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81.
Anthropogenic activities create various contaminated leachate, which can migrate downward from the vadose zone to groundwater,
transferring contaminants, including some hazardous ones.
When these various sources of contamination influence the groundwater aquifer simultaneously, the effects of contamination
are enhanced.
The major concern of this study has been to determine whether the shape of a groundwater chlorograph might be the result of
such deterministic effects as accumulation of one or more particular processes of groundwater contamination, and how this
might relate to specific hydrological situations.
This study proposes a classification of groundwater contamination on the basis of properties of the main components of groundwater
quality graphs and the corresponding hydrogeological/environmental situation.
The study further suggests that contamination of groundwater in any hydrogeological situation (e.g. sea water) may be graphically
expressed.
A variety of chlorographs and nitrographs, representative of various groundwater aquifers sampled from a number of wells throughout
Israel attest to this.
The study thus indicates that groundwater quality graphs may be considered as a complementary tool for groundwater quality
control and better understanding aquifer situations. 相似文献
82.
长江下游江段铜鱼肌肉营养成分分析 总被引:7,自引:0,他引:7
对采自长江下游江段的铜鱼(Coreius heterodom)肌肉营养成分进行了测定和分析。结果表明,铜鱼肌肉水分、粗蛋白质、粗脂肪和粗灰分占鲜样的比例分别为:70.03%、20.54%、6.82%和1.38%;按照氨基酸评分(Amino Acid Score,AAS)和化学评分(Chemical Score,CS)标准,铜鱼限制性氨基酸为缬氨酸和异亮氨酸,必需氨基酸指数(EAAI)为81.52;不饱和脂肪酸和ω-3多不饱和脂肪酸含量分别为63.03%和2.0%;肌肉中常、微量元素含量最高分别为钾(3135μg/g)和铁(5.46μg/g),锌铜比和锌铁比分别为8.85和0.65。 相似文献
83.
A statistical study of the dependence between various critical fusion temperatures of a certain kind ofcoal and its chemical components is carried out.As well as using classical dependence techniques(multiple,stepwise and PLS regression,principal components,canonical correlation,etc.)together withthe corresponding inference on the parameters of interest,non-parametric regression and bootstrapinference are also performed. 相似文献
84.
The carbonate factories, their controlling factors and their palaeoecological and sedimentological signals recorded in sedimentary successions are key elements for understanding the evolution of carbonate platform systems. Luis Pomar has dedicated most of his academic life to the study of carbonate rocks and carbonate factories. The idea for this special issue to celebrate Pomar’s career arose during a session at the 34th International Association of Sedimentologists meeting held in Rome, entitled ‘Understanding carbonate factories through palaeoecological and geochemical signals’. The proposal encountered great response among participants, and additional contributions followed an email invitation to other specialists. This issue contains a variety of papers on carbonate sedimentology and carbonate factories. Here, an introduction that contextualizes the papers and key concepts discussed in this thematic issue is provided. It reviews Luis Pomar’s major achievements in carbonate sedimentology and discusses the evolution of the concept of the carbonate factory and the series of palaeoecological and sedimentological signals used to characterize the wide spectrum of carbonate depositional systems found in the natural world. 相似文献
85.
Quantifying the variability and allocation patterns of aboveground carbon stocks across plantation forests is central in deriving accurate and reliable knowledge and understanding of the extent to which these species contribute to the global carbon cycle and towards minimizing climate change effects. The principal objective of this study was to quantify the variability and allocation patterns of aboveground carbon stocks across Pinus and Eucalyptus plantation forests, tree-structural attributes (i.e. stems, barks, branches and leaves) and age groups, using models developed based on remotely sensed data. The results of this study demonstrate that aboveground carbon stocks significantly (α = 0.05) vary across different plantation forest species types, structural attributes and age. Pinus taeda and Eucalyptus grandis species contained aboveground carbon stocks above 110 t C ha−1, and Eucalyptus dunii had 20 t C ha−1. Across plantation forest tree structural attributes, stems contained the highest aboveground carbon stocks, when compared to barks, branches and leaves. Aboveground carbon stock estimates also varied significantly (α = 0.05) with stand age. Mature plantation forest species (i.e. between 7 and 20 years) contained the highest aboveground carbon stock estimates of approximately 120 t C ha−1, when compared to younger species (i.e. between 3 and 6 years), which had approximately 20 t C ha−1. The map of aboveground carbon stocks showed distinct spatial patterns across the entire study area. The findings of this study are important for understanding the contribution of different plantation forest species, structural attributes and age in the global carbon cycle and possible climate change moderation measures. Also, this study demonstrates that data on vital tree structural attributes, previously difficult to obtain, can now be easily derived from cheap and readily-available satellite data for inventorying carbon stocks variability. 相似文献
86.
