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771.
长期以来,中国实行的是建设项目环境影响评价制度,但建设项目只处于整个决策链(战略、政策、计划、规划、项目)的末端,无法从源头上保护环境.规划环评是战略环评的重要组成部分,它可从源头上防止环境污染.中国2003年9月1日颁布实施的环评法对规划环评作了明确规定,标志着中国环评制度的发展完成了向全局性战略环评的转变,对促进经济社会环境的协调发展具有重大意义. 相似文献
772.
复合混凝剂处理印染废水的研究 总被引:1,自引:0,他引:1
聚合硫酸铝,聚合硫酸铁,以及更为复杂的聚合物硫酸铝铁作混凝剂处理COD为1000-3000mg/L印染废水的最佳工艺条件pH范围为7.5-8.5;搅拌速率为130r/min;搅拌时间为20分钟;一次处理混凝剂投加量为240mg/l,沉降时间为120分钟,COD去除率在85%左右。若分二次处理效果更好。 相似文献
773.
In the summer of 1998, the air quality (indicators: CO, NO, NO2, O3) above the water surface of the Lake Balderey (Essen, Ruhr area, North Rhine-Westphalia, Germany), an artificial lake used for recreation purposes, was measured using the Fourier transform infrared spectroscopy (FTIR) and differential optical absorption spectroscopy (DOAS) remote measurement methods. The lake, with an area of 3 km2 was created by damming the Ruhr and is surrounded by higher ground. In calm, bright weather conditions, this location results in a low-exchange situation (formation of temperature inversions, cold air dynamics) with a sustained impact on pollutant concentrations over the lake. The results of trace substance measurements (1/2 h mean values) were compared with values from comparison stations (suburban, high traffic and forest) located outside the area of the lake. In general, it was found that mean CO and NO concentrations over the lake were very low (0.3 ppm and 7.5 ppb, respectively). NO2 values (15 ppb) were some 3.5 times higher than those recorded at the forest station and O3 values, at 27 ppb, almost reached the same level as at the forest station (30 ppb). Mass flow densities as a function of wind direction, diurnal courses, differences between weekdays and weekends and comparisons with air quality standards are presented for the lake station. 相似文献
774.
Melanie von der Wiesche und Dietrich Werner 《Umweltwissenschaften und Schadstoff-Forschung》1998,10(3):179-187
Zusammenfassung Nach wie vor findet der Faktor Zeit in den Umweltwissenschaften zu wenig Beachtung. Langfristige Beobachtungen und Me?reihen
in der ?kologischen Forschung, wie sie für die Bewertung und Prognosen von Umweltzust?nden und-entwicklunger, unabdingbar
w?ren, scheinen die Ausnahme zu sein. Besonders komplexe ?kosysteme, wie terrestrische oder marine Systeme, kennzeichnen sich
auch durch l?ngere natürliche Eigenzeiten, die deshalb bei ihrer Erforschung berücksichtigt werden mü?ten. In diesem Zusammenhang
soll verdeutlicht werden, welche Rolle zeitliche Parameter speziell in der terrestrischen ?kosystemforschung spielen. Zu diesem
Zweck wurde eine Datenbank konzipiert, die Hauptcharakteristika von ?kosystemaren Analysen aufnehmen kann. Forschungsberichte
verschiedener ?kosystemforschungszentren wurden zur Aufnahme in die Datenbank bearbeitet. Gezielte Abfragen auf den Datenpool
erm?glichen dann eine Auswertung hinsichtlich der zeitlichen Ausrichtung bestimmter Untersuchungen. Dabei stellte sich — neben
einer teilweisen Ungleichheit der Zeitskalen von Experiment und Realit?t — u.a. heraus, da? l?ngerfristige Untersuchungen
?u?erst selten durchgeführt werden. So vielf?ltig die Gründe für dieses Defizit auch sein m?gen, sie k?nnen nicht von der
Forderung nach st?rkerer Berücksichtigung von langzeitlichen Beobachtungen ablenken, will die ?kosystemforschung die an sie
gestellten Aufgaben erfüllen.
相似文献
775.
A flux estimate of PCDDs and PCDFs through a waste water treatment plant has been made on an annual basis. The samples were collected from different steps in the treatment procedure within the plant i.e. inlet and outlet water, different sludge types and air samples. From the surroundings of the plant were collected samples of urban air, storm sewer water (urban runoff), plant discharge water and settling particulates from a sediment trap downstream the plant discharge. Differences in congener profiles were found between the samples taken within the plant compared to those collected outside. The flux of PCDD and PCDF equivalents through the plant was found to be approximately 0.4 – 0.5 g/year and the major part was taken away as digested sludge. 相似文献
776.
