Mineral and Anthropogenic Indicator Inorganics in Urban Stormwater and Snowmelt Runoff: Sources and Mobility Patterns

Inorganic chemicals in urban stormwater and snowmelt runoff originate from catchment geology and anthropogenic activities. The occurrence, partitioning and mobility of six minerals and six trace metal (TM) indicators of anthropogenic activities were studied in stormwater, snowmelt and baseflow in four urban catchments, and the sampling of inorganics was supplemented by measurements of electrical conductivity (EC), pH and total suspended solids (TSSs). Minerals occurred at concentrations several orders of magnitude higher (1–10² mg/L) than those of TMs (10^?2–10² μg/L) and reflected the composition of local groundwater seeping into sewers. Concentrations of Ca, K, Mg and Na were enhanced by baseflow contributions and followed closely the electrical conductivity. Al and Fe minerals occurred in insoluble forms, and their pollutographs were similar to those of TMs, whose concentrations mimicked, to some extent, the flux of TSS. The TMs with the highest and lowest particulate fractions were Cr&Pb and Cu&Zn, respectively. The concentrations of total TMs in snowmelt were two to four times higher than those in stormwater, and both sources likely exceeded some of the stormwater effluent limits (for Cd, Cu and Zn) proposed in Sweden. Where such concentrations depended on water hardness, the risk of toxicity might be reduced by elevated hardness of the monitored snowmelt and stormwater. Recognizing the good ecological status of the study area receiving water, Lake Storsjön, some protection against polluted runoff and snowmelt may be needed and could be achieved by implementing stormwater management measures controlling TSS and TMs.     

春季解冻期白浆土融雪侵蚀模拟研究

采用室内人工模拟融雪水冲刷试验,研究了春季解冻期冻融温差、循环次数、土壤初始含水率、融雪水流量和解冻深度这5个控制因子对白浆土侵蚀的影响。结果表明,影响土壤侵蚀的首要因素为融雪水流量。春季解冻期土壤发生侵蚀主要集中在前15次冻融循环过程中,之后即使冻融循环次数增加,侵蚀量增幅也不明显。土壤含水率变化与侵蚀量之间线型关系不明显,初始含水率较小的土壤侵蚀量大于初始含水率较大的侵蚀量。在径流冲刷过程中,融雪流量的大小和土壤冻层的存在,共同影响解冻深度与侵蚀量大小之间的关系。当融雪流量较小时,土壤解冻深度越小侵蚀量越大,二者间呈负相关关系;反之,当融雪流量较大时,土壤解冻深度与侵蚀量之间呈正相关关系。     

松花江流域融雪径流及其影响因素

[目的]定量分析松花江融雪径流变化过程,并探讨降雪量、温度、辐射等因素对融雪径流的影响,为松花江流域融雪径流调控和利用提供依据。[方法]采用Mann—Kendall检验、移动平均、斜率估计等方法,对松花江流域1956—2010年的降雪、气温、辐射、径流量等进行分析。[结果](1)春季解冻期松花江径流量介于1.26×108~1.20×1010 m3/a,且呈减小趋势;(2)该时段流域内气温上升明显,增加幅度达0.047℃/a,大于年平均温度变化幅度0.036℃/a;(3)辐射值在研究期内呈现减小趋势,多年平均及解冻期辐射值降幅分别为5和8J/(m2·a);(4)降雪量逐年增加,从流域降雪量分布来看,松花江干流自东向西递减,松花江上游支流嫩江流域降雪量自北向南降雪量逐渐减小。降雪量与融雪径流变化一致。[结论]温度升高为融雪创造条件的同时也增强了蒸发作用,而降雪量的增加并不足以抵消温度对融雪的影响。     

