共查询到20条相似文献，搜索用时 15 毫秒
1.
J. M. Hathaway R. S. Tucker J. M. Spooner W. F. Hunt 《Water, air, and soil pollution》2012,223(9):5903-5915
Nonpoint stormwater runoff remains a major threat to surface water quality in the USA. More effective stormwater control measures can be designed by understanding patterns in pollutant export with respect to the runoff hydrograph. In particular, nutrient concentrations in urban stormwater can cause deleterious effects in sensitive watersheds in the Southeast and Mid-Atlantic USA. A year-long study captured stormwater samples from 36 storm events at two catchments (one primarily impermeable and the other substantially wooded) and analyzed for total suspended solids and various nutrient species. Using these data, the first flush effect (the assumption that the initial portion of a rainfall-runoff event is more polluted than the later portions) was evaluated based on several published methods and definitions. Based on an analysis of multiple methodologies, the ranking of first flush strength among the pollutants was total suspended solids (TSS) > ammonia (NH3) > total Kjeldahl nitrogen > NO2-NO3 > total phosphorus > orthophosphate (O-PO4). Nitrogen species generally displayed a stronger first flush than phosphorus species, with O-PO4 showing the weakest first flush effect. Various relationships ° climate, land use, and the first flush strength were also explored. Of the rainfall characteristics analyzed, total rainfall and runoff volume each inversely affected the first flush strength of TSS on the more impervious catchment. Although orthophosphate did not have a strong first flush effect, the relative first flush strength for O-PO4 increased with increasing rainfall or runoff. Land use did not influence the first flush strength of the pollutants. On average, most pollutants exhibited a slight first flush effect, but substantial pollutant loading still occurred in the latter portion of the storm??s total runoff volume. Thus, treating the majority of a storm??s total pollutant load requires capturing a commensurate fraction of runoff volume. 相似文献
2.
河岸带植被对非点源氮、磷以及悬浮颗粒物的截留效应 总被引：1，自引：0，他引：1
选取草地河岸带和人工林地河岸带,开展了人工模拟农田施肥和径流污染物截留效果的现场试验。分别采集地表径流和渗透水水样,测定分析了总磷(TP)、总氮(TN)、氨氮(NH4—N)以及固体颗粒物的浓度。结果表明,草地河岸带对地表径流TP的截留效果显著优于林地河岸带,草地和林地河岸带对氮元素的截留效果趋于一致;河岸带对地表径流和渗透水中TN,TP和NH4—N的截留率是相似的;草地河岸带对固体颗粒物的截留效果优于林地河岸带;河岸带越宽,其截污功能越强;人为干扰造成了人工林地河岸带截污能力的减弱。并提出了河岸带管理的相关建议。 相似文献
3.
缓冲带截除农业面源强污染的效果 总被引：4，自引：2，他引：2
为了摸清草皮缓冲带对农田径流冲击负荷的耐受能力,通过工程尺度的现场试验,研究了高浓度污染负荷冲击对百慕大草皮缓冲带截除农业面源污染物能力的影响。结果表明:在高浓度污染负荷下,百慕大缓冲带能有效地截留农田径流中的悬浮固体(suspended solids,SS),SS浓度变化趋势与一般浓度污染负荷基本一致,前端下降速度较快,后端逐渐趋缓,2种污染负荷条件下末端出水SS质量浓度均在90mg/L以下,高浓度污染负荷冲击对农田径流SS的去除基本没有影响。缓冲带对高浓度氮磷污染负荷具有一定的净化效果,径流途径总氮(total nitrogen,TN)、氨态氮(ammonia nitrogen,NH4+-N)、总磷(total phosphorus,TP)的末端去除率为23%、16%和26%,分别为一般浓度污染负荷下末端去除率的59%、55%和70%;百慕大草皮缓冲带对渗流途径TN、TP具有一定的净化效果,2种浓度污染负荷下渗流水TN、TP浓度变化趋势基本一致,两者无显著差异(p>0.05),但TP去除速率较TN慢。该文为滨岸缓冲带的优化设计、维护管理及推广应用提供了依据。 相似文献
4.
