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1.
以巢湖湖底有机碎屑为研究对象,基于对有机碎屑中总有机碳的测定,研究了利用好氧强化降解湖底有机碎屑.研究了有机碎屑的可生化性及好氧强化降解湖底有机碎屑的效果,并讨论了有机碎屑的浓度及曝气量对其降解效果的影响.结果说明,处理的有机碎屑具有较好的可生化性,在反应30 h左右,降解达到了平衡,总去除率达到了50.69%,降解速率常数K25为0.19 h-1.有机碎屑的浓度以及曝气量对降解效果具有一定的影响.强化好氧法与传统的对底泥处理的方法相比具有更快、更好的效果,为预防及治理水体黑臭现象提供了新的途径. 相似文献
2.
Recycling the large amounts of organic wastes produced by agriculture, forestry, urban and industrial activities as soil, organic amendments are the most popular and efficient option for avoiding their dispersion in the environment and restoring, maintaining, and/or improving the content of soil organic matter. Chemical stability and biological maturity are two important factors for the successful use of organic wastes in agriculture with limited risk for the surrounding environment. Stabilization and maturation of raw organic wastes inherently imply the achievement of an extensive humification, that is, a wide conversion of easily degradable organic matter to refractory organic compounds that resemble native soil humic substances (HS). Soil HS are the most important components of soil organic matter responsible of several soil functions and processes. As a consequence, the amount and quality of HS‐like fractions in any organic amendment are believed to be of primary importance for its agronomic efficacy, environmental safety and economic value. The first part of this review focuses on the chemical and physico‐chemical changes occurring in the humic substances (HS) ‐like fractions of organic wastes of various nature and sources subjected to common treatment processes aimed at producing environmentally‐safe soil amendments with beneficial agronomic properties. The second part discusses the composition, structure, and chemical reactivity of the HS‐like components in organic amendments of various origins and nature, and their effects on native soil HS. The review concludes by highlighting the need for innovative research targeted mainly to achieve a better fundamental understanding of the molecular structure and reactivity of soil HS and HS‐like fractions in organic amendments, the mechanisms of HS formation and transformations in the natural environment and during the treatment processes of raw organic wastes, the interactions with metals and organic xenobiotics, and the direct physiological effects that HS may exert on plants. 相似文献
3.
为探究洪泽湖入湖河流沉积物有机磷的空间分布及外源输入对其形态转化的影响,本文利用Ivanoff法开展有机磷形态特征研究,并通过实验室添加常见外源有机质和铁离子,深入探讨外源物质对沉积物有机磷形态变化的长期影响.研究结果表明,洪泽湖入湖河流沉积物有机磷含量范围为34.8～398.6 mg/kg,占总磷的7.7%～36.9%,其中非活性有机磷(NOP)中活性有机磷(MLOP)活性有机磷(LOP).濉河沉积物LOP平均占比为19.4%,高于其他河流,而成子河NOP平均占比最高,为56.41%,表明有机磷的空间分布不均匀.总体而言,安河和濉河沉积物中总氮、总磷和有机磷含量显著高于成子河和淮河,显示前两条河流有较高的污染水平.冗余分析表明河流沉积物有机磷形态明显受到其理化性质影响,而不同污染程度沉积物的影响因素有所不同.外源物质添加能够活化沉积物的有机磷,促使NOP向LOP和MLOP转化,有机质输入引起的沉积物有机磷形态变化要大于铁元素输入,而外源物质输入对污染较重河流沉积物的有机磷转化作用更为显著.因此,减少入湖河流周边的外源污染排放是减少湖泊生物可利用磷的有效途径. 相似文献
4.
