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1.
工业搬迁区绿化带土壤铜污染及其在植物体内的迁移   总被引:1,自引:0,他引:1  
老工业搬迁区主要道路两旁绿化带土壤由于历经老工业企业的变迁和环境的污染破坏,可在一定程度上对这一地区环境的历史变迁及重金属污染状况起到指示作用。采集沈阳铁西老工业搬迁区绿化带土壤及其绿化乔木和灌木植株样品,分析土壤中铜的总量及生物有效态含量,同时分别分析了绿化乔木(8种)和绿化灌木(6种)植株根、枝条和叶片的含铜量。结果表明,搬迁区绿化带土壤中含铜量为29.14~166.95mg/kg,显著高于沈阳市土壤铜元素的背景值;土壤有效态铜为0.23~1.72mg/kg,达到中等水平(0.3~1.0mg/kg)的占采样点总数的70.0%。数据还显示,绿化乔木和灌木对铜的蓄积能力依品种不同差异显著,同种植物不同部位(根、枝条和叶片)对铜的富集能力不同;总体上,绿化乔木植株体内含铜量的分布规律为根叶片枝条或叶片根枝条,绿化灌木植株体内含铜量的分布规律为根叶片枝条。对铜蓄积能力较强的绿化乔木为榆叶梅(Amygdalus triloba Lindl.)、垂柳(Salix babylonica Linn.)、旱柳(Salix matsudana Koidz.)和银杏(Ginkgo biloba),对铜蓄积能力较强的绿化灌木为大叶女贞(Ligustrum lucidum Ait.)、小叶女贞(Ligustrum quihoui Carr.)和紫叶小檗(Berberis thunbergii cv.Atropurpurea)。  相似文献   

2.
在三垟湿地河道内选取富营养化程度不同的两个区域,进行为期6个月(2016年5—10月)的围隔(a和b)种植菱角修复富营养化水体试验研究,每月对围隔内外的水质指标、浮游生物等进行监测。结果发现:(1)菱角的种植对水体透明度、营养盐和叶绿素a浓度等指标均有明显改善作用。(2)围隔内外水体透明度在7月差异最显著,围隔a、b内透明度比围隔外分别增加20、63cm,分别提高0.4、2.3倍。(3)TN在5月差异最显著,围隔a、b内TN较围隔外分别下降39.7%(质量分数,下同)、20.6%。(4)围隔a内外的TP在6月差异最显著,围隔b则在5月差异最显著,分别较围隔外下降58.6%、42.6%。(5)氨氮在6月差异最显著,围隔a、b内分别较围隔外下降72.1%、61.3%。(6)围隔a内外的叶绿素a在7月差异最显著,围隔b则在5月差异最显著,分别较围隔外下降61.4%、77.5%。(7)围隔内高锰酸盐指数均低于围隔外。(8)围隔内外的浮游生物优势种不同,围隔内浮游动物密度显著降低,但围隔内外浮游生物多样性指数差异不显著。  相似文献   

3.
以金鱼藻为研究对象,分析悬浮物不同扰动方式(机械扰动和曝气扰动)、扰动强度以及悬浮物浓度对沉水植物生理特性的影响。结果表明,与曝气扰动相比,机械扰动对金鱼藻生理特性影响显著,搅拌强度的增大,金鱼藻叶绿素a、叶绿素b、类胡萝卜素含量和POD活性不断下降,60 r/min时下降最快,搅拌强度与POD活性显著负相关。曝气扰动在前期促进金鱼藻的生长,后期抑制其生长,曝气强度4 m3/h时,金鱼藻生理指标降低最大,曝气强度与金鱼藻生理特性相关性不显著。随悬浮物浓度升高,金鱼藻叶绿素a、叶绿素b、类胡萝卜素含量先升高后下降,金鱼藻生长最适悬浮物浓度为0.4~0.8 g/L。  相似文献   

4.
外源铜胁迫对木本蔬菜生长及品质的影响研究   总被引:1,自引:0,他引:1  
采用盆栽技术,研究了木本蔬菜香椿对不同质量浓度(0、100、200、400、800mg/kg)Cu2+胁迫的响应。结果表明,低质量浓度(≤200mg/kg,下同)的Cu2+胁迫可促进香椿的生长,在高质量浓度(≥200mg/kg,下同)Cu2+胁迫下香椿的芽长、冠幅、株高增长受到抑制;随着Cu2+胁迫浓度的升高,香椿叶片中的叶绿素a、叶绿素b含量先升高后降低,丙二醛(MDA)含量先降低后升高,可溶性蛋白含量先降低后升高而后又降低,可溶性糖含量先降低后升高;随着Cu2+胁迫浓度的升高,综合香椿体内的叶绿素、MDA、可溶性蛋白、可溶性糖、有机酸、维生素C含量变化结果可知,香椿对低浓度的Cu2+胁迫具有一定的抗逆性,但是高浓度的Cu2+胁迫会对香椿的生长及叶片品质产生负面影响。  相似文献   

