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831.
A reproductive-health knowledge, attitudes and practices (KAP) survey was carried out among 468 Afghan women of reproductive age. A convenience sample of women was selected from attendees in the outpatient departments of four health facilities in Kabul. Seventy-nine per cent of respondents had attended at least one antenatal consultation during their last pregnancy. Two-thirds (67 per cent) delivered their first child between 13 and 19 years. The Caesarean-section rate was low (1.6 per cent). Two-thirds (67 per cent) of deliveries occurred in the home. The contraceptive prevalence rate was 23 per cent (16 per cent modern and 7 per cent natural methods). Twenty-four per cent had knowledge of any STIs, although most of these women did not know correctly how to prevent them. Most of the women (93 per cent) needed authorization from their husband or a male relative before seeking professional health-care. In multivariate analysis, women's schooling was significantly associated with antenatal-care attendance (AOR 4.78), institutional delivery (AOR 2.29), skilled attendance at birth (AOR 2.07) and use of family planning (AOR 4.59). Reproductive-health indicators were noted to be poor even among these women living in Kabul, a group often considered to be the most privileged. To meet the reproductive-health needs of Afghan women, the socio-cultural aspects of their situation--especially their decision-making abilities -- will need to be addressed. A long-standing commitment from agencies and donors is required, in which the education of women should be placed as a cornerstone of the reconstruction process of Afghanistan. 相似文献
832.
The size and isotopic behavior of sulfur pools in210Pb-dated peat cores were investigated to obtain aninsight into retention mechanisms of pollutant S in twomountain-top peatlands of the Northern Czech Republic, CentralEurope. The bogs were situated 40 km apart in an area whichbetween the years 1985 and 1995 received as much as 130 kg Sha-1 yr-1 from the atmosphere. Vertical peataccretion was faster at Pod Jelení horou (JH) than atVelký moál (VM). Organic carbon-bonded S was themost abundant sulfur pool, constituting 77 and 65 wt. % at JHand VM, respectively. At JH both the S concentration maximumand the highest annual S deposition rate were displaceddownward by more than 20 years (from 1987 to the 1960s)indicating that the buried S is vertically mobile. At VM the Sconcentration was the highest in the topmost 2-cm section eventhough atmospheric S deposition peaked in 1987. Differentmechanisms of S isotope redistribution prevailed in thetopmost peat layers at JH, where a negative 34Sshift occurred, and at VM, where a positive 34Sshift occurred. Bacterial sulfate reduction was responsiblefor the negative 34S shift at JH. One possibleexplanation of the positive 34S shift at VM isrelease of 32S-enriched products of mineralization duringpeat diagenesis. There was a strong positive correlationbetween the abundance of total and pyrite S along the profiles.The presence of pyrite S at VM (526 ± 60 ppm) suggestedthat even at VM bacterial sulfate reduction occurred. Ananaerobic incubation of JH peat indicated sulfate reductionrate of 600 nmol g-1 day-1. The turnover times forinorganic S pools were shorter than for the organic S pools.Cumulative S contents in the Czech peat bogs were found to besignificantly lower than in similar sites in the NortheasternU.S., even though the atmospheric S inputs were more thanthree times higher at the Czech sites. Possible causes of suchdiscrepancy are discussed. 相似文献
833.
Kylefors K 《Journal of environmental management》2003,68(4):367-376
Landfills generate emissions in the form of gas and leachate. The emissions are often measured within monitoring programmes. It is likely that the requirements of such monitoring programmes can be extended in the future, particularly in light of the increased interest in specific organic substances. Multivariate data analyses (MVDA) have been used to evaluate the possibility of predicting the content of specific organic substances from more common analyses. The results indicate that this is possible for a specific leachate. MVDA can also be used to reduce the number of analyses performed within existing monitoring programmes while retaining information about all the variables formerly included in the programmes. 相似文献
834.