Snellinx Z Nepovím A Taghavi S Vangronsveld J Vanek T van der Lelie D 《Environmental science and pollution research international》2002,9(1):48-61
Nitroaromatics form an important group of recalcitrant xenobiotics. Only few aromatic compounds, bearing one nitro group as a substituent of the aromatic ring, are produced as secondary metabolites by microorganisms. The majority of nitroaromatic compounds in the biosphere are industrial chemicals such as explosives, dyes, polyurethane foams, herbicides, insecticides and solvents. These compounds are generally recalcitrant to biological treatment and remain in the biosphere, where they constitute a source of pollution due to both toxic and mutagenic effects on humans, fish, algae and microorganisms. However, relatively few microorganisms have been described as being able to use nitroaromatic compounds as nitrogen and/or carbon and energy source. The best-known nitroaromatic compound is the explosive TNT (2,4,6-trinitrotoluene). This article reviews the bioremediation strategies for TNT-contaminated soil and water. It comes to the following conclusion: The optimal remediation strategy for nitroaromatic compounds depends on many site-specific factors. Composting and the use of reactor systems lend themselves to treating soils contaminated with high levels of explosives (e.g. at former ammunition production facilities, where areas with a high contamination level are common). Compared to composting systems, bioreactors have the major advantage of a short treatment time, but the disadvantage of being more labour intensive and more expensive. Studies indicate that biological treatment systems, which are based on the activity of the fungus Phanerochaete chrysosporium or on Pseudomonas sp. ST53, might be used as effective methods for the remediation of highly contaminated soil and water. Phytoremediation, although not widely used now, has the potential to become an important strategy for the remediation of soil and water contaminated with explosives. It is best suited where contaminant levels are low (e.g. at military sites where pollution is rather diffuse) and where larger contaminated surfaces or volumes have to be treated. In addition, phytoremediation can be used as a polishing method after other remediation treatments, such as composting or bioslurry, have taken place. This in-situ treatment method has the advantage of lower treatment costs, but has the disadvantage of a considerable longer treatment time. In order to improve the cost-efficiency, phytoremediation of nitroaromatics (and other organic xenobiotics) could be combined with bio-energy production. This requires, however, detailed knowledge on the fate of the contaminants in the plants as well as the development of efficient treatment methods for the contaminated biomass that minimise the spreading of the contaminants into the environment during post harvest treatment. 相似文献
777.
Iesce MR Cermola F De Lorenzo F Graziano ML Caliendo B 《Environmental science and pollution research international》2002,9(2):107-109
Irradiation of carboxin (1) with a 500 W UV lamp (filter Pyrex) in CH3CN leads to the products 3, 5-8, 12-14 depending upon the reaction conditions. All photo-products were isolated and characterized. Photooxidation occurred even if unsensitized, while photoalteration was very slow in the absence of oxygen. The main oxygenated-products 3 and 13 were also recovered under biomimetic conditions by exposure of an aqueous solution of 1 to sunlight. 相似文献
778.
779.
Marlies H?rdtlein Martin Kaltschmitt und Iris Lewandowski 《Umweltwissenschaften und Schadstoff-Forschung》1998,10(3):135-140
Zusammenfassung Teil I gibt einen überblick über den Ursprung und die Entwicklung des Begriffes “Nachhaltigkeit” im allgemeinen und für die
Landwirtschaft im speziellen. Demnach wird Nachhaltigkeit zwar unter ?kologischen, sozialen und ?konomischen Aspekten diskutiert;
eine allgemein anerkannte Definition des Begriffes existiert bisher jedoch weder für die jeweiligen Einzelaspekte noch unter
Zusammenführung aller drei Aspekte. Dies erschwert die Ermittlung und Umsetzung der Nachhaltigkeit in der Praxis.
Ausgehend von der Begriffsentwicklung und den wesentlichen heute definierten Begriffsinhalten wird deshalb für eine nachhaltige
Pflanzenproduktion aus prim?r ?kologischer Sicht eine Definition vorgeschlagen. Sie dient als Grundlage für einen methodischen
Ansatz, der eine Operationalisierung und damit eine Umsetzung der Nachhaltigkeit der Pflanzenproduktion in der Praxis erm?glichen
soll (?Teil II).
相似文献
780.
Topcu S Incecik S Unal YS 《Environmental science and pollution research international》2003,10(1):24-32
Istanbul has faced serious air pollution problems since the mid-80s. This is mainly due to particulate air pollution coming from poor quality lignite in areas, which are heavily populated and industrialized. As a consequence of severe air pollution problems, stringent control on the emissions in the city started in the year of 1994. In this work, in order to study the relationship between emissions and meteorological conditions, an assessment of air pollution episodes and air pollution potential in the city is presented for the terms at the changed emission schedule as the influence of an emission reduction strategy. The influence of meteorological conditions on the TSP (total suspended particulates) levels is considered for two consecutive winter periods. On this occasion, the city has faced different TSP levels and episode characteristics depending on stringent emission reductions covering the banned, poor-quality lignite and fuel switching. For this purpose, climatological conditions and air quality analyses were performed. 相似文献