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511.
深圳盐田垃圾场对周围土壤污染状况分析 总被引:10,自引:1,他引:10
结合深圳市盐田区垃圾场处置工程,对垃圾场周围土壤污染状况进行了分析研究。结果表明,盐田垃圾场主场垃圾已对周围环境造成二次污染:除Hg、Ni含量降低外,低位土壤的其余重金属含量大于高位土壤表明周围土壤已受到垃圾堆放场的重金属污染。 相似文献
512.
不同粒径近地表大气尘元素分配规律研究——以成都经济区为例 总被引:3,自引:0,他引:3
将不同地貌单元和城市不同功能区的近地表大气尘机械筛分,分析其粒度组成和化学组成特征及其相互关系,以探讨元素在不同粒径大气尘颗粒中的分配规律。研究结果表明:近地表大气尘颗粒粒径主要集中在300~400目(38.5~54μm),其中城市和丘陵地区质量分数最高,达56.596%~68.493%。化学组成上,人为扰动重金属元素,除Pb本底值比较高外,总体上城市高于丘陵和山区;Al2O3、Na2O、SiO2、Ti、Zr等稳定元素总体上,随粒径的减小,元素含量逐渐增大;Mn、P、S等元素,总体上随粒径的减小,元素含量逐渐减小。Pb、Zn、Cr等人为扰动元素,大粒径近地表大气尘元素含量稍大于小粒径元素含量,但小粒径元素含量总体上仍呈现随粒径的减小而逐渐增大的趋势。 相似文献
513.
基于主成分分析和水质标识指数的天津地区主要河流水质评价 总被引:8,自引:0,他引:8
于2009年5月(枯水期)、8月(丰水期)、11月(平水期)对天津地区蓟运河、潮白新河、永定新河、金钟河、北塘排污河、黑猪河、海河、大沽排污河、独流减河、青静黄排水渠、子牙新河和北排水河12条主要河流的水质进行监测,并对监测数据进行主成分分析,构建水质评价指标体系,采用水质标识指数进行水质评价。结果表明,主成分分析与水质标识指数相结合的评价方法客观可靠。从时间分布来看,枯水期水质最差,58.3%的河流为劣Ⅴ类水质,部分河流已经黑臭,8月水质较好。从综合水质标识指数来看,海河以南河流污染较为严重。该地区河流NH3-N污染最为严重,其次是BOD5、CODMn和TP,属于有机型及富营养化污染。 相似文献
514.
采用原子吸收分光光度法、原子荧光法和电感耦合等离子体发射光谱法测定了贾鲁河表层沉积物中6种重金属的含量,用灼烧法测定贾鲁河表层沉积物中有机质含量。运用地累积指数法对贾鲁河流域表层沉积物中重金属污染状况进行评价,并且通过主成分分析法研究贾鲁河重金属污染来源。结果表明:贾鲁河表层沉积物中As、Cu、Ni、Zn的含量比2004年淮河表层沉积物中相应重金属含量明显偏高。重金属污染程度为:As〉Cu〉Zn〉Pb〉Ni〉Cr。通过主成分分析进一步对重金属来源的确定,发现前2个主成分的贡献率分别为58.85%和19.74%,污染来源主要有两类,分别是工农业、生活排污的点源污染,自然变化对沉积物的影响,岩石风化与侵蚀过程和有机质降解矿化的内源污染。 相似文献
515.
Tausz M Landmesser H Posch S Monschein S Grill D Wienhaus O 《Environmental monitoring and assessment》2007,128(1-3):75-82
In this work we measured a set of antioxidative and photoprotective compounds (chlorophylls, carotenoids, tocopherol, ascorbate
and glutathione), which were suggested previously as stress markers in conifer needles, at two spruce forest sites at different
elevation in Saxony, Germany. Most variables differed significantly between current and 1-year-old needles, but only the content
of the xanthophyll cycle per mg total chlorophyll and the oxidation state of glutathione were significantly different between
the sites. We applied principal component analysis (PCA) to address the question if underlying accumulated variables are similar
to the ones found in spruce needles across Alpine elevation profiles and/or for pines in Mediterranean ecosystems. Four principal
components (accumulated variables, PC) representing 68% of the total variance of the dataset were extracted. PC 1 encompassed
total chlorophyll, lutein, and β-carotene contents, PC 2 combined the epoxidation state of xanthophylls, ascorbate content
and redox state, and glutathione content, PC 3 represented the content of xanthophylls and the redox state of glutathione,
and PC 4 encompassed the content of α-carotene and the epoxidation state of xanthophylls. Only PC 3 was significantly different
between sites. The PCA structure shows many similarities to corresponding findings in studies on spruce in mountain forests
in the Alps and pines in Mediterranean systems. This corroborates the interpretation of PCs as indicative for underlying physiological
processes. However, separation of the two investigated sites by PCs was in the present case study not superior to the separation
by single input variables. 相似文献
516.
