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Relationship among pollution concerns, attitudes toward social problems, and environmental perceptions in abandoned sites using Bayesian inferential analysis
2019
Kim, Eujin Julia | Kang, Youngeun
How do local community perceive pollution risk and social problems in abandoned areas? Which factors affect these risk perceptions? Among several factors affecting environmental perceptions, familiarity to places has long been known to positively affect landscape perception, but is this also true for abandoned area with scruffy vegetation and industrial remnants? Will long-term residents eventually adapt to and accept these neglected landscapes? In the past, efforts have largely been devoted to the cleanup of large, highly polluted areas. This left many smaller, less polluted sites, often in urban or suburban areas, relatively neglected. These areas, which typically consist of small abandoned industrial and commercial sites and vacant lots in neighborhoods, are problematic since people living nearby continue to suffer from urban blight. Recently, there has been a shift in the focus of brownfield programs from highly polluted post-industrial cleanup to local brownfield reuse. In this new environment, a participatory planning process that engages the community seems to have become more important. In order to better understand factors affecting community people’s risk perception and effectively engage community support for the better management of derelict sites, this study investigated the factors on local community perceptions of abandoned landscapes including the effect of familiarity (the length of residency) and other sociodemographic (gender and age). For the study, the 200 study participants in eight neighborhoods along the Rail Corridor Revitalization Project in the city of Roanoke, VA, were asked to participate in survey and evaluate scenes of three types of abandoned landscapes focusing on two aspects, preference and pollution concerns. The results of scene ratings showed that lower scene preferences were associated with scene concerns related to higher pollution. However, although age and gender were associated with participants’ preference ratings and attitudes toward social problems and pollution, there was no significant effect for the length of residency.
Afficher plus [+] Moins [-]Setal-epidermal, muscular and enzymatic anomalies induced by certain agrochemicals in the earthworm Eudrilus eugeniae (Kinberg)
2019
Samal, Suryasikha | Mishra, C. S. K. | Sahoo, Sunanda
Eudrilus eugeniae, the vermicomposing worm, is found in considerable numbers in agricultural fields in India due to their eventual transfer through vermimanure. These worms are very often exposed to pesticides, herbicides, chemical fertilisers and other soil amendments. This paper reports the effects of variable concentrations of urea, phosphogypsum (PG), paper mill sludge (PMS) and two organophosphorus agrochemicals, monocrotophos and glyphosate, on certain morphological, histological and biochemical parameters of E. eugeniae. Results indicated setal anomalies, epidermal lesions, clitellar swelling and constriction of the body. Disintegration of connective tissue, vacuolation of dermis and significant alterations in protein, lipid peroxidation levels and activities of lactate dehydrogenase, acetylcholinesterase and catalase have also been observed in the treated worms. It is proposed that setae, connective tissue, protein and enzymes in E. eugeniae could be useful markers to evaluate toxicity due to the test chemicals.
Afficher plus [+] Moins [-]Long-term spatiotemporal variations of atmospheric sulfur, nitrogen and particle pollutants in Chongqing, southwest China: implication of industrial transfer
2019
Peng, Ying | Cui, Jian | Zhu, Hongyun | Cao, Youhui | Du, Ke | Yao, Dongrui
Industrial transfer has swept through in China. However, there is still a knowledge gap about its environmental effects. In this study, industrial transfer status was assessed and evaluated by industrial ratios (%; the gross product contributions of the secondary industry to the whole industry) and the impact of such transfer on atmospheric environment (SO₂, NO₂, PM₁₀ (particles with aerodynamic diameter less than 10 μm), precipitations of SO₄²⁻, NO₃⁻, and NH₄⁺) in the 38 districts and counties in Chongqing was analyzed and discussed for the period of 2006–2015. Results showed that industries were transferred obviously from the main urban region (MUR) into the 1-h economic region (OHER). Atmospheric sulfur and PM₁₀ were efficiently put in control, but atmospheric nitrogen (NO₂; precipitations of NO₃⁻ and NH₄⁺) was increasing and posted a potential threat to air quality especially during 2011–2015. Correlations showed that industrial ratios had significantly positive relationships with concentrations of ambient SO₂ and PM₁₀ in the MUR and ambient NO₂ in the OHER (p < 0.05) while a remarkably negative one with concentrations of ambient SO₂ in the OHER (p < 0.05) during 2006–2015, implying that industrial transfer could be effective in transferring sulfur pollution but not as efficient in transferring atmospheric nitrogen and PM₁₀ pollutions as SO₂ between in the MUR and OHER. More measures should be taken to reduce nitrogen and PM₁₀ emission and a regional monitoring network of ambient NH₃ is in urgent need.
