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1.
Textile wastewater contains huge quantities of nitrogen (N)‐containing azo‐dyes. Irrigation of crops with such wastewater adds toxic dyes into our healthy soils. One of the ways to prevent their entry to soils could be these waters after the dyes' biodegradation. Therefore, the present study was conducted to evaluate the impact of textile dyes on wheat growth, dye degradation efficiency of bacteria‐fungi consortium, and alleviation of dye toxicity in wheat by treatment with microbial consortium. Among dyes, Red‐S3B (3.19% N) was found to be the most toxic to germination and growth of seven‐day‐old wheat seedlings. Shewanella sp. NIAB‐BM15 and Aspergillus terreus NIAB‐FM10 were found to be efficient degraders of Red‐S3B. Their consortium completely decolorized 500 mg L?1 Red‐S3B within 4 h. Irrigation with Red‐S3B‐contaminated water after treatment with developed consortium increased root length, shoot length, root biomass, and shoot biomass of 30‐day‐old wheat seedlings by 47, 18, 6, and 25%, respectively, than untreated water. Moreover, irrigation after microbial treatment of dye‐contaminated water resulted in 20 and 51% increase in shoot N content and N uptake, respectively, than untreated water. Thus, co‐inoculation of bacteria and fungi could be a useful bioremediation strategy for the treatment of azo‐dye‐polluted water.  相似文献   

2.
为了解水深梯度对苦草克隆生长与觅食行为的影响,通过大型原位浮台实验,将苦草幼苗盆栽后悬挂在不同水深(1.0、2.5、4.0、5.5、7.0 m)下培养,比较其生物量、无性系分株数、出芽数、株高、最大根长和匍匐茎总长的变化,并且评估了植株生物量对这些性状的影响.研究结果表明,随水深的增加苦草的生物量、无性系分株数、出芽数、最大根长、匍匐茎总长均显著降低,而株高随水深梯度呈先增加后降低的趋势.植株生物量仅对出芽数没有显著影响.水深梯度与植株生物量的交互作用仅对无性系分株数和匍匐茎总长有显著影响,而对其他性状没有显著影响,说明这两个性状对水深的响应受到个体发育的影响.  相似文献   

3.
选择桂林会仙喀斯特湿地,以不同富营养化水体中生长时期为6月(生长旺盛期)和8月(暴发高峰期)的水葫芦(Eichhornia crassipes)为研究对象,探讨不同富营养化条件下水葫芦的生长及表型可塑性响应特征,以揭示水葫芦对不同富营养化水体的生态适应机制.结果表明:水葫芦的株高、根长和叶绿素含量均随水体富营养化程度的增加而降低,叶柄数、叶柄宽、叶片数、叶长、叶宽、匍匐茎数和分株速率随着水体富营养化程度的增加而升高;各性状参数在暴发高峰期均略高于生长旺盛期;根生物量、茎生物量、叶生物量和总生物量均随水体富营养化程度的加深而增加,茎生物量高于根生物量和叶生物量;水葫芦生物量的分配以及性状间的权衡关系(根生物量比、茎生物量比、叶生物量比和茎叶比等)因生长时期的不同而呈现差异性,表现出较强的表型可塑性特征;水体总有机碳、总氮、总磷、硝态氮、氨氮和叶绿素a浓度分别与水葫芦的茎生物量、叶宽、匍匐茎数和分株速率间存在显著的正相关关系,与根长、株高、叶生物量比和茎叶比间存在显著的负相关关系;水葫芦的表型可塑性指数在0.009~0.792之间,叶重比的可塑性指数最大,根冠比最小,重度富营养化水体下的可塑性指数最大.在会仙喀斯特湿地不同富营养化水体环境中,水葫芦通过外部形态结构调节和生物量的配比关系,产生了有利于其入侵和存活的较强的表型可塑性,是其生存繁殖的重要响应机制之一.  相似文献   

