Evaluation of the Impact of Acid Mine Drainage on the Chemistry and the Macrobenthos in the Carolina Stream (San Luis – Argentina)

The purpose of this study was to evaluate the impact of acid mine drainage on the chemistry and the macrobenthos of the Carolina stream (San Luis – Argentina). Samples were obtained in the years 1997–1998 at two sites: site C₁, located 200 m upstream of the drainage, and site C₂, located 800 m downstream. The system buffer capacity was evaluated in the non – contaminated site by means of the buffer index calculation. The physico – chemical changes observed as a consequence of the contribution of acid mine drainage (AMD) were: a decreasing of pH and an increase in the ionic concentration, especially sulfate and Fe coming from the oxidation produced by chemiolithotrophic bacteria. The values obtained indicated a low buffer capacity and a high intrinsic vulnerability of the system to resist the impact originated by the AMD, producing a remarkable decreasing of pH of the receiving stream. These changes caused modifications in the original benthic community that was replaced by organisms more tolerant to the acid stress. A reduction in the abundance and in the taxonomic richness of the benthic macroinvertebrates was observed when compared with the reference station. An increase in the proportion of Chironomidae and of Acari and a decrease in the proportion of the remaining taxa were observed. The most sensitive groups were Ephemeroptera, Trichoptera and Mollusca. The community was mostly affected by the following variables: pH, conductivity, sulfate and dissolved total Fe.     

Health Survey Among People Living Near an Abandoned Mine. A Case Study: Jales Mine, Portugal

Campo de Jales is a village surrounding the abandoned Jales mine. The area is heavily contaminated with heavy metals and dusts from large tailings piles as result of centuries of mining operations. The aim of this study is to investigate potential health threats associated with site contamination. The population studied comprised two groups: people living in Campo de Jales (n = 229) and a control group – people living in Vilar de Macada (n = 234). Lead and cadmium exposure and symptoms survey were carried out.The results showed a significant higher levels of blood lead and cadmium between the Campo de Jales residents (lead: 9.5 microgr/dl versus 7.7 microgr/dl; cadmium: 0.84 microgr/dl versus 0,65 microgr/dl) as well as to a higher prevalence of respiratory and irritation symptoms and great concern about his own health.In conclusion: community is the scene of long-term health problems resulting from the site environmental contamination.     

Phenotypic plasticity in a mutualistic association between the sponge Haliclona caerulea and the calcareous macroalga Jania adherens induced by transplanting experiments. I: morphological responses of the sponge

The mutualistic association between the sponge Haliclona caerulea and the calcareous red macroalga Jania adherens is conspicuous on shallow rocky regions of Mazatlán Bay (eastern tropical Pacific, Mexico). Transplanting experiments were carried out to examine the morphological responses of the association to an environmental depth gradient. Simultaneously, we conducted caging experiments to examine the effects of predation (mainly by angelfishes) on association morphology. For this, we transplanted specimens of the association from a control area at 3 m depth to depths of 1 and 5 m, and measured the morphological responses in the association (macro- and microstructure) from the three sites before and after 103 days. The association had the capacity to adjust both macro and micromorphologically, and both external morphology and body structure changed significantly with depth. The specimens grown at 1 m developed a larger surface area of attachment, higher organic density and higher inorganic content than the control specimens at 3 m, and the organisms grown at 5 m depth. We also detected significant differences in the aquiferous system of the sponge, which developed smaller and more numerous oscula at 1 m than at 5 m depth. These differences seem to be consistent with the wave movement as one of the main regulatory factors of the morphology of the association. However, the spicules from H. caerulea were most slender in shallow water, which is not consistent with increasing robustness in the face of greater wave force. The algal skeleton supplied up to 27% of the total inorganic structure of the association; thus, algal contribution significantly reduces the energy costs of spicule production, specifically under high wave exposure, when H. caerulea requires structural reinforcement relative to organic content. The contribution of the sponge to the association (as ratio Si to CaCO₃) increased significantly from 3 to 5 m (12% in the uncaged specimens and 22% in the caged specimens), showing that the mutualistic relationship decreases with depth. The production of sponge branches in caged individuals was the most notable difference from uncaged morphs, which could suggest the effect of predators like angelfishes. However, branches could also be a response to the reduction in water movement and irradiance inside the cages. Sponges are known to show morphological acclimation in response to habitat variation, but this is the first study to show it in a sponge living in association with a macroalga.     

Sonophotocatalytic degradation of alazine and gesaprim commercial herbicides in TiO2 slurry

The photocatalytic degradation of alazine and gesaprim commercial herbicides was carried out in aqueous TiO(2) suspensions under UV light (15W, 352 nm). Degradation of these herbicides was also observed by the combined effects of photocatalysis with sonolysis (sonophotocatalysis) using an ultrasound source of 20kHz. Degradation profiles were recorded by measuring the concentration of the active compounds present in the alazine (alachlor and atrazine) and gesaprim (atrazine) by HPLC as a function of irradiation time (sound and/or light). Over 90% of the active component in the gesaprim was abated and those in alazine were completely degraded. The content of total organic carbon and chemical oxygen demand was also monitored. Mineralization of the commercial herbicides was achieved. Over 80% of chemical oxygen demand abatement was attained for both herbicides with sonophotocatalysis at 150 min of irradiation time. The photocatalytic degradation of the herbicides followed a pseudo-first order kinetics and their rate constant was increased by the combined effects of sonolysis.     

