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991.
The management of swine manure is becoming an important environmental issue in Chile. One option for the final disposal of
manure is to use it as a biofertilizer, but this practice could impact the surrounding environment. To assess the potential
environmental impacts of the use of swine manure as a biofertilizer, we propose a method to identify zones of environmental
risk through indices. The method considers two processes: nutrient runoff and solute leaching, and uses available information
about soils, crops and management practices (irrigation, fertilization, and rotation). We applied the method to qualitatively
assess the environmental risk associated with the use of swine manure as a biofertilizer in an 8,000-pig farm located in Central
Chile. Results showed that the farm has a moderate environmental risk, but some specific locations have high environmental
risks, especially those associated with impacts on areas surrounding water resources. This information could assist the definition
of better farm-level management practices, as well as the preservation of riparian vegetation acting as buffer strips. The
main advantage of our approach is that it combines qualitative and quantitative information, including particular situations
or field features based on expert knowledge. The method is flexible, simple, and can be easily extended or adapted to other
processes. 相似文献
992.
Mariagrazia D’Emilio Rosa Caggiano Rosa Coppola Maria Macchiato Maria Ragosta 《Environmental monitoring and assessment》2010,169(1-4):619-630
The development of in situ, cheep, noninvasive, and fast strategies for soil monitoring is a crucial task for environmental research. In this paper, we present the results of three field surveys carried out in an industrial area of Southern Italy: S. Nicola di Melfi. The monitoring procedure is based on soil magnetic susceptibility measurements carried out by means of experimental protocols that our research group developed during the last years. This field surveys is supported by both geological characterization of the area and analytical determinations of metal concentrations in soils. Magnetic studies were carried out not only in situ but also in laboratory. Results show that, taking into account the influence due to the geomorphologic difference, soil magnetic susceptibility is an optimal indicator of the anthropogenic impact. So, our monitoring strategy discloses that the combined use of magnetic susceptibility measurements and soil geomorphology information may be used as a useful tool for the temporal monitoring of pollution evolution and for a fast screening of polluted zones. 相似文献
993.
Paula Cristina Resende Paulo Resende Miguel Pardal Salomé Almeida Ulisses Azeiteiro 《Environmental monitoring and assessment》2010,170(1-4):535-544
Diatoms and macroinvertebrates have been extensively used as water quality indicators in Europe for the last two decades. In Portugal, the use of biological indicators to assess water quality in rivers has increased greatly. The aim of this work was to assess the water quality and ecological status of the Ul River in order to evaluate its ability for the establishment of a fluvial beach, using periphytic diatoms and macroinvertebrates as indicators. Four sites were selected along the Ul River. At each site, biological, physical, and chemical parameters were investigated. Epilithic diatoms and macroinvertebrates were sampled. The Specific Polluosensitivity Index and the Biological Diatom Index were applied to diatom data, while for macroinvertebrates, the Iberian Biological Monitoring Working Party (IBMWP) was used. According to the results obtained, it was possible to conclude that up to now, this river does not possess the ideal conditions for the establishment of a fluvial beach. We concluded that epilithic diatoms and macroinvertebrates provided consistent information on water quality assessment and can be used as biological indicators of the water quality in Ul River. 相似文献
994.
Pasture selection by livestock is an essential topic for rangeland management, especially in trace element-contaminated soils.
We have studied the composition (nutrients and trace elements) of a grass-based diet from soils affected by a mine spill at
different growth stages (October 2008 to May 2009). A diet based on other plants (mainly Compositae species) was also studied (May 2009) for comparison. Faeces and mane hair of horses feeding on these pastures were also analysed.
Micronutrient (Cu, Fe, Mn and Zn) and potentially toxic trace element (As, Cd, Pb, Tl) concentrations were below the maximum
tolerable levels (MTL) for horses, except for Fe (at early growth of pastures) and Cd (in the diet based on ‘other’ plants).
