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191.
Environmental Science and Pollution Research - This study evaluates the characteristics of water along the Swat River, Northern Pakistan. For this purpose, water samples (n = 30) were...  相似文献   
192.
The pivot point of delta in Tarbela dam has reached at about 10.6 km from the dam face which may result in blocking of tunnels. Tarbela delta was modeled from 1979 to 2060 using hec-6 model. Initially, the model was calibrated for year 1999 and validated for years 2000, 2001, 2002, and 2006 by involving the data of sediment concentration, reservoir cross sections (73 range lines), elevation-area capacity curves, and inflows and outflows from the reservoir. Then, the model was used to generate future scenarios, i.e., run-1, run-2, and run-3 with pool levels; 428, 442, and 457 m, respectively, till 2060. Results of run-1 and run-2 showed advancement to choke the tunnels by 2010 and 2030, respectively. Finally, in run-3, the advancement was further delayed showing that tunnels 1 and 2 will be choked by year 2050 and pivot point will reach at 6.4 km from the dam face.  相似文献   
193.
Environmental Science and Pollution Research - Since the dawn of century, tons of keratin bio-waste is generated by the poultry industry annually, and they end up causing environmental havoc....  相似文献   
194.

Financial development is important for the growth of a country which indirectly affects the environment adversely through industrialization. However, in the presence of strong institutions, this adverse effect can be reduced. The main concern of the present study is to estimate the relation between CO2 and financial development (FD) in the presence of economic institutions as an interactive term. A sample of 101 countries has been selected for econometric analysis for the period from 1995 to 2017. The cross-section dependence test statistics for dependency, CIPS and CADF for panel unit root test, Westerlund test to ascertain the long-run affiliations, and FMOLS to extract the long-run coefficients have been applied. Dumitrescu and Hurlin test is also employed to know about the causal nature of the panel series. The findings show that financial development has a positive relationship with CO2. However, after inclusion of economic intuitions, the adverse impact of financial development on the environment is reduced. The study also confirms the presence of environmental Kuznets curve in the context of income and financial development. The findings imply that financial development can help to improve environment quality if it is accompanied with strong institutional framework such as assurance of property rights, government integrity, and liberalization in financial sector.