锡林河流域融雪径流时间变化特征与成因分析

融雪径流是寒旱区草原流域径流的重要补给方式和水源。融雪径流时间随着气象条件的变化而改变,这严重影响着研究区年径流量和各季径流量的分配。采用锡林河水文站1960—2009年水文年流量质心时间CT来表示锡林河水库上游融雪径流开始时间,分析了融雪径流时间变化特征。结果表明:锡林河水文站融雪径流时间具有提前趋势,且融雪径流发生在3月末与4月初期,锡林浩特气象站融雪期（3—4月）气温升高或积雪期（上年10月—当年4月降水量增加,锡林浩特水文站融雪径流时间会提前,但融雪期气温对融雪径流时间作用更明显。由融雪径流时间与年径流量和四季径流量的相关关系,可得融雪径流时间提前,年径流量、冬、夏、秋季径流量均会减小,而春季径流量会增大,但融雪径流时间与年径流量、夏、秋季径流量关系最为密切,相关系数分别为0.456,0.600与0.676。这对寒旱区草原流域合理利用雪水资源和洪水预警有重要作用。     

干旱区季节性冻土冻融状况及对融雪径流的影响

利用天山北坡季节性冻土区的军塘湖流域观测场2013年和2014年冻融期冻土深度及各层土壤的温湿度数据,研究季节性冻土的冻融规律及冻融过程中土壤含水量的变化特征,探讨各层土壤水分分布及迁移特征对融雪径流的影响。结果表明:冻融过程中冻土深度会发生变化,且温度不同冻融速率不一;土壤水分的迁移受制于土壤温度的变化,特别是表层10cm土壤温湿度相关性极大;对比2013年,2014年数据,土壤表层10cm内的含水量变化会对融雪水的下渗有调控作用,从而影响下垫面的径流量。研究季节性冻土冻融过程及对融雪径流的影响,会对准确预报融雪性洪水有重要意义。     

Conditions of Snowmelt Runoff Formation on Slopes in the South of the Volga Upland

Eurasian Soil Science - The aim of the research was to determine the factors influencing the surface runoff of meltwater formation on the slope in the agroforestry landscapes in the southern part...     

玛纳斯河流域融雪径流与积雪-气象因子分析

利用雪盖、径流、气象因子数据分析了玛纳斯河流域融雪径流特征及其与积雪-气温-降雨的关系。根据地形、植被和积雪分布特征建立了流域分带体系。以2000-2008年3-6月8日合成MODIS积雪产品（MOD10A2）为基础,插值获取流域分带日均积雪面积数据。根据天山山区气温-降雨的垂直地带性特征,以肯斯瓦特水文站1995-2008年逐日气温、降水数据为数据源,应用DEM递推获取流域分带日均气温、降水数据。定性分析了流域各带气温、降雨和积雪分布特征及其定量相关关系。同时,分析了流域积雪面积和径流的定量关系。结果表明:①低山荒漠草原带3月22号前后,云杉林带4月11号前后,高山高寒草甸带5月14号前后,高山冰雪带6月12号前后气温持续在零度以上;②降水年内分配不均,降水主要集中在夏季,占年降水量的43.39% ,春季占28.14% ,秋冬季降雨偏少,分别为13.04%和15.24%;③各带积雪面积和气温相关性很高,3-6月各带气温逐渐升高,积雪逐渐融化,除高山冰雪带不完全消融外其余分带积雪在此期间全部消融;高山高寒草甸带和高山冰雪带积雪面积和气温呈线性相关;④流域总的积雪面积和径流散点图显示出很好的幂指数相关;不同年,积雪面积与径流关系呈规律性变化。     

A Cost-Effective Methodology for Spatial Concentration Distributions of Urban Air Pollutants