Lowest Effect Levels of Lead and Mercury on Decomposition of Mor Layer Samples in a Long-Term Experiment 总被引:2,自引:0,他引:2
Indications of possible negative effects of lead (Pb) and mercury(Hg) on microbial respiration in Southern Swedish forest humus layers led to experiments on dose-response relationships by additions of metal salts in the laboratory. Respiration rates andweight loss due to decomposition of organic material were measured. For relevance to field situations metal doses were low,the time span was long, 550 days including freeze storage, and microbial activity was kept up by plant litter additions. We looked for effects of Pb and Hg at levels moderately elevated above the Southern Swedish reference, as well as combined effectsof Pb + Hg. A reduction in respiration and decomposition of10% was found at about 225–245 g g-1 of total Pb, i.e. ata Pb level elevated 3.5 times. Although small effects of Hg werefound even at the lowest dose level, 10% inhibition of microbialactivity appeared temporarily at about 2–3 g g-1 of total Hg, i. e. at 6–8 times the reference level. There were nolong-term additive effects of Pb and Hg on decomposition. Type of anion had a strong influence on the test, chlorides of Pbbeing more toxic than nitrates. Long-term monitoring and maintenance of microbial activity during the experiment were prerequisites for the occurrence of effects at low metal levels. 相似文献
835.
Brännvall M.-L. Bindler R. Emteryd O. Renberg I. 《Water, Air, & Soil Pollution: Focus》2001,1(3-4):357-370
In order to understand the fate of anthropogenic lead (Pb)pollution in boreal forest soils, and to predict future trends, it is important to know where in the soil the pollution Pb is accumulated and how large the pollution and natural Pb inventories are in different soil horizons. We combined stable Pb isotope (206Pb/207Pb ratios) and concentration analyses to study Pb in podzol profiles and mor samples from old-growth forest stands at seven sites distributed from southern to northern Sweden. Additional samples were taken from managed forests, and from an agricultural field, to give some idea of the effects of land-use. Pb concentrations are typically 60–100 g g-1 dry mass in the mor layer in southern Sweden and about 30 g g-1 in northern Sweden. Pb isotope analyses show that virtually all of this Pb is pollution Pb. The isotope composition also shows that pollution Pb has penetrated downwards between 20–60 cm in the forest soils. The total pollution Pb inventories vary between 0.7–3.0 g m-2 ground surface, with larger inventories in southern compared to northern Sweden. Although the highest Pb concentrations occur in the mor layer, the largest inventories of pollution Pb are found in the Bs-horizon. The limited investigation of Pb distribution and inventories in soils from managed forests did not point to any major difference compared to the old-growth forests. The agricultural field revealed, however, a completely deviating Pb profile with all pollution Pb evenly distributed in the 20 cm thick top-soil. 相似文献
836.
Conservation strategies for effective land management of protected areas using an erosion prediction information system (EPIS) 总被引:1,自引:0,他引:1
This research demonstrates the predictive modeling capabilities of a geographic information system (GIS)-based soil erosion potential model to assess the effects of implementing land use change within a tropical watershed. The Revised Universal Soil Loss Equation (RUSLE) was integrated with a GIS to produce an Erosion Prediction Information System (EPIS) and modified to reflect conditions found in the mountainous tropics. Research was conducted in the Zenzontia subcatchment of the Río Ayuquíla, located within the Sierra de Manantlán Biosphere Reserve (SMBR), México. Expanding agricultural activities within this area will accentuate the already high rate of soil erosion and resultant sediment loading occurring in the Río Ayuquíla. Two land-use change scenarios are modeled with the EPIS: (1) implementation of soil conservation practices in erosion prone locations; and (2) selection of sites for agricultural expansion which minimize potential soil loss. Confronted with limited financial resources and the necessity for expedient action, managers of the SMBR can draw upon the predictive capacity of the EPIS to facilitate rapid and informed land-use planning decisions. 相似文献
837.
Evaluation of groundwater and soil pollution in a landfill area using electrical resistivity imaging survey 总被引:8,自引:0,他引:8
Landfills are sources of groundwater and soil pollution due to the production of leachate and its migration through refuse.