Afficher plus [+] Moins [-]Genotoxic, cytotoxic, and neurotoxic responses in Anodonta cygnea after complex metal mixture treatment
2019
Butrimavičienė, Laura | Stankevičiūtė, Milda | Kalcienė, Virginija | Jokšas, Kęstutis | Baršienė, Janina
Environmental effects associated with the release of various metals even at maximum permissible concentrations (MPC) to the aquatic ecosystems are evident. In the present work, time-dependent increase in accumulated metals amount in gills of Anodonta cygnea after exposure to complex metal (Zn 0.1, Cu 0.01, Ni 0.01, Cr 0.01, Pb 0.005, and Cd 0.005 mg/L, MPC accepted for the inland waters in EU) mixture at various time points (1, 2, 4, 7, 14, and 28 days) was investigated. Statistically significant increase of Cu and Cd was determined in mussel’s gills after 7-day exposure, in comparison to control group; moreover, significantly elevated concentration of Cu was measured and after 14-day treatment (in comparison to control and pre-exposure group). Concentrations of five (Cu, Ni, Cr, Pb, and Cd) out of 6 investigated metals were statistically increased in gills tissue after 28-day treatment. Moreover, complex metal mixture has demonstrated tissue- and time-dependent genotoxicity (∑Gentox) and cytotoxicity (∑Cytox) responses in mussels. After 4-day exposure, there were found the highest ∑Gentox levels in gills cells and haemocytes. Two-day treatment of mussels resulted in the highest and statistically significant induction of ∑Cytox level (in gills). Furthermore, after short-term (4 days) exposure, statistically significant inhibition of AChE activity in hemolymph of metal mixture–exposed mussels, in comparison to control and pre-exposure group, was found. Comparison of investigated responses in different tissue of A. cygnea discloses new information about metal mixture (at MPC) impacts at different treatment time. According to the obtained geno- and cytotoxicity data, it is suggested that gills are more sensitive tissue. Environmentally relevant trace metal concentrations when existing in mixture are able to cause adverse effects in A. cygnea; therefore, biological effects at different levels of organism are expected as a realistic scenario.
Afficher plus [+] Moins [-]Spatiotemporal variation and influencing factors of vegetation cover in the ecologically fragile areas of China from 2000 to 2015: a case study in Shaanxi Province
2019
Feng, Dingrao | Wang, Jinman | Fu, Meichen | Liu, Guangchao | Zhang, Min | Tang, Rongbin
China’s Loess Plateau region has a weak ecological environment, and the government has invested a considerable amount of money to repair the ecological environment. Vegetation plays an important role in the ecological environment. The Sen slope analysis and the Mann-Kendall trend test were used to analyze the trend and significance of vegetation coverage from 2000 to 2015. The vegetation coverage was analyzed to investigate the influence of land use types and conversion. The Pearson Correlation Test and qualitative analysis were utilized at the pixel and regional scales to investigate the influence of meteorological factors and topographical factors. The fluctuation of vegetation in Shaanxi was analyzed from 2000 to 2015. The impact of anthropogenic activities was investigated using residual trend analysis. Hurst exponent and H/S analysis were applied to investigate the potential future vegetation coverage trend. The vegetation coverage in Shaanxi Province improved from 2000 to 2015. In unchanged land use types, all types showed significant improvements expect for other construction land. In changed land use types, most of the land use types converted into urban land showed degradation. All the land use types converted into dry land, forest, and unused land showed improvements. Ecological protection has achieved great results. Precipitation and temperature partly affect vegetation coverage in Shaanxi. Gradients and elevation affected the distribution of vegetation coverage and human activities influenced land use type and the ecological environment. In the future, potential degradation risks still exist in the parts of Shaanxi Province.
