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581.
生物监测及其在环境监测中的应用(Biological Monitoring and Its Application in Environmental Monitoring) 总被引:7,自引:0,他引:7
生物监测是近几十年来发展起来的应用于环境监测领域的一门新兴技术,是指利用生物个体、种群或群落对环境污染或变化所产生的反应,从生物学角度对环境污染状况进行监测和评价.作为环境监测的重要组成部分,生物监测具有敏感性、长期性、连续性、经济性、非破坏性和综合性等优势,有望在生态系统环境监测、总量控制、环境风险评价、环境污染早期预警、突发事件监测和环境标准制定等领域取得突破.在总结国内外相关研究的基础上,从目前在环境监测中应用的生物监测的原理、分类、特点、方法学和实际应用等方面进行综述.尽管生物监测还有不足之处,但可以肯定,其发展和应用将会对环境监测事业产生极大的推动作用,有着非常广阔的发展前景. 相似文献
582.
The use of the organic As compound, roxarsone, as an antibiotic additive to poultry feed continues to raise concern over potential negative environmental impacts. Total As concentration in poultry litter can reach >40 mg kg−1 and both roxarsone and its mineralization product As(V) have been identified in poultry litters (PL). To investigate the fate of these As species upon land application of PL we conducted two studies. In the first, an Orangeburg soil (Ultisol from the Atlantic Coastal Plain) was spiked with either 20 mg kg−1 As(V) or roxarsone and incubated at 10% moisture content for 4 months. Exchangeable As was determined periodically by extraction with 0.1 M PO4. Both As(V) and roxarsone displayed similar desorption; initially, approximately 70% of added As was ligand exchangeable and this decreased to 35% after 4 months incubation, presumably due to either slow sorption reactions or a change in solid phase speciation of As to less exchangeable forms. In the second study, various manipulations of two PL samples were applied to the Orangeburg soil at realistic field application rates. The treatments were wet to 10% moisture content and water soluble As, Cu and organic carbon (DOC) was measured over 30 days. Arsenic and Cu solubility were highest from the dried litter samples. Ashing of the PLs decreased soluble As and Cu, presumably because of the loss of organic matter from the ashed litter and subsequent decrease in DOC. Application of leachates from either PL resulted in higher concentrations of soluble As and Cu than when the soil was amended with equivalent concentrations of soluble As and Cu dissolved in DI H2O. We hypothesize that the increased levels of DOC from the PL treatments enhance As and Cu solubility through competitive sorption and complexation, respectively. In fact, As and Cu solubility was correlated to DOC levels in the amended soil extracts. Even though land application of PL introduced relatively low concentrations of As and Cu to soil it appeared that other soluble constituents of PL significantly enhanced As and Cu solubility. 相似文献
583.
Derivation of predicted no effect concentrations (PNEC) for 2,4,6-trichlorophenol based on Chinese resident species 总被引:4,自引:0,他引:4
2,4,6-Trichlorophenol (2,4,6-TCP) is a common chemical intermediate and a by-product of water chlorination and combustion processes, and is a priority pollutant of the aquatic environment in many countries. Although information on the toxicity of 2,4,6-TCP is available, there is a lack of information on the predicted no-effect concentration (PNEC) of 2,4,6-TCP, mainly due to the shortage of chronic and site-specific toxicity data. In the present study, acute and sub-chronic toxicity of 2,4,6-TCP on six different resident Chinese aquatic species were determined. PNEC values were calculated and compared by use of two approaches: assessment factor (AF) and species sensitivity distribution (SSD). Values for acute toxicity ranged from 1.1 mg L−1 (Plagiognathops microlepis) to 42 mg L−1 (Corbicula fluminea) and the sub-chronic no observed effect concentrations (NOECs) ranged from 0.05 mg L−1 (Mylopharyngodon piceus) to 2.0 mg L−1 (C. fluminea). PNECs obtained by the assessment factor approach with acute (AF = 1000, 0.001 mg L−1) or chronic (AF = 10, 0.005 mg L−1) toxicity data were one order of magnitude less than those from SSD methods (0.057 mg L−1). PNEC values calculated using SSD methods with a 50% certainty for 2,4,6-TCP was less than those obtained by use of the USEPA recommend final chronic value (FCV) method (0.097 mg L−1) and the one obtained by use of the USEPA recommend acute-to-chronic (ACR) methods (0.073 mg L−1). PNECs derived using AF methods were more protective and conservative than that derived using SSD methods. 相似文献
584.
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587.