A methodology to determine economically the spatial concentration distribution of the air pollutants of carbon monoxide (CO), sulphur dioxide (SO₂), nitrogen monoxide (NO), nitrogen dioxide (NO₂), oxides of nitrogen (NO_x) and traffic rates (TR) is described. It involves the immediate transfer of samples from field to analysers for measurement and a subsequent statistical treatment. The proposed methodology has been applied in Patras using 5 and 50-l Teflon air sample bags, sampling at least 12 to 36-l actual volumes within a 20-min time interval. Totally, 221 pairs of 5-l and 112 single 50-l samples were randomly picked in morning rush hours of working days from 64 locations of a 40.0-km² area during a winter period, when peaks of primary air pollutants usually occur due to high traffic rates and systematic inversions. Measurements were used to statistically calculate spatial average levels approximating 1-h mean concentrations with acceptable mean probable errors less than 25 % for indicative random sampling. The 1-h levels were strongly correlated to the corresponding traffic rates. Iso-concentration diagrams indicated possible zones susceptible to high pollution levels and helped to check the location appropriateness of the existing monitoring stations for (a) fixed urban-background measurements at the Vas. Georgiou A’ Sq., which was ideal, and (b) fixed traffic-oriented measurements, which should be relocated to the Ipsilon Alonion Sq. In addition, data helped to determine other points where indicative measurements should be performed. Data could be very useful for the Patras air quality assessment in conjunction with model predictions and/or objective estimation methods.     

东北黑土区融雪径流侵蚀力时空分布

[目的] 融雪侵蚀是东北黑土区主要土壤侵蚀形式之一,是该区土地退化的重要作用力,融雪径流侵蚀力是计算融雪径流侵蚀量的关键因子,因此研究融雪径流侵蚀力具有重要意义。融雪径流侵蚀力主要受积雪深度、辐射强度及升温速率影响,其主要驱动力包括融雪速率和地表径流作用。[方法] 通过计算近31年日均融雪径流侵蚀力,分析东北黑土区融雪径流侵蚀力时空分布特征,并利用地理探测器辨析各区域融雪径流侵蚀力的主要影响因子。[结果] 3个黑土亚区1990—2020年日均融雪径流侵蚀力均呈现先增大后减小态势,近些年逐步趋于稳定,多年日均融雪径流侵蚀力为0.01 (MJ·mm)/(hm²·h·a);空间上多年日均融雪径流侵蚀力在0~0.21 (MJ·mm)/(hm²·h·a)范围内,基本呈现中间小、四周大规律。融雪径流侵蚀力影响因子空间上表现为积雪深度北部大、南部小,太阳辐射强度呈现由西向东递减,升温速率值从北部向南部递减。通过地探测器辨析融雪径流侵蚀力影响因子作用强弱发现,升温速率对蒙东黑土亚区作用最强,而积雪深度对松嫩黑土亚区及三江黑土亚区作用最强。[结论] 通过分析1990—2020年东北黑土区融雪径流侵蚀力时空特征及其影响因子,对于深化研究区融雪径流侵蚀特征及融雪侵蚀防控具有一定的理论和实践意义。     

Characterizing Dry Deposition of Mercury in Urban Runoff

Stormwater runoff from urban surfaces often contains elevated levels of toxic metals. When discharged directly into water bodies, these pollutants degrade water quality and impact aquatic life and human health. In this study, the composition of impervious surface runoff and associated rainfall was investigated for several storm events at an urban site in Orlando, Florida. Total mercury in runoff consisted of 58% particulate and 42% filtered forms. Concentration comparisons at the start and end of runoff events indicate that about 85% of particulate total mercury and 93% of particulate methylmercury were removed from the surface before runoff ended. Filtered mercury concentrations showed less than 50% reduction of both total and methylmercury from first flush to final flush. Direct comparison between rainfall and runoff at this urban site indicates dry deposition accounted for 22% of total inorganic mercury in runoff.     

东北黑土区融雪径流对流域产沙的贡献及因素分析

[目的]揭示流域融雪期径流产沙特征及对全年总产沙的贡献,阐明东北黑土区影响融雪期产沙贡献的主控因素,并进而为东北黑土区流域综合治理提供科技支撑。[方法]基于东北地区203个气象站点数据以及15个流域水文站点径流泥沙资料,通过提取流域降水、地形、气候、土壤和土地利用等因子,采用多因素相关分析的方法,开展融雪期产沙贡献影响因素研究。[结果]东北黑土区不同流域年均降雪量占年均降水量的比例为3.7%～23.9%,空间分布差异较大,呈东南多、西北少的分布特点。融雪期径流深占全年径流深比例为13.7%～32.5%,融雪期产沙量对全年产沙量的贡献3.8%～23.47%,融雪期产沙模数占全年产沙模数的3.1%～35.9%,且它们空间分布规律性差。年均降水量、降雪量占降水量比例、融雪期径流深占全年径流深比例3个因素与融雪期产沙贡献在0.05的水平上呈显著相关。降雪量占降水量比例对流域融雪期产沙量和产沙模数的贡献率分别为25.41%和30.22%。最大高程对流域融雪产沙量和产沙模数的贡献率分别为24.36%和20.38%。[结论]东北区融雪期产沙对流域全年产沙有较大贡献,且受多重因素影响,未来应加强融雪期的侵蚀产沙观测研究。     

