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941.
Metal contamination is a recurring problem in Peru, caused mainly by mine tailings from a past active mining activity. The Ancash region has the largest number of environmental liabilities, which mobilizes high levels of metals and acid drainages into soils and freshwater sources, posing a standing risk on human and environmental health. Native plant species spontaneously growing on naturally acidified soils and acid mine tailings show a unique tolerance to high metal concentrations and are thus potential candidates for soil phytoremediation. However, little is known about their propagation capacity and metal accumulation under controlled conditions. In this study, we aimed at characterizing nine native plant species, previously identified as potential hyperaccumulators, from areas impacted by mine tailings in the Ancash region. Plants were grown on mine soils under greenhouse conditions during 5 months, after which the concentration of Cd, Cu, Ni, Pb, and Zn was analyzed in roots, shoots, and soils. The bioaccumulation (BAF) and translocation factor (TF) were calculated to determine the amount of each metal accumulated in the roots and shoots and to identify which species could be better suited for phytoremediation purposes. Soil samples contained high Cd (6.50–49.80 mg/kg), Cu (159.50–1187.00 mg/kg), Ni (3.50–8.70 mg/kg), Pb (1707.00–4243.00 mg/kg), and Zn (909.00–7100.00 mg/kg) concentrations exceeding national environmental quality standards. After exposure to mine tailings, concentrations of metals in shoots were highest in Werneria nubigena (Cd, 16.68 mg/kg; Cu, 41.36 mg/kg; Ni, 26.85 mg/kg; Zn, 1691.03 mg/kg), Pennisetum clandestinum (Pb, 236.86 mg/kg), and Medicago lupulina (Zn, 1078.10 mg/kg). Metal concentrations in the roots were highest in Juncus bufonius (Cd, 34.34 mg/kg; Cu, 251.07 mg/kg; Ni, 6.60 mg/kg; Pb, 718.44 mg/kg) and M. lupulina (Zn, 2415.73 mg/kg). The greatest BAF was calculated for W. nubigena (Cd, 1.92; Cu, 1.20; Ni, 6.50; Zn, 3.50) and J. bufonius (Ni, 3.02; Zn, 1.30); BCF for Calamagrostis recta (Cd, 1.09; Cu, 1.80; Ni, 1.09), J. bufonius (Cd, 3.91; Cu, 1.79; Ni, 18.36), and Achyrocline alata (Ni, 137; Zn, 1.85); and TF for W. nubigena (Cd, 2.36; Cu, 1.70; Ni, 2.42; Pb, 1.17; Zn, 1.43), A. alata (Cd, 1.14; Pb, 1.94), J. bufonius (Ni, 2.72; Zn, 1.63), and P. clandestinum (Zn, 1.14). Our results suggest that these plant species have a great potential for soil phytoremediation, given their capability to accumulate and transfer metals and their tolerance to highly metal-polluted environments in the Andean region.  相似文献   
942.
Can ecological distribution conflicts turn into forces for sustainability? This overview paper addresses in a systematic conceptual manner the question of why, through whom, how, and when conflicts over the use of the environment may take an active role in shaping transitions toward sustainability. It presents a conceptual framework that schematically maps out the linkages between (a) patterns of (unsustainable) social metabolism, (b) the emergence of ecological distribution conflicts, (c) the rise of environmental justice movements, and (d) their potential contributions for sustainability transitions. The ways how these four processes can influence each other are multi-faceted and often not a foretold story. Yet, ecological distribution conflicts can have an important role for sustainability, because they relentlessly bring to light conflicting values over the environment as well as unsustainable resource uses affecting people and the planet. Environmental justice movements, born out of such conflicts, become key actors in politicizing such unsustainable resource uses, but moreover, they take sometimes also radical actions to stop them. By drawing on creative forms of mobilizations and diverse repertoires of action to effectively reduce unsustainabilities, they can turn from ‘victims’ of environmental injustices into ‘warriors’ for sustainability. But when will improvements in sustainability be lasting? By looking at the overall dynamics between the four processes, we aim to foster a more systematic understanding of the dynamics and roles of ecological distribution conflicts within sustainability processes.  相似文献   
943.
In the global map of environmental injustices (http://www.ejatlas.com), the Andean countries (AC) report many ecological distribution conflicts. Our hypothesis is that the patterns of such conflicts are explained by the structural shifts of the economies and the concomitant changes in their metabolic profiles. Since the 1990s, these countries went through a strong reprimarization process, which changed their social metabolism as well as intensified environmental pressures and conflicts. In monetary terms, in the AC group of countries (Colombia, Ecuador, Peru and Bolivia), the primary sector increased its importance both in exports as well as in GDP. In the metabolic dynamics, the Domestic Extraction of materials (measured in tons) increased by a factor of 3.4 after jumping from 336 to 1145 MT between 1970 and 2012. This was driven by the fossil fuel and mining sectors. This reality was reflected in the environmental conflicts. Mining, fossil fuels, biomass and hydropower plants are the most conflictive sectors. The research in this article relies on a study of material flow analysis for the four AC carried out by the authors as well as 244 environmental conflicts reported in the EJAtlas until August 2016. The shifts in the metabolic–economic patterns help explain the dynamics and characteristics of the environmental conflicts in the AC. Such conflicts produce social mobilizations, which if successful, might help move society towards sustainability and environmental equity.  相似文献   
944.
