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内源磷的释放作用及影响因素研究进展 总被引:1,自引:0,他引:1
水体的富营养化已成为目前环境研究中的焦点问题,磷在湖泊中的浓度高低是衡量湖泊富营养化水平的重要指标,是水生态系统基本营养盐之一,并且是淡水湖泊的最主要限制性营养因子。在外源磷得到有效的控制之后,内源磷的污染仍然能够保持湖泊的富营养化状态,此时内源磷的控制就成为了难点和重点。在底泥中的结合态磷,主要是以无机磷和有机磷的形式存在,有机磷与微生物活性密切相关,无机磷则主要与底泥存在的环境联系紧密。湖泊底泥内源磷释放受到一系列物理、化学、生物过程的控制,其影响因素主要包括扰动、氧化还原电位、pH值等,是多种因子综合作用的结果,同时,扰动引起的底泥再悬浮对内源磷有吸附固定作用。故底泥内源磷的释放机理有待进一步探索,在多种影响因素作用下,进一步研究底泥再悬浮对磷的吸附释放作用,从而明确内源磷的主要来源及吸附释放过程,为内源磷的控制提供理论依据,进而控制水体富营养化。 相似文献
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《中国环境管理干部学院学报》2004,(3)
最新研究表明,洗涤剂中的磷对水体的富营养化有影响,但不是主导影响,更不是水体富营养化的惟一凶手。 中国科学院地理与湖泊研究所以太湖为例,就洗衣粉排磷对湖泊磷负荷的贡献率进行了定量调查,经过两年的调查和试验,得出了太湖流域地区各种途径对太湖流域水体磷的贡献率依次为:人体(粪便)排磷43.57%、洗衣排磷16.1%、畜禽排磷12.51%、农业(化肥流失)排磷11.89%、工业(污染)排磷7.41%、水产养殖排磷5.3%、其他排磷2.8%。 相似文献
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水体富营养化问题评述 总被引:30,自引:2,他引:28
磷是水体富营养化问题产生的一个重要的原因。本文对磷污染产生的原因进行了调查 ,分析了各种污染的相对重要性 ,在此基础上对富营养化问题的预防和治理措施进行了综合分析和论述 ,指出解决富营养化问题应坚持预防为主 ,防治结合的原则。 相似文献
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富营养化是指一种过程,在这一过程中,植物营养元素磷的增加与氧的锐减将导致湖泊生态系统发生一系列剧变。富营养化亦可被定义为生态系统中有机质输入速率增加的过程。从上述两方面的意义上讲,有机质的分解必然伴随生物可利用性磷的再生,从而对富营养化过程产生有效的反馈。本文扼要概述了上述反馈途径及其生态风险,即水体沉积物磷释放的原始驱动力来自有机质的分解,其主要途径包括自身的矿化与厌氧状态促成之后磷酸盐的解吸附。微生物群落将依有机质的数量和性质在分解过程的不同阶段发生明显变化,从而形成因时因地而异的分解速率与还原力,二者共同促进沉积物磷的释放,因高分解速率伴随高缺氧程度,且源于沉积物之长期库存,磷酸盐的解吸附量并非简单正比于有机质含量,而可能远大于此,换言之,有机质的大量输入与沉积可能导致生物有效性磷的净增,水体富营养化程度将因此而以正反馈的形式加剧。在倡导和推行有机农业的过程中,应充分注意并严格控制土壤有机质的流失。 相似文献
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利用大型水生植物控制水体富营养化是一种很有前景的生态修复技术。本文从大型水生植物对藻类的抑制作用和对水体中氮、磷的去除作用2方面综述了相关研究,并对今后的研究进行了展望。 相似文献
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国内外学者在湖泊水环境方面开展了大量的研究,然而主要集中在各种形态氮、磷等营养盐上,对有机质的来源、循环及生态学效应的研究比较缺乏。近期研究表明:有机质是水体及沉积物中的重要组分,沉积物中有机质可经分解、矿化,释放到上覆水体,重新进入营养循环;同时,有机质对重金属及有机污染物的迁移转化有着重要影响。本文简要分析了湖泊有机质已有的研究进展,论述了有机质在湖泊水环境中的重要作用、主要技术突破及难点,指出有机质研究对水环境质量评价、污染控制和生态修复都具有重要意义。研究表明,开展有机质在水环境中循环转化、生物有效性及其与富营养化之间关系的研究,将是湖泊水环境研究领域未来的主要研究方向之一。 相似文献
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我国是世界上人口最多、洗涤剂用量巨大、水系丰富、水域富营养化问题突出的国家,也是世界上需要禁磷的国家。但由于种种原因,国内目前对洗涤剂的"禁磷"问题存在很大争议。近段时间来,太湖等水域出现了严重的环境危机。本文在介绍国内外有关洗涤剂"禁磷"概况的基础上,就防治水域富营养化及我国洗涤剂"禁磷"的问题进行了分析讨论,指出在水体富营养化的综合整治中,严格、完全禁磷是最重要的措施。 相似文献
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R. Walter. Ogburn Patrick L. Brezonik Joseph J. Delfino 《Journal of the American Water Resources Association》1987,23(5):829-831
ABSTRACT: Laboratory microcosms were used to evaluate the effect of pH on release of soluble reactive phosphorus (SRP) during aerobic decomposition of the aquatic macrophyte Eleocharis sp., which is common in oligotrophic Florida lakes. The total amount of SRP released during a 227-day incubation in the dark was independent of pH over the range 3.7 to 5.5, but initial rates of release were faster at the lowest pH. The results indicate that the low total phosphorus concentrations observed in many acidic lakes are not necessarily attributable to reduced rates of decomposition and nutrient mineralization at low pH, as some researchers have suggested. 相似文献
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Spencer A. Peterson 《Journal of the American Water Resources Association》1982,18(3):423-436
ABSTRACT: Fresh water lake sediment removal is usually undertaken to deepen a lake and increase its volume to enhance fish production, to remove nutrient rich sediment, to remove toxic or hazardous material, or to reduce the abundance of rooted aquatic plants. Review of more than 60 projects and five case histories reveals that the first three objectives are usually met through sediment removal. Dredging to control aquatic plants has not been well documented. Disadvantages of dredging include cost, temporary phosphorus release from sediment, increased phytoplankton productivity, noise, lake drawdown, temporary reduction in benthic fish food organisms, the potential for toxic material release to the overlying water and potential for environmental degradation at the dredged material disposal site. The technique is recommended for deepening and for long range reduction of phosphorus release from sediment. Sediment removal to control toxic materials is possible with minimal environmental impact when proper equipment is used, but it may more than double the cost. Lack of definitive information about rooted plant regrowth rates in dredged areas prohibits explicit recommendations on sediment removal to control plant growth. 相似文献