Values of potential ingestion of Fe by horses were higher than 10 mg kg body weight − 1 day − 1. Cadmium concentrations in some pasture samples (those composed of Compositae species) were higher than 3 mg kg − 1. Potential toxicity of such Cd levels in pastures is uncertain, since a high disparity of criteria about MTL by cattle exists
(between 0.5 and 10 mg kg − 1 diet). Nutrient concentrations were adequate for horses, which could counteract possible harmful effects derived from trace
element ingestion. The analyses of excreta and mane hair point to the low risk of toxicity derived from the consumption of
these contaminated pastures. However, the ingestion of regenerating pastures (autumnal samples) should be avoided due to the
greater risk of ingestion of contaminated soil attached to the plant material. Management of these pastures by grazing requires
periodic monitoring. Special attention should be given to Fe and particularly Cd (non-essential element) which accumulates
in animal organs, where it could provoke uncertain long-term effects. 相似文献
995.
Cachada A Pereira ME Ferreira da Silva E Duarte AC 《Environmental monitoring and assessment》2012,184(1):15-32
Urban and industrial development has caused a major impact on environmental soil quality. This work assesses the extent and
severity of contamination in a small urban area subjected to an industrial impact and identifies the major anthropogenic inputs.
Twenty-six soil samples were collected from agricultural and urban sites, and concentrations of potentially toxic elements
(As, Cd, Cu, Cr, Fe, Mn, Ni, Pb and Zn), PAHs and PCBs, were determined. In spite of the low median concentrations observed,
some sites represent a potential hazard for human health and ecosystems. Concentrations of contaminants were higher than those
found in a nearby city, indicating that the study area is affected by the surrounding industry. The use of multivariate statistical
analyses allowed for the identification of the main factors controlling the variability of potentially toxic elements and
organic pollutants in the soils. The presence of Cr, Fe, Mn and Ni was associated with geogenic inputs, and Cu, Pb, Zn, As,
PAHs and PCBs were associated with anthropogenic inputs. Industry and traffic were the most important anthropogenic sources.
Soil characteristics were identified as important factors controlling the spatial variability of elements, both from recognised
natural and anthropogenic origin. Differences between land uses were observed, which may be attributed to both management
practices and proximity to sources. 相似文献
996.
Gomes LN Oliveira SM Giani A von Sperling E 《Environmental monitoring and assessment》2012,184(8):4635-4645
The water reservoir of Vargem das Flores, Brazil, has been subject to eutrophication problems. The occurrence of cyanobacterial blooms in this water body has raised concerns regarding the presence of toxic metabolites. In order to understand the factors that promote the proliferation and distribution of cyanobacteria in the reservoir, physicochemical parameters, species composition, and toxicity of the reservoir water column were analyzed at monthly intervals over a 3-year period (2004-2007) using a range of analytical techniques. The results showed that cyanobacteria were absent in the dry period, returning after the onset of stratification. A succession pattern was observed within this group. The Aphanocapsa genus was dominant in the last rainy period of the study (October 2006 to March 2007). However toxicity was only detected when the genera Microcystis and Sphaerocavum were present (October 2005). The principal components analysis showed negative correlation between cyanobacteria and orthophosphate. The change of dominant cyanobacteria along the 3 years of study and the final prevalence of nontoxic genera in the reservoir is an evidence of water quality improvement in response to the management techniques implemented in the reservoir basin. 相似文献
997.
Jean-Philippe Boussemart Hervé Leleu Oluwaseun Ojo 《Environmental Modeling and Assessment》2013,18(5):523-532
The purpose of this paper is to analyse the spread of pesticide practices with respect to crop production (wheat, barley, and rapeseed) in French agriculture and to evaluate the potential pesticide reductions for cost-efficient farmers. This is made possible by conducting a double-step analysis based on non-parametric robust technology. First, from a panel data of 650 farms over a 12-year period located in the French department of Meuse, we selected the cost-efficient farms thanks to a robust free disposal hull (RFDH) technology. A second RFDH frontier analysis was run only on the selected cost-efficient farms thus enabling us to reveal the units which minimize the pesticide use per hectare while maintaining constant yields. Therefore, all the different total cost-efficient practices among farmers were evaluated in terms of pesticide per hectare and the minimum uses were selected. Our main conclusion is that the pesticide reductions per hectare for the cost-efficient farms could reach 24 %. 相似文献
998.