Afficher plus [+] Moins [-]Physiological damages of Sargassum cymosum and Hypnea pseudomusciformis exposed to trace metals from mining tailing
2019
Costa, Giulia Burle | Ramlov, Fernanda | de Ramos, Bruna | Koerich, Gabrielle | Gouvea, Lidiane | Costa, Patrícia Gomes | Bianchini, Adalto | Maraschin, Marcelo | Horta, Paulo A. Jr
The damages of Mariana’s mining mud in the physiology of the brown algae Sargassum cymosum and its main epiphytic, the red algae Hypnea pseudomusciformis, were evaluated by controlled essays. Seaweeds were exposed to presence or absence of mud, isolated or in biological association, for 5 and 15 days. Measured parameters were growth rates, biochemical descriptors, and the chemical investigation of concentration and metal profile of the mud dissolved in seawater. Results showed that the highest values for metals were Al > Fe > Mn > Zn in both exposure periods. The mud also affected the growth rate with lethality in both isolated and associative treatments with H. pseudomusciformis after 15 days. According to our redundancy analysis (RDA), the profile and concentration of all metallic elements can induce different physiological responses of the organisms. We were able to observe a higher physiological adaptive ability of S. cymosum against the long-term presence of metals by the synthesis of phenolic compounds, while the deviation of metabolic routes in H. pseudomusciformis can be addressed as the main responsible for its lethality. Moreover, the presence of Hypnea in associative treatments reduces Sargassum’s detoxification ability. The present results reinforce the importance of biological interaction studies in a context of physiological resilience against mining mud pollution and mutual influences of species over the individual ability to avoid oxidative stress.
Afficher plus [+] Moins [-]Bioconcentration studies with the freshwater amphipod Hyalella azteca: are the results predictive of bioconcentration in fish?
2019
Schlechtriem, Christian | Kampe, Sebastian | Bruckert, H.-J. (Hans-Jörg) | Bischof, Ina | Ebersbach, Ina | Kosfeld, Verena | Kotthoff, Matthias | Schäfers, Christoph | L’Haridon, Jacques
Bioconcentration factors (BCF) for regulatory purposes are usually determined by fish flow-through tests according to technical guidance document OECD 305. Fish bioconcentration studies are time consuming, expensive, and use many laboratory animals. The aim of this study was to investigate whether the freshwater amphipod Hyalella azteca can be used as an alternative test organism for bioconcentration studies. Fourteen substances of different hydrophobicity (log Kₒw 2.4–7.6) were tested under flow-through conditions to determine steady state and kinetic bioconcentration factors (BCFₛₛ and BCFₖ). The results were compared with fish BCF estimates for the same substances described in the literature to show the relationship between both values. Bioconcentration studies with the freshwater amphipod H. azteca resulted in BCF estimates which show a strong correlation with fish BCF values (r² = 0.69). Hyalella BCF values can be assessed in accordance with the regulatory B criterion (BCF > 2000, i.e., REACH) and thereby enable the prediction of B or non-B classification in the standard fish test. Therefore, H. azteca has a high potential to be used as alternative test organism to fish for bioconcentration studies.
Afficher plus [+] Moins [-]Assessment of occupational exposure to pesticide mixtures with endocrine-disrupting activity
2019
Wong, Hie Ling | Garthwaite, David G. | Ramwell, Carmel T. | Brown, Colin D.
Occupational exposure to pesticide mixtures comprising active substance(s) and/or co-formulant(s) with known/possible endocrine-disrupting activity was assessed using long-term activity records for 50 professional operators representing arable and orchard cropping systems in Greece, Lithuania, and the UK. Exposure was estimated using the harmonised Agricultural Operator Exposure Model, and risk was quantified as a point of departure index (PODI) using the lowest no observed (adverse) effect level. Use of substances with known/possible endocrine activity was common, with 43 of the 50 operators applying at least one such active substance on more than 50% of spray days; at maximum, one UK operator sprayed five such active substances and 10 such co-formulants in a single day. At 95th percentile, total exposure was largest in the UK orchard system (0.041 × 10⁻² mg kg bw⁻¹ day⁻¹) whereas risk was largest in the Greek cropping systems (PODI 0.053 × 10⁻¹). All five cropping systems had instances indicating potential for risk when expressed at a daily resolution (maximum PODI 1.2–10.7). Toxicological data are sparse for co-formulants, so combined risk from complex mixtures of active substances and co-formulants may be larger in reality.