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一些常见的沉水草本植物对水质具有较强的净化作用,能够有效控制氮和磷的浓度.本试验通过模拟氮、磷污染的水质条件,采用篦齿眼子菜对氮、磷营养盐的吸附和去除效果进行研究.结果 表明:设定模拟废水中的初始总氮(TN)浓度在1~50 mg/L范围内,培养30天后的植株对总氮的去除率最高可达85.4%,随着初始培养环境中总氮浓度的... 相似文献
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Hosung Ahn 《Journal of the American Water Resources Association》1999,35(2):301-310
ABSTRACT: Atmospheric deposition can be a significant source of phosphorus to South Florida's aquatic system. Deposition samples are often contaminated to varying degrees by bird droppings or other foreign materials. This study attempted to use statistical and other methods to detect and remove the outliers in the rain-borne total phosphorus concentration data. Some outliers in the data were identified using field notes derived from visual inspection of the samples. Outlier detection statistics based on a simple linear regression were then used for additional data screening. As a result of these analyses, about 35 percent of the observed values were identified as outlying data which needed to be removed prior to further data analyses. Based on detected outliers in the data from 15 monitoring sites, a lumped cutoff value of 130 4mUg/L was determined. This lumped cutoff value may be useful for further quality control and analyses of the data from the region. 相似文献
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James M. Omernik David P. Larsen Christina M. Rohm Sharon E. Clarke 《Environmental management》1988,12(6):815-825
A map of summer total phosphorus in lakes has been compiled for Minnesota, Wisconsin, and Michigan to clarify regional patterns in attainable lake trophic state. Total phosphorus was used as a measure of lake trophic state because: (1) phosphorus plays a central role in controlling the overall fertility of most lakes, (2) total phosphorus values are available for a great number of lakes, and (3) phosphorus is measured in a consistent manner. The maps were compiled using patterns of total phosphorus data and observed associations between these data and geographic characteristics including physiography, land use, geology, and soils. Regions depicted on the map represent areas of similarity in phosphorus concentrations in lakes, or similarity in the mosaic of values, as compared to adjacent areas. Within each region, differences in total phosphorus can be compared to natural and anthropogenic factors to determine the types of lakes representative of each region, the factors associated with differences in quality, and the realistically attainable phosphorus levels for each type of lake. 相似文献
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ABSTRACT: Surface water quality data are routinely collected in river basins by state or federal agencies. The observed quality of river water generally reflects the overall quality of the ecosystem of the river basin. Advanced statistical methods are often needed to extract valuable information from the vast amount of data for developing management strategies. Among the measured water quality constituents, total phosphorus is most often the limiting nutrient in freshwater aquatic systems. Relatively low concentrations of phosphorus in surface waters may create eutrophication problems. Phosphorus is a non-conservative constituent. Its time series generally exhibits nonlinear behavior. Linear models are shown to be inadequate. This paper presents a nonlinear state-dependent model for the phosphorous data collected at DeSoto, Kansas. The nonlinear model gives significant reductions in error variance and forecasting error as compared to the best linear autoregressive model identified. 相似文献
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