José E. Celis Winfred Espejo Daniel González-Acuña Solange Jara Ricardo Barra 《Environmental monitoring and assessment》2014,186(3):1815-1824
To add data on trace metal contamination of Humboldt penguins in the South Pacific, levels of trace metals (As, Hg, Pb, Cu, Zn, and Cd) and porphyrins (copro-, uro-, and proto-) in excreta of Humboldt penguins that inhabit some important nesting sites on the northern coast of Chile were determined. Fresh excreta were collected on Pan de Azúcar Island, Chañaral Island, and Cachagua Island, from December 2011 to January 2012. Concentration of metals was determined by flame atomic absorption spectrophotometry, whereas porphyrins levels were measured by fluorimetric analysis. Concentrations (dry weight) of Cu (199.67 μg g?1), As (7.85 μg g?1), and Pb (12.78 μg g?1) were higher (p?≤?0.05) in Cachagua Island. Colonies from Pan de Azúcar Island showed the highest levels of Hg (0.76 μg g?1), Cd (47.70 μg g?1), and Zn (487.10 μg g?1). Samples from Cachagua Island showed the highest (p?≤?0.05) levels of copro- (2.16 nmol g?1), uro- (2.20 nmol g?1), and protoporphyrins (2.23 nmol g?1). There was a positive correlation between the metals As, Pb, and Cu with uro-, copro-, and protoporphyrins. The results indicated that penguin colonies from Cachagua Island are more exposed to metal contamination than penguin colonies from Pan de Azúcar and Chañaral Islands, thus being more likely to develop certain diseases caused by contamination with metals. Considering biomagnification, the metals detected in the excreta of Humboldt penguins can be a source of contamination from marine environments to terrestrial ecosystems, which could also affect other living organisms. 相似文献
999.
Beniamino Gioli Maria F. Carfora Vincenzo Magliulo Maria C. Metallo Attilio A. Poli Piero Toscano Franco Miglietta 《Environmental monitoring and assessment》2014,186(4):2053-2066
Aircraft measurements were used to estimate the CO2 emission rates of the city of Rome, assessed against high-resolution inventorial data. Three experimental flights were made, composed of vertical soundings to measure Planetary Boundary Layer (PBL) properties, and circular horizontal transects at various altitudes around the city area. City level emissions and associated uncertainties were computed by means of mass budgeting techniques, obtaining a positive net CO2 flux of 14.7?±?4.5, 2.5?±?1.2, and 10.3?±?1.2 μmol m?2 s?1 for the three flights. Inventorial CO2 fluxes at the time of flights were computed by means of spatial and temporal disaggregation of the gross emission inventory, at 10.9?±?2.5, 9.6?±?1.3, and 17.4?±?9.6 μmol m?2 s?1. The largest differences between the two dataset are associated with a greater variability of wind speed and direction in the boundary layer during measurements. Uncertainty partitioned into components related to horizontal boundary flows and top surface flow, revealed that the latter dominates total uncertainty in the presence of a wide variability of CO2 concentration in the free troposphere (up to 7 ppm), while it is a minor term with uniform tropospheric concentrations in the study area (within 2 ppm). Overall, we demonstrate how small aircraft may provide city level emission measurements that may integrate and validate emission inventories. Optimal atmospheric conditions and measurement strategies for the deployment of aircraft experimental flights are finally discussed. 相似文献
1000.
Gbénonchi Mawussi Rômulo P. Scorza Júnior Ekwe L. Dossa Koffi-Kouma Akouété Alaté 《Environmental monitoring and assessment》2014,186(11):7379-7385
Some common organochlorine, organophosphorus and pyrethroid insecticides were analysed in agricultural soil samples (n?=?35) and surface water and groundwater samples (n?=?25) collected from coastal areas of vegetable production in Togo. Analytical methods included solvent extraction of the insecticide residues and their subsequent quantification using GC-ECD. δ-HCH, heptachlor epoxide, 4,4-DDE, endosulphan (α, β and sulphate), lambda-cyalothrin and chlorpyrifos were found in the soil samples with concentrations that varied from non-detectable (ND) to 26.93 μg kg?1 dry weight. For water samples, heptachlor epoxide, 2,4-DDD, 4,4-DDD, 4,4-DDE and endosulphan (α, β, and sulphate) were found at contamination levels that varied from ND to 0.116 μg L?1. The concentration of insecticide residues detected in the water samples was below the limits set by the World Health Organization (WHO) and also by the European Union (EU), with the exception of the concentration of endosulphan sulphate at the Aného site, which was 0.116 μg L?1. 相似文献