Novel polyol initiator from polyurethane recycling residue

Flexible polyurethane foams can be advantageously treated by two-phase glycolysis in order to recover polyols with improved quality. The bottom phase obtained, which contains highly toxic reaction by-products and the excess glycol, presents an environmental and economic problem which should be solved. The main purpose of this work is the development of process for the valorization of these by-products, converting them in non-dangerous and profitable substances. For this process, most of the glycol can be recovered by means of vacuum distillation in order to reuse it in the glycolysis. On the other hand, the vacuum residue, containing the isocyanate part of the glycolysis by-products, was assayed as initiator in the synthesis of new polyols. Propoxylation of the initiator was carried out in different experimental conditions to obtain several polyether-polyols. Rigid polyurethane foams with suitable technical properties were synthesized with those polyols synthesized with the dangerous glycolysis by-products.     

Projecting canopy cover change in Tasmanian eucalypt forests using dynamically downscaled regional climate models

Loss of forest cover is a likely consequence of climate change in many parts of the world. To test the vulnerability of eucalypt forests in Australia’s island state of Tasmania, we modelled tree canopy cover in the period 2070–2099 under a high-emission scenario using the current climate–canopy cover relationship in conjunction with output from a dynamically downscaled regional climate model. The current climate–canopy cover relationship was quantified using Random Forest modelling, and the future climate projections were provided by three dynamically downscaled general circulation model (GCM) simulations. Three GCMs were used to show a range of projections for the selected scenario. We also explored the sensitivity of key endemic and non-endemic Tasmanian eucalypts to climate change. All GCMs suggested that canopy cover should remain stable (proportional cover change <10 %) across ~70 % of the Tasmanian eucalypt forests. However, there were geographic areas where all models projected a decline in canopy cover due to increased summer temperatures and lower precipitation, and in addition, all models projected an increase in canopy cover in the coldest part of the state. The model projections differed substantially for other areas. Tasmanian endemic species appear vulnerable to climate change, but species that also occur on the mainland are likely to be less affected. Given these changes, restoration and carbon sequestration plantings must consider the species and provenances most suitable for future, rather than present, climates.     

Corporate social responsibility in the mining industry: Perspectives from stakeholder groups in Argentina

Since the liberalisation of its investment regime in the 1990s, Argentina has seen a rise in foreign direct investment into large-scale exploration and exploitation of mineral resources. However, many social groups (local communities, grassroots movement and the church) often strongly oppose new mining projects on the grounds of environmental, ethical and economic concerns. In a situation marked by widespread conflict, mining companies continue operating and develop Corporate Social Responsibility (CSR) initiatives which are often promoted as a means of contributing to the sustainability and development of the nation. The paper develops a framework to highlight how the principles of stakeholder theory could be used as conceptual and practical guidance for conflict-resolution oriented CSR policies. The framework is further used to analyse two case studies of conflictive mining projects in Argentina. The paper explores how key stakeholders perceive contribution of CSR to welfare and the socio-economic development of mining communities and sustainable development of the nation. It demonstrates that institutional and social stakeholder networks often strongly oppose the idea of voluntary self-regulation implied by CSR in situations characterised by weak governance. Even though the CSR of companies could be improved in areas of corporate communication, transparency, stakeholder engagement and dialogue, it is not seen as a panacea for the social conflicts in the sector.     

Pattern recognition and classification of sediments according to their metal content using chemometric tools. A case study: the estuary of Nerbioi-Ibaizabal River (Bilbao, Basque Country)

Chemometrics are increasingly used in environmental monitoring studies, but are still far from being accepted as routine tools by field specialists. The multivariate character of usually highly correlated environmental data recommends the use of advanced chemometrics as part of the analytical methodology in order to get information on the basic structure of data. In this work, we have applied a battery of non-supervised (Principal Component Analysis (PCA)) and supervised (k-Nearest Neighbour (k-NN), Soft Independent Modelling of Class Analogies (SIMCA), Linear Discriminant Analysis (LDA) and Artificial Neural Networks (ANNs)) multivariate techniques on a specific environmental dataset. The dataset consists on the concentration of 14 elements (Al, As, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sn, V and Zn) in 95 sediments collected at eight different locations of the estuary of the Nerbioi-Ibaizabal River (Bilbao, Basque Country) during 12 sampling campaigns conducted every 3 months between 2005 and 2008. The study aims to present a simple methodology of general applicability which may result in a flexible and practical tool to assess chemical pollution in sediments of a given specific site.     

Veterinary drugs in groundwater in a dairy region of central Argentina and risk assessment for human health

Veterinary drugs used in dairy production are potential contaminants of surface or groundwater sources, being able to affect human and environmental health. It is known that chronic exposure to antibiotics in low concentrations present in water can generate microbial resistance. This study aimed to evaluate the presence of veterinary drugs in 53 groundwater samples used for animal and human consumption, collected in dairy milking parlors, in an important milk-producing area of central Argentina, and to assess the risk to human health when they are used as drinking water. In 75% of the total samples analyzed, at least one veterinary drug was detected. The most frequently found drugs in water samples were the antibiotics tetracycline in 58.5% and oxytetracycline in 56.6%, and an anti-inflammatory, flunixin in 39.6%. In the water samples, the tetracycline and oxytetracycline concentrations were between 0.1 and 5.3 μg/L and flunixin concentrations were between 0.01 and 2.1 μg/L. The frequency of appearance and the concentration levels of the substances found in the water samples were evaluated according to the productivity, size, and production system (confined or pasture) of the dairy farms. Higher concentrations and proportions of water samples containing antibiotics were observed when the number of animals per dairy farm was >182 and when the productivity was high (>25 liters per animal per day). In the case of flunixin, the percentage of detection was similar in all evaluated categories. The risk assessment for children and adults, considering the intake of drinking water containing residues of these drugs, did not indicate a significant health risk. It would be advisable to evaluate other sources of drinking water, both surface and underground, in other regions of the country, to provide data to assess the impact of these substances and the other contaminants on environmental and human health.     