Afficher plus [+] Moins [-]Soil water content and pH drive archaeal distribution patterns in sediment and soils of water-level-fluctuating zones in the East Dongting Lake wetland, China
2019
Li, Wei | Feng, Defeng | Yang, Gang | Deng, Zhengmiao | Rui, Junpeng | Chen, Huai
Archaea play a vital role in Earth’s geochemical cycles, but the factors that drive their distribution between sediments and water-level-fluctuating zones in the East Dongting Lake (EDL) wetland are poorly understood. Here, we used Illumina MiSeq to investigate the variation in the soil archaeal community structure and diversity among sediments and four water-level-fluctuating zones (mudflat, sedge, sedge-Phragmites, and Phragmites) in the EDL wetland. Diverse archaeal assemblages were found in our study, Crenarchaeota, Euryarchaeota, and ammonia-oxidizing and methanogenic subset were the dominant groups, and all their abundances shifted from sediment to water-level-fluctuating zones. The principal coordinates analysis and cluster analysis showed that the overall archaeal community structure was separated into two clusters: cluster I contained nine samples from sediment, mudflat, and sedge zones, whereas cluster II contained six samples from sedge-Phragmites and Phragmites zones. Archaeal diversity was significantly highest in sediment and lowest in Phragmites zone soils. The Mantel test showed that the variation in archaeal community structure was significantly positively correlated with soil water content and pH. The relative abundances of Crenarchaeota and Nitrososphaerales decreased with soil water content, while Euryarchaeota and Methanomicrobiales increased with soil water content. The relative abundance of Methanomicrobiales significantly decreased with pH (R² = 0.34–0.48). Chao 1, observed operational taxonomic units, Shannon index, and Simpson index all correlated significantly positively with water content (R² = 0.40–0.60), while Shannon and Simpson indexes both correlated significantly negatively with pH (R² = 0.20–0.37). Our results demonstrated that the variations in the archaeal community structure were markedly driven by soil water content and pH in the EDL wetland. Our findings suggested that archaeal communities shifted among sediment and four water-level-fluctuating zones, highlighting that the spatiotemporal heterogeneity of greenhouse gas flux in small scale should be taken into account for accurate prediction of greenhouse gas emissions in the Dongting Lake area, especially on the background of climate change and human activities.
Afficher plus [+] Moins [-]A new remote sensing index based on the pressure-state-response framework to assess regional ecological change
2019
Hu, Xisheng | Xu, Hanqiu
Ecological indicators have widespread appeal to scientists, environmental managers, and the general public. Remote sensing is unique in its capability to record variety of spatio-temporal information on land surface with complete coverage, especially with regard to larger spatial scales, which has been proven to be an effective data source to create indicators to rapidly identify regional eco-environment. In this paper, a new index, remote sensing based ecological index (RSEI) based on the pressure-state-response (PSR) framework, was applied to assess regional ecological changes in Fuzhou City of Fujian Province, southeastern China, using Landsat ETM+/OLI/TIRS images. Taking the advantages of being totally free of artificial interference in the calculation using principal components analysis (PCA) to assign weights of each variable, the RSEI can assess the regional ecological status more objectively and easily. The effectivity of the new index was validated by four approaches, including point-based, classification-based, correlation-based, and urban-rural-gradient-based comparisons. The case study showed that Fuzhou has witnessed ecological improvement during the study period, with the value of RSEI increasing from 0.663 in 2000 to 0.675 in 2016. Spatial variation analysis showed that the poor level of RSEI distributed mostly in the central urban areas, and the ecological degradation was attributed to the fast expansion of the built-up area, characterized by increasing greatly in the value of the normalized differential built up and soil index (NDBSI) in such areas.
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