土壤对城市雨水径流中污染物的削减作用

[目的]分析城市雨水径流在土壤中的净化情况及径流污染物对土壤环境造成的影响。[方法]在充分了解陕西省西安市某地土壤特性和当地雨水径流水质的基础上,模拟城市土壤表层系统和雨水径流装置,研究雨水径流中的污染物在下渗过程中土壤表层对它们的削减作用及土壤基本理化性质的变化。[结果]在土壤层厚度为20cm,雨水渗透量为6 000ml,径流时间3h的条件下,裸土和绿地表层土壤对模拟雨水中各污染物的去除率均达到40%以上;土壤的密度及pH值基本未发生变化,氮的含量由原土的54.95mg/kg分别增加到65.10(绿地)和68.60mg/kg(裸土),有效磷的含量由原土的59.23mg/kg变化到82.39mg/kg(裸土)和39.93mg/kg(绿地),有机质的含量由原土的18.32mg/kg变化到19.28mg/kg(裸土)和14.04mg/kg(绿地)。[结论]绿地对雨水径流处理效果较好。在渗流过程中,土壤对氨氮的截留效果较为明显,短时间内土壤基本物理性质变化不大。     

天山北坡中段融雪径流敏感性分析——以军塘湖流域为例

以天山北部中段军塘湖为典型研究区,利用军塘湖河流域径流和气象数据分析了高山融雪径流与温度、降雨的定量关系。基于天山北坡中段10个气象站(乌苏、石河子、沙湾、玛纳斯、呼图壁、昌吉、米泉、小渠子、大西沟、天池)1961—2010年逐月气温、降水数据等实测数据为基础进行Mann—Kendall趋势检验与分析。以模比系数差积曲线在M—K检验基础上分析径流、温度与降水之间的趋势关系。以SWAT模型为框架建立新疆军塘湖河流域水文过程模型,利用红山水库12a径流数据在SWAT模型参数校准后对新疆天山北坡融雪径流过程进行敏感性分析预测。通过改变SWAT模型输入数据的平均温度、降水量等因素分析了其对融雪径流的敏感性及影响。结果发现,从冬季至初春温度及降水等因素变化仅在融雪期对径流产生较大影响。此外,温度数据的变化对军塘湖天山北坡流域融雪径流的影响较降水量大。     

A Traditional Analysis of the First Flush Effect for Nutrients in Stormwater Runoff from Two Small Urban Catchments

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.     

不同空间布局对城市降雨径流的影响

[目的]探讨不同城市空间布局(包括分析绿地、建筑)分别到出水口不同水流长度、面积比等因素与降雨径流的关系,以优化城市典型下垫面的空间布局,实现城市雨水径流的控制。[方法]以漯河市中心城区为研究对象,基于2016年3月航拍影像,提取中心城区的土地覆被信息,利用SWMM模型分析研究区在不同降雨重现期的径流特征以及影响降雨径流的因素,并定量研究城市绿地、建筑不同空间分布格局对径流削减的影响。[结果]绿地、建筑面积比与径流系数呈极显著负相关,二者到出水口的水流长度对产流效应有较显著影响,绿地较建筑离出水口近的子汇水区径流系数较小,其中重现期为5a时,径流削减率最高可达到44.49%。[结论]结合水流长度、面积比等因素,合理安排绿地、建筑的规模及布局,可实现雨水空间再分配,从而达到削减径流的目的。     

