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The use of wastewater in livestock production and its socioeconomic and welfare implications Полный текст
2017
Elahi, Ehsan | Abid, Mohamed | Zhang, Liqin | Alugongo, Gibson Maswayi
Although epidemiological studies have found a significant amount of toxins in surface water, a complex link between animals’ access to wastewater and associated animal and human welfare losses needs to be explored. The scarcity of safe water has put stress on the utilization of wastewater for crops and livestock production. The access of animals to wastewater is related to the emergence of dangerous animal’s diseases, hampering productivity, increasing economic losses, and risking human health along the food chain. This review explores use of wastewater for agriculture, epidemiological evidence of microbial contamination in wastewater, and animal and human welfare disruption due to the use of wastewater for crop and livestock production. More specifically, the review delves into animals exposure to wastewater for bathing, drinking, or grazing on a pasture irrigated with contaminated water and related animal and human welfare losses. We included some scientific articles and reviews published from 1970 to 2017 to support our rational discussions. The selected articles dealt exclusively with animals direct access to wastewater via bathing and indirect access via grazing on pasture irrigated with contaminated wastewater and their implication for animal and human welfare losses. The study also identified that some policy options such as wastewater treatments, constructing wastewater stabilization ponds, controlling animal access to wastewater, and dissemination of necessary information to ultimate consumers related to the source of agricultural produce and wastewater use in animal and crop production are required to protect the human and animal health and welfare.
Показать больше [+] Меньше [-]Economic impacts of calving season and parity on reproduction and production traits of buffaloes in the sub-tropics Полный текст
2017
Hassan, Fardos A. M. | Ali, Mohamed A. | El-Tarabany, Mahmoud S.
In order to enhance the profitability of dairy buffaloes, it is necessary to develop an understanding of the factors affecting their reproduction and milk production ability. Thus, the objective of this study was to elucidate the economic impacts of calving season and parity on reproduction and production indices of Egyptian dairy buffaloes (1180) reared under subtropical environmental conditions. Buffaloes calving in the autumn season had lesser days open, calving interval, and service per conception (108.25 days, 414.16 days, and 1.67, respectively), while spring calvers showed the greater calculations (210.27 days, 522.82 days, and 2.39, respectively). The buffaloes calving for the first time had the longest days open, calving interval, and number of services per conception among different parities (176.21 days, 490.05 days, and 2.18, respectively), then decreased thereafter. Furthermore, buffaloes calving in the winter season had the significantly highest total milk yield, milk revenue, total revenue, profit, and profit/cost ratio (1981.4 kg, 1769.1 $, 2019.5 $, 662.9 $, and 0.49, respectively) in comparison with other seasons. The total milk yield, lactation period, profit, and profit/cost ratio were increased to reach the peak values in the fourth parity (2051.5 kg, 252.44 days, 674.8 $, and 0.48, respectively), then decreased thereafter. In conclusion, buffaloes at the fourth parity and those calving in the winter season had the best milk yield, milk revenue, total revenue, and profit/cost ratio. Therefore, breeders must pay more attention to calving season and parity as they play an important role in the farm profitability and productivity and should counteract the adverse effects of periodical and seasonal changes. It is recommended to make estrus synchronization for more calvings in the winter season. Finally, choose the best lifetime for keeping the animal in production.
Показать больше [+] Меньше [-]Spatial variation of air quality index and urban driving factors linkages: evidence from Chinese cities Полный текст
2017
Pu, Haixia | Luo, Kunli | Wang, Bin | Wang, Shaobin | Kang, Shun
Daily air quality index (AQI) of 161 Chinese cities obtained from the Ministry of Environmental Protection of China in 2015 is conducted. In this study, to better explore spatial distribution and regional characteristic of AQI, global and local spatial autocorrelation is utilized. Pearson’s correlation is introduced to determine the influence of single urban indicator on AQI value. Meanwhile, multiple linear stepwise regression is chosen to estimate quantitatively the most influential urban indicators on AQI. The spatial autocorrelation analysis indicates that the AQI value of Chinese 161 cities shows a spatial dependency. Higher AQI is mainly located in north and northwest regions, whereas low AQI is concentrated in the south and the Qinghai-Tibet regions. The low AQI and high AQI values in China both exhibit relative immobility through seasonal variation. The influence degree of three adverse urban driving factors on AQI value is ranked from high to low: coal consumption of manufacturing > building area > coal consumption of the power industry. It is worth noting that the risk of exposed population to poor quality is greater in the northern region than in other regions. The results of the study provide a reference for the formulation of urban policy and improvement of air quality in China.