M. Akram Hossain Mahbub Alam David R. Yonge Prashanta Dutta 《Water, air, and soil pollution》2005,164(1-4):79-89
Wet detention ponds are a preferable alternative in treating stormwater runoff. Literature suggests that a detention pond’s efficiency in removing principal pollutants of concern, TSS and metals, is highly variable and is affected by a complex array of factors including its geographic location. The objective of this paper was to investigate the TSS and metal removal efficiency of a highway stormwater detention pond in Spokane, Washington along with its flow regime. Pond influent and effluent data for TSS and metal were collected for approximately two years. TSS removal by the pond was found to be 68.1–99.4% with an average of 83.9%. Average metal removal efficiency was 54.7–64.6% which is 72.5–86.9% of the TSS removal. The pond’s flow regime was found to vary with its changing surface topography, a result of sedimentation of suspended solids. 相似文献
5.
太湖流域典型蔬菜地地表径流氮磷流失 总被引：11，自引：2，他引：9
以太湖流域典型蔬菜地为研究对象,采用田间径流池法进行田间小区试验,研究不同施肥模式下蔬菜地地表径流氮磷流失特征。结果表明：地表径流总氮流失量为45.76～60.45 kg/hm^2,总磷流失量为2.67～3.95 kg/hm^2。与常规施肥相比,优化施肥可使地表径流氮磷流失量分别减少2.48,0.31 kg/hm^2;而增氮施肥和增磷施肥处理的地表径流总氮流失量分别增加了7.76%,3.83%,总磷流失量增加2.84%,9.55%。总氮、总磷流失量与径流量呈显著线性相关,且总磷流失量与径流量的相关性更强（R2=0.913）。应加强汛期时段的田间管理和对磷的监控,减少磷流失量。有机肥与化肥以1：1配施,可有效降低菜地氮磷排放,提高蔬菜产量和氮肥利用率分别为25%,23%。 相似文献
6.
Reimer Herrmann 《Water, air, and soil pollution》1981,16(4):445-467
The PAH-pollutant loads resulting from storm runoff to a receiving stream are associated with high concentrations of suspended sediments. This is explained by the sorption coefficients and isotherms on street dust, suspended solids, bedload and other sorbents. Pollutographs for a stream with storm runoff mainly from storm water overflows from a combined sewered medium sized town show strong ‘first-flush’ phenomena. Rainfall and bedload contribute only to a lesser extent to the overall transport which stems from street dust washoff. High correlation between total PAH load and maximum flow, but no relation between total PAH load and the number of days since the previous storm, indicates a ‘low washoff case’ under ‘transport limited’ conditions. 3.4-Benzopyrene load was modeled by a pollutant washoff function analoguous to that of the EPA storm water model. 相似文献
7.
为了改善高位池对虾养殖水质,降低养殖环境污染,提高产品质量安全,对自主研发的高位池循环水养殖系统调控对虾养殖水质的效果进行研究,设计了3个不同循环量（20m·3h-1,T1）、（40m3·h-1,T2）、（60m3·h-1,T3）水处理系统进行高位池试验。结果表明,不同处理量的循环水系统均能有效地降低水体中NH4＋和NO2-,T1、T2、T3对NH4＋的相对消除率分别为46%、56%、57%;对NO2-的相对消除率分别为38%、34%、54%;各处理组对NO3-均没有明显的消除作用。T1、T2对PO34-无消除效果,T3对PO34-的相对消除率为36%。T1对COD无消除效果,T2、T3对COD的相对消除率为9%、15%。综合比较可知,60m·3h-1循环水处理系统对改善水质效果最好,40m3·h-1次之,20m3·h-1最差。 相似文献
8.
生物滴滤池是农村生活污水处理的主要技术之一,但其存在氮、磷去除能力有限,稳定性不高等缺点。为提高新型分层生物滴滤池的氮磷去除效率,探索最佳工艺条件,本文采用新型分层生物滴滤池为试验装置,考察了滤料种类、水力负荷、回流比等对装置去除污水中氮磷性能的影响。结果表明,当滤料为炉渣、水力负荷为4 m3·m-2·d-1、回流比为2∶1时滤池去除氮磷的效果最好,对NH4+-N、TN、TP、COD的平均去除率分别可达到87.08%、57.37%、66.04%、80.78%;采用较高的回流比是滴滤池提高脱氮效果的一条有效途径。 相似文献
9.
