攀枝花市大气污染物降水清除机制的研究

本文采用了主成份分析及因子分析的方法,研究了影响降水pH值的主要源及其贡献和这些源被降水清除的机制。分析结果表明:大气中一次污染物是影响降水pH及各种成分浓度的主要因素。人为污染源包括高排放源、低排放源和汽车源,它们的排放物以碱性物质为主;自然污染源包括输送物、腐烂物、自然NOx等,它们的排放物主要是酸性物质;在一般情况下,降水的pH值取决于高、低排放源排放的碱性物质的多寡;降水量越大,清除的污染物越多,在雨季各测点降水平均pH值为6.31～7.10。在高排放源影响小的地方,对持续时间长的大雨,降水后期的pH能反映自然源的影响,其值小于5.60。可见,攀枝花市酸雨几率极低甚至降水呈碱性,     

Assessing cause and effect of multiple stressors on marine systems

An operational framework is developed to serve as a guideline for investigating causal relationships between environmental stressors and effects on marine biota. Because of the complexity and variability of many marine systems, multiple lines of evidence are needed to understand relationships between stressors and effects on marine resources. Within this framework, a weight of evidence approach based on multiple lines of evidence are developed and applied in a sequential manner by (1) characterizing the study system which involves determining if target biota are impaired, assessment of food and habitat availability, and measuring contaminant levels in the environment, (2) assessing direct effects of contaminant exposure on target biota using biomarkers and assessing indirect effects of exposure using suites of bioindicators, and (3) applying standard causal criteria based on epidemiological principles and diagnostic health profiling techniques to assess potential causes. Use of multiple lines of evidence should also reduce the risk of false positives (Type I error or falsely concluding that there is a causal relationship when there is none) and false negatives (Type II error or falsely concluding there is not a causal relationship when there actually is). Understanding causal relationships and the mechanistic processes between environmental stressors and effects on biota is important in the effective management and restoration of impaired marine ecosystems.     

Impact of quarrying gypsum in a semidesert karstic area (Sorbas,SE Spain)

The Messinian gypsum of Sorbas is intensively karstified, with hundreds of dolines and numerous, highly unusual exo- and endokarstic forms. Amongst these the tumuli are especially spectacular, as are the large caverns, adorned with numerous speleothems, some of which have not been described anywhere else in the World. The extraction of the gypsum has impacted practically all the elements of the environment (landscape, water, soil, subsoil, flora, fauna, etc.) and, in particular, all of the karstic forms. In addition to endangering the caves and the natural treasures that they contain, it affects the surface waters, markedly modifying the hydrographic network. Groundwaters, which now occur in the bottom of a quarry, are also affected.     

Environmental impact of drainage of Dianzi Iron Mine on the groundwater system of the Dawu Water Supply Base

Due to growing water extraction for industry and agriculture, the Dawu Water Supply Base, in the east of Zibo, China, has been in a state of serious over-extraction. It will also be affected by the deep drainage of the Dianzi Iron Mine, which will be exploited in 2005. As to the environmental impact on the groundwater system of the Dawu Water Supply Base is concerned, this paper makes a systematic study about the influence of the mine draining on the water-supply environment of the Dawu Water Supply Base by using the numerical model of groundwater system. The result shows that the groundwater level will have an additional drawdown of 1.2–1.8 m/yr by the mine draining alone. The numerical analysis results indicate that the optimal model for determining the best extraction plan is the solution for the contradiction between water supply and water drainage.     

Morphotectonic evaluation of the Delhi region in northern India,and its significance in environmental management

This paper deals with the morphotectonic evaluation of the Delhi region in northern India to understand its impact on land use and urban development. To accommodate heavy urbanization and population rise (being the capital of India), the area has undergone tremendous environmental degradation resulting from a mismatch between adopted land use and morphotectonic considerations. The geomorphic and drainage signatures of the region have evolved out of interaction of varied geological parameters including neotectonic activities. We have evaluated the changes in the drainage pattern of the Yamuna River in the Delhi region to underline its significance in geomorphic evolution and subsequent land use and/or land suitability. The Yamuna River has shown variations both in channel position and geometry over the last two centuries. The observed migration pattern of the river (shifting of confluences, position and disposition of palaeochannels, etc.,) cannot be attributed to normal river phenomenon and appears to have been effected by neotectonic changes. In addition, some case studies are discussed to underline the significance of geomorphic factors in urban development.     

Cartographic techniques for mapping the geochemical data of stream sediments: the “Sample Catchment Basin” approach

The Sample Catchment Basin (SCB) mapping technique extends the representativeness of the geochemical features of stream sediments to the surface of the whole upstream drainage basin. SCB boundaries clash with the water divides traced from each sampling point and are limited upstream by the presence of further SCBs. They are also assumed to represent the elementary map unit. The rank of SCBs can be defined counting the number of upstream SCBs along the branches of a fluvial network. The presence of low rank SCBs minimizes the statistical redundancy of measures. The SCB technique is particularly suitable for the geochemical mapping of mountainous or hilly areas and to correctly display the information into a morphological context. This approach can be also valuable in the case of low sampling density, inhomogeneous sampling schemes, and especially when very accurate evaluations of the spatial distribution of chemicals (with natural or anthropogenic origin) are required.     

