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低温条件下满江红对地表水氮磷的去除效应研究 总被引:1,自引:0,他引:1
在冬季低温条件下研究了利用固氮植物满江红对模拟的不同磷浓度地表水的氮磷去除效应。结果表明,在各种磷浓度下,满江红对铵态氮、硝态氮和可溶性磷均有较好的去除效果,在试验结束的时候,溶液铵态氮、硝态氮去除率分别达94.04%和95.46%以上。磷的去除率随污染水体磷水平提高而增加,在处理前水体磷污染水平分别为0.1,0.4,1.6 mg P/L的条件下,其去除率分别达到87.0%,96.8%,99.0%。在磷污染水平提高时,满江红的生长量均有增加。满江红的生长量、植物体氮和磷浓度均随水体中磷的水平增加而提高。研究表明,满江红对富营养化地表水营养盐去除效果较好,可作为富营养化地表水修复植物。 相似文献
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在冬季低温条件下研究了利用固氮植物满江红对模拟的不同磷浓度地表水的氮磷去除效应。结果表明,在各种磷浓度下,满江红对铵态氮、硝态氮和可溶性磷均有较好的去除效果,在试验结束的时候,溶液铵态氮、硝态氮去除率分别达94.04%和95.46%以上。磷的去除率随污染水体磷水平提高而增加,在处理前水体磷污染水平分别为0.1,0.4,1.6 mg P/L的条件下,其去除率分别达到87.0%,96.8%,99.0%。在磷污染水平提高时,满江红的生长量均有增加。满江红的生长量、植物体氮和磷浓度均随水体中磷的水平增加而提高。研究表明,满江红对富营养化地表水营养盐去除效果较好,可作为富营养化地表水修复植物。 相似文献
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水体氮浓度对狐尾藻和金鱼藻片段萌发及生长的影响 总被引:2,自引:0,他引:2
为了厘清水体氮浓度对沉水植物片段萌发及生长的影响,通过模拟控制试验,设计了水体总氮浓度分别为0 (CK)、 0.5 mg/L (N1)、 2 mg/L (N2)、 8 mg/L (N3)和12 mg/L (N4)共5个处理,研究了水体不同氮浓度条件下狐尾藻 (Myriophyllum spicatum) 和金鱼藻 (Ceratophyllum demersum)片段(3节)萌芽数、 萌发位置、 芽长和生物量的差异。结果表明, 水体氮浓度对不同沉水植物片段萌发的影响存在差异,较高的水体氮浓度不利于狐尾藻片断萌发,而对金鱼藻片段却有一定程度的促进;氮浓度处理促进了狐尾藻顶端优势,却抑制了金鱼藻的顶端优势。狐尾藻以0.5 mg/L处理的芽长较长,生物量以2 mg/L处理最大;而金鱼藻以8 mg/L处理芽长最长,生物量以2 mg/L处理最大。由此可见,不同沉水植物对水体氮适应性存在差异,水体氮浓度较低时,沉水植物断枝可以进行萌发和生长, 而当氮浓度超过2 mg/L时,对沉水植物断枝萌发及生长反而有抑制作用;金鱼藻片段比狐尾藻对水体氮浓度的耐受性强。 相似文献
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滇池宝象河流域水体氮素特征及影响因素 总被引:2,自引:1,他引:1
非点源流失的氮是造成水体污染的主要因素之一.通过对滇池宝象河6个点位沟渠水和河道水体氮素的动态监测,研究了流域水体氮污染特征和影响因素.结果表明,农田沟渠水总氮平均浓度高于相应河道水总氮浓度,沟渠水总氮平均浓度范围为3.86~22.86 mg/L,河道水总氮浓度3.14~6.63 mg/L,总体趋势是从上游到下游水体氮素浓度逐渐升高、并且沟渠水体和河道水体氮素随时间变化呈现同样的趋势.农田沟渠水与河道水体总氮之间、农田沟渠水总氮与沟渠周边表层土壤全氮及沟渠沉积物全氮均呈显著相关性. 相似文献
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不同氮形态对铅胁迫下苏丹草根系形态及铅吸收富集特征的影响 总被引:1,自引:0,他引:1
为进一步研究富营养化水体中不同氮形态和重金属对修复植物的交互作用,通过水培试验研究了水体中不同形态氮培养对铅胁迫下苏丹草根系形态及其对铅吸收富集的影响。结果表明,水体Pb(0.5mmol/L)污染时,不同氮形态培养虽然对苏丹草根系形态有一定的影响,但没达到显著性差异,然而对苏丹草根系中丙二醛(MDA)含量及其各器官生物量的影响达显著差异(p<0.05),NH4—N营养液培养的苏丹草根系MDA含量比NO3—N,NO2—N营养液培养的分别高出了4.6和1.6倍;NO3—N营养液培养的苏丹草根、茎、叶生物量比NH4—N营养液培养的分别高出了28.7%,19.6%和23.9%,比NO2—N营养液培养的高出37.6%,30.9%和36.7%。水体Pb(0.5 mmol/L)污染时,NO3—N营养液培养的苏丹草根中Pb浓度明显比NH4—N营养液培养的高出2倍多,且其地下富集系数最大;NO2—N营养液培养的苏丹草茎中Pb浓度明显比NH4—N营养液培养的高出近8倍,且其对铅的转运能力影响作用最强。这表明受重金属污染的富营养化水体中如存在不同形态氮,在一定程度上还有利于削弱重金属对修复植物的毒性作用,增大水体对某些重金属的环境容量。 相似文献
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水体氮的时空变化及其与藻类生长的关系对研究水体富营养化具有十分重要的作用。采用GPS定位,对滇池海埂、斗南、罗家村、新街、昆阳5个代表性位点断面水体总氮、铵态氮、硝态氮及叶绿素a含量进行了为期1a的监测和动态研究,全面分析了不同区域、不同层次、不同时期滇池水体各形态氮的时空变化特征及其对藻类生长的影响。结果表明,全湖各采样点水体总氮、铵态氮、硝态氮的平均浓度分别是2.14、0.11、0.20mg·L-1,全年分别在0.66~6.44mg·L-1、0~0.74mg·L-1、0~0.94mg·L-1之间变化。各区域水体总氮的浓度以海埂和斗南最高,铵态氮和硝态氮的变化幅度较大。全湖水体总氮和铵态氮与叶绿素a呈显著正相关,硝态氮与叶绿素a呈负相关趋势;滇池不同区域水体总氮与叶绿素a呈显著正相关,海埂和罗家村位点水体铵态氮与叶绿素a呈显著正相关,海埂位点水体硝态氮与叶绿素a呈显著负相关,其他区域则无显著相关性;水体总氮、铵态氮、硝态氮对藻类生长的影响呈现显著的区域性和水层差异。 相似文献