Показать больше [+] Меньше [-]Diversity and activity patterns of sympatric animals among four types of forest habitat in Guanyinshan Nature Reserve in the Qinling Mountains, China Полный текст
2017
Liu, Xuehua | Wu, Pengfeng | Shao, Xiaoming | Songer, Melissa | Cai, Qiong | He, Xiangbo | Zhu, Yun
Environmental heterogeneity contributes to various habitats and may influence the diversity and activity patterns of wildlife among habitats. We used camera traps to assess wildlife habitat use in Guanyinshan Nature Reserve from 2009 to 2012. We focused on four types of habitat including open areas with gentle slope (<15°) (Type1), low elevation areas (about 1500–1700 m) with high bamboo coverage (Type2), high elevation areas (about 2100–2300 m) with high canopy coverage (Type3), and wildlife migration passages (Type4). We analyzed the differences in species richness, relative abundance index (RAI), species diversity, and animals’ activity pattern among habitats. Total six species were analyzed on activity pattern, which are Takin (Budorcas taxicolor), tufted deer (Elaphodus cephalophus), Himalayan goral (Naemorhedus goral), wild boar (Sus scrofa), golden pheasant (Chrysolophus pictus), and porcupine (Hystrix hodgsoni). The results are (1) that there were significant differences in richness and RAIₜ among habitats; (2) Type4 habitat had the highest richness and RAIₜ while Type2 had the highest species diversity; giant pandas were found in these two habitats; (3) there were significant differences in species’ activity during daytime and nighttime; and (4) differences appeared in habitat preference of the most abundant species. Takin and tufted deer preferred Type1, Himalayan goral preferred Type2, and golden pheasant preferred Type3. Type4 habitat was used by most animals. All these revealed that habitat heterogeneity plays an important role in species diversity and the importance for conservation.
Показать больше [+] Меньше [-]Air protection programmes in Poland in the context of the low emission Полный текст
2017
Adamczyk, Janusz | Piwowar, Arkadiusz | Dzikuć, Maciej
The protection of the air against pollutants from individual boiler plants is a big challenge in Poland. It results mainly from the preference for coal, the national energy carrier, the use of old low-efficiency boilers and the location of Poland in a temperate climate where the heating period lasts at least 5 months. This article presents a wide range of activities aimed at the reduction of the environmental impact of the emissions of pollutants from individual heat sources—the so-called low emission. The article presents the extent of the national legislation resulting from the European Union regulations. It discusses the assumptions of the air protection programmes (APPs) and the low emission reduction programmes (LERPs). The assumptions mentioned above are analysed as part of a life cycle assessment (LCA) analysis and a multi-criterion analysis. An important result of these analyses (in the Polish conditions) is the conclusion that a boiler fired with large pieces of wood is an optimal solution from the economic and ecological points of view. The article proposes systemic, organisational and legislative solutions whose implementation could contribute to raising the effectiveness of the protection of the atmosphere.
Показать больше [+] Меньше [-]Heavy metal contamination in sand and sediments near to disposal site of reject brine from desalination plant, Arabian Gulf: Assessment of environmental pollution Полный текст
2017
Alshahri, Fatimh
Accumulation of heavy metals in environment may cause series potential risk in the living system. This study was carried out to investigate heavy metal contamination in sand samples and sediments along the beach near to disposal site of reject brine from Alkhobar desalination plant, which is one of the oldest and largest reverse osmosis desalination plants in eastern Saudi Arabia, Arabian Gulf. Fourteen heavy metals (U, Ca, Fe, Al, Ti, Sr, Rb, Ni, Pb, Cd, Cr, Cu, As, and Zr) were measured using gamma-ray spectrometry, atomic absorption spectrometer (AAS) and energy dispersive X-ray fluorescence spectrometer (EDX). The obtained data revealed that the concentrations of these metals were higher than the values in sediment and soil for other studies in Arabian Gulf. Furthermore, the mean values of Fe, Mn, Cr, Cu, As, Sr, and Zr concentrations in sand and sediments were higher than the geochemical background values in shale. The contamination factor (CF), modified degree of contamination (mCd) and pollution load index (PLI) were assessed. According to contamination factors (CF > 1), the results showed elevated levels of Cu, Cr, Mn, Zr, and As in all samples. The highest value of contamination factor was found for As. Based on PLI (PLI > 1), the values of all sampling sites indicate a localized pollution in the study area. Current study could be useful as baseline data for heavy metals in sand and sediments nearby a desalination plant.