4.
Lemnaceae or duckweed is an aquatic plant that can be used to recover nutrients from wastewaters. The grown duckweed can be a good resource of proteins and starch, and utilized for the production of value‐added products such as animal feed and fuel ethanol. In the last eleven years we have been working on growing duckweed on anaerobically treated swine wastewater and utilizing the duckweed for fuel ethanol production. Duckweed strains that grew well on the swine wastewater were screened in laboratory and greenhouse experiments. The selected duckweed strains were then tested for nutrient recovery under laboratory and field conditions. The rates of nitrogen and phosphorus uptake by the duckweed growing in the laboratory and field systems were determined in the study. The mechanisms of nutrient uptake by the duckweed and the growth of duckweed in a nutrient‐limited environment have been studied. When there are nutrients (N and P) available in the wastewater, duckweed takes the nutrients from the wastewater to support its growth and to store the nutrients in its tissue. When the N and P are completely removed from the wastewater, duckweed can use its internally stored nutrients to keep its growth for a significant period of time. A modified Monod model has been developed to describe nitrogen transport in a duckweed‐covered pond for nutrient recovery from anaerobically treated swine wastewater. Nutrient reserve in the duckweed biomass has been found the key to the kinetics of duckweed growth. Utilization of duckweed for value‐added products has a good potential. Using duckweed to feed animals, poultry, and fish has been extensively studied with promising results. Duckweed is also an alternative starch source for fuel ethanol production. Spirodela polyrrhiza grown on anaerobically treated swine wastewater was found to have a starch content of 45.8% (dry weight). Enzymatic hydrolysis of the duckweed biomass with amylases yielded a hydrolysate with a reducing sugar content corresponding to 50.9% of the original dry duckweed biomass. Fermentation of the hydrolysate using yeast gave an ethanol yield of 25.8% of the original dry duckweed biomass. These results indicate that the duckweed biomass can produce significant quantities of starch that can be readily converted into ethanol.  相似文献   

5.
针对人工湿地冬季净化能力不足以及不同湿地植物种植方式可能影响其净化效果的湿地构建问题,通过小试实验,研究了沙基法和浮床法种植水芹(Oenanthe javanica(Bl.)DC.)对冬季人工湿地净化富营养水体效果的影响.在整个冬季,4个实验周期中,处理期间总磷(TP)和总氮(TN)去除率表现出显著差异:对照组(CK)、沙基种植组和浮床种植组4个周期对TP的去除率平均值为20.17%±19.23%、59.60%±7.54%和45.44%±29.22%;对TN的去除率平均值依次为:29.83%±19.65%、64.89%±23.01%和60.50%±25.86%.与CK组相比,冬季种植水芹可显著提高湿地对TP和TN的去除率;与浮床种植方式相比,沙基种植方式的TP和TN去除率略有提高.而对于COD的去除率,沙基种植组周期间波动较大(-27.5%~52.92%),浮床种植组组周期间更为平稳(10.83%~40.42%),浮床种植组在全部4个周期的平均去除率(23.13%±14.41%)略高于沙基种植组(19.38%±35.38%).2种种植方式下,水芹均可安全适应冬季温带气候;与沙基种植法相比,浮床种植方式更有利于植物总生物量的增加,特别是根系生物量的增加;相对于浮床种植,传统的沙基种植法能使水芹根系在温带冬季大部分时间内保持较高的活力和泌氧能力.因此,考虑到建设成本,在浅水区域可优选传统的沙基(或底泥)种植方式;在深水区域,使用浮床种植的方式,也能保证耐寒水生植物安全度过冬季和保持较高的净化能力.  相似文献   

6.
人工湿地植物研究   总被引:193,自引:10,他引:193  
本文阐述了植物在人工湿地污水净化过程中作用及存在的若干问题,提出了研究人工湿地植物的一些设想,植物在人工湿地中起着非常重要的作用,不但直接摄取利用污水中的营养物质、吸收富集污水中的重金属等有毒有害物质;而且输送氧气到根区,提供根区微生物生长、繁殖和降解对氧的需求;还能维持和加强人工湿地系统内的水力学传输,但目前人工湿地植物的应用还存在着枯死衰退、杂草丛生和根系扩展较浅等问题,影响人工湿地的净化功能,通过对人工湿地植物生理生态特性如气体代谢、光合作用、逆境生理和相生相克等研究,筛选出优良植物种类,创造适宜人工生,将有利于发育发挥湿地植物功能,提高人工湿地污水处理能力。  相似文献   

