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51.
Nada Horvatinčić José Luis Briansó Bogomil Obelić Jadranka Barešić Ines Krajcar Bronić 《Water, Air, & Soil Pollution: Focus》2006,6(5-6):475-485
The process of eutrophication in form of intense plant growth has been observed in some lakes and water streams at the Plitvice
Lakes National Park in central Croatia. Here we investigate whether this phenomenon is a consequence of anthropogenic pollution
or due to naturally produced organic matter in the lakes. We applied chemical analysis of water at two springs and four lakes
(nutrients, dissolved organic carbon (DOC), trace elements) and measurements of surface lake sediments (mineral and organic
fraction analyses, trace elements) in four different lakes/five sites. The chemical composition of water does not indicate
recent anthropogenic pollution of water because the concentrations of most trace elements are below detection limits. The
concentrations of DOC and nutrients are slightly higher in the area of increased eutrophication-plant growth. Also the content
of organic matter in the sediment is at the highest level in areas with highest C/N ratio indicating that the organic fraction of this sediment is mainly of terrestrial origin. There is no significant difference
among the trace element concentration in the upper segment of all cores, deposited approximately during last 50 years when
higher anthropogenic influence is expected due to development and touristic activity, and the lower part of the cores, corresponding
to the period approximately 100–200 years before present. The content of trace elements and organic matter in sediments decreases
from the uppermost lake downstream. According to our results there is no indication of recent anthropogenic pollution in water
and sediment. Higher concentrations of DOC in water as well as phosphorus and some other elements in the lake sediment can
be a consequence of input of natural organic matter to the lake water. 相似文献
52.
论述了中国燃煤工业锅炉SO2污染防治技术的选择及评价,其中主要包括:《中国燃煤工业锅炉SO2污染综合防治对策》的产生、主要内容、特点、选择、评价及其实施的意义。 相似文献
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Felipe Hernndez‐Luis Mercedes Lemus Domingo Grandoso Mario V. Vzquez Carmen D. Arbelo 《补救:环境净化治理成本、技术与工艺杂志》2004,14(3):105-112
This article presents the results of an experimental study conducted to evaluate the behavior of two types of andisol soils found in Tenerife, Canary Islands, Spain. The soils were evaluated in relation to their buffering capacity when confronted with acid and alkaline fronts generated during electroremediation treatment. The study was conducted using a cell, which established a continuous flow of distilled water through electrode chambers to remove H+ and OH? generated during electrolysis. The results indicate that the soils had sufficient buffer capacity to support variations in pH independent of the maintenance of flow of solution in the electrode chambers. Although the mechanism of migration was not affected, the flow of water favored the movement of ions by diffusion monitoring of the electrolytic current allowed for a real‐time parameter to act as an indicator of the quantity of ions available in regions near the electrodes. © 2004 Wiley Periodicals, Inc. 相似文献
55.
UV/O3复合降解水中2,4-二氯酚的试验研究 总被引:2,自引:1,他引:2
以紫外光源为主要依托,变换反应器中的不同工艺条件,分别对紫外光、臭氧和紫外/臭氧三种不同于工艺条件对水中污染物2,4-二氯酚(2 ,4-DCP)的降解规律进行研究.结果表明,UV/O3复合对2,4-DCP的降解较UV、O3单独作用效果好;溶液的酸碱度影响UV/O3对2 ,4-DCP的降解;此外,溶液中含有细菌时,E. coli的杀灭效果仍表现为UV/O3>O3>UV.细菌的杀灭和2,4-DCP的降解均消耗羟基自由基,形成竞争反应,从而影响到2,4-DCP的降解效果. 相似文献
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Krista Harper Catherine Sands Diego Angarita Horowitz Molly Totman Monica Maitín Jonell Sostre Rosado 《Local Environment》2017,22(7):791-808
How do youth learn through participation in efforts to study and change the school food system? Through our participatory youth action research (YPAR) project, we move beyond the “youth as consumer” frame to a food justice youth development (FJYD) approach. We track how a group of youth learned about food and the public policy process through their efforts to transform their own school food systems by conducting a participatory evaluation of farm-to-school efforts in collaboration with university and community partners. We used the Photovoice research method, placing cameras in the hands of young people so that they themselves could document and discuss their concerns and perspectives. The research was designed to gain insight about youths’ knowledge of food, health, and community food systems. Drawing upon the youth group’s insights, we build a framework for building critical consciousness through FJYD. 相似文献
58.
Molinos-Senante María Porcher Simon Maziotis Alexandros 《Environmental science and pollution research international》2017,24(20):16994-17005
Environmental Science and Pollution Research - The assessment of productivity change over time and its drivers is of great significance for water companies and regulators when setting urban water... 相似文献
59.