Nikolaus J. Kuhn 《地球表面变化过程与地形》2007,32(5):794-802
The enrichment of organic matter in interrill sediment is well documented; however, the respective roles of soil organic matter (SOM) and interrill erosion processes for the enrichment are unclear. In this study, organic matter content of sediment generated on two silts with almost identical textures, but different organic matter contents and aggregations, was tested. Artificial rainfall was applied to the soils in wet, dry and crusted initial conditions to determine the effects of soil moisture and rainfall and drying history on organic matter enrichment in interrill sediment. While erosional response of the soils varied significantly, organic matter enrichment of sediment was not sensitive to initial soil conditions. However, enrichment was higher on the silt with a lower organic matter content and lower interrill erodibility. The results show that enrichment of organic matter in interrill sediment is not directly related to either SOM content or soil interrill erodibility, but is dominated by interrill erosion processes. As a consequence of the complex interaction between soil, organic matter and interrill erosion processes, erodibility of organic matter should be treated as a separate variable in erosion models. Further research on aggregate breakdown, in particular the content and fate of the organic matter in the soil fragments, is required. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
5.
Peter B. McMahon Don A. Vroblesky Paul M. Bradley Francis H. Chapelle Cheryl D. Gullett 《Ground water》1995,33(2):207-216
Total concentrations of formate, acetate, and isobutyrate varied from less than 5 to greater than 9,000 μmol/l over distances of < 3 m in ground water from a shallow hydrocarbon contaminated aquifer. Laboratory incubations of aquifer material indicate that organic acid concentrations were dependent on the amount of hydrocarbon loading in the sediment and the relative rates of microbial organic acid production and consumption. In heavily contaminated sediments, production greatly exceeded consumption and organic acid concentrations increased. In lightly contaminated sediments rates were essentially equal and organic acid concentrations remained low. Concentrations of dissolved calcium, magnesium, and iron generally were one to two orders of magnitude higher in organic acid-rich ground water than in ground water having low organic acid concentrations. Carbonate and Fe(III)-oxyhydroxide minerals were the likely sources of these elements. Similarly, concentrations of dissolved silica, derived from quartz and k-feldspar, were higher in organic acid-rich ground water than in other waters. The positive relation (r = 0.60, p < .05, n = 16) between concentrations of silica and organic acids suggests that the microbially mediated buildup of organic acids in ground water enhanced quartz/k-feldspar dissolution in the aquifer, although it was not the only factor influencing their dissolution. A model that included organic acid microequivalents normalized by cation microequivalents significantly strengthened the correlation (r = 0.79, p < .001, n = 16) between dissolved silica and organic acid concentrations, indicating that competition between silica and cations for complexation sites on organic acids also influenced quartz/k-feldspar dissolution. Physical evidence for enhanced mineral dissolution in organic acid-rich waters included scanning electron microscopy images of highly corroded quartz and k-feldspar grains from portions of the aquifer containing organic acid-rich ground water. Microporosity generated in hydrocarbon contaminated sediments may adversely affect remediation efforts that depend on the efficient injection of electron acceptors into an aquifer or on the recovery of solutes from an aquifer. 相似文献
6.
由于沉积有机质都存在有自由基，使其具有顺磁性。因此，它可以用于电子顺磁共振的分析和研究。近年来，电子顺磁共振应用于沉积有机质的研究无论在理论方面还是应用方面都有很大的进展。本文主要概述沉积有机质中自由基形成与演化机理及电子顺磁共振在研究有机质成熟度、油气源岩评价和古地温方面的研究现状和主要进展。 相似文献
7.