7.
为探究重污染底泥对沉水植物繁殖体萌发和幼苗生长影响,以苦草(Vallisneria natans)种子和黑藻(Hydrilla verticillata)冬芽为研究对象,以轻污染底泥为对照组,通过室内模拟实验研究了重污染底泥对两种繁殖体萌发和幼苗生长、生理特性的影响。实验结果表明,与轻污染底泥相比,重污染底泥对苦草种子萌发和幼苗生长无显著影响。黑藻冬芽萌发和幼苗地上部生物量在两组间没有显著差异,但重污染底泥组幼苗的地下部生物量显著高于轻污染底泥组,其地上部和地下部生物量比值由7.06±0.38下降至2.97±0.08。此外,苦草和黑藻幼苗受到重污染底泥胁迫表现出不同的生理响应。苦草幼苗叶片的类胡萝卜素含量显著减少,可溶性糖和蛋白含量分别降低11.56%、24.10%,根系活力也明显受到抑制,仅为(34.93±3.28) mg/(g·h);黑藻幼苗生理响应与苦草略有不同,其叶片的叶绿素a、b含量显著增加,根系活力降低44.29%,可溶性糖和蛋白含量在轻污染组和重污染组之间无显著差异。由此可见,重污染底泥对苦草种子和黑藻冬芽的萌发影响不显著,但会明显影响幼苗的生长发育和生理特性,研究结果为...  相似文献   

8.
为明确消落区土壤养分对植物生长的影响,通过室内栽培试验,研究三峡库区秭归消落区土壤3种氮磷水平下4种草本植物—鬼针草(Bidens pilosa)、苍耳(Xanthium sibiricum)、水蓼(Polygonum hydropiper)、藜(Chenopodium album)长势及氮、磷计量特征.结果表明,消落区土壤中生长的植物氮含量为7.98~19.4 mg/g,磷含量为0.740~3.880 mg/g,氮磷比为3.48~13.70,判别植物生长受氮限制.外源氮磷的添加促进植物氮、磷含量明显升高,但氮磷比没有明显变化;外源氮磷添加解除植物受氮的限制作用.4种植物对消落区土壤低氮环境具有一定的适应能力.比较消落区土壤中4种植物长势,鬼针草生物量、相对生长率、根茎生物量比最高,氮磷养分丰富对鬼针草生长促进作用最明显,表明鬼针草更易于在氮、磷贫乏的三峡库区消落区形成优势群落.  相似文献   

9.
钱奎梅  刘霞  陈宇炜 《湖泊科学》2021,33(1):102-110
着生藻类一般生长位置相对稳定,其群落分布主要受环境因素的影响,同时,着生藻类还是重要的水环境指示生物.本研究对鄱阳湖丰水期5个典型湖区(主航道、西部湿地、南矶湿地、撮箕湖和东南湖汊)着生藻类的群落结构特征进行调查,包括生物量、优势种及生物多样性,分析影响着生藻类群落区域分布的环境因子,以期为鄱阳湖水环境保护和水资源合理利用提供基础资料.结果表明:鄱阳湖着生藻类群落以硅藻、绿藻和蓝藻为主;鄱阳湖着生藻类总生物量有着明显的区域差异:主航道区域的生物量相对最高,平均为419 mg/m^2;其次是东南湖汊,平均为322 mg/m^2;南矶湿地和西部湿地分别为172和52 mg/m^2;而撮箕湖的总生物量相对最低,为9 mg/m^2.主航道的着生藻类优势种群为绿藻和硅藻,西部湿地、南矶湿地、撮箕湖和东南湖汊4个区域的优势种群为硅藻.冗余分析结果显示鄱阳湖丰水期着生藻类群落分布与总磷、电导率、pH值、总氮、硝态氮和悬浮物等理化因子关系较为密切.鄱阳湖主航道与长江连通,水体流速高;西部湿地、南矶湿地、撮箕湖和东南湖汊为季节性连通湖泊,丰水季节与主湖区水体连为一体,枯水季节独立蓄水.5个湖区的区域差异是导致其着生藻类群落结构差异的重要原因之一.着生藻类的多样性指数分析表明鄱阳湖水体处于中度污染状态.  相似文献   