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滆湖氮污染双同位素溯源与清单统计法对比研究 总被引:3,自引:0,他引:3
滆湖位于我国江苏省,湖区主要涉及常州市的武进区、金坛区以及无锡市的宜兴市。密集的人口和发达的工农业造成滆湖水体中的氮素污染严重,污染来源复杂。因此亟待识别水体中的氮素污染来源,为氮素污染治理提供数据参考。本研究以生活污水、化学肥料及工业废水为硝态氮端元,借助氮氧同位素端元混合模型计算出滆湖区域生活污水、化学肥料及工业废水对滆湖硝态氮污染负荷贡献率,分别为22.79%、33.25%、43.96%。同时本研究针对2013年整年滆湖区域调研数据,利用清单统计法,从宏观上量化了一整年3种来源硝态氮负荷贡献量的绝对值,并推算出相对值,分别为42.09%、48.11%、9.80%。两种方法以互补的方式对不同时间尺度上滆湖硝态氮污染负荷进行了表征,为滆湖硝态氮污染的治理提供了科学参考。 相似文献
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太湖地区地表水氮污染源的评论 总被引:11,自引:0,他引:11
The nitrogen (N) pollution status of the 12 most important rivers in Changshu, Taihu Lake region was investigated. Water samples were collected from depths of 0.5-1.0 m with the aid of the global positioning system (GPS). The seasonal variations in the concentrations of different N components in the rivers were measured. Using tension-free monolith lysimeters and ^15N-labeled fertilizer, field experiments were carried out in this region to determine variations of iSN abundance of NO3^- in the leachate during the rice and wheat growing seasons, respectively. Results showed that the main source of N pollution of surface waters in the Taihu Lake region was not the N fertilizer applied in the farmland but the urban domestic sewage and rural human and animal excreta directly discharged into the water bodies without treatment. Atmospheric dry and wet N deposition was another evident source of N pollutant of the surface waters. In conclusion, it would not be correct to attribute the N applied to farmlands as the source of N pollution of the surface waters in this region. 相似文献
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长江三角洲地区地表水污染的模式与对策 总被引:4,自引:1,他引:4
On the basis of field investigations, observations and experimental data combined with environmental monitoring information, the status and the spatial and temporal patterns of surface water pollution over thepast ten years in the Yangtze River Delta have been assessed. The water quality of large rivers is still verygood but most of the medium-sized and small rivers have been very seriously polluted. The appearance of black and odorous conditions in rivers in the urban areas has increased due to serious pollution by organic matter with consequent high oxygen demand. Annual increases in N and P concentrations in lakes haveaccelerated eutrophication. The water quality of rivers in small towns is rapidly deteriorating. The mainsources of surface water pollution include industrial and domestic