The effects of sewage organic matter on biogeochemical processes within mid-shelf sediments offshore Sydney, Australia 总被引：2，自引：0，他引：2
G. P. Bickford 《Marine pollution bulletin》1996,33(7-12):168-181
A laboratory incubation experiment was conducted using replicate cores collected from a muddy-sand sediment facies offshore Sydney, Australia to determine what components and processes would be affected by the addition of sewage organic matter. Sewage effluent has a solid phase composition of 40% carbon (35% organic carbon), 5% nitrogen, 1% phosphorus and 5% silicate. The molecular C:N:P ratio is 92:10:1, compared to the Redfield ratio of 106:16:1 in marine phytoplankton. Sediment cores were incubated at in situ temperature in a darkened room for periods up to 95 days. Sewage organic matter was added to the cores at three different loads equivalent to 0 (T0), 65 (T1) and 130 (T2) g m−2 of sediment. Following the addition of sewage organic matter, fluxes of oxygen (into the sediments), ammonia and phosphate (from the sediments) increased, reflecting an enhanced organic carbon supply to the sediments. Oxygen penetrated to a depth of 6 mm in the ambient cores, but the sediment oxygen content was severely depleted following the addition of the sewage-derived organic matter. Sediment porewater data, together with nutrient flux data indicate that oxygen reduction, nitrate reduction and sulphate reduction occurs within these sediments. Following the addition of sewage organic matter, increases in total nitrogen, total phosphate and total organic carbon were measured to depths of 5 cm in the sediments, suggesting that bioturbation influences nutrient and organic carbon distributions. Additionally, irrigation of the surficial sediments may play an important role in the metabolism of organic matter. These results indicate that oxygen penetration, oxygen fluxes, nitrate concentrations within porewaters, ammonia flux rates, and solid phase concentrations of total organic carbon and nutrients may be useful indicators of sediments affected by high rates of organic matter deposition onto Sydney's offshore sediments. The EPA has recently predicted maximum deposition rates of sewage particulate matter to be approximately 1 g m−2 day−1. Because of the similarities in CNP ratios of sewage organic matter and marine organic matter, the effects of sewage organic matter and marine organic matter inputs to coastal sediments may not be easily distinguishable. 相似文献
8.
对于富含有机质的页岩储层来说,孔隙度是评价油气储量的关键参数之一,有机孔隙的存在又对岩石孔隙空间具有重要贡献,因此,研究页岩储层有机孔隙空间是有必要的。本文结合氩离子抛光扫描电镜（SEM）资料和图像分割技术,以川南永川区块YY2井龙马溪组页岩储层为例,对纳米有机孔隙的形态特征和有机孔隙度进行分析研究,研究表明:YY2井龙马溪组有机孔隙较发育,SEM图像中有机孔隙直径差异很大,对龙马溪组6块岩样的SEM图像进行处理,得到的有机质面孔率在0.97％～8.90％之间,个别样品孔径较小,面孔率在1％以下。利用面孔率和有机质含量计算有机孔隙度,计算得到的有机孔隙度在0.12％～0.75％范围内,均值为0.39％,占据岩石孔隙度的10.66％。 相似文献
9.
沉积物中有机质的环境行为研究进展 总被引：57，自引：5，他引：52
水体沉积物是重金属,有毒有机化合物等环境污染物及C,N,P等营养元素的汇和释放源,而有机质对灾些污染物和营养元素在沉积物中的迁移,转化等地球化学行为中起着至关重要的作用,本文就近期有关沉积物中有机质的环境地球化学行为为方面的研究进行了综述,重点评述了有关沉积物中有机质本身的来源,性质,迁移和矿化及其环境效应等方面的研究进展。 相似文献
10.
Radiocarbon dating of Arctic marine sediment is often challenging due to the low availability of calcareous fossils. Consequently, bulk organic matter dating has at times been used to establish sediment core chronologies. Yet, radiocarbon dates based on bulk organic matter often appear to deviate vastly from dates based on fossils, mainly caused by input of allochthounous carbon, including terrigenous organic matter. In this study, we aim to examine the link between the composition of the bulk organic matter and the age offsets between the bulk radiocarbon dates and those obtained from calcareous foraminiferal tests. All samples are taken from the marine sediment core AMD14-204C from offshore Upernavik (eastern Baffin Bay). The radiocarbon dates for bulk organic matter are on average ∼3000 years older than the radiocarbon dates based on foraminifera, but with changing age offsets throughout the record. To investigate the cause of this age offset and its variations over time, we applied core scanning, X-ray Fluorescence analysis, stable isotopes, organic pyrolysis and microscopic organic petrology to examine the distribution and characterization of the organic matter. The results show that the older organic matter includes clastic input of reworked sedimentary rocks potentially originating from West Greenland and/or the Canadian Arctic Archipelago. Changes in the input of contemporary marine algal produced organic matter versus both terrigenous input and reworked ancient organic matter appear to control the age offsets between the bulk and foraminifera dates. A low Hydrogen Index and low δ13Corg values together with a high Oxygen Index, indicative of high influence of terrigenous organic matter, seem to correspond to samples with the largest age offsets; 1000–2000 years greater than in other samples. To examine the cause of the variations in the age offsets, a new quantification of the autochthonous organic matter as a fraction of the TOC was calculated. This shows that samples with the largest age offsets contained the lowest fraction (as low as ∼12%) of autochthonous organic matter in the TOC. 相似文献
11.