10.
入湖河口湿地四种植物群落类型的土壤氮素空间分布特征   总被引:1,自引:0,他引:1  
任奎晓  陈开宁  黄蔚  施娴 《湖泊科学》2012,24(6):849-857
对江苏省溧阳市大溪水库的洙漕河河口湿地中香蒲、水蓼、灯心草和芦苇四种植物生物量、氮含量及植物群落的土壤氮素分布特征进行研究,结果表明:四种植物地上生物量、地上组织氮含量、地下生物量、地下组织氮含量存在显著差异;土壤烧失量(LOI)、总氮(TN)、硝态氮(NO3--N)在垂直分布上表现为由表层向下减少的总体分布趋势,铵态氮(NH4+-N)浓度的剖面变化呈现先减少后增加的趋势;四种植物群落土壤氮浓度各不同,但均大于对照,以有机氮为主,说明湿地具有一定的储氮能力;不同的植物群落影响湿地氮素的分布.相关性分析显示,土壤LOI与TN、NO3--N和NH4+-N均存在极显著相关性,无机氮构成比例较小,仅为1.41%,表明土壤中的氮素主要以有机氮的形式存在;土壤氮浓度与植物生物量及组织氮含量相关性不大,说明土壤氮形态浓度不仅受到植物生长的影响,同时也可能受到植物根区环境、微生物数量与活性等的影响.  相似文献   

11.
Rhizosphere microorganism is an important bio‐component for wastewater treatment in constructed wetlands (CWs). Microbial abundance and enzyme activities in the rhizospheres of nine plant species were investigated in an integrated vertical‐flow CW. The abundance of denitrifiers, as well as urease, acid, and alkaline phosphatase activities were positively correlated to plant root biomass. The abundance of bacteria, fungi, actinomycetes, ammonifiers, denitrifiers, and phosphorus decomposers, related to nutrient removal efficiencies in CWs, greatly varied among rhizospheres of different plant species (p < 0.05). Significant differences in rhizosphere enzyme activity among plant species were also observed (p < 0.05), with the exception of catalase activity. The principal component analysis using the data of microbial abundance and enzyme activity showed that Miscanthus floridulus, Acorus calamus, and Reineckia carnea were candidates to be used in CWs to effectively remove nitrogen and phosphorus from wastewater.  相似文献   

12.
Pistia stratiotes L. obtained from a eutrophic lake in Ibadan, Nigeria was examined for its mineral and trace element composition. The study indicated that the shoot system accumulated more potassium, calcium and magnesium, whereas the root system accumulated significantly more cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, nickel, sodium and zinc. The possible utilization of this aquatic plant for the treatment of polluted waters and industrial effluents is discussed.  相似文献   

13.
岑璐瑶  陈滢  张进  刘敏  吴庆明 《湖泊科学》2019,31(2):365-374
利用种植不同植物的人工湿地对污水厂尾水进行深度处理以达到更严格的排放标准.利用5块尺寸一致的中试规模人工湿地,以潮汐流作为运行方式,研究不同植物对尾水的处理效果.经过一年的实验,结果表明:5块人工湿地出水各指标均能达到提升标准的排放要求.在不同植物的去污效果对比实验中,种植芦苇(Phragmites communis)的人工湿地对化学需氧量(COD)、氨氮和总氮(TN)的平均去除率均为最高,分别为24.01%、68.15%和92.70%;种植风车草(Cyperus alternifolius)的人工湿地对TP的平均去除率最高,为71.68%.在不同季节的去污效果对比实验中,春季芦苇湿地对COD、氨氮和TN的去除效果最好,平均去除率分别为52.51%、76.06%和92.04%,美人蕉(Canna indica)湿地对TP去除效果最好,平均去除率为66.72%;夏季对COD、氨氮、TP和TN处理效果最好的分别是种植丝带草(Phalaris arundinacea)、菖蒲(Acorus calamus)、风车草和芦苇的人工湿地,平均去除率分别为15.83%、78.11%、67.30%和91.73%;秋季对COD、氨氮、TP、TN处理效果最好的分别是种植芦苇、丝带草、风车草、美人蕉的人工湿地,平均去除率分别为12.19%、58.82%、83.16%和94.01%;冬季对COD去除效果最好的是种植丝带草的人工湿地,平均去除率为33.39%,对氨氮、TP处理效果最好的是种植美人蕉的人工湿地,平均去除率分别为76.33%和79.43%,对TN处理效果最好的是种植芦苇的人工湿地,平均去除率为94.97%.在以后的实际工程中,可以考虑用种植不同季节、不同指标对应的最佳去污植物为主,并且搭配种植其他植物的人工湿地进行污水厂尾水的深度处理.  相似文献   