5.
为研究陕北黄土区土壤石油污染物对玉米种子出苗率和幼苗生长的影响,采用盆栽试验的方法,设置土壤不同石油浓度处理组,培养玉米2个月,测定了各处理组玉米的出苗率、株高、茎宽、生物量和叶片叶绿素浓度.结果表明:(1)土壤石油质量浓度即使为30 g/kg时,各处理组出苗率最终均为100%;土壤石油质量浓度达到20 g/kg及以上时,在一定程度上会推迟玉米种子的出苗时间.(2)土壤石油质量浓度达到1 g/kg就会对玉米茎的生长产生抑制作用,可以显著降低玉米株高,但对玉米茎宽影响不显著.随着土壤石油浓度的升高,对玉米株高的抑制作用显著增加.玉米茎宽总体上是随着土壤石油浓度的升高而减小,但土壤石油质量浓度为0~1g/kg或20~30 g/kg时,玉米茎宽没有显著差异.(3)当土壤石油质量浓度达到5 g/kg以上时,植株干质量随石油浓度升高而减少.土壤石油质量浓度达到20 g/kg时,会显著降低玉米根的含水率;达到30 g/kg时,会显著降低茎和叶的含水率.(4)土壤石油质量浓度为1、5 g/kg时,叶绿素a和叶绿素b浓度与土壤石油质量浓度为0 g/kg时没有显著差异;土壤石油质量浓度为10、20、30 g/kg时,叶绿素a和叶绿素b浓度显著低于土壤石油质量浓度为0 g/kg时,并且随土壤石油浓度的升高呈降低趋势.  相似文献   

6.
采用室内盆栽试验研究了灭菌与非灭菌两种土壤条件下Cr(Ⅲ)污染对苗期黑麦草的发芽率、生长发育、叶绿素、超氧化物歧化酶(SOD)活性及Cr积累的影响.结果表明,灭菌状态的发芽率、发芽数(GI)及活力指数(VI)均大于非灭菌状态;低浓度Cr(Ⅲ)对各生长指标有明显的促进作用,灭菌状态各生长指标(除根长外)明显高于非灭菌状态,Cr(Ⅲ)达200mg/kg时,两种状态下多数指标达最大值;植株外伤表明土壤经过灭菌提高了Cr(Ⅲ)对黑麦草伤害的抵抗上限;灭菌状态黑麦草对Cr的吸收远小于非灭菌状态,解释了叶绿素a、 b含量灭菌状态高于非灭菌状态、SOD活性非灭菌状态高于灭菌状态的原因,说明了土壤灭菌抑制Cr的吸收.  相似文献   

7.
康定柳对铯胁迫的生理生化响应及富集能力   总被引:2,自引:0,他引:2  
朱靖  陈珂  张渊  杨叶 《环境工程学报》2016,10(3):1515-1520
主要探讨康定柳(Salix paraplesia)在水培条件下对铯胁迫(133Cs+浓度0、50和200 μmol/L)的生理生化响应和富集修复能力。研究结果表明:铯胁迫造成了植物的过氧化损伤,且与胁迫浓度呈正相关;植物通过提高渗透调节能力(Pro)和抗氧化能力(SOD、POD和CAT)应对铯胁迫,但高浓度铯胁迫却显著抑制了植株抗氧化系统的作用。从植物光合荧光指标和叶绿素含量来看,低浓度铯能促进植物叶绿素合成且对光合能力影响不大,而高浓度铯胁迫则抑制了植物叶绿素的合成及光合能力。此外,与对照相比,低浓度铯胁迫能够显著促进植株的茎长,而高浓度铯胁迫则显著抑制了植株的生物量、根长和茎长,对植株生长发育的抑制作用明显。康定柳对水体中铯的富集量和富集系数均表现为根> 茎> 叶,铯主要富集在植株根部,且在高处理浓度下,植株富集量最高达到2.2358 mg/g DW。表明康定柳对水体中铯的污染具有较好的耐受性和修复潜力。  相似文献   