Показать больше [+] Меньше [-]The effect of anthropogenic pressure shown by microbiological and chemical water quality indicators on the main rivers of Podhale, southern Poland Полный текст
2017
Lenart-Boroń, Anna | Wolanin, Anna | Jelonkiewicz, Ewelina | Żelazny, Mirosław
The effect of anthropogenic pressure shown by microbiological and chemical water quality indicators on the main rivers of Podhale, southern Poland Полный текст
2017
Lenart-Boroń, Anna | Wolanin, Anna | Jelonkiewicz, Ewelina | Żelazny, Mirosław
This study was aimed to determine the spatial variation in anthropogenic pressure exerted on surface water in the Podhale region (southern Poland), which is one of the most popular tourist destinations in Poland. The assessment was based on the dynamics and relationships between microbiological and chemical indicators of water quality throughout the major rivers of this region—Dunajec, Czarny Dunajec, Biały Dunajec, and Białka. Another aim was to assess the effect of land use on the quality of water in the studied rivers. The study was conducted over 1 year at 21 sampling sites distributed from the uppermost sections of rivers in the Tatra National Park through main tourist resorts until mouths of the considered rivers to the Czorsztyńskie Lake. Microbiological analysis comprised the prevalence of total and fecal types of coliforms and Escherichia coli, mesophilic, and psychrophilic bacteria. Chemical assays determined the concentrations of Na⁺, K⁺, NH₄ ⁺, Cl⁻, NO₃ ⁻, and PO₄ ³⁻. Temperature, electrical conductivity, and pH were measured onsite. It was demonstrated that there is a significant relationship between the predominant types of land use within individual catchments, which results in evident differences in the pollution of waters between the catchments. The results showed that increased share of built-up areas and arable land results in significant deterioration of water quality. Thus, waters of Czarny Dunajec were the cleanest, while Biały Dunajec was the most heavily contaminated. Also, spatial diversity in water quality was shown—the cleanest waters were sampled in the Tatra National Park and the pollution increased with the course of rivers. Point sources of pollution such as effluents from treatment plants or discharge of untreated sewage from households proved to be more important than non-point sources, such as surface runoff. Moreover, the important role of the Czorsztyńskie Lake in the purification of water was demonstrated.
Показать больше [+] Меньше [-]The effect of anthropogenic pressure shown by microbiological and chemical water quality indicators on the main rivers of Podhale, southern Poland Полный текст
Anna Lenart-Boroń | Anna Wolanin | Ewelina Jelonkiewicz | Mirosław Żelazny
This study was aimed to determine the spatial variation in anthropogenic pressure exerted on surface water in the Podhale region (southern Poland), which is one of the most popular tourist destinations in Poland. The assessment was based on the dynamics and relationships between microbiological and chemical indicators of water quality throughout the major rivers of this region—Dunajec, Czarny Dunajec, Biały Dunajec, and Białka. Another aim was to assess the effect of land use on the quality of water in the studied rivers. The study was conducted over 1 year at 21 sampling sites distributed from the uppermost sections of rivers in the Tatra National Park through main tourist resorts until mouths of the considered rivers to the Czorsztyńskie Lake. Microbiological analysis comprised the prevalence of total and fecal types of coliforms and Escherichia coli, mesophilic, and psychrophilic bacteria. Chemical assays determined the concentrations of Na+, K+, NH4+, Cl−, NO3−, and PO43−. Temperature, electrical conductivity, and pH were measured onsite. It was demonstrated that there is a significant relationship between the predominant types of land use within individual catchments, which results in evident differences in the pollution of waters between the catchments. The results showed that increased share of built-up areas and arable land results in significant deterioration of water quality. Thus, waters of Czarny Dunajec were the cleanest, while Biały Dunajec was the most heavily contaminated. Also, spatial diversity in water quality was shown—the cleanest waters were sampled in the Tatra National Park and the pollution increased with the course of rivers. Point sources of pollution such as effluents from treatment plants or discharge of untreated sewage from households proved to be more important than non-point sources, such as surface runoff. Moreover, the important role of the Czorsztyńskie Lake in the purification of water was demonstrated. | Coliforms; E. coli; Water quality; Podhale; Anthropopressure | 30 | 12938-12948 | 14
