 increased relative to the total PBDE concentration in some of the species in recent years, which may indicate an increased relative exposure to higher brominated congeners. In order to assess the effect of measures taken in legally binding international agreements, it is important to continuously monitor POPs such as PBDEs in sub-Arctic and Arctic environments.  相似文献   

17.
Global forest product value chains are increasingly subject to regulatory requirements, such as legality and sustainability certification. For African forest products, a shift in the export destinations of forest products towards China, the leading timber product manufacturer, has raised concerns that social and environmental product and process standards are declining. Aggregate drivers of this shift have been documented, yet there has been little enterprise-level analysis of Chinese actors in African timber imports based in China. This paper provides an initial analysis, highlighting implications for existing and emerging regulatory initiatives. Data show that although an increasing number of Chinese private enterprises is engaged in African timber imports, import volumes remain concentrated among a small number of geographically clustered private and state-owned firms. Government-led schemes are beginning to address timber legality concerns. But given China’s growing domestic market for finished wood products, sustainability certification requirements driven by the US and EU will not be sufficient to ensure improved sourcing by Chinese firms.  相似文献   

18.
Despite compelling reasons to involve nonscientists in the production of ecological knowledge, cultural and institutional factors often dis-incentivize engagement between scientists and nonscientists. This paper details our efforts to develop a biweekly newspaper column to increase communication between ecological scientists, social scientists, and the communities within which they work. Addressing community-generated topics and written by a collective of social and natural scientists, the column is meant to foster public dialog about socio-environmental issues and to lay the groundwork for the coproduction of environmental knowledge. Our collective approach to writing addresses some major barriers to public engagement by scientists, but the need to insert ourselves as intermediaries limits these gains. Overall, our efforts at environmental communication praxis have not generated significant public debate, but they have supported future coproduction by making scientists a more visible presence in the community and providing easy pathways for them to begin engaging the public. Finally, this research highlights an underappreciated barrier to public engagement: scientists are not merely disconnected from the public, but also connected in ways that may be functional for their research. Many field scientists, for example, seek out neutral and narrowly defined connections that permit research access but are largely incompatible with efforts to address controversial issues of environmental governance.  相似文献   

19.
This paper examines historical and future changes in normalised damages resulting from climate-related natural disasters for the Caribbean. Annualised damages of USD824 million are shown to be non-stationary over the historical period 1964 to 2013. Perturbations of (i) sea surface temperatures (SST) in the tropical North Atlantic (TNA) and (ii) the Atlantic multi-decadal oscillation (AMO) appear to be associated with historical damages. Both the TNA and AMO are known modulators of hurricane activity and rainfall amounts in the Caribbean. Indicative future damages are determined using (i) cumulative distribution functions (CDFs) of perturbed climate states and (ii) an artificial neural network (ANN) model of damages using projected TNA values and the state of the AMO derived from an ensemble of five coupled model intercomparison project phase 5 (CMIP5) global climate models (GCMs) run under the RCP 4.5 scenario. Estimates of future damages are determined when global mean surface temperatures (GMST) reach and exceed 1.5 °C above preindustrial levels. Annual normalised damages may potentially increase to at least USD1395 million or close to double for 1.5 °C. At 2 °C, higher damages may occur; however, large uncertainty across all GCMs prohibits the identification of significant difference between 1.5 and 2 °C. Significant differences in damages do, however, exist for at least two of the GCMs for the two climate states. The robustness of the results is discussed in light of a number of issues, including limitations associated with the data.  相似文献   

20.
Food traceability systems are capable of overcoming or alleviating problems caused by incomplete and asymmetric information on food markets.This study conducts an empirical analysis using 308 supermarket samples from China’s Beijing,Guangzhou,and Qingdao to determine the factors that influence supermarket behavior when operating traceability systems.The results show that operating profits(generated from food traceability systems),scale of operation,level of economic development(of a city),and government subsidies will positively affect the decision of supermarkets to use traceability systems.At the same time,government policies promoting food traceability systems should have a long-term role.  相似文献   

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