8.
长春南湖营养盐与叶绿素a的分布与富营养化评价   总被引:1,自引:0,他引:1  
在研究长春南湖水体中TP、TN和叶绿素a的时空分布及相关性的基础上,采用综合富营养化指数法对南湖水体进行评价。结果表明:(1)常温期,TP、TN和叶绿素a含量均为9月5月;9月的TP、TN为表层底层,叶绿素a含量为底层表层;5月的TP、TN和叶绿素a的含量均为底层表层;TP为渔场保护区人为活动区荷花池区,TN和叶绿素a含量均为渔场保护区荷花池区人为活动区。(2)冰封期,TP、TN和叶绿素a含量为水层冰层;TP、叶绿素a含量为渔场保护区人为活动区,TN为人为活动区渔场保护区。与常温期相比,TP、TN和叶绿素a含量总体上均为9月5月2月;各区水体中TP和叶绿素a含量的分布与常温期保持一致,而TN的分布有一定的变化。(3)相对于氮,磷含量的高低是控制藻类及浮游生物生长更为关键的因子。(4)9月的营养级别是中度富营养,2月的营养级别是中营养,5月的营养级别是轻度富营养。综合营养状态指数大小依次为9月5月2月。常温期不同功能区的营养级别均属轻度富营养。  相似文献   

9.
采用共生培养的实验方法,通过追踪测定宽叶香蒲(Typha latifolia)叶片中叶绿素含量、净光合速率、光呼吸速率及乙醇酸氧化酶(GO)、谷氨酰胺合成酶(GS)及过氧化氢酶(CAT)的活性,研究不同初始密度铜绿微囊藻(Microcystis aeruginosa)对宽叶香蒲叶片光呼吸特性的影响。结果表明,铜绿微囊藻初始密度为1.0×104ind/m L时,宽叶香蒲叶片叶绿素含量、净光合速率、光呼吸速率及GO、GS及CAT的活性增加,说明低密度铜绿微囊藻对宽叶香蒲叶片的光合作用及光呼吸具有促进作用;铜绿微囊藻初始密度为1.0×107ind/m L时,宽叶香蒲叶片净光合速率、光呼吸速率及GO、GS及CAT的活性呈现先增加后降低的趋势,表明经过一段时间培养后,高密度铜绿微囊藻对宽叶香蒲叶片的光合作用和光呼吸呈现出抑制作用。但是在净光合速率急剧降低的时候,光呼吸速率在短时间内仍然维持在一个较高水平,说明宽叶香蒲可能通过维持或增强光呼吸在一定程度上抵抗逆境胁迫。  相似文献   

10.
通过盆栽实验研究了典型磺胺类抗生素磺胺甲恶唑(SMZ)、磺胺甲基嘧啶(SM1)和磺胺噻唑(ST)对油菜叶片内抗氧化酶(POD)活性、叶绿素(CHL)含量和可溶性蛋白(SP)含量的影响。结果表明:在低浓度染毒处理(15.0mg/kg)和高浓度染毒处理(45.0mg/kg)下,SM1、ST对油菜叶片中的CHL含量均有显著抑制作用(P0.05),SMZ对油菜叶片中的CHL含量有极显著抑制作用(P0.01)。3种磺胺类抗生素对油菜叶片SP含量的抑制作用随着染毒浓度的增加逐渐增强,其中SMZ对SP含量的抑制作用最大。两种浓度的染毒处理下,3种磺胺类抗生素对油菜叶片的POD活性均产生极显著诱导(P0.01)作用,并且SMZ对POD活性的诱导作用最为显著。综上,SMZ、SM1和ST均显著影响了油菜体内的生化过程,并且3种抗生素中SMZ的毒性效应最强。  相似文献   

11.
A number of key projects in the Environmental Protection Agency (EPA) particulate R&;D program having applicability to industry are presented. For electrostatic precipitators (ESP) there is presented the result of work on large diameter discharge electrodes which provide a decrease in penetration of up to a factor of 4 when compared to conventional small diameter electrodes. Also discussed is the multistage ESP which provides a collection efficiency that would require a collecting plate area 4 or 5 times larger with conventional ESP technology. The E-SOX technology makes use of the multistage concept to free up space in the ESP for SO2 removals of up to 90%. Electrostatically augmented fabric filtration provides a reduction in pressure drop of about 5 0% as compared to conventional fabric filtration. Wind tunnel modeling of windbreaks for material storage piles indicates a potential for providing engineering design data that would allow significant emission reduction caused by wind erosion  相似文献   

12.
This paper investigates some of the reflectivity characteristics that clouds (when modelled as solid bodies) must exhibit to be compatible with observations that the reflecting surface of a cloud (i) appears almost equally bright across its face, (ii) is brightest when the cloud is opposite to the Sun but decreases in brightness as the cloud moves to other positions and (iii) increases in brightness with increasing optical thickness of the cloud in the observer's line of sight. These observations, respectively, are shown to imply that the peak value of the bidirectional total reflectivity from a cloud surface (i) increases in inverse proportion to the cosine of the angle between the Sun and the normal to the cloud surface, as the incident angle increases, (ii) appears to be directed back in the direction of the incident radiation, and (iii) increases as optical thickness of the cloud in the observer's line of sight increases. The results could have application in many fields (e.g. modelling diffuse radiance distributions for cloudy skies).  相似文献   