14.
Municipal wastewater (MWW) or urban wastewater (UWW) is generated by the domestic consumption of freshwater, which contains a huge amount of nutrients. The release of unprocessed wastewater causes eutrophication and harms aquatic life. Moreover, ingestion of polluted MWW causes a severe negative impact on human health. Microalgae are unicellular, eukaryotic photosynthetic organisms and have the capability of nutrient assimilation in the presence of light. Moreover, the produced biomass can be used for the generation of value-added bioproducts such as bioenergy. However, conventional microalgae-based MWW treatment is not as sustainable on a commercial scale. Therefore, more advanced approaches using microalgae need to be integrated in wastewater cultivation systems to improve nutrient removal efficiency. Thus, the present review explores the use of microalgae for the removal of nutrients from MWW, provides an outlook of direct and indirect methods of nutrient uptake from wastewater and the effects of the influencing factors in biomass growth. Moreover, the review also gives insight into recent approaches used for MWW treatment and the applications of algal biomass resulting from treated wastewater. It is predicted that microalgae-based MWW treatment systems will be a significant green approach to help eliminate nutrient loads and implement circular economy.  相似文献   

15.
人工湿地废水处理系统的生物学基础研究进展   总被引:45,自引:3,他引:45  
成水平 《湖泊科学》1996,8(3):268-273
主要阐述了人工湿地废水处理系统中生物学基础的研究进展,至今,对作为湿地生产者的水生植物研究较多,水生植物除直接吸收利用废水中的营养物质,吸附和富集重金属外,还起输送氧气至根区,形成根区多种微环境和维护湿地水力传输的作用;而对作为湿地分解者的微生物的研究较少,湿地微生物的代谢活动是废水中有机物质降解的基础机制。  相似文献   

16.
人工湿地植物根区微生物与净化效果的季节变化   总被引:42,自引:1,他引:42  
人工湿地污水处理系统具有净化效果显著、建设和运行费用低廉、管理简便等优点.近年来越来越受到人们的重视.人工湿地生态系统受环境影响较大,研究人工湿地在不同季节的净化功能对于充分发挥其作用具有重要意义.对不同季节的芦苇(Phragmite saus-tralis)、茭白(Zizania caduciflora)和香蒲(Typha latifolia)等湿地系统植物根区、无植物对照基质微生物分布状况以及净化效果进行了研究,结果显示:(1)种植不同植物的湿地系统根区微生物数量不同,其湿地净化效果也不同;(2)季节变化显示湿地系统秋季的细菌总数量比夏季高;但对照系统夏季的真菌和放线菌数量明显高于秋季;(3)湿地系统总磷(TP)的去除率夏季高于秋季;(4)相关性分析发现湿地植物根区的细菌总数与BOD5的去除率之间存在显著相关性;而根区微生物数量与TP、CODCr和凯氏氮(KN)的去除率之间不存在显著相关性,具体机理还需进一步研究.  相似文献   