Показать больше [+] Меньше [-]Foam-forming bacteria in activated sludge effectively reduced by rotifers in laboratory- and real-scale wastewater treatment plant experiments Полный текст
2017
Pajdak-Stós, Agnieszka | Kocerba-Soroka, Wioleta | Fyda, Janusz | Sobczyk, Mateusz | Fiałkowska, Edyta
Lecane inermis rotifers were shown to diminish sludge bulking due to their ability to ingest the filamentous bacteria in activated sludge. To determine if rotifers are also able to control branched actinomycetes, we investigated three other Lecane species (Monogononta). In a week-long experiment, only Lecane tenuiseta significantly reduced the density of Microthrix parvicella and Type 0092 filaments, but in a 2-week experiment, actinomycetes were significantly reduced by most of the tested monogonont rotifers: L. inermis, Lecane decipiens and Lecane pyriformis. Rotifers L. inermis originating from the mass culture were artificially introduced into real-scale wastewater treatment plant (WWTP) in two series. The WWTP was monitored for 1 year. Rotifer inoculation resulted in diminishing of M. parvicella and actinomycete abundance. The experiments showed that different species of rotifers vary in their effectiveness at limiting various types of filamentous organisms. This is the first report demonstrating that one of the most troublesome bacteria, branched actinomycetes, which cause heavy foaming in bioreactors, can be controlled by rotifers. Knowledge of the consumers of filamentous bacteria that inhabit activated sludge could help WWTP operators overcome bulking and foaming through environmentally friendly methods.
Показать больше [+] Меньше [-]The potential DNA toxic changes among workers exposed to antimony trioxide Полный текст
2017
El Shanawany, Safaa | Foda, Nermine | Hashad, Doaa I. | Salama, Naglaa | Sobh, Zahraa
Occupational exposure to antimony has gained much interest when specific toxic effects were noticed among workers processing antimony. Thus, the aim of the present work was to investigate the potential DNA oxidative damage occurring among Egyptian workers occupationally exposed to antimony trioxide. The study was conducted on 25 subjects exposed to antimony trioxide while working in the polymerization process of polyester in Misrayon and Polyester Fiber Company, KafrEldawwar, Beheira, Egypt. Urinary antimony levels were assessed using inductive coupled plasma–optical emission spectrometry (ICP-OES) and considered as a biological exposure index. DNA damage and total oxidant capacity (TOC) were assessed using ELISA. DNA damage was detected in the form of increased apurinic/apyrimidinic (AP) sites among antimony trioxide-exposed workers compared to control subjects, but it could not be explained by oxidative mechanisms due to lack of significant correlation between DNA damage and measured TOC. Antimony trioxide might have a genotoxic impact on occupationally exposed workers which could not be attributed to oxidative stress in the studied cases.
Показать больше [+] Меньше [-]Scenario-based analysis of traffic-related PM2.5 concentration: Lisbon case study Полный текст
2017
Faria, Marta V. | Duarte, Gonçalo O. | Baptista, Patrícia C. | Farias, Tiago L.
Air quality in urban centers constitutes a challenge ahead for most cities. For this reason, the objective of this research work was to evaluate the impacts of changing traffic-related parameters on particulate matter (PM) concentration for several hierarchical street levels using real-world data for the city of Lisbon, Portugal. For that purpose, 2014 data regarding meteorological conditions, traffic volumes, typical vehicle speed, and a vehicle representative of the fleet was used in an air quality dispersion model (CALINE4). The available data allowed building a baseline case for several streets that are representative of the traffic circulation conditions in Lisbon, which was compared with different scenarios: hypothetical introduction of a cordon toll (S1.1 to S1.4) and the implementation of a low emission zone (S2.1 and 2.2). The results indicate that reductions on PM₂.₅ concentrations from 5 to 42 % may be obtained from the implementation of the scenarios. Overall, this study demonstrates that modeling tools based on real-world data can provide a good approach to study urban policies regarding traffic-related PM exposure. Additionally, implementation of such measures requires an integrated strategy that enables proper enforcement and monitoring, as well as an adequate management of traffic flows between the implementation boundaries.
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