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The São Lourenço River (SLR) is used to supply potable waters for the cities of São Lourenço da Serra and Juquitiba, but receives the residues from the water treatment plants (WTPs) and sewage treatment plants (STPs), respectively. The purpose of this paper is to evaluate the impacts of the discharges of Juquitiba’s WTP and STP on the quality of the SLR, by using an integrated approach based on different lines of evidence.

Six sampling sites were established along the river and comprised areas situated upstream and downstream of the discharges. Five sampling surveys were performed between 2004 and 2006 for collecting water and sediment samples for ecotoxicological assays. In two of these campaigns, benthic community structure and geochemistry (metals, nutrients and sediment texture) were also assessed.

Concentrations of P, Fe and Al in waters exceeded the national standards, but sediments were not considered to be contaminated by metals or nutrients. Water and sediments tended to exhibit marginal toxicities, excluding the sediments from JQT007 and JQT008 that were frequently toxic. Combination of geochemistry, toxicity and ecological indices indicated that some sites are not degraded, but in some stations the benthic alteration may be due to non-measured contaminants, especially in JQT007 and JQT008.

As the use of waters from SLR for public supply has increased, these results show that action should be taken in order to reverse the environmental degradation of SRL.

This research combined sediment and water quality assessments in order to provide a more suitable and reliable diagnostic of the environmental quality of the SLR.

This paper aims to elucidate the geochemical characteristics of the hydrothermally altered rocks with gold mineralization and the elemental transfers in hydrothermal alteration hosted in alkaline complex in Hongshan area, Taihang Orogen, North China, and preliminarily discuss the relationship between the gold mineralization and the hydrothermal alteration.

Based on detailed field investigation, sampling and petrographical observation, major oxides and trace elements of nine rock samples are analyzed, and the method of mass balance equation is used in calculation of the elemental transfer.

Three alteration stages in the Hongshan area are identified, which are the early, main and late alterations. The early one is characteristic of extensive pyritization in the complex, which is related to the mantle-derived magmas and occurs before gold mineralization. The main one is characterized by developing a great deal of altered rock in fracture zones with the gain of many elements and the loss of a few elements. The late one is dominated by limonitization, that is limonite replacing the early pyrite or Fe₂O₃ replacing FeO in rocks. In the main alteration, the altered rocks obviously gain fluid component (LOI, i.e. loss on ignition) and elements such as V, As, Rb, Au, La, Ce and Nd and total rare earth elements (REEs). Elements such as K, Fe, Cu, Zn, Y, Mo, Sb, W, Re and U are gained in some altered rocks. Na and Sr are lost in all altered rocks, and Th and Bi are lost in some ones in the meantime. The following elements: Si, Mg, Mn, Ca, Li, Sc, Cr, Co, Ni, Zr, Ag, Ba and Hg show either gain or loss in different altered rocks. Au is notably enriched in the hydrothermal alteration. The elemental gain or loss in the altered rocks indicates that the main mineralization develops extensive de-alkalinization, local potassic metasomatism, silicification or desilicification.

Although there have been extensive studies on the hydrological and erosional impacts of logging, relatively little is known about the impacts of conversion into agricultural plantation (namely rubber and oil palm). Furthermore, studies on morphological impacts, sediment-bound chemistry and forensic attribution of deposited sediment to their respective sources are scarcer. This chapter introduces the potential for using the multi-proxy sediment fingerprinting technique in this context. Featuring pilot projects in two major flood-prone river systems in Malaysia, the studies explore application of geochemistry-based sediment source ascription. The geochemical signatures of sediment mixtures on floodplains were compared to sediments from upstream source tributaries. The tributaries were hypothesised to have different geochemical signatures in response to dominant land management. The first case study took place in the Segama River system (4,023 km²) of Sabah, Malaysian Borneo where a mixture of primary forest, logged-forests and oil palm plantations were predominant. The second case study was in the Kelantan River Basin (13,100 km²) with two major tributaries (Galas River and Lebir River) where logged-forests and rubber and oil palm plantations are dominant land-uses. Both case studies demonstrated the applicability of this method in ascribing floodplain deposited sediment to their respective upstream sources. Preliminary results showed that trace elements associated with fertilisers (e.g. copper and vanadium) contribute to agricultural catchment signatures. Alkaline and alkaline-earth elements were linked to recently established oil palm plantations due to soil turnover. Mixing model outputs showed that contributions from smaller, more severely disturbed catchment are higher than those from larger but milder disturbed catchments. This method capitalises on flood events to counter its adverse impacts by identifying high-priority sediment source areas for efficient and effective management.