HU Kai ZHAI Jianping LIU Yingjun WANG Henian ZHANG Jingrong JIA Rongfen 《中国科学D辑(英文版)》2000,43(5):507-520
The organic matter of three different chronological major carbonaceous rock gold-bearing formations of South China (Middle
Proterozoic Shangqiaoshan group of northeastern Jiangxi, Lower Cambrian Shuikou group of northern Guangxi and Devonian Shetianqiao
group of eastern Hunan) and related carbonaceous stratabound gold deposits such as Jinshan, Longshui and Shixia deposits,
respectively, has been characterized by organic geochemical techniques. These organic geochemical results show that the average
total organic carbon (TOC) content of the three chronological carbonaceous rock gold-bearing formations of South China ranges
from 0.15% to 1.56%. The thermal maturity of the organic matter of host rocks in the three gold-bearing formations is high.
The micro-component of the organic matter of the host rocks consists primarily of solid bitumen and graphite. The organic
carbon and gold of the host rocks appear to syndepositin situ during the formation of the gold-bearing formations. The organic carbon played a certain role in controlling the geochemical
environment of the gold-bearing formations. The metallogenetic mechanism of the carbonaceous rock stratabound gold deposits
of South China is closely associated in genesis with the sedimentation, diagenesis and thermal evolution history of the organic
matter of host rocks in the gold-bearing formations. 相似文献
12.
太湖湖区有机物流失模拟 总被引：7，自引：0，他引：7
研究了１９９２－１９９４年女山湖大面积围栏养蟹利用与保护沉水植物资源的效果结果表明：围栏内河蟹的食物组成中,主要有菹草、苦草、金鱼藻、马来眼子菜、黄丝草和黑藻等沉水植物．其中菹草、黑藻的出现频率和概念生物量,分别在４、６、７、８和９月为最高;围栏内沉水植物的种类和生物量的变化与河蟹的放养密度关系密切,当河蟹的放养密度不超过３０只·ｈｍ~（－２）时,围栏内沉水植物的生物量与对照组均有明显的增加趋势,由此可证,女山湖大面积的围栏养蟹和适宜的放养密度,有效地利用和保护了围栏区内的沉水植物资源 相似文献
13.
放养前后鱼塘沉积物中氮、磷、有机质、色素的变化及环境意义 总被引：1，自引：0，他引：1
通过对针塘沉积物中营养盐,有机质及色素在放养前后的测试,对比分析了在人类活动（养殖）的影响下,由于鱼塘水体快速富营养化而引起底质上述指标的变化过程,其中快速沉积环境极有利于沉积色素的保存,具有较好的环境营养状况指示意义,同时有机质,色素和营养盐之间存在着密切的相关关系,这为利用色素方法研究短时间序列环境演变,尤其是在近代人类活动影响下的环境变化提供了一定的依据。 相似文献
14.
《Acta Geochimica》2017,(1)
Geosorbents are the main host of anthropogenic organic pollutants and play a vital role in their fate and transport in the natural environment.Soil and sediment are the most common and abundant geosorbents in the natural environment;their interactions with organic pollutants,especially sorption and desorption processes,have been extensively studied from the perspectives of thermodynamics and kinetics.Recently,the aging of organic pollutants in geosorbents has drawn increased attention,leading to an improved understanding of interactions between organic pollutants and geosorbents and informing remediation criteria.Aging has been deemed important in accurately assessing ecologic and health risks of organic pollutants,and both positive and negative impacts have been reported in studies of natural and artificial sorbents.This paper summarizes recent research progress on organic pollutant aging in geosorbents,including related mechanism research,influence factors,bioavailability assessments,and biological and physicochemical remediation of aged organic pollutants.We also discuss issues in the current research and bring forward suggestions for future study. 相似文献
15.