习惯施肥对菜地氮磷径流流失的影响 总被引：6，自引：0，他引：6
对菜地进行连续3年的定位监测试验。结果表明:与不施肥对照相比,菜农习惯施肥处理显著提高降雨径流中的总氮(TN)和硝态氮(NO3--N)流失质量浓度及流失量,3年监测期内总氮(TN)径流流失负荷为321kg/hm2,总磷(TP)流失负荷为134kg/hm2,分别占氮、磷养分投入总量的13.6%和13.2%,氮肥的流失系数约为5.6%。菜地氮素流失以硝态氮(NO3--N)形式为主,磷素流失以颗粒态磷(PP)形式为主。菜地氮、磷养分径流流失与径流量呈显著线性关系,菜地每流失1kg的总磷(TP),可溶性总磷(TDP)、总氮(TN)、硝态氮(NO3--N)、铵态氮(NH4+-N)所需要的径流量分别为77.5,322,52.5,67.5,404m3。 相似文献
10.
The removal and fate of runoff-derived heavy metals in a 1-yr old detention pond system were investigated during climatic conditions typical of the U.S. maritime Northwest. The catchment was a medium-sized, suburban parking lot near Portland, Oregon. Water samples from runoff, the detention pond system, and pond effluent were collected and analyzed for dissolved and particulate Cu. Copper was the dominant toxic metal for the study site, while analysis of selected samples for Pb and Cd showed these metals to be minor pollutants. Total Cu in runoff varied among different storm events over a wide range of concentrations (< 2 to 33 µg L?1), while total Cu levels in pond effluent remained within a fairly narrow range (5 to 12 µg L?1), Sediment samples collected from the detention pond system were analyzed for Cu in two size fractions (< 63 µm and < 125 µm). Copper was found to be deposited in the pond sediments in a small but highly concentrated plume (up to 130 mg kg?1), extending axially from the runoff inlet pipe. Overall, results from this study showed that low-cost, small-scale detention ponds can be a useful management practice for runoff from parking lot areas and can be of value in preserving the integrity of receiving waters. 相似文献
11.
Daniel N. Subramaniam T. Logeswaran V. Tharshikka B. Nilakshan 《Water, air, and soil pollution》2018,229(9):302
Stormwater biofilters manage quantity and quality of urban stormwater runoff. Particulate solids from natural and anthropogenic sources accumulate on paved surfaces and eventually reach receiving waters. Retention of suspended solids in stormwater management systems ensures the quality of stormwater runoff to water resources. Stormwater biofilters are similar in most of design parameters to sand filters employed in water treatment systems. The understanding and design of stormwater biofilters are often based on generic models of sand filters. Unlike water treatment sand filters, which are continuously fed, stormwater biofilters operate intermittently with spontaneously alternating wetting and drying cycles. This results in dynamic pollutant removal pattern that employs different mechanisms during and across rainfall events. As such, pilot scale biofilter columns fabricated with a layer of organic material were operated. Removal of suspended solids was very dynamic, where impact of age of filter, antecedent dry days, and inflow quality varied during and across events. Flush of retained solids and filter material occurred during the stabilisation period during each event while very high removal percentages (more than 90%) were observed after stabilisation, during an event. Clogging was not observed due to re-entrainment, re-distribution, and flush of retained solids during intermittent wetting and drying cycles. 相似文献
12.
为了方便快速地评估单次径流条件下植被过滤带对污染物氮、磷的净化效果,该文设计了地表径流的模拟放水试验,分析了泥沙与颗粒态污染物的相关性,依据土壤混合层概念简化了土壤污染物的输移,建立了植被过滤带对污染物作用效果的估算模型。结果表明:径流中颗粒态氮、磷含量与泥沙含量有显著相关性(P0.05),据此建立线性相关方程,估算出植被过滤带对颗粒态污染物的净化效果,其86%以上样本的颗粒态氮、磷质量浓度模拟偏差均在±20%之内;溶解态氮、磷的迁移分两部分,即发生于坡面地表径流中和土壤混合层中,分别根据质量平衡原理建立方程对溶解态污染物的迁移进行了模拟,验证得到83%以上样本的溶解态氮质量浓度模拟偏差在±20%之内,67%以上样本的溶解态磷质量浓度模拟偏差也在±20%之内,研究表明,可以基于土壤混合层概念和水文及土壤侵蚀模型对植被过滤带净化效果进行评估。 相似文献
13.