A detailed analytical study of Leping bark liptobiolith in Jiangxi was conducted to determine its petrographic characteristics and depositional environment based on coal petrography and geochemistry. Results indicate that barkinite mainly occurs in the middle and lower coal sea4ms, whereas less barkinite and more vitrinite occur in the middle and upper coal seams. Coal facies analysis of bark liptobiolith was performed to determine its characteristics under various depositional conditions, such as the presence of a water table and gelification during coal formation. Results indicate that the environmental evolution of bark liptobiolith begins from brackish-marine swamp facies (barkinite-rich coal seam) and ends in back barrier swamp facies (barkinite-poor coal seam).

This paper aims to examine the geochemical change experienced by laterites in Kerala, India, subjected to tropical monsoonal climate. These sediments are underlain by hard rock. The source rock characteristics have a major stake on the ultimate composition of sediments, as also the climatic conditions which an area experience.

Core samples have been obtained from several locations in a lateritic plateau. The upper portions of the borehole cores are composed of the lateritic hard cap, followed by lateritic soils. The soil samples were subjected to sediment texture analysis and XRF analysis (Bruker S4 Pioneer Sequential Wavelength-Dispersive XRF) for the determination of major elements ((in oxide form).

Major element geochemistry has revealed the following order of relative proportions of elements (in oxide form) SiO₂ > Al₂O₃ > Fe₂O₃ > TiO₂ >> Na₂O > P₂O₅ > CaO > K₂O > MgO > MnO. Even though the concentrations of SiO₂, Al₂O₃ and Fe₂O₃ contribute 90% of major element chemistry, there is no significant correlation found for these elements within themselves or with others.

Microscale movement of elements could not be characterised in this study. This requires access to an electron probe micro analyzer.

The practical implication of tropical weathering is that enhanced chemical leaching leads to movement of most elements out of the system, except for Al, leading to the possible formation of bauxite, or aluminous laterite.

The weathered products in this study provide livelihood sustenance for many of the local households, through manual production of laterite bricks, which are used in construction.

The indices of the intensity of chemical alteration/weathering like chemical index of alteration (CIA), chemical index of weathering (CIW) and weathering index of parker (WIP) reveal that the sediments indicate intense weathering of the source area prior to being deposited in the present location. This indicates enhanced monsoonal activity in the provenance areas, than that obtained today.

The purpose of this paper is to discuss a novel life cycle approach to education for sustainable development (ESD) where the students become “design thinkers”.

A case study on the creation, development and utilisation of educational games by university students is presented. The paper discusses the case study in the context of Kolb’s experiential learning and dynamic matching model, Perry’s stages of intellectual development and Beech and Macintosh’s processual learning model. The data used were from questionnaire feedback from the pupils who played the games and students who designed the games. Further qualitative feedback was collected from local schools involved in playing the games created by the students.

Overall, the students responded positively to the assessment and would like to see more of this type of assessment. They enjoyed the creativity involved and the process of developing the games. For the majority of the skill sets measured, most students found that their skills improved slightly. Many students felt that they had learnt a lot about effectively communicating science. The school children involved in playing the student-created games found them accessible with variable degrees of effectiveness as engaging learning tools dependent on the game.

This paper contributes a new approach to ESD which incorporates learner-centred arrangements within a full life cycle of game creation, delivery, playing and back to creation. The games can be used as a tool for enhancing knowledge and influencing behaviours in school children whilst enhancing ESD capacity in schools. The assessment also helps forge important links between the academic and local communities to enhance sustainable development.

