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31.
Davidova  R.  Vasilev  V.  Boycheva  M.  Bakalova  J.  Ali  N. 《Russian Journal of Ecology》2019,50(2):200-207

The dynamics of nest-dwelling mites from the nests of the great tit in the protected area of Kamchia Mountain in Northeastern Bulgaria was investigated. The mite fauna inhabiting the nests of great tit differs significantly in terms of the degree of infestation, species richness, abundance and structure of communities in study years. There are statistically significant differences in the specimens’ number between 2014 and the other years 2012, 2013 and 2015. The mite species such as Dermanyssus gallinae, Androlaelaps casalis and Ornithonyssus sylviarum demonstrated significant changes in the abundance over the study years. A relation between the abundance of a species and the species diversity in the nests was not registered. Comparison of the annual dynamics of mites in the nests of great tit and the nests of semi-collared flycatcher for the same period of time and for the same environment, showed similarities—a significant fluctuation in the abundance of mites over the years and differences—in the species richness. Regarding the structure of the communities, both similarities and differences were recorded.

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This study was meant to determine environmental aspects of hospital waste management scenarios using a life cycle analysis approach. The survey for this study was conducted at the largest hospital in a major city of Pakistan. The hospital was thoroughly analyzed from November 2014 to January 2015 to quantify its wastes by category. The functional unit of the study was selected as 1 tonne of disposable solid hospital waste. System boundaries included transportation of hospital solid waste and its treatment and disposal by landfilling, incineration, composting, and material recycling methods. These methods were evaluated based on their greenhouse gas emissions. Landfilling and incineration turned out to be the worst final disposal alternatives, whereas composting and material recovery displayed savings in emissions. An integrated system (composting, incineration, and material recycling) was found as the best solution among the evaluated scenarios. This study can be used by policymakers for the formulation of an integrated hospital waste management plan.

Implications: This study deals with environmental aspects of hospital waste management scenarios. It is an increasing area of concern in many developing and resource-constrained countries of the world. The life cycle analysis (LCA) approach is a useful tool for estimation of greenhouse gas emissions from different waste management activities. There is a shortage of information in existing literature regarding LCA of hospital wastes. To the best knowledge of the authors this work is the first attempt at quantifying the environmental footprint of hospital waste in Pakistan.  相似文献   

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In the present paper, the optimum design of a PV system used to operate a water pumping system was determined for Oman. The system design focused on the environmental conditions of Sohar city. The implementation and measurement of the designed system are presented to prove the effectiveness of the proposed system. The results show that the system can provide the required power at peak hours, leading to a substantial reduction in the sizing of the PV system. Consequently, the investment capital costs 2400 USD, and the cost of energy is equal to 0.309 USD/kWh. Furthermore, the results indicate that the system annual yield factor is 2024.66 kWh/kWp and that the capacity factor is 23.05 %, which is encouraging since the latter is typically 21 %. The system capital cost and the cost of energy are worth comparing to a diesel generator. A comparison is made between the proposed system and several others in the literature. The comparison indicated that the system cost of energy is promising.  相似文献   
36.
Poisonous lead (Pb), among heavy metals, is a potential pollutant that readily accumulates in soils and thus adversely affects physiological processes in plants. We have evaluated how exogenous H2S affects cotton plant physiological attributes and Pb uptake under Pb stress thereby understanding the role of H2S in physiological processes in plants. Two concentrations (0 and 200 μM) of H2S donor sodium hydrosulfide (NaHS) were experimented on cotton plants under Pb stress (0, 50, and 100 μM). Results have shown that Pb stress decreased plant growth, chlorophyll contents, SPAD value, photosynthesis, antioxidant activity. On the other hand, Pb stress increased the level of malondialdehyde (MDA), electrolyte leakage (EL), and production of H2O2 and uptake of Pb contents in all three parts of plant, viz. root, stem, and leaf. Application of H2S slightly increased plant growth, chlorophyll contents, SPAD value, photosynthesis, and antioxidant activity as compared to control. Hydrogen sulfide supply alleviated the toxic effects of lead on plant growth, chlorophyll contents, SPAD value, photosynthesis, and antioxidant activity in cotton plants. Hydrogen sulfide also reduced MDA, EL, and production of H2O2 and endogenous Pb levels in the three mentioned plant parts. On the basis of our results, we conclude that H2S has promotive effects which could improve plant survival under Pb stress.  相似文献   
37.
The building sector has been regarded as a potential sector where there is large capacity to reduce the climate change effect. This study has proposed solutions to mitigate environmental impacts and achieve low CO2 emission from residential sector. Therefore, full life cycle assessment (LCA) has been run to assess the CO2 emission and its effect on the atmosphere and climate change. Based on the result, timber scheme is the best choice due to releasing less CO2 emissions to the atmosphere. However, house builders in Malaysia have almost completely neglected timber as a building material, with timber use as building components reduced to 5%. In this study, LCA Software was used to assess CO2 emissions from different wall construction. The alternative building scheme has been made by reinforce steel stud, wooden beam and timber wall (S8) to improve the scheme deficiency while releasing less CO2 emissions compared to other schemes. Therefore, S8 has a decreased CO2 effect by 85% less than precast concrete frame and 90% less than brick over their lifetime. (S8) increased the load bearing compared to conventional timber beam. Thus, new scheme S8 could be replaced by current scheme and promote more adjustable scheme for Malaysian housing.  相似文献   
38.
The Alemaya district (Eastern Ethiopian highlands) is characterized by undulating physiographic features with arid, semi-arid, and humid climatic conditions. This study evaluated socio-environmental changes in land use and land cover during 1985–2011. Screen digitization on remotely sensed data (i.e., Landsat images from 1985 to 2011) was performed to produce 10 classes of land use and land cover. Then, final land-use maps were prepared using a geographic information system following field verification and accuracy assessment. The drying of water bodies, including the prominent lakes Alemaya, Adele, and Tinike, had been the most important environmental change observed. Degraded land, marsh, perennial cropland, and residential areas increased by 37, 438, 42, and 190 %, respectively, whereas grassland, plantation, shrubland, and temporal cropland decreased by 64, 11, 63, and 29 %, respectively. The increase in land degradation (+37 %), the other major observed problem, has made large areas unsuitable for agriculture and has reduced crop productivity. These land-use and land-cover changes have affected both the environment and the livelihoods of local residents; especially the issue related to land degradation requires urgent attention.  相似文献   
39.
Environmental Science and Pollution Research - Copper (Cu) is an important trace element required for several biological processes. The use of copper is increasing gradually in several...  相似文献   
40.
Environmental Science and Pollution Research - Chromium (Cr) is a biologically non-essential, carcinogenic and toxic heavy metal. The cultivation of Cr-tolerant genotypes seems the most favorable...  相似文献   
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