Pristine aquatic systems in a Long Term Ecological Research (LTER) site of the Brazilian Cerrado

The maintenance of limnological monitoring programs in the Cerrado Domain is crucial as a provision of useful information about temporal variations in land use and their respective water quality responses, considering its importance as water source for different Brazilian hydrographic basins. The purpose of this research was to describe limnological variables of low-order lotic systems located in the Cerrado Long Term Ecological Research (LTER) site (Environmental Protection Area (APA) Gama and Cabeça de Veado, Federal District of Brazil). Altogether, nine different streams were considered in this study. Samplings were conducted between 2010 and 2012, concentrated in the dry and rainy seasons. The sampling sites were generally characterized by low nutrient concentrations (e.g., medians, TP?=?14.8 μg L^?1, TN?=?20.0 μg L^?1, NO₃?=?13.8 μg L^?1) and slightly acidic waters (median, pH?=?5.3), with quite low electrical conductivity values (median?=?6.4 μS cm^?1). However, water quality degradation as a response to diffuse pollution was reported in some sampling points (e.g., Onça and Gama streams), expressed by relatively higher N and P concentrations, which were probably highlighted by the good water quality of the data set as whole. Although there was a trend to higher values of nitrogen forms during the dry season, significant statistical differences between the seasonal periods were reported only for the variables temperature and dissolved silica, which were higher in the dry and rainy season, respectively. The streams located in the preserved areas inside the ecological stations of APA Gama and Cabeça de Veado can still be considered good examples of reference lotic systems in the Cerrado Domain; notwithstanding, this study reported incipient signs of water quality degradation which cannot be overlooked in future limnological monitoring.     

Integration of ozonation and an anaerobic expanded granular sludge bed reactor for micropollutant removal from sewage

Environmental Science and Pollution Research - Conventional sewage treatment systems are generally not designed to remove micropollutants, requiring the development of new technologies, such as the...     

Site-Specific Characterization of Castromil Brownfield Area Related to Gold Mining Activities

Castromil is one of the gold mining areas in Portugal that has been abandoned since 1940. This area, which was first mined in Roman times, is located within a Hercynian granite body near the contact with Silurian metasediments. Gold is essentially disseminated along veins in the silicified granite, running NW-SE, related with a shear zone and frequently associated with sulphides (arsenopyrite and basically pyrite). In paragenetic terms, three stages of mineralization are considered: ferro-arseniferous (quartz + arsenopyrite I + pyrite I + pyrrhotite + bismuth), zinciferous (sphalerite + chalcopyrite), and remobilization (arsenopyrite II + galena + gold). Due to the lack of laws and environmental education, Castromil is today a gold mining heritage site where we can detect the consequences of an incautious exploration (tailings, wells and adits located in the old explored zone) and where a residential area is located. In order to characterize the actual state of the old mining area the trace metal contamination of soils and waters by mining activities was investigated. In the studied area 106 soil samples, 15 waters and 20 plants were sampled and analysed. The soil samples were analysed for 32 elements by ICP-AES. Waters were analysed by ionic chromatography and ICP-MS for major and trace elements. Plants were analysed for As, Fe and Pb by AAS. The results are discussed taking into account the risk-based standards for soils and groundwater's (target and intervention values) proposed by Swartjes (1999). The results show elevated concentration of As and Pb which were found in soils collected from agricultural areas. Foodstuff plants species collected in the Castromil agricultural area show high concentrations of As in the leaves (cabbage and lettuce) and in the tubers (potatoes). Groundwaters in the mining area contain high concentrations of As that exceeds the intervention values. The area must to be subject to a remediation process, considering the actual risks to humans and ecosystems and the risks due to contaminant migration.     

Effect of alum addition on the performance of submerged membranes for wastewater treatment.

The effect of aluminum sulfate (alum) addition on membrane performance was investigated, with a particular focus on membrane fouling. During initial operation, alum was added and the performance monitored. After terminating alum addition, the transmembrane pressure (TMP), which is indicative of membrane resistance to flow or fouling, increased. Accompanying the increase in TMP was an increase in the organic nonsettleable fraction (colloidal + dissolved) content of the mixed liquor and deterioration of permeate quality and floc strength. Permeate polysaccharide concentrations increased significantly, suggesting a preferential binding of solution polysaccharides by alum. Upon reinitiating alum addition, the TMP only partially recovered, indicating some irreversible fouling, while mixed liquor nonsettleable organic material, permeate quality, and floc strength returned to initial levels. These results suggest that direct alum addition to membrane bioreactors can improve membrane performance by reducing the organic fouling material and improving floc structure and strength. It appears that bulk liquid polysaccharides may contribute to irreversible membrane fouling, and this fraction can be efficiently controlled through the alum addition.     

Air pollution and lung diseases in Oporto Area

This area has a rate of patients with obstructive chronic lung disease that is the highest in Portugal and the second in Europe. Levels of pollution observed in 1985/86 and 1986/87 allowed evaluating the effects of concentrations lower than those that usually cause acute episodes. It was observed that even low levels of strong acidity can be related with lung diseases, when observed simultaneously with appreciable levels of black smoke; climatic factors have a synergetic effect.     

Valorization of EVA waste from footwear industry as natural aggregates substitutes in mortar: the effect of granulometry

Journal of Material Cycles and Waste Management - The increased consumption of polymers and the consequent generation of waste requires the development of efficient recycling strategies. In this...     

Synthesis of an organic–inorganic composite from calcium carbonate and Kraft lignin and its use as carrier material for controlled release of semiochemical agents

Environmental Science and Pollution Research - The control of pests in agricultural systems is currently based on the widespread use of pesticides that efficiently control pests but have negative...     

Mining Communities from a Resilience Perspective: Managing Disturbance and Vulnerability in Itabira,Brazil

This paper applies the resilience lens to a social–ecological system characterized by the presence of large-scale mineral extraction operations. The system in question is the Brazilian community of Itabira, Minas Gerais, host to an iron ore operation of Vale, the world’s second largest mining corporation. Utilizing a resilience assessment framework, this study describes the various components of the Itabira social–ecological system revealing the challenges brought about by mining’s dominance. Data collection included literature reviews and semi-structured interviews with 29 individuals representing different stakeholder groups. Findings revealed that, despite recent efforts by government to regulate the industry, the mine continues to generate press and pulse disturbances that impact the resilience of the community. Operating from the standpoint that resilience depends largely upon the management capacity of stakeholders, the research identifies three ways to improve mining governance in Itabira. First, there is a need for local government to have more power in dealings with the corporation. Concurrent with this power, however, the municipality must demonstrate ownership over its fate, ideally through the creation of a sustainability plan. Finally, all key parties must demonstrate commitment to cooperating to resolve outstanding disturbances, even when these fall outside the regulatory approval process. While Itabira will remain a mining town for the foreseeable future, actions taken now to address challenges will only strengthen community well-being and sustainability moving forward.