It is shown in natural gas proportion mixing experiments that a mixed-source natural gas is the physical combination of end member gas. Both the carbon and hydrogen isotopes in the mixed-source natural gas can be expressed by the weighted average of corresponding components content and isotopes of end member gas. Under certain geological setting, the selection of end member gas is the key to mixed-source ratio calculation. Then, it's better to estimate the mixed-source ratio with δ¹³C₁ and component data according to the weighted average calculation formula. The analysis on natural gas geochemistry characteristics show that the natural gas extracted from Jingbian Gas Field in the Ordos Basin is mainly an upper Paleozoic coal-derived gas. In the analysis of geological conditions for reservoir forming and characteristics of natural gas, natural gas from Longtan 1 Well and Tao 6 Well were selected as the end member gases of lower Paleozoic oil-type gas and upper Paleozoic coal-type gas respectively to calculate the mixed-source ratio of natural gas in Jingbian Gas Field. The ratio of upper Paleozoic coal-derived gas mostly accounts for over 70% and its average ratio reaches 81%. Therefore, the exploration of natural gas of Ordos Basin should be focused on the upper palaeozoic coal source rock, and attention should be paid to the matching of coal source rock in the exploration of weathered crust gas deposit.

Traditional ceramic industries (ceramic tiles, frits, glazes and pigments) generate solid wastes, wastewater and gas emissions that have different characteristics depending on the type of product made. The present study was undertaken to define a series of test methodologies for characterising each type of waste. The approach involved defining the elements to be analysed in each kind of sample, subsequently carrying out the respective test methods for the determinations in terms of type of parameter and sample. In gas emissions, the study addressed fluorine compound analysis. In liquid samples, AAS and ICP‐OES techniques were compared, validating the methods by using reference materials and participating in CALITAX and AQUACHECK intercomparison rounds on wastewater analysis. In solid samples, ICP‐OES and XRF techniques were compared, validating the methods by participating in International Proficiency Tests of Analytical Geochemistry Laboratories (GEOPT‐7, GEOPT‐8 and GEOPT‐9). The selective electrode determination of fluorine in gas emissions yields good results. The study shows that toxicity can be determined in liquid and solid samples by the bioluminescence assay. In liquid samples, good results were found for metal elements analysis by AAS and ICP‐OES, the latter being better. Finally, in solid wastes the ICP‐OES technique has advantages in analysing minor elements compared with XRF, whereas XRF is more suitable for analysing major elements, as it is a faster, more reproducible technique.

The purpose of this paper is to examine the practice potential of self-administered drop-off as a survey mode for contingent valuation (CV) studies.

This paper conducts an empirical comparison of mode effects of two survey methods for improved ecological services in Beijing. Data were collected from a CV survey, which has two subsamples, one using face-to-face interviews and the other employing self-administered drop-off surveys.

There is some evidence of social desirability bias in the face-to-face interviews for the participation question; however, such effects do not carry over to subjects’ responses to the contribution decision. No difference is observed in sample demographics between modes. And satisficing effect is not observed in the drop-off survey in this study.

More well-controlled mode comparisons are warranted to test the robustness of the results; and collection time effects as well as the use of drop-off surveys for environmental valuation with different levels of complexity and familiarity are worthy of further study.

The authors find more similarities between drop-off and face-to-face surveys than differences therefore support the practice of self-administered drop-off surveys in CVM for environmental valuation.

This paper adds to the limited number of well-controlled mode comparisons in the CV surveys, and contributes to a better understanding of self-administered drop-off surveys, a potential low-cost alternative to face-to-face interviews in future CV applications.

We present the finite element simulations of reactive mineral‐carrying fluids mixing and mineralization in pore‐fluid saturated hydrothermal/sedimentary basins. In particular we explore the mixing of reactive sulfide and sulfate fluids and the relevant patterns of mineralization for lead, zinc and iron minerals in the regime of temperature‐gradient‐driven convective flow. Since the mineralization and ore body formation may last quite a long period of time in a hydrothermal basin, it is commonly assumed that, in the geochemistry, the solutions of minerals are in an equilibrium state or near an equilibrium state. Therefore, the mineralization rate of a particular kind of mineral can be expressed as the product of the pore‐fluid velocity and the equilibrium concentration of this particular kind of mineral. Using the present mineralization rate of a mineral, the potential of the modern mineralization theory is illustrated by means of finite element studies related to reactive mineral‐carrying fluids mixing problems in materially homogeneous and inhomogeneous porous rock basins.