昆明市云龙水库径流区氮磷非点源污染负荷分析 总被引：4，自引：2，他引：2
云龙水库是昆明市最大的城市集中式饮用水源地。水源区农业非点源污染是影响水库水质的主要来源,因此分析水库径流区氮磷非点源污染负荷与来源构成,可为饮用水源区水质保护提供科学依据。采用输出系数模型法,对昆明市云龙水库径流区氮、磷负荷的产生量与入库量进行了估算。结果表明:(1)云龙水库径流区氮、磷非点源污染负荷产生量分别为2079.8和454.32t/a,入库量分别为207.98和24.73t/a。(2)从不同乡镇分析,撒营盘镇的氮、磷负荷产生量最高,云龙乡和茂山镇产出量较低,其余乡镇产生量相近。(3)从不同污染源类型分析,该区非点源污染的主要污染源为农村生活污染和畜禽粪便污染。 相似文献
14.
Bioretention systems are of immense importance as they serve as small “sponges” for cities, cutting stormwater runoff, removing pollution, and using precipitation resources. However, performance data for these facilities are generally lacking, particularly at the field scale. This study investigated the runoff quantity regulation and pollutant removal performance of bioswale and rain garden systems from 2014 to 2017. A performance assessment of these facilities demonstrated that anti-seepage rain garden, bioswale-A, and bioswale-B effectively retained inflow volumes by the filter media, reducing runoff volumes by 54.08, 98.25, and 77.65%, respectively, on average, with only two events of overflowing. According to the water quality data in 24 rainfall events, the main pollutant indexes for the new city include total nitrogen and chemical oxygen demand, and the median values for their respective effluent event median concentrations were 1.29 and 40.13 mg/L for anti-seepage rain garden and 1.68 and 74.00 mg/L for bioswale-B systems. The mean values of pollutant removal of the three bioretention systems, except for infiltration rain garden, were 39.8–59.73% (median?=?54.32%), 61.06–72.66% (median?=?73.47%), and 76.67%–88.16% (median?=?80.64%). Meanwhile, outflow volume of water was found to be most influenced by inflow volumes for the bioswales and anti-seepage rain garden. Mass removals were higher than concentrations owing to water volume attenuation. Based on the data of monitored pollution loads, this study estimated the annual pollutant load removal as 75.45 and 90.7% for anti-seepage rain garden and bioswale-B according to the percent of monitoring rainfall depth in total annual precipitation. This study also established the target pollutant service life model on the basis of accumulated annual load and media adsorption capacity. The results of this study will contribute to a greater understanding of the treatment performance of bioretention systems, assisting in the design, operation, and maintenance of them. 相似文献
15.
Street sweeping is regularly performed within cities and residential communities to reduce roadway debris and ensure properly functioning storm water management systems. Given removal of plant and soil debris, street sweeping may also reduce nonpoint source pollution through removal of leachate source material. To assess the influence of street sweeping on storm water pollutants, 36 storm water collection devices were installed within six residential communities in Central Florida and subjected to varying municipal sweeping regimes. Additionally, precipitation and storm water retention pond leachate samplers were installed to quantify pollutant sources that may enter and leave selected urban communities. Despite high variability in percentage of impervious surfaces, population density, and volume of road debris among communities, no significant (P?≤?0.05) differences were observed for total Kjeldahl nitrogen (TKN), nitrate + nitrite (NOx), and total phosphorus (TP) concentrations in storm water among communities or between swept and unswept areas of roadways. Similarly, no significant differences were observed for TKN, NOx, and TP concentrations in precipitation and storm water. Significant differences in orthophosphate (ortho-P), however, were observed between communities and precipitation. Additionally, storm water TP concentrations were greater than discharge estimated to originate from communities within the study area. Although street sweeping may be effective at reducing volume of roadway debris, our data did not find it reduced N or P in storm water. 相似文献
16.
天然降雨条件下水稻田氮磷径流流失特征研究 总被引：44，自引：15，他引：44
采用具有单排单灌的试验小区,对水稻田在多次天然降雨条件下形成的径流中氮磷的流失特征进行了研究。结果表明,几次降雨径流的累积量中总氮的最高浓度达到22.15mg/L,总磷的浓度达4.84mg/L,可溶态氮是天然降雨径流流失氮素的主要形态,约占总氮的70%～92%,尤其是硝态氮,约占总氮的40%～80%,而径流流失中氨态氮的浓度较小,仅占总氮浓度的3.4%～27%,颗粒态磷在径流流失磷素中占到较大的比重,可达76%～79%;几次降雨事件中总氮的累积流失负荷约在0.23～0.80kg/hm2,总磷的累积流失负荷约在0.07～0.15kg/hm2,两者都小于当季施肥量的1%;降雨和施肥是影响氮磷素径流输出的主要因子,对降雨、施肥量、氮磷素输出负荷运用二元一次方程进行拟合,结果表明相关性达到了显著性水平。 相似文献
17.