Technical and Environmental Functioning of Detention Ponds for the Treatment of Highway and Road Runoff

Based on an inventory of more than 200 facilities for the treatment of road runoff water in Sweden, 26 representative stormwater ponds were studied with regard to technical function, maintenance and metal accumulation. Sediment accumulation and metal content in the pond sediment was studied in relation to concentration in the runoff water, spatial variation and pond geometry. It emerged that the pollution retention capacity was not optimal for many of the ponds. The observed sediment thickness was low reflecting turbulent conditions and that much of the pollutants are transported through the ponds. Statistical tests performed on 15 ponds showed a significant relationship between metal content in sediment and pond size while pond shape was found to have no effect on accumulation rate. There is still significant potential for the development of the design and technical function of the ponds, e.g. design elements such as pre-settlement trench and elements for enhancing high hydraulic efficiency. Disturbance of the technical function, in terms of clogging of pipes, erosion, flooding etc. was reviewed for three of the ponds, however only 50% of the ponds did show some form of documented maintenance-program. This generates an obvious threat to the effective long-term function of these ponds.     

Granulometry of Non-colloidal Particulate Matter Transported by Urban Runoff

Water, Air, & Soil Pollution - This study examined the granulometry of non-colloidal particulate matter (PM) from four urban transportation land use catchments (source areas) in Baton Rouge,...     

Urban Runoff Impacts on Particulate Metal Concentrations in River Seine

Metallic contents (Cd, Cu, Pb, Zn) of suspended solids (SS) were measured in two sites (Suresnes and Chatou) in the river Seine, downstream Paris, during three summer periods. These two sites, which are respectively located downstream and upstream two of the most important combined sewer overflows (CSO's) of the Parisian sewer system (Clichy and La Briche), allow us to assess these CSO immediate impacts. Samples were collected using sediment traps, weekly during dry weather and daily during the week following the major CSO's events. The heavy metal concentrations, relatively large but stable during summer periods, were shown to further increase downstream Paris after main rain discharges occurred. Metal concentrations measured within the Seine SS during rain events, allowed us to establish that the observable immediate impact of Clichy overflows is only 5% of what it could be. The general principle demonstrated through this work is that most SS originating from CSO's rapidly settle once they reach the river. These polluted particles greatly contribute to the SS chronic pollution downstream Paris during dry weather, through a slow resuspension mechanism of the deposited sediments.     

融雪期季节性冻土湿度变化对融雪洪水的影响

利用天山北坡军塘湖流域2009、2010年春季融雪期季节性冻土湿度、雪深及流量数据,对春季融雪洪水与季节冻土的湿度变化进行分析,结果发现:(1)融雪期融雪洪水的流量与雪深、季节性冻土的湿度具有密切的关系,雪深及季节性冻土的湿度决定着融雪洪水峰值变化;(2)季节性冻土表层10 cm范围内湿度的变化会导致融雪洪水的产生,而10 cm以下季节性冻土的湿度剧烈变化引起融雪水的下渗而削弱了洪峰、降低了峰值.季节性冻土湿度的变化改变了下垫面的产流方式,研究季节性冻土湿度变化对融雪洪水的影响,对春节融雪洪水的预报具有重要意义.     

Surface Runoff and Snowmelt Infiltration into the Soil on Plowlands in the Forest-Steppe and Steppe Zones of the East European Plain

Long-term series of observations over the spring water balance elements on fields with hydrologically contrasting agricultural backgrounds―a loose soil after fall moldboard plowing and a plowland compacted by 12–16% compared to the former soil (perennial grasses, winter crops, stubble)―have been analyzed. The values of surface runoff and water infiltration into the soil in the steppe and forest-steppe zones of European Russia have been calculated for the spring (flooding) period and the entire cold season. The hydrological role of fall plowing has been shown, and water balance elements for the current (1981–2016) and preceding (1957–1980) periods have been compared. A significant decrease in runoff and an increase of water reserve in the soil have been revealed on all plowland types. Consequences of changes in the spring water balance on plowland have been analyzed.