湖泊沉积物碳库作为湖泊生态系统的重要组成部分,对湖泊碳循环起重要作用,而蓝藻水华衰亡过程对湖泊碳库稳定性影响研究较少本研究采集太湖蓝藻、湖水、沉积物样品,建立蓝藻水沉积物室内模拟实验系统,分析蓝藻水华衰亡过程中沉积物碳库易氧化有机碳(EOC)、惰性有机碳(ROC)、微生物量碳(MBC)、轻组有机碳(LFOC)和重组有机碳(HFOC)的变化规律,探究蓝藻水华衰亡过程对湖泊碳库稳定性的影响结果表明,蓝藻水华衰亡前期(1～9天),ROC缓慢下降,EOC和LFOC快速下降,MBC有所增加;衰亡中期(10～45天),沉积物TOC和ROC含量升高;衰亡末期(46～63天),HFOC和ROC等稳定有机碳进入一个从缓慢分解逐渐趋于稳定的阶段周期性的蓝藻水华暴发、衰亡和湖泊稳定性有机碳的日渐累积,最终会对沉积物碳库有机碳组分及其稳定造成显著影响. 相似文献
16.
Reva Fabrikant 《Marine pollution bulletin》1984,15(7):249-253
Changes in the population density and size of the clam Parvilucina tenuisculpta were related to municipal waste effluent (in particular, organic nitrogen concentration) off the coast of Palos Verdes, California. Average clam size increased as sediment organic nitrogen concentration increased, but population density increased until organic nitrogen concentration reached a critical level when population density decreased dramatically. These effects were explained in terms of increased available nutrition (in the form of sediment organic nitrogen pollutants) enhancing both population and individual size growth. However, when a critical concentration of organic decomposition products was reached, population density decreased due to the toxicity of the released compounds. It is suggested that Parvilucina tenuisculpta would make a good bioindicator of organic enrichment pollution. 相似文献
17.
Abundance and biochemical composition of organic materials in sediments of the estuaries of Mundaka and Bilbao (SE Bay of Biscay) were analysed to assess the effect of organic wastes released to these systems. Organic and labile contents were higher in the sediments of Bilbao, denoting organic enrichment with poorly decomposed materials by human dumping. Spatially, organic matter distribution skewed seaward in Bilbao and upward in Mundaka, in agreement with the location of major point sources of sewage. Labile material, proteins and protein:carbohydrate ratio showed upward increases in both estuaries, attributed to the oxygen restrictive conditions to decompose organic materials. Vertical distribution of organic components into sediments reflected the history of human activities. In Bilbao, the significant reduction of organic and labile compounds, and the decrease of protein:carbohydrate values in top layers seem a result of recent remedial actions to reduce urban sewage inputs and improve environmental conditions. Higher contributions of proteins and lipids were associated with anthropogenic materials, and higher contributions of carbohydrates with autochthonous materials. High protein:carbohydrate values indicate poorly decomposed materials of human origin. The close relationship of carbohydrates with chloropigments in Mundaka suggests that phytobenthic populations and derived detritus contributed to a greater extent to the organic fraction in this estuary. 相似文献
18.
太湖表层沉积物中 OM,TN,TP 的现状与评价 总被引：43，自引：5，他引：43
根据1990年8月至1993年10月,对太湖进行的14次调查442个表层沉积物中OM、TN、TP进行分析,其结果表明,三者均有明显的平面分布特点。近年来OM和TN增加速度较快,TP相对较慢。引用有机指数和有机氮评价太湖表层沉积物,仍处于较清洁至尚清洁状态。但东太湖底泥已遭受较严重的有机物污染。 相似文献
19.