sewage, animal manures, chemical fertilizersin farmland, and polluted sediments in rivers and lakes.Counter measures against these sources of pollution are presented. Regional laws and regulations for protection of surface waters and their enforcement are urgently required. A regional water environmental management agency should be established. The construction of sewage treatment plants of varying capacity must be accelerated to increase the proportion of sewage treated and to improve the quality of treated effluent. Animal wastes must be recycled effectively and efficiently, and the application rates of fertilizers and manures must be balanced with crop nutrient requirements to prevent diffuse pollution from agriculture. The comprehensive rehabilitation of medium-sized and small rivers should be intensified, and the delimitation and protection of the areas used as sources of drinking water should be strengthened. 相似文献
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云南山区农业面源污染控制微区域集水系统技术体系 总被引:1,自引:1,他引:1
面源污染已成为造成河流、湖泊、水库污染的主要原因,有效控制面源污染对于改善水环境质量具有十分重要的意义。针对云南山区面源污染的现状,通过分析面源污染形成的原因和治理中存在的问题,认为微区域集水系统具有拦截和控制山区坡耕地地表径流、增强山坡水源涵养功能和控制农田径流等多项功能,能够实现生态治污、有效控制面源污染的目的。 相似文献
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Roberta Bettinetti Silvana Galassi Silvia Quadroni Pietro Volta Fabrizio Capoccioni Eleonora Ciccotti Giulio A. De Leo 《Water, air, and soil pollution》2011,217(1-4):321-331
One of the aims of the Water Framework Directive 2000/60/CE is to assess the ecological status of water bodies in Europe in relation to priority contaminants, including some persistent organic pollutants (POPs). Recognizing the benefits of measuring hydrophobic compounds in biota tissues rather than in water, we used the European eel Anguilla anguilla in the present study as a bioindicator species for monitoring POPs in freshwater/brackish environments. We present the results of a contamination analysis of eels carried out in three Italian sites representative of different pollution levels: the last part of Tevere River, which flows through a very urbanized and industrialized area, Caprolace Lake and Lesina Lagoon, inside two different protected national parks. A very high pollution variability was recorded within each group of eels, in particular for those caught at Caprolace Lake. Due to this high variability, inter-population comparisons were carried out only between eels collected in Tevere River and Lesina Lagoon. PCBs values in Lesina Lagoon were two orders of magnitude lower than those measured in Tevere River, while no significant differences were found for levels of DDT compounds. Our results confirm the suitability of the eel as an indicator of persistent bioaccumulative pollutants in brackish environments and rivers where it can be easily caught, but we are sceptical of its use in deep lakes where its capture might be problematic considering standard operation procedures for fish sampling. 相似文献