517.
多元统计分析在四川退耕还林区土壤肥力评价中的运用 总被引:6,自引:0,他引:6
以四川洪雅退耕还林区4种退耕还林模式和农耕地17个土壤肥力指标为例,采用多元统计的主成分分析法对土壤肥力等级进行综合评价. 借助SPSS统计软件得出土壤肥力指标前5个主成分的累计贡献率为84.17%,已足够反映原指标信息. 这5个主成分分别概括为:①土壤有效磷,铵态氮,pH水浸,水解氮,全氮,硝态氮和全磷指标;②土壤全钾、速效钾和缓效钾指标;③土壤总孔隙度、毛管孔隙度和最大持水量指标;④土壤容重,毛管持水量,pH盐浸指标;⑤土壤有机质指标. 借助SPSS统计软件计算主成分因子的综合得分. 结果显示:就各模式土壤上层比较,模式Ⅲ(牛鞭草)上层在综合得分中排名第一. 就各模式土壤下层比较,模式Ⅱ(苦竹+牛鞭草)下层在综合得分中排名第一. 相似文献
518.
519.
Heavy metal contamination and source in arid agricultural soil in central
Gansu Province, China 总被引:4,自引:0,他引:4
Concentrations of copper (Cu), lead (Pb), chromium (Cr), mercury (Hg), and arsenic (As) were measured in arid agricultural and irrigated agricultural soils collected in Daba Village, Shajiawuan Village, Gangou Village and Sifangwu Village, located in central Gansu Province, China. Concentrations except Hg and Pb were lower than the background values in grey calcareous soil in the selected arid agricultural soils. Pb concentration exceeded the threshold of arid agricultural soils in China by 72.46%. These results showed that there was indeed serious pollution with Pb, a slight pollution problem for other selected metals in the irrigated agricultural soils in Daba Village. Principal component analysis (PCA) was used to assess the soil data, applying varimax rotation with Kaiser Normalization. The result showed that the irrigated factor, agricultural factor and anthropogenic factor all contributed to the relations between selected chemical properties. The main factor of accumulation of Cu, Pb, Cr, Hg and As was lithological factor in arid agricultural areas. There is a striking dissimilarity of origin of Cu, Pb, Cr, Hg and As in agricultural soil between the irrigate agriculture and arid agriculture. 相似文献
520.
Analysis of Mosses and Soils for Quantifying Heavy Metal Concentrations in Sicily: A Multivariate and Spatial Analytical Approach 总被引:1,自引:0,他引:1
Gramatica P Battaini F Giani E Papa E Jones RJ Preatoni D Cenci RM 《Environmental science and pollution research international》2006,13(1):28-36
- DOI: http://dx.doi.org/10.1065/espr2006.01.006
Background The use of vegetal organisms as indicators of contamination of the environment is partially replacing traditional monitoring
techniques. Amongst the vegetal organisms available, mosses appear to be good bioindicators and are used for monitoring anthropogenic
and natural fall-out on soils. This study has two objectives: the evaluation of the concentrations of heavy metals in soils
and mosses of the Sicily Region, in Italy and the identification of the origin of fall-out of heavy metals.
Methods Mosses and the surface soil were sampled at 28 sites, only the youngest segments of Hylocomium splendens and Hypnum cupressiforme,
corresponding to the plant tissues produced during the last 3 years, were taken. The elements Cd, Cu, Ni, Pb and Zn were analysed
by ICP-MS and Hg by AAS. Statistical analysis was by PCA and spatial representation by GIS.
Results and Discussion In the mosses sampled in Sicily, the highest concentrations of Cd were found around the cities of Palermo and Messina. The
highest concentrations of Hg were recorded in the northern part of the island between Trapani and Messina, similar to the
distribution of Cu. Different areas with the highest concentrations of Ni were found near the south coast, in the vicinity
of Palermo and around the Volcano Etna. The highest concentrations of Pb were found in the south-west coast near Agrigento,
where important chemical plants and petroleum refineries are located. Except for a few locations, Zn fall-out was found to
be evenly distributed throughout Sicily.
Conclusion The sites where the concentrations of heavy metals cause greatest concern have been revealed by the PCA analysis and portrayed
using GIS. Also of some concern is the diffuse and anthropogenic origin of Hg and Cd. The combined approach of using soil
and mosses, together with pedological interpretation and application of multivariate statistical techniques has provided valuable
insight into the environmental aspects of heavy metal deposition in a region of southern Europe.
Recommendations and Outlook Further insight into the deposition of heavy metals will require more detailed sampling of soils and mosses in both new and
previous study areas. This needs to be complemented by detailed pedological investigations in the study areas. Future research
programmes will address these issues. 相似文献