Zoning a Protected Area: Proposal Based on a Multi-thematic Approach and Final Decision

The Madrid Regional Government (Central Spain) proposes a zone of the Guadarrama Mountains to be declared as a National Park. This paper reports on the zoning method developed to this end. The procedure followed considers compatibility of land uses with landscape characteristics and proposes protecting a part of the zone through declaration of National Park status and declaring another part as a Regional Park. The approach is based upon a multivariate environmental analysis aimed at zoning for optimal location of potential activities. The zoning permits the design of protected areas following the criteria underlying the declaration of these two categories in accordance with the Spanish environmental legislation in force. A practical tool for policy decision-making is provided. However, the final decision taken by policymakers in the design and zoning of protected areas differed from the model output used by the scientists. This is discussed in the paper to illustrate the interactions between political decision-making and scientific modelling.     

Assessment of the levels of DDT and DDE in soil and blood samples from Tabasco, Mexico

In Mexico, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) was used until the year 2000, principally in agriculture and anti-paludal program health campaigns. The southeastern region of Mexico was an important area of malaria, and from 1957 DDT was applied indoors every 6?months, with a coverage of 2?g/m². The current study was performed in Tabasco, a Mexican state located in the southeastern region of Mexico. DDT and 1,1-dichloro-2,2-bis(4-chlorophenyl)ethene (DDE) were analyzed by gas chromatography/mass spectrometry. In general, low levels were found in household outdoor samples; the levels of DDT ranged from not detectable to 0.048?mg/kg, and of DDE from 0.001 to 0.068?mg/kg. An important finding was that, in all communities where DDT in blood was analyzed, exposure to DDT was found, indicating both past and present exposure. Although the levels found in this study were lower than other studies in Mexico, there is a need to evaluate whether the people living in the study area are at risk.     

Monitoring and assessment of wetlands using Earth Observation: the GlobWetland project

The overall objective of the Ramsar Convention, signed in 1971, is the conservation and wise use of wetlands by national action and international cooperation as a means to achieving sustainable development. This complex and challenging task requires national, local and international bodies involved in the implementation of the convention to rely on suitable geo-information to better understand wetland areas, complete national inventories, perform monitoring activities, carry out assessments and put in practice suitable management plans based on updated and reliable information. In the last years, Earth Observation (EO) technology has been revealed as a key tool and unique information source to support the environmental community in different application domains, including wetlands' conservation and management. In this context, the European Space Agency (ESA) in collaboration with the Ramsar Secretariat launched in 2003 the "GlobWetland" project in order to demonstrate the current capabilities of Earth Observation technology to support inventorying, monitoring, and assessment of wetland ecosystems. This paper collects the main results and findings of the "GlobWetland" project, providing an overview of the current capabilities and limits of EO technology as a tool to support the implementation of the Ramsar Convention. The project was carried out in collaboration with several regional, national and local conservation authorities and wetland managers, involving 50 different wetlands across 21 countries on four continents. This large range of users provided an excellent test bed to assess the potential of this technology to be applied in different technical, economic and social conditions.     

Effects of elevated atmospheric CO2 on invasive plants: comparison of purple and yellow nutsedge (Cyperus rotundus L. and C. esculentus L.)

The rise in atmospheric CO(2) concentration coupled with its direct, often positive, effect on the growth of plants raises the question of the response of invasive plants to elevated atmospheric CO(2) levels. Response of two invasive weeds [purple nutsedge (Cyperus rotundus L.) and yellow nutsedge (Cyperus esculentus L.)] to CO(2) enrichment was tested. Plants were exposed to ambient (375 micromol mol(-1)) or elevated CO(2) (ambient + 200 micromol mol(-1)) for 71 d in open top chambers. Photosynthetic rate did not differ between CO(2) treatments for either species. Conductance was lower in purple nutsedge and tended to be lower in yellow nutsedge. Purple nutsedge had higher instantaneous water use efficiency; a similar trend was noted for yellow nutsedge. Purple nutsedge had greater leaf area, root length and numbers of tubers and tended to have more tillers under high CO(2). In yellow nutsedge, only tuber number increased under CO(2) enrichment. Leaf dry weight was greater for both species when grown under elevated CO(2). Only purple nutsedge made seed heads; CO(2) level did not change seed head dry weight. Root dry weight increased under the high CO(2) treatment for purple nutsedge only, but tuber dry weight increased for both. Total dry weight of both species increased at elevated CO(2). Purple nutsedge (under elevated CO(2)) tended to increase allocation belowground, which led to greater root-to-shoot ratio (R:S); R:S of yellow nutsedge was unaffected by CO(2) enrichment. Findings suggest both species, purple more than yellow nutsedge, may be more invasive in a future high-CO(2) world.     

Soil carbon stock estimations: methods and a case study of the Maranhão State,Brazil

Environment, Development and Sustainability - Soils feature significant variations in soil carbon stocks through land-use changes, management practices, and intrinsic characteristics. The aim of...