临港石化集聚对城镇人居环境影响的居民感知——宁波镇海案例 总被引:2,自引:0,他引:2
沿海港口地区大量地集聚化工企业,导致生态环境型邻避冲突在滨海港口城市不断涌现.利用问卷调查、半结构访谈对镇海居民入户抽样,调查石化企业集聚对人居环境影响的居民感知.结果表明:①石化企业集聚的潜在危险与环境排放构成的居住安全、环境污染是集聚区环境外部性的首要负外部性,是影响城市人居环境的重要方面;②本地居民认知的石化集聚区环境外部性对人居环境影响的空间特征符合地理学第一定律,且青年、中青年、老年群体的感知差异初现文化集团性;③初步证实人居环境是有效刻画城市产业空间组织及其环境外部性的综合媒介,将成为政府破解“环境抗争事件”和城市产业升级的着力点.研究成果为深入理解城市产业功能区升级与城镇人居环境建设需求及阶层偏好提供了案例,同时对指导城市产业空间优化与宜居城市建设具有重要的现实意义. 相似文献
87.
Zheng-Gang Li Yan-Hui Dong Ji-Qiang Liu Ling Chen 《International Geology Review》2015,57(5-8):978-997
Seamounts are an integral part of element recycling in global subduction zones. The published trace element and Pb-Sr-Nd isotope data for basaltic lavas from three key segments (Central Lau Spreading Ridge (CLSR), Eastern Lau Spreading Ridge (ELSR), and Valu Fa Ridge (VFR)) of the Lau back-arc basin were compiled to evaluate the contribution of Louisville seamount materials to their magma genesis. Two geochemical transitions, separating three provinces with distinct geochemical characteristics independent of ridge segmentation, were identified based on abrupt geochemical shifts. The origin of the geochemical transitions was determined to be the result of drastic compositional changes of subduction components added into the mantle source, rather than the transition from Indian to Pacific mid-ocean ridge basalt (MORB) mantle, or due to variable mantle fertilities. The most likely explanation for the drastic shifts in subduction input is the superimposition of Louisville materials on ‘normal’ subduction components consisting predominantly of aqueous fluids liberated from the down-going altered oceanic crust and minor pelagic sediment melts. Quantitative estimation reveals that Louisville materials contributed 0–74% and 21–83% of the Th budget, respectively, to CLSR and VFR lavas, but had no definite contribution to the lavas from the ELSR, which lies farthest away from the subducted Louisville seamount chain (LSC). The spatial association of the subducted LSC with the Louisville-affected segments suggests that the Louisville signature is regionally but not locally available in the Tonga subduction zone. Besides, the preferential melting of subducted old Cretaceous LSC crust instead of the old normal Pacific oceanic crust at similar depths implies that elevated temperature across the subduction interface or seamount erosion and rupture were required to trigger melting. A wider implication of this study, thus, is that seamount subduction may promote efficiency of element recycling in subduction zones. 相似文献
88.
89.
DAVID LEE DUEWER 《地理学报(英文版)》1990,(4)
The Free-Wilson paradigm is an established and powerful tool for quantitatively relating activity withchemical structure.Current implementations of the paradigm,however,are flawed both conceptually andin execution.As part of an attempt to more fully realize the promise of the paradigm,it was necessaryto examine these limitations in detail.This report introduces a robust,theory-founded Free-Wilson implementation:stepwise principalcomponents regression analysis(SPCRA).SPCRA is computationally superior to previousimplementations but does not in itself correct their conceptual flaws.The development of SPCRA did,however,facilitate derivation of a simple and chemically significantinterpretation of the Free-Wilson structure-activity model.A number of statistical aspects of this modelcommonly misused in previous applications are discussed at length.These discussions provide criticalbackground for the development of an alternative implementation of the Free-Wilson paradigm. 相似文献
90.
The major ion composition of Great Artesian Basin groundwater in the lower Namoi River valley is relatively homogeneous in chemical composition. Traditional graphical techniques have been combined with multivariate statistical methods to determine whether subtle differences in the chemical composition of these waters can be delineated. Hierarchical cluster analysis and principal components analysis were successful in delineating minor variations within the groundwaters of the study area that were not visually identified in the graphical techniques applied. Hydrochemical interpretation allowed geochemical processes to be identified in each statistically defined water type and illustrated how these groundwaters differ from one another. Three main geochemical processes were identified in the groundwaters: ion exchange, precipitation, and mixing between waters from different sources. Both statistical methods delineated an anomalous sample suspected of being influenced by magmatic CO2 input. The use of statistical methods to complement traditional graphical techniques for waters appearing homogeneous is emphasized for all investigations of this type. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献