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81.
Environment, Development and Sustainability - This study explores the adverse impact of air pollution, caused by emissions from brick kilns, on the children’s cognitive ability and physical...  相似文献   
82.
Segara Anakan is a mangrove-fringed lagoon in Java, Indonesia, which is affected by human activities in the lagoon and its hinterland. Nutrient and sediment input from the Citanduy River which drains an agriculture-dominated hinterland is thought to be an important factor for ecosystem degradation. From dry and rainy season investigations of dissolved inorganic nutrients between May 2004 and August 2006 we infer that the nutrient inventory of Segara Anakan is controlled by a complex mixture of anthropogenic and natural sources and processes. Maximum inputs into the western lagoon were supplied by the Citanduy during the rainy season while tidal exchange with the Indian Ocean dominated in the eastern lagoon with little freshwater input. During the dry season recycling in mangroves appeared to be an additional source of nutrients to the lagoon. Despite an extremely high population density and intensive agriculture in the hinterland nutrient pollution and eutrophication in the lagoon were low to moderate on a global scale. It is probably due to the short residence time of water in the shallow lagoon which indicates that major part of the land-derived nutrient input is rapidly exported to the sea. Although Segara Anakan is a highly perturbed system for decades, it appears that still natural processes exert major control on the nutrient inventory of the lagoon.  相似文献   
83.
This study focuses on the Quaternary stratigraphy, sediment composition, mineralogy, and geochemistry of arsenic (As)-contaminated alluvial aquifers in the Ganges-Brahmaputra floodplain in the central Bangladesh. Arsenic concentrations in 85 tubewells in Manikganj area, 70 km northwest of Dhaka City, range from 0.25 microg/L to 191 microg/L with a mean concentration of 33 microg/L. Groundwater is mainly Ca-HCO(3) type with high concentrations of dissolved As, Fe, and Mn, but low level of SO(4). The uppermost aquifer occurs between 10 m and 80 m below the surface that has a mean arsenic concentration of 35 microg/L. Deeper aquifer (>100 m depth) has a mean arsenic concentration of 18 microg/L. Sediments in the upper aquifer are mostly gray to dark-gray, whereas sediments in the deep aquifer are mostly yellowing-gray to brown. Quartz, feldspar, mica, hornblende, garnet, kyanite, tourmaline, magnetite, ilmenite are the major minerals in sediments from both aquifers. Biotite and potassium feldspar are dominant in shallow aquifer, although plagioclase feldspar and garnet are abundant in deep aquifer sediments. Sediment composition suggests a mixed provenance with sediment supplies from both orogenic belts and cratons. High arsenic concentrations in sediments are found within the upper 50 m in drilled core samples. Statistical analysis shows that As, Fe, Mn, Ca, and P are strongly correlated in sediments. Concentrations of Cd, Cu, Ni, Zn, and Bi also show strong correlations with arsenic in the Manikganj sediment cores. Authigenic goethite concretions, possibly formed by bacteria, are found in the shallow sediments, which contain arsenic of a concentration as high as 8.8 mg/kg. High arsenic concentrations in aquifers are associated with fine-grained sediments that were derived mostly from the recycled orogens and relatively rapidly deposited mainly by meandering channels during the Early to Middle Holocene rising sea-level conditions.  相似文献   
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This study attempts to investigate the presence of a regional Environmental Kuznets Curve (EKC) in selected South Asian countries, namely, Pakistan, India, Bangladesh, and Sri Lanka for the period 1984–2008. In addition, it also intends to inspect the impact of corruption on environmental degradation in this region. The Fixed Effect results confirm the existence of the regional EKC in these countries. Furthermore, the results indicate that corruption do affect environment in the manner that it delays the turning point in EKC. It is found that, in the presence of corruption, the per capita GDP at the turning point is USD 998, which is USD 128 higher from the value that would have been in the absence of corruption. Based on these results, the study suggests appropriate policy measures.  相似文献   
87.