This study was conducted in order to determine the extent of groundwater and soil pollution within and around the landfill
of Seri Petaling located in the State of Selangor, Malaysia. The condition of nearby surface water was also determined. An
electrical resistivity imaging survey was used to investigate the leachate production within the landfill. Groundwater geochemistry
was carried out and chemical analysis of water samples was conducted upstream and downstream of the landfill. Surface water
was also analyzed in order to determine its quality.
Soil chemical analysis was performed on soil samples taken from different locations within and around the landfill in the
vadose zone (unsaturated zone) and below the water table (in the soil saturated zone). The resistivity image along line L–L1 indicated the presence of large zones of decomposed waste bodies saturated with highly conducting leachate. Analysis of trace
elements indicated their presence in very low concentrations and did not reflect any sign of heavy metal pollution of ground
and surface water or of soil.
Major ions represented by Na, K, and Cl were found in anomalous concentrations in the groundwater of the downstream bore hole,
where they are 99.1%, 99.2%, and 99.4%, respectively, higher compared to the upstream bore hole. Electrical conductivity (EC)
was also found in anomalous concentration downstream. Ca and Mg ions represent the water hardness (which is comparatively
high downstream). There is a general trend of pollution towards the downstream area. Sulfates (SO4) and nitrates (NO3) are found in the area in low concentrations, even below the WHO standards for drinking water, but are significantly higher
in the surface water compared to the groundwater. Phosphate (PO4) and nitrite (NO2), although present in low levels, are significantly higher at the downstream. There is no significant difference in the amount
of fluoride (F) in the different locations. In the soil vadose zone, heavy metals were found to be in their typical normal
ranges and within the background concentrations. Soil exchangeable bases were significantly higher in the soil saturated zone
compared to the vadose zone, and no significant difference was obtained in the levels of inorganic pollutants. With the exception
of Cd, the concentration ranges of all trace elements (Cu, Zn, Cr, Pb, and Ni) of Seri Petaling landfill soils were below
the upper limits of baseline concentrations published from different sources. 相似文献
838.
839.
油污土壤生物修复实验研究 总被引:1,自引:0,他引:1
为了有效预防和治理因石油开采、运输等造成的土壤污染,对大庆地区油污土壤进行了生物修复的实验研究,通过室内盆栽模拟实验,对芦苇和香蒲根际土壤的石油类污染物总含量、石油烃类组分浓度、非烃组分浓度进行了测定。结果表明,芦苇和香蒲对石油类污染物具有比较明显的降解作用,可以使被污染土壤中的某些油污成分逐渐被选择性消耗。实验还可看出,芦苇和香蒲对石油类污染物中正构烷烃的降解能力高于非正构烃。总体看,芦苇对石油类污染物的降解能力强于香蒲,但芦苇对非正构烃的降解能力略逊于香蒲。 相似文献
840.
Status of recycling end-of-life vehicles and efforts to reduce automobile shredder residues in Korea
Hyun-Tae Joung Sung-Jin Cho Yong-Chil Seo Woo-Hyun Kim 《Journal of Material Cycles and Waste Management》2007,9(2):159-166
The present end-of-life vehicle (ELV) recycle rate and management status during the dismantling stage were investigated to
aid the establishment of policies for the management of ELVs by surveying information and using the results gained from questionnaires
given to dismantlers. The average recycle rate at the dismantling stage was 44% of the mass of a new vehicle and the rest
of the ELV was then compressed and transported to shredding companies to recover mainly the iron content, which averaged 38.7%
of the mass of a new vehicle. Nonferrous metals such as copper, antimony, zinc, and aluminum accounted for only 1.5%. The
automobile shredder residues (ASRs) were composed of light and heavy fluffs and soil/dust and amounted to 15.8% based on the
mass of a new vehicle. The dumping of fluff and inorganic residues in landfill sites, however, will be restricted when new
regulations are implemented to reduce the disposal amount to less than 5% of a new car, as has been done in European countries
and in Japan. The detailed characteristics of ASR were investigated to suggest appropriate means of treatment such as volume
reduction or the utilization of thermal technologies to meet future expected enforcement. Also, some concerns on hazardous
pollutant release such as that of dioxins while utilizing such thermal treatment methods were considered. The present on-going
research and development projects to meet such future management targets are also introduced. 相似文献