Geochemistry of beryllium in Bulgarian coals

The beryllium content of about 3000 samples (coal, coaly shales, partings, coal lithotypes, and isolated coalified woods) from 16 Bulgarian coal deposits was determined by atomic emission spectrography. Mean Be concentrations in coal show great variability: from 0.9 to 35 ppm for the deposits studied. There was no clear-cut relationship between Be content and rank. The following mean and confidence interval Be values were measured: lignites, 2.6 ± 0.8 ppm; sub-bituminous coals, 8.2 ± 3.3 ppm; bituminous coals, 3.0 ± 1.2 ppm; and anthracites, 19 ± 9.0 ppm. The Be contents in coal and coaly shales for all deposits correlated positively suggesting a common source of the element. Many samples of the coal lithotypes vitrain and xylain proved to be richer in Be than the hosting whole coal samples as compared on ash basis. Up to tenfold increase in Be levels was routinely recorded in fusain. The ash of all isolated coalified woods was found to contain 1.1 to 50 times higher Be content relative to its global median value for coal inclusions.Indirect evidence shows that Be occurs in both organic and inorganic forms. Beryllium is predominantly organically bound in deposits with enhanced Be content, whereas the inorganic form prevails in deposits whose Be concentration approximates Clarke values.The enrichment in Be exceeding the coal Clarke value 2.4 to 14.5 times in some of the Bulgarian deposits is attributed to subsynchronous at the time of coal deposition hydrothermal and volcanic activity.     

After the 1997 financial crisis in Bangkok: The behaviour and implications of a new cohort of street vendors

After the 1997 financial crisis, many retrenched workers preferred not to return to provincial homes but remained in Bangkok to establish informal retail businesses in branded and other consumer products. In contrast to traditional street vendors, who specialized in food items primarily catering for low‐income customers, and focused on high volume, these ‘new generation’ street vendors also adopted more formal business practices. Given their greater sophistication and better education, we hypothesized that they would be more organized advocates of vendors' rights and thus more prone to conflicts with municipal authorities. Based on interviews, however, we found that new generation vendors are adaptive to location and business strategy, and prefer a low profile in dealing with officialdom. By contrast, traditional vendors remained more tied to particular spaces, are more likely to stand up for their rights to use public space and, because they expect more from government, are more prone to conflicts with municipal authorities. Our findings relate to ongoing discussion on the rights and needs of street vendors to access urban public space and the responsibilities of authorities to meet and provide for these informal sector livelihoods that make up a significant share of the national economy in Thailand, as elsewhere in the global South.     

Growing up and cleaning up: The environmental Kuznets curve redux

Borrowing from the Kuznets curve literature, researchers have coined the term “environmental Kuznets curve” or EKC to characterize the relationship between pollution levels and income: pollution levels will increase with income but some threshold of income will eventually be reached, beyond which pollution levels will decrease. The link between the original Kuznets curve, which posited a similar relationship between income and inequality, and its pollution-concerned offspring lies primarily with the shape of both curves (an upside-down U) and the central role played by income change. Although the EKC literature has burgeoned over the past several years, few concrete conclusions have been drawn, the main themes of the literature have remained constant, and no consensus has been reached regarding the existence of an environmental Kuznets curve. EKC research has used a variety of types of data and a range of geographical units to examine the effects of income levels on pollution. Changes in pollution levels might also be at least partly explained by countries’ position in the demographic transition and their general population structure, however little research has included this important aspect in the analysis. In addition, few analyses confine themselves to an evaluation for one country of the long-term relationship between income and pollution. Using United States CO₂ emissions as well as demographic, employment, trade and energy price data, this paper seeks to highlight the potential impact of population and economic structure in explaining the relationship between income and pollution levels.     

A conceptual framework for analysing adaptive capacity and multi-level learning processes in resource governance regimes

Governance failures are at the origin of many resource management problems. In particular climate change and the concomitant increase of extreme weather events has exposed the inability of current governance regimes to deal with present and future challenges. Still our knowledge about resource governance regimes and how they change is quite limited. This paper develops a conceptual framework addressing the dynamics and adaptive capacity of resource governance regimes as multi-level learning processes. The influence of formal and informal institutions, the role of state and non-state actors, the nature of multi-level interactions and the relative importance of bureaucratic hierarchies, markets and networks are identified as major structural characteristics of governance regimes. Change is conceptualized as social and societal learning that proceeds in a stepwise fashion moving from single to double to triple loop learning. Informal networks are considered to play a crucial role in such learning processes. The framework supports flexible and context sensitive analysis without being case study specific.First empirical evidence from water governance supports the assumptions made on the dynamics of governance regimes and the usefulness of the chosen approach. More complex and diverse governance regimes have a higher adaptive capacity. However, it is still an open question how to overcome the state of single-loop learning that seem to characterize many attempts to adapt to climate change. Only further development and application of shared conceptual frameworks taking into account the real complexity of governance regimes can generate the knowledge base needed to advance current understanding to a state that allows giving meaningful policy advice.