Wetlands are among the most productive ecosystems on the earth. They produce various market and non-market goods and services, which have a significant role in human welfare. Despite the great opportunities from sustainable development, wetlands all over the world are under serious threat from a diverse range of non-sustainable activities. One of the major reasons for excessive depletion and the conversion of wetland resources is due to underestimating the non-market values of wetlands during development decisions. Shadegan International Wetland (SIW) in southern Iran is one of these wetland areas that is threatened by undervaluation and overexploitation from commercial activities. This study utilizes the contingent valuation method to estimate the economic benefits of SIW from the view point of peoples’ willingness to pay (WTP). The logit model was defined based on dichotomous choice to measure individuals’ WTP. The estimated mean WTP was US$ 1.74 per household as a onetime donation. This study concludes that the benefits of SIW to society could encourage managers to set priorities to ensure that the health of the ecosystem, its integrity, and its uniqueness would be conserved in a proper manner.  相似文献   
88.
The inclusion of both non-use values and values placed by non-users provide more reliable results about the real values of wetlands. A choice experiment method was conducted to estimate the willingness to pay for environmental conservation in non-users’ communities adjacent to the Shadegan International Wetland (SIW) in Iran. A random parameter logit (RPL) model was developed to derive the marginal value and compensating surplus of the respondents for five attributes of the non-market values of SIW. The trade-off between five different wetland attributes showed that water quality improvement and biodiversity conservation were the most highly valued attributes. The results demonstrated that about 66 % of non-users were willing to donate money for the contribution in SIW conservation, suggesting that non-users have the potential to contribute to SIW conservation programs.  相似文献   
89.
Sixty home made wine and sixty-four grape samples were collectedfrom five territories in Jordan, where grapes and wine aremostly producted. The collected samples were analyzed for themost used organochlorine pesticides (OCP) and organophosphorouspesticides (OPP) in Jordan, as well as for four heavy metals(Ni, Cu, Zn and Pb). The results showed that OCPs residues weredetected in 73% of the wine samples but no OPPs residue weredetected which is due to generally shorter half life of thelater pesticide. Grapes showed higher incident of contaminationthan wine, however, OCPs and OPPs with both short and longhalf-lives were detected. The OPPs were detected in only8.3% of the analyzed grape samples. Heavy metals showed higher valuesin grapes than in the wine samples and it was attributed toremoval of solids during wine preparation processes or throughcontamination of wine during storage. Most of the samples werebelow toxic limit.  相似文献   
90.
In this study, the aqueous extract of leaves of the plant cock's comb (Celosia argentea) was fractioned into five batches using n-hexane, dichloromethane, ethyl acetate, and n-butanol, respectively. High performance liquid chromatography analysis of the methanol re-dissolved residues of 3 polar fractions, including dichloromethane, ethyl acetate, and n-butanol separately which exhibited altogether 12 compounds identified as 4-hydroxycinnamic acid (p-coumaric acid), 4-hydroxybenzoic acid, protocatechuic acid, caffeic acid, m-coumaric acid, gallic acid, 4-hydroxybenzaldehyde, m-hydroxybenzaldehyde, 2,4-dihydroxybenzoic acid, pyrogallol, 3,5-dihydroxybenzoic acid, and genetic acid was categorized by retention time using known compounds. Similarly, the mass confirmation of most of the identified compounds was achieved by injecting 20 µl of composite sample of these three polar fractions into liquid chromatography–mass spectrometry. Similarly, the physiochemical analysis of C. argentea aqueous extract showed the presence of various constituents such as phenols, flavonoids, tannins, and glycosides. All four organic fractions were examined for phytotoxicity against Lepidium sativum. Analysis of variance showed significant differences among these fractions against germination and growth of L. sativum. Further allelopathic effects appeared to be concentration dependent. Thus, C. argentea may prove effective as a substitute of herbicides to control the weeds like L. sativum from attacking crops and to protect the environment from the health hazard effects of herbicides.  相似文献   
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