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18.
A simple field‐based method for directly parameterizing root water uptake models is proposed. Stem psychrometers and sap flow meters are used to measure stem water potential and plant transpiration rate continuously and simultaneously. Predawn stem water potential is selected as a surrogate for root zone soil water potential to examine and parameterize the root water uptake–water stress response functions. The method is applied to two drooping sheoak (Allocasuarina verticillata) trees for a period of 80 days, covering both a dry season and a wet season. The results indicate that the S‐shape function is more appropriate than the Feddes piecewise linear function for drooping sheoak to represent the effect of soil moisture stress on its root water uptake performance. Besides, the water stress function is found to be not only a function of soil moisture but also dependent of the atmospheric demand. As a result, the water stress function is corrected for the effect of atmospheric conditions. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

19.
This paper characterizes a seasonally inundated Danish floodplain wetland in a state close to naturalness and includes an analysis of the major controls on the wetland water and nitrogen balances. The main inputs of water are precipitation and percolation during ponding and unsaturated conditions. Lateral saturated subsurface flow is low. The studied floodplain owes its wetland status to the hydraulic properties of its sediments: the low hydraulic conductivity of a silt–clay deposit on top of the floodplain maintains ponded water during winter, and parts of autumn and spring. A capillary fringe extends to the soil surface, and capillary rise from groundwater during summer maintains near‐saturated conditions in the root zone, and allows a permanently very high evapotranspiration rate. The average for the growing season of 1999 is 3·6 mm day?1 and peak rate is 5·6 mm day?1. In summer, the evapotranspiration is to a large degree supplied by subsurface storage in a confined peat layer underlying the silt–clay. The floodplain sediments are in a very reduced state as indicated by low sulphate concentrations. All nitrate transported into the wetland is thus denitrified. However, owing to modest water exchange with surrounding groundwater and surface water, denitrification is low; 71 kg NO3–N ha?1 during the study period of 1999. Reduction of nitrate diffusing into the sediments during water ponding accounts for 75% of nitrate removal. Biomass production and nitrogen uptake in above‐ground vegetation is high—8·56 t dry matter ha?1 year?1 and 103 kg N ha?1 year?1. Subsurface ammonium concentrations are high, and convective upward transport into the root zone driven by evapotranspiration amounted to 12·8 kg N ha?1year?1. The floodplain wetland sediments have a high nitrogen content, and conditions are very favourable for mineralization. Mineralization thus constitutes 72% of above‐ground plant uptake. The study demonstrates the necessity of identifying controlling factors, and to combine surface flow with vadose and groundwater flow processes in order to fully comprehend the flow and nitrogen dynamics of this type of wetland. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

20.
湿地植被地上生物量是衡量湿地生态系统健康状况的重要指标,对于珍稀水禽越冬繁殖、全球碳循环、生态净化具有重要意义,是生态学与遥感解译的研究热点之一.针对于地上生物量的测算,卫星遥感数据覆盖范围广但其空间分辨率较低,无人机遥感数据空间分辨率高但采集范围小,同时受湿地面积、观测系统及外界环境等条件的影响,使得遥感影像地上生物量反演更加复杂和困难.本研究基于无人机和高分一号数据对升金湖草滩植被地上生物量反演进行研究,结合升金湖保护区4个样区无人机可见光影像与相应样区实测样本数据,建立地上生物量与可见光波段、多种可见光植被指数的线性、幂函数、多项式、对数回归模型,并通过可决系数(R2)、平均绝对误差(MAE)和均方根误差(RMSE)对模型进行精度评价,选择最优模型对无人机影像进行地上生物量反演;通过可见光波段反演得到的生物量,与高分一号WFV归一化差分植被指数(Normalized Difference Vegetation Index,NDVI)影像相结合进行回归建模,获取整个升金湖草滩植被地上生物量分布.结果表明,利用无人机红光波段建立的多项式方程对地上生物量反演有着最高模拟精度,R2=0.86、预测精度MAE=111.33 g/m2RMSE=145.42 g/m2,且红光波段生物量反演方法得到的结果与实际生物量分布一致性较高,高分一号WFV NDVI与无人机反演生物量构建的多项式模型为最优模型,R2为0.91.本研究利用无人机和高分一号数据进行生物量反演研究,整合多源遥感数据优点,以获取更加丰富和准确的信息,进而提高地上生物量反演精度,为湿地监测和湿地恢复管理提供数据和技术支撑,具有重要研究意义和应用价值.  相似文献   

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