13.
14.
张仁泉 《污染防治技术》2005,18(2):15-17,34
在实施ISO/IEC17025:1999标准《检测和校准实验室能力的通用要求》过程中,通过实验室质量管理体系内部审核的实践与系统分析,识别出内部审核实施阶段的关键环节,提出召开首次会议、收集审核证据、确定审核发现和召开末次会议的技术方法,对提高内部审核的质量和有效性、获得可靠的审核结论具有重要意义。  相似文献   

15.
Abstract

A computer model was used to take random samples from primary sample populations obtained from field trials to simulate the uncertainty of sampling for residue analysis of plant commodities and soil. The results indicate about 40%, 30% and 20% relative uncertainty when random samples of size 5, 10 and 25 are taken respectively, from a single lot. Therefore the sample size should be the same for establishing and enforcing legal limits.  相似文献   

16.
结合扬中生态环境的基本情况和存在的不足,进行了具体分析,对扬中未来生态建设的发展方向提出了建议及实施措施。  相似文献   

17.
The most common technique used for numerical simulations of tracer mixing is that of the numerical solution of the advection–diffusion equation with the unresolved fluxes parameterized using the similarity theory. Despite correct predictions of the overall directions of transport, models based on a numerical solution of the advection–diffusion equation lack sufficient accuracy to correctly reproduce the coupling of mixing with small scale processes which are sensitive to the microstructure of the tracer distribution. The objective of this paper is to revisit the basic formalism employed in numerical models used to investigate atmospheric tracers. The main mathematical method proposed here is the theory of kinematics of mixing which could be applied effectively for simulations of atmospheric transport processes. At the beginning of the paper, we introduce simple mathematical transformations in order to demonstrate how complex topological structures are created by mixing processes. These idealistic flow systems are essential to explain transport properties of much more complex three-dimensional geophysical flows. An example of the application of the kinematics of mixing to the analysis of tracer transport on a planetary scale is presented in the following sections. The complex filamentary structures simulated in the numerical experiment are evaluated using some commonly applied statistical measures in order to compare the results with the data published in the literature. The results of the experiment are also analysed with the help of simple conceptual models of fluid filaments. The microstructure of the tracer distribution introduced in the paper is essential to increase our understanding of atmospheric transport and to develop more realistic parameterizations of small-scale mixing. The presented results could also be used to improve calculations of the coupling between microphysical processes and tracer mixing.  相似文献   

18.
介绍了电解法生产次氯酸钠的原理 ,并在原有生产工艺的基础上进行了重新设计和对设备的重新选择、改造 ,得出了各个工艺参数的最佳值 ,生产出高品质的次氯酸钠  相似文献   

19.

Objective

This work aims to investigate the correlation between the photocatalytic activity determined by methylene blue bleaching (DIN 52980), stearic acid degradation, and degradation of acetone in gas phase.

Method

The photocatalytic TiO2 coatings included in this investigation ranged from thin commercially available coatings (ActivTM and BioCleanTM) and ready to use suspensions (Nano-X PK1245) to lab-produced PVD and sol?Cgel coatings. XRD analysis of the photocatalytic coatings showed that all the coatings consisted of nanocrystalline anatase, although the thickness and porosity varied considerably.

Results

The study showed that the reproducibility of the activity measurements was good. However, more importantly, the investigation showed that there is a good correlation between the activities determined by the different methods even though the characteristics of the photocatalytic coatings and the organic probe molecules varied considerably.

Conclusion

The overall findings of this work suggest that there is a good correlation between the investigated methods. These results are promising for the future work concerning standardization of methods for determination of the activity of photocatalytic films.  相似文献   

20.
Bhattacharya A  Sarkar SK 《Ambio》2003,32(1):70-75
India has a very extensive coastline of about 7515 km, rich in diverse living resources. These resources continue to deteriorate with rampant harvesting or are altered for other uses such as aquaculture and fisheries. The present paper deals with degrading coastal habitats in northeastern India, and projects the intensity of the stress arising from the collection of tiger prawn seeds (Penaeus monodon) for aquacultural farms and molluskan shells for poultry feed and edible lime. Indiscriminate exploitation of these resources leads to a heavy reduction of the species concerned and other associated marine communities. The magnitude of such destruction has been quantified. The impacts of biodiversity loss and their after-effects on the ecobalance of this coastal system have become a matter of great concern to ecologists to maintain security and sustainability. The authors propose a public awareness program on themes relating to the importance of biodiversity for human livelihoods.  相似文献   

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