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195.
Adult male Swiss albino mice were administered ip. suspension solution of cypermethrin in 0.15% DMSO at the doses of 30 mg, 60 mg and 90 mg/kg b. wt. daily for 5 days. Another group of animals was injected cyclophosphamide ip. (60 mg/kg b. wt.) in similar manner which served as positive control. Effect of cypermethrin on body and testes weight and sperm head morphology was studied. Clastogenic potential of cypermethrin was studied by using modified Allium test. The cytological changes were studied in the root tip cells of Allium cepa after 3 days treatment with three different concentration of cypermethrin (0.1, 1.0 and 10.0 microg/ml). The results revealed that body weight gain was considerably reduced in higher dose groups, but the testicular weight did not change significantly in any of the cypermethrin treated groups. However, a significant elevation in the number of abnormal shape of sperm head was noticed in higher dose groups as compared to control. It was observed that the abnormality in the shape of sperm head was dose-dependent. The cytological changes in the root tip cells of Allium cepa indicated that cypermethrin is having toxic effects on the root tip cells in the form of stickiness of chromosomes and also affect the mitotic activity. This study suggest that cypermethrin may have the potential to induce adverse effects on sperm head shape morphology of mouse as well as clastogenic effects on root tip cells of Allium cepa.  相似文献   
196.
Agriculture is one of the major sources of greenhouse gas (GHG) emission. It accounts for approximately 15% of the total global anthropogenic emissions of GHGs. Emissions could be twice as much if indirect emissions are also taken into the consideration. However, unlike other high emitting sectors such as transport or energy, agriculture is potentially a significant carbon “sink”. It has high technical potential as a carbon sink and if tapped, can substantially enhance global sequestration efforts. The technical potential, however, may not translate into actual GHG reduction because of the capital assets and institutional constraints faced by the smallholder farmers in the developing countries. In this paper we develop a capital assets based framework of physical, financial, social, human and natural barriers to agricultural carbon mitigation initiatives and through analysis of current initiatives, we set out policy based options to reduce each of these barriers. Fundamentally, barrier removal will entail designing agricultural carbon mitigation initiatives in collaboration with farmer communities, through strengthening local institutions, understanding land tenure and natural resource cultures, ensuring legitimacy and equity in payments and fast tracking training and information. We provide a framework that simultaneously aids the dual objectives of alleviating poverty in the poor farming communities of developing countries and lowering global greenhouse gas emissions.  相似文献   
197.
Spatial variations in total suspended particulate matter (TSP) were investigated for distribution of metals and particle size fractions in the urban and rural atmosphere of Islamabad, Pakistan. The metals Na, K, Fe, Mn, Pb, Cd, Cr, Zn, Ni and Co, and the particle fractions <2.5, 2.5-10, 10-100 and >100 microm were included in the study. TSP samples were trapped on glass fibre filters using high volume samplers and quantification of metals was done using Atomic Absorption Spectrometry employing HNO(3) based wet digestion. At the urban site, Na was dominant at 2.384 microg/m(3) followed by K, Fe and Zn with 0.778, 0.667 and 0.567 microg/m(3) as mean concentrations, respectively. The metal levels for the rural site ranged from 0.002 microg/m(3) for Cd to 1.077 microg/m(3) for Na. However, compared with the urban site, mean Pb concentration showed an almost two-fold enhancement, i.e., 0.163 Vs. 0.327 microg/m(3). Metals and particle size source identification was done using Principal Component Analysis and Cluster Analysis. Five sources were traced out for the urban site: industrial, soil, automobile emissions, metallurgical industries and excavation activities. For the rural site, four sources were recorded: agricultural, automotive emissions, excavation activities and metallurgical units. Collectively, for both the sites, PM(10-100) emerged as a major contributor to TSP, followed by PM(2.5-10), PM(<2.5) and PM(>100) in that order. The metals showed in general positive relationship with fine particulate fractions (PM(2.5-10), PM(<2.5)), and negative correlation with coarse fractions (PM(10-100), PM(>100)). Comparison with the corresponding data from various Asian sites revealed that the levels of Na, K, Fe, Mn, Co and Ni for the present study were lower than those reported for grossly polluted cities of the world.  相似文献   
198.
Environmental Science and Pollution Research - Poor agricultural communities are particularly more disruptive to changes in climate. In southeast Asian countries, Pakistan is extremely vulnerable...  相似文献   
199.
Cotton (Gossypium hirustum L.) is grown globally as a major source of natural fiber. Nitrogen (N) management is cumbersome in cotton production systems; it has more impacts on yield, maturity, and lint quality of a cotton crop than other primary plant nutrient. Application and production of N fertilizers consume large amounts of energy, and excess application can cause environmental concerns, i.e., nitrate in ground water, and the production of nitrous oxide a highly potent greenhouse gas (GHG) to the atmosphere, which is a global concern. Therefore, improving nitrogen use efficiency (NUE) of cotton plant is critical in this context. Slow-release fertilizers (e.g., polymer-coated urea) have the potential to increase cotton yield and reduce environmental pollution due to more efficient use of nutrients. Limited literature is available on the mitigation of GHG emissions for cotton production. Therefore, this review focuses on the role of N fertilization, in cotton growth and GHG emission management strategies, and will assess, justify, and organize the researchable priorities. Nitrate and ammonium nitrogen are essential nutrients for successful crop production. Ammonia (NH3) is a central intermediate in plant N metabolism. NH3 is assimilated in cotton by the mediation of glutamine synthetase, glutamine (z-) oxoglutarate amino-transferase enzyme systems in two steps: the first step requires adenosine triphosphate (ATP) to add NH3 to glutamate to form glutamine (Gln), and the second step transfers the NH3 from glutamine (Gln) to α-ketoglutarate to form two glutamates. Once NH3 has been incorporated into glutamate, it can be transferred to other carbon skeletons by various transaminases to form additional amino acids. The glutamate and glutamine formed can rapidly be used for the synthesis of low-molecular-weight organic N compounds (LMWONCs) such as amides, amino acids, ureides, amines, and peptides that are further synthesized into high-molecular-weight organic N compounds (HMWONCs) such as proteins and nucleic acids.  相似文献   
200.

Climate change in the global perspective has increased the occurrence of natural disasters, which subsequently decreased agricultural production and intensified the issue of food security. Developing countries, such as Pakistan, are facing severe food security issues, where most of the population still experiences poverty and hunger in their daily lives. Flood disasters ruin valuable land, cause agricultural production losses, and interrupt livelihood routines as expected household livelihood becomes more vulnerable. This research work focused on investigating the flood hazards vulnerability and risk of food security in the Bait community flood-prone areas of Punjab, Pakistan, with a broader aspect in contrast to previous research work. A constructed food security index composed of several IPCC and FAO factors with correlated dimensions of food security was used for the empirical estimation in this study. A composite food security index was developed through polychoric principal component analysis. To estimate the influence on the overall food security condition in the study area, a food security index was regressed on various independent variables. Estimates of the study indicated that three-fourths of household respondents in the study area are confronted with the issue of food security with changeable scale. Financing schemes, physical assets, and family type illustrated the positive influence on respondents’ food security level, whereas respondents suffering property losses owing to floods had a negative influence. The study findings suggested integrated strategies must be adopted to effectively deal with issues of food security in the scenario of increasing severity of flood disasters. Policymakers and disaster-concerned institutions need to develop disaster risk mitigation strategies by constructing new water reserves and clearing river encroachments to deal with flood disasters. Agricultural research and development authorities need to provide climate friendly seed varieties and promote particular food crops for flood prone areas to ensure food security and reduce livelihood vulnerability, specifically for the flood-prone communities.

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