钝化与叶面阻控对不同基因型红菜苔镉累积的影响 总被引:2,自引:0,他引:2
为探索中轻度重金属镉(Cd)污染农田安全利用技术,实现农产品安全生产,以两种不同镉累积基因型红菜苔为供试作物,采用盆栽试验的方法,分别于两种作物上设置相同的6个处理:对照(CK)、添加3%(质量分数)生物质炭(BC)、添加0.17%钙镁磷肥(CMP)、叶面喷施3 mg·L~(-1) Na_2SeO_3的水溶液(Se)、 BC+Se和CMP+Se,研究不同处理土壤镉有效性变化及植株不同部位镉累积特征.结果表明:①相同处理下,低镉累积基因型金秋红三号红菜苔根部土壤有效态镉含量均显著低于高镉累积基因型十月红.BC和CMP两种钝化剂对金秋红三号根部土壤中的镉钝化效果显著,且BC效果更佳,钝化处理的效果显著优于叶面阻控.②金秋红三号红菜苔根系较十月红对镉有更强的富集能力,其富集的镉倾向于囤积在根部.叶面施硒与两种钝化剂对抑制镉向红菜苔可食部位转移富集无协同效果.③在BC和CMP钝化处理下,金秋红三号红菜苔可食部位镉含量低于GB 2762-2017中镉限量值(0.10mg·kg~(-1)).本研究表明,针对中轻度镉污染农田土壤,通过施加生物质炭、钙镁磷肥等绿色钝化剂,种植弱吸收低积累作物品种,可以实现受镉污染农田的安全利用和农产品的安全生产. 相似文献
588.
Production and application of a novel bioflocculant by multiple-microorganism
consortia using brewery wastewater as carbon source 总被引:11,自引:0,他引:11
The flocculating activity of a novel bioflocculant MMF1 produced by multiple-microorganism consortia MM1 was investigated. MM1 was composed of strain BAFRT4 identified as Staphylococcus sp. and strain CYGS1 identified as Pseudomonas sp. The flocculating activity of MMF1 isolated from the screening medium was 82.9%, which is remarkably higher than that of the bioflocculant produced by either of the strains under the same condition. Brewery wastewater was also used as the carbon source for MM1, and the cost-effective production medium for MM1 mainly comprised 1.0 L brewery water (chemical oxygen demand (COD) 5000 mg/L), 0.5 g/L urea, 0.5 g/L yeast extract, and 0.2 g/L (NH4)2SO4. The optimal conditions for the production of MMF1 was inoculum size 2%, initial pH 6.0, cultivating temperature 30℃, and shaking speed 160 r/min, under which the flocculating activity of the MMF1 reached 96.8%. Fifteen grams of purified bioflocculant could be recovered from 1.0 L of fermentation broth. MMF1 was identified as a macromolecular substance containing both protein and polysaccharide. It showed good flocculating performance in treating indigotin printing and dyeing wastewater, and the maximal removal efficiencies of COD and chroma were 79.2% and 86.5%, respectively. 相似文献
589.
北京市畜禽粪便土地利用适宜性分析 总被引:4,自引:0,他引:4
以北京市为研究区域,基于GIS下采用权重线性加和模型(WLC),综合自然、环境、社会和经济等多因子.对北京市畜禽粪便土地利用的适宜性进行了定量分析.结果表明,北京市10个郊区县适合施用畜禽粪便的耕地面积为1605.3 km2,占耕地总面积的35.3%,主要分布在北京市的南部、东南部和中部地区.聚类分析将全市郊区划分为东南部、北部、西南部和中部4个区域.东南部和中部远郊平原区比较适合发展畜禽养殖业,目前的养殖量与最大承载量之间尚存在一定空间;但是由于城镇化的加快,可施用粪便的农田与居民区的安全距离成为影响粪便施用的主要因素,需要结合有效的管理措施以避免畜禽粪便土地利用的污染风险.北部和西南部远郊低山丘陵区应适度控制畜禽养殖业的发展,由于北部区县(延庆、怀柔、密云和平谷)河流密集,并分布有北京市的主要地表水源,故与水体的安全距离对该地区的耕地施用粪便有重要影响;应控制和减少土壤沙化及水土流失,同时建立滨岸缓冲带来控制畜禽粪便土地利用对水体的进一步污染,以达到经济发展和环境保护的双重目的. 相似文献
590.
水稻光合碳是稻田土壤有机碳的重要来源之一,其在土壤中输入与分配特征受水稻生长状况和土壤肥力的影响.施肥是影响水稻生长的关键因素,为了探讨施氮对水稻拔节期光合碳的传输动态的影响,应用稳定同位素13C-CO2脉冲标记技术,通过盆栽试验,研究光合碳在水稻-(根际/非根际)土壤系统中输入与分配的动态变化及其对施氮的响应.结果表明,施氮显著增加了水稻地上部和根系生物量,降低了水稻根冠比.随着水稻的生长,水稻植株的13C丰度逐渐下降,根际土和非根际土中13C丰度先减少再增加;施氮显著增加了根际土壤中13C丰度,较不施氮相比增加了9.5%~32.6%.施氮使水稻地上部和根系中光合13C含量显著增加,较不施氮处理分别增加了24.5%~134.7%和9.1%~106%.脉冲标记一次性输入的光合13C主要分配在水稻植株体内,不施氮和施氮条件下的分配率分别为85.5%~93.2%和91.3%~95.7%;施氮显著影响光合碳在水稻地上部、根际土和非根际土中的分配特征(P0.01),标记后26 d,与不施氮处理相比,施氮使光合碳在水稻地上部的分配增加了13.4%,在根际土和非根际土中的分配分别减少了21.9%和52.2%.因此,施氮增加了光合碳在土壤-水稻系统中的分配,但降低了光合碳在土壤中的累积.本研究进一步探讨了施氮条件下水稻拔节期光合碳的分配,为明确氮素对光合碳在水稻拔节期的动态变化以及对土壤有机碳库的影响,和深入了解农田土壤有机质累积提供理论依据和数据支持. 相似文献