Fragile coastal areas suffer from human activities. Environmental quality is one of the most important aspects in a tourist destination of sun and sand. The quality of bathing water and sand became indicators in the worldwide competition of beach destinations. We studied the water and sand quality along the beach of Puerto Velero, in northern Colombia. Water and sand beach quality were monitored during thirteen months. This allowed identifying the most significant sources of pollution along the beach, and understanding the interrelationship between tourism and the effects on the environment. Linear correlations allow assessing the association between the number of visitors and the physicochemical and microbiological parameters. The number of visitors was directly correlated with the presence of grease and oils, both in water and sand, as well as with fecal coliforms in water. A relation between the suspended solids and the presence of fecal coliforms in water and sand was observed. This statistical approach allows understanding the origin of beach sand and swimming water pollution at tourist beaches. Overall, sand quality has an important influence and is directly related to the water quality of the beach. Both the number of tourists and their activities are main factors explaining the contamination of the water and sand. This shows the importance of management of waste and wastewater in combination with awareness raising initiatives. More research should include monitoring and evaluating of both water and sand beach and provide data to revise the existing legal framework.  相似文献   
945.

Local, regional, and global processes affect deforestation and land-use changes in the Brazilian Amazon. Characteristics are: direct conversions from forest to pasture; regional processes of indirect land-use change, described by the conversion of pastures to cropland, which increases the demand for pastures elsewhere; and teleconnections, fueled by the global demands for soybeans as animal fodder. We modeled land-use changes for two scenarios Trend and Sustainable Development for a hot spot of land-use change along the BR-163 highway in Mato Grosso and Pará, Brazil. We investigated the differences between a coupled modeling approach, which incorporates indirect land-use change processes, and a noncoupled land-use model. We coupled the regional-scale LandSHIFT model, defined for Mato Grosso and Pará, with a subregional model, alucR, covering a selected corridor along the BR-163. The results indicated distinct land-use scenario outcomes from the coupled modeling approach and the subregional model quantification. We found the highest deforestation estimates returned from the subregional quantification of the Trend scenario. This originated from the strong local dynamics of past deforestation and land-use changes. Land-use changes exceeded the demands estimated at regional scale. We observed the lowest deforestation estimates at the subregional quantification of the Sustainable Development story line. We highlight that model coupling increased the representation of scenario outcomes at fine resolution while providing consistency across scales. However, distinct local dynamics were explicitly captured at subregional scale. The scenario result pinpoints the importance of policies to aim at the cattle ranching sector, to increase land tenure registration and enforcement of environmental laws.

  相似文献   
946.
Regional Environmental Change - Vegetation actively affects different components of the water budget in multiple spatial and temporal scales. Changes in vegetation cover and structure—such as...  相似文献   
947.
The term ‘sustainability science’ has been employed to refer to a scientific trend, movement or program aimed at studying problems related to human–nature interactions. However, since it does not have its own set of principles for knowledge building and lack of a definition of a study object, sustainability science is not a science, at least in the usual sense of the word. A study object is the conceptual delimitation of the problems tackled by a science, and therefore, its search in the context of a science of sustainability requires exploring different notions of sustainability. This article presents different perspectives on the concept of sustainability and analyzes the viability to assume them as study object of sustainability science. Such exploration demands concepts based on a processual ontology that directs the researcher toward the dynamic, historic and temporal and social-ecological character of problems of unsustainability. The concept of social-ecological resilience seems to comply with such requirements.  相似文献   
948.
To examine how citizen-driven initiatives for sustainability strive to bring about change and spread their practices, efforts to link social movement, grassroots innovation and green-consumption movements theory are built upon. Göteborg’s citizen-driven waste-prevention initiatives, such as food waste recovery, creating common reuse spaces in housing blocks, exchanging used toys and repairing abandoned bicycles, are considered with data from observations, workshops, documents, social media communications and in-depth interviews. Citizen-driven initiatives succeeded in mobilizing material resources, displaying and reframing various rationales, and creating collaborative local networks to develop their waste-prevention practices. These practices infiltrated the municipal administration, matching incipient institutional mandates to minimize waste. By so doing, they bring within mainstream institutions radical rationales that can become activated in the future, contributing to diachronic change.  相似文献   
949.
Thallium is a non-essential metal with a wide range of industrial uses. However, thallium is also a potential pollutant with high potential toxicity to humans. In the present study, we analyzed and compared the cellular and genotoxic effects of thallium in two main oxidation states by applying chromosome aberration assays to human peripheral lymphocytes. We observed that thallium(I) sulfate reduced the mitotic index at all tested concentrations (0.5, 1, 5, 50 and 100 μg/mL), whereas thallium(III) chloride was toxic at concentrations ≥1 μg/mL. Thallium(I) and thallium(III) treatment significantly increased structural chromosomal aberrations, with and without gaps, and increased the percentage of aberrant cells without gaps. Furthermore, satellite associations and numerical chromosomal aberration tests showed significant differences at a few of the tested concentrations. The satellite association test is related to aneuploidy. Thallium salts increased satellite associations when hyperploid cells were observed. Our results indicated that the two oxidation states of thallium induced toxicity in vitro – i.e. cyto/genotoxic (clastogenic and aneuploidogenic) effects.  相似文献   
950.
Environmental Science and Pollution Research - Excess copper (Cu) in soils has deleterious effects on plant growth and can pose a risk to human health. In the last decade, legume-rhizobium...  相似文献   
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