Impact of three interactive Texas state regulatory programs to decrease ambient air toxic levels

The Federal Clean Air Act (FCAA) framework envisions a federal-state partnership whereby the development of regulations may be at the federal level or state level with federal oversight. The U.S. Environmental Protection Agency (EPA) establishes National Ambient Air Quality Standards to describe “safe” ambient levels of criteria pollutants. For air toxics, the EPA establishes control technology standards for the 187 listed hazardous air pollutants (HAPs) but does not establish ambient standards for HAPs or other air toxics. Thus, states must ensure that ambient concentrations are not at harmful levels. The Texas Clean Air Act authorizes the Texas Commission on Environmental Quality (TCEQ), the Texas state environmental agency, to control air pollution and protect public health and welfare. The TCEQ employs three interactive programs to ensure that concentrations of air toxics do not exceed levels of potential health concern (LOCs): air permitting, ambient air monitoring, and the Air Pollutant Watch List (APWL). Comprehensive air permit reviews involve the application of best available control technology for new and modified equipment and ensure that permits protect public health and welfare. Protectiveness may be demonstrated by a number of means, including a demonstration that the predicted ground-level concentrations for the permitted emissions, evaluated on a case-by-case and chemical-by-chemical basis, do not cause or contribute to a LOC. The TCEQ's ambient air monitoring program is extensive and provides data to help assess the potential for adverse effects from all operational equipment in an area. If air toxics are persistently monitored at a LOC, an APWL area is established. The purpose of the APWL is to reduce ambient air toxic concentrations below LOCs by focusing TCEQ resources and heightening awareness. This paper will discuss examples of decreases in air toxic levels in Houston and Corpus Christi, Texas, resulting from the interactive nature of these programs.

Implications: Texas recognized through the collection of ambient monitoring data that additional measures beyond federal regulations must be taken to ensure that public health is protected. Texas integrates comprehensive air permitting, extensive ambient air monitoring, and the Air Pollutant Watch List (APWL) to protect the public from hazardous air toxics. Texas issues air permits that are protective of public health and also assesses ambient air to verify that concentrations remain below levels of concern in heavily industrialized areas. Texas developed the APWL to improve air quality in those areas where monitoring indicates a potential concern. This paper illustrates how Texas engaged its three interactive programs to successfully address elevated air toxic levels in Houston and Corpus Christi.     

All Fish for China?

In this paper we examine the effect of Gross Domestic Product (GDP) on the level of fish intake in China in comparison with the rest of the world. We also analyse the origin and destination of China’s seafood products in order to understand the main patterns during the last decades. The results show that in the 1961–2011 period the rate of growth of the GDP in China doubled that of other developing regions, while the daily fish intake of China increased fourfold, making China the largest fish consumer in the world. Given the size and scale of China’s role in production, consumption, and global transformation of seafood markets, China is shaping a new era of industrialization in the history of the fishing industry.     

Influence of the operation conditions on CO2 capture by CaO-derived sorbents prepared from synthetic CaCO3

In this work, a statistical experimental design is performed in order to prepare CaCO₃ materials for use as CaO-based CO₂ sorbent precursors. The influence of different operational parameters such as synthesis temperature (ST), stirring rate (SR) and surfactant percent (SP) on CO₂ capture is studied by applying Response Surface Methodology (RSM). The samples were characterized using different analytical techniques including X-ray diffraction, N₂ adsorption isotherm analysis and Scanning Electron Microscopy–X-ray Energy Dispersive Spectroscopy (SEM-EDX). CO₂ capture capacity was determined by means of a thermogravimetric analyzer which recorded the mass uptake of the samples when these were exposed to a gas stream containing diluted (15%) CO₂. The statistical approach used in this work provides a rapid way of predicting and optimizing the main preparation variables of CaO-derived sorbents for CO₂ sorption. The results obtained clearly indicate that four parameters statistically influence CO₂ uptake: SR, the square of SR, its interaction with SP and the square of SP.     

A critical discussion of research on the social acceptance of renewable energy generation and associated infrastructures and an agenda for the future

Social sciences’ research on the social acceptance of renewable energy generation and associated technologies (RET), such as high voltage power lines, has been growing in the last decades. In fact, while RET are considered one of the main mitigation measures of climate change, opposition to their construction, and namely from the local communities living nearby, is often found. Important conceptual proposals have been made for a better understanding of opposition, however, this literature still presents some limitations. Here, I will discuss two of them: first, the main focus on the local and, with it, the lack of a relational and critical approach, which recognizes opposition and other types of responses to RET as public participation in RET-related issues; second, the focus on the individual and the consequent lack of examining people’s material practices and engagements.     

Empowering communities – the role of intermediary organisations in community renewable energy projects in Indonesia

Community Renewable Energy (CRE) has been defying conventional energy systems for decades, though only recently it started to feature in academic and institutional discourses. Despite its new appeal, the literature on the impacts and factors influencing CRE projects is still scarce and builds mostly on studies in Europe and North America. In developing countries, where electricity access is low and energy poverty is prevalent, CRE can offer interesting opportunities for rural electrification and added benefits. The objective of this study is to assess the impacts of community-owned renewable energy projects and identify the internal and external drivers and barriers to their success. An exploratory case-study approach was used for collecting data, through interviews and observations, in two community micro-hydro projects in Indonesia. The results showed positive socio-economic impacts that exceed electrification benefits, and the reported success of community energy projects can be traced back to a combination of community-level as well as external factors. Yet, particularly important is the role of the intermediary organisation (Ibeka) in building communities’ ownership, enhancing (technical, entrepreneurial and managerial) capacities, transferring knowledge and technology, establishing innovative financing models and shaping policy. Such organisations are critical in bridging external and internal factors and thus represent a key element in integrating the proposed analytical frameworks.