几种挺水植物净化生活污水总氮和总磷效果的研究 总被引：27，自引：0，他引：27
研究了石菖蒲、灯心草和蝴蝶花3种不同植被系统、基质为河砂的潜流型人工湿地净化生活污水总氮和总磷的效果,并同无植被系统、相同基质的潜流型人工湿地净化效果进行了比较,结果表明:在较低浓度范围里无植被的人工湿地和3种有植被的人工湿地对污水中总氮有较好的去除作用,随着污水中总氮浓度的增加,虽然无植被的人工湿地和有植被的人工湿地去除总氮的效果均有下降的趋势,但有植被的人工湿地仍然能维持较高的总氮去除水平,无植被的人工湿地总氮去除效果则下降较快。在有植被的人工湿地中,以石菖蒲植被人工湿地氮素净化能力最强,其次为灯心草和蝴蝶花,这与植被自身吸收同化污水中氮素水平以及植物根系微生物作用有关。对于污水中总磷的去除,本研究中由于污水中磷素浓度较低,无植被和有植被的人工湿地对污水中磷素均有很好的去除作用,没有明显差异,但不同的植物体中磷素仍有明显的吸收同化富集现象,其中石菖蒲吸收同化磷素能力最强,其次为蝴蝶花和灯心草,植被在人工湿地系统中对于污水中总氮和总磷的去除起着重要的作用。 相似文献
18.
为了考察负荷变化对渗滤系统拦截削减农业径流污染物性能的影响,在重庆市万州高峰镇鹿山河旁建立多级渗滤系统,开展了农业径流污染物净化效果的试验研究。结果显示,系统对污染物具有较好的去除效果,对化学需氧量(COD)、氨氮(NH4+-N)、总氮(TN)和总磷(TP)的平均去除率分别为35%、73%、37%和54%。污染物出水浓度随进水负荷的升高而升高,具有明显的线性关系。单位面积污染物去除负荷与进水负荷近似服从对数关系,低进水负荷时系统运行稳定,高进水负荷时系统污染物去除负荷波动较大。随着渗滤系统级数的增加,污染物出水负荷和去除负荷沿程上均体现出逐渐降低的趋势。渗滤系统沿程污染物负荷的变化兼具滨岸缓冲带、植被过滤带和生物接触氧化池的特点。 相似文献
19.
自然降雨条件下秸秆还田对巢湖流域旱地氮磷流失的影响 总被引：8，自引：2，他引：6
本文通过野外径流小区观测试验,开展了自然降雨条件下秸秆覆盖对巢湖流域旱地地表径流、泥沙和氮磷流失影响的研究。试验结果表明,秸秆覆盖能有效减少地表径流量、侵蚀产沙量以及因地表径流引起的土壤氮磷流失。在整个玉米生长期间,秸秆覆盖小区的总产流量与产沙量比传统耕作小区分别减少30.47%和22.88%,表现出显著的水土保持作用。与传统耕作小区相比,秸秆覆盖小区随地表径流迁移的氮、磷流失总量分别降低27.42%和32.29%,但秸秆覆盖对径流中氮磷浓度的影响却不明显。溶解态氮是氮素流失的主要形态,颗粒态磷是磷素流失的主要形态。秸秆覆盖可以作为源头控制农业面源污染的较好措施之一加以推广。 相似文献
20.
采用田间小区定位试验研究自然降雨条件下稻麦两熟农田"稻季-麦季-稻季"茬口衔接期养分径流流失规律。结果表明:麦季常规施肥条件下麦稻茬口衔接期径流水量达77.59m3/hm2,径流侵蚀泥沙量达48.30kg/hm2,麦季少免耕处理较常规施肥处理增加径流水量达41.41%;径流水氮磷浓度分别达2.22,0.46mg/L,径流侵蚀泥沙氮磷浓度分别达1.15,1.65g/kg;麦稻茬口衔接期氮素径流流失量达227.84g/hm2,以径流水流失为主,占氮素总径流流失量的75%以上;磷素径流流失量达115.57g/hm2,以径流侵蚀泥沙流失为主,占磷素径流流失总量59%以上;麦季秸秆还田、秸秆还田减肥处理减少麦稻茬口衔接期氮素和磷素径流流失量分别达6.04%～9.74%和5.73%～11.54%,而麦季少免耕处理则增加21.75%和13.42%。 相似文献