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太湖水体富营养化的重要驱动之一是流域上游区域的氮磷流失。圩区作为太湖上游平原区域的主要地理单元,具有复杂的水文与氮磷流失过程。针对圩区科学氮磷识别与高效管控是太湖治理的关键。本研究以太湖上游平原圩区为研究对象,采用氮动态模型(Nitrogen Dynamic model for lowland Polder systems,NDP)和磷动态模型(Phosphorus Dynamic model for lowland Polder systems,PDP)模拟圩区氮磷流失的动态过程,并基于圩区氮磷流失机制进行管理情景定量模拟与氮磷减污效益分析。结果表明:1)圩区氮磷的年平均流失强度分别为40和1.75 kg/ha/yr,高于太湖流域的平均氮磷流失水平;2)当圩区外部水质控制为Ⅳ类时,氮磷流失强度分别为37.54和1.58 kg/ha/yr,圩区截流氮磷量分别增加4.9%和9.9%,高氮磷流失级别的圩区数量分别减少26.2%和63.8%;3)如将圩区内5%的水田转化为水体,氮磷流失强度分别为36.73和1.72 kg/ha/yr,圩区截流氮磷量分别增加6.6%和1.7%,高氮磷流失级别的圩区数量分别减少46.2%和22.5%;4)圩区氮磷的流失机制具有明显不同,圩外水质目标对于圩内磷的流失影响较大,圩内的水体和坑塘等对于氮滞留和净化更加有优势。 相似文献
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农田氮、磷随地表径流向水体迁移,不仅造成化肥利用率降低,农业生产成本上升,还对水环境造成污染,引起水体富营养化。针对滇池流域规模化韭菜生产施肥量大,农业面源污染严重等问题,采用田间试验,结合自然降雨与人工模拟降雨,研究了不同施肥及田间沟渠利用方式下农田氮、磷的流失风险。结果表明,相对于化肥表施,合理的有机-无机肥料配合施用以及化肥深施,可分别降低地表径流中总氮和总磷平均浓度53%和39%。施肥后1周为氮、磷流失的高风险期,随后其风险随时间延长而降低;通过小区问沟渠的改造,提高排水溢流口高度,控制径流在沟渠内滞留时间以及采用农田养分循环利用的回灌技术,可减少农田向环境水体输出总径流量的76%以上,并同时提高了肥料利用率。 相似文献
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冻融作用引起水土流失,造成磷分等无机污染物流到下游江河湖泊等水体,引起非点源污染,造成土壤肥力下降、生态环境恶化等问题。首先从农田土壤磷分、植物体内磷分以及微生物生物量磷3方面介绍冻融作用对磷分转化迁移的影响;然后对冻融作用磷流失的防治提出增施有机肥、合理密植、恢复并改良植被、封育、退耕还林(草)等建议;最后,提出我国未来冻融作用对磷分转化迁移研究在土壤磷分水平、垂直方向上迁移转化机制,植物体内磷分迁移转化机制,微生物生物量磷迁移转化机制,以及冻融过程磷分流失模型方面提出研究展望。 相似文献
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In this study, we constructed aquatic microcosms, including four experimental groups, to simulate eutrophic lakes. Using polyurethane sponges as artificial substrates to support periphyton, we conducted a systematic study of the effect of periphyton on the water quality of eutrophic lakes by monitoring water-quality indexes including TN, TP, and NTU. The results show that periphyton can effectively degrade N and P in these bodies of water, reduce NTU and the concentration of Chl-a, and restore the aquatic environment. Periphyton can also promote the formation of the DO-Chl-a-NTU-TN-TP synergistic system, which can provide a basis for the comprehensive management of eutrophic lakes. Periphyton can also effectively improve the water quality of eutrophic lakes, and its positive impact on lake ecosystems cannot be ignored during the treatment of eutrophic lakes. 相似文献
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流域沟渠植草拦截农田氮磷入河污染的有效性研究 总被引:2,自引:1,他引:1