Estimation of Suspended‐Sediment Concentration From Total Suspended Solids and Turbidity Data for Kentucky, 1978‐19951

Williamson, Tanja N. and Charles G. Crawford, 2011. Estimation of Suspended‐Sediment Concentration From Total Suspended Solids and Turbidity Data for Kentucky, 1978‐1995. Journal of the American Water Resources Association (JAWRA) 47(4):739‐749. DOI: 10.1111/j.1752‐1688.2011.00538.x Abstract: Suspended sediment is a constituent of water quality that is monitored because of concerns about accelerated erosion, nonpoint contamination of water resources, and degradation of aquatic environments. In order to quantify the relationship among different sediment parameters for Kentucky streams, long‐term records were obtained from the National Water Information System of the U.S. Geological Survey. Suspended‐sediment concentration (SSC), the parameter traditionally measured and reported by the U.S. Geological Survey, was statistically compared to turbidity and total suspended solids (TSS), two parameters that are considered surrogate data. A linear regression of log‐transformed observations was used to estimate SSC from TSS; 72% of TSS observations were less than coincident SSC observations; however, the estimated SSC values were almost as likely to be overestimated as underestimated. The SSC‐turbidity relationship also used log‐transformed observations, but required a nonlinear, breakpoint regression that separated turbidity observations ≤6 nephelometric turbidity units. The slope for these low turbidity values was not significantly different than zero, indicating that low turbidity observations provide no real information about SSC; in the case of the Kentucky sediment record, this accounts for 30% of the turbidity observations.     

PATTERNS OF SUSPENDED SEDIMENT TRANSPORT IN A COASTAL ALASKA STREAM1

Suspended sediment data from a 154 ha watershed on northeast Chichagof Island, Alaska, were collected over three fall storm seasons from 1980 to 1982. Sediment rating curves for nine pooled storms explained less than 34 percent of the variation in total suspended solids (TSS). Significantly higher concentrations of suspended sediment occurred during the rising limb of storm hydrographs than for similar flows on the falling limb, accounting for hysteresis loops in TSS versus streamflow plots for individual storms. These hysteresis loops were wider during early season storms, indicating that easily transportable fine sediment may have been flushed from the upper portion of channel banks and from behind large organic debris during early season peak flows. Regression relationships (TSS versus Q) developed for the highest stormflows (> 1 m³/s) had steeper slopes than the lower stormflows (< 1 m³/s). Turbidity correlated well (r=0.94) with TSS for all storm-flow data combined. Organic matter constituted an average of 35 percent (by weight) of TSS for all water quality samples.     

Evaluating Cover Crops (Sudex,Sunn Hemp,Oats) for Use as Vegetative Filters to Control Sediment and Nutrient Loading From Agricultural Runoff in a Hawaiian Watershed1

Abstract: A study was conducted to determine the effects of three land covers (sunn hemp –Crotalaria juncea, sudex, a sorghum‐sudangrass hybrid –Sorghum bicolor x S. bicolor var. sudanese, and common oats –Avena sativa) planted as vegetative filter strips on the reduction of sediment and nutrient loading of surface runoff within the Kaika‐Waialua watershed on the island of Oahu, Hawaii. Runoff samples were collected and analyzed for total suspended solids (TSS), total dissolved solids (TDS), phosphorous, and three forms of nitrogen (nitrate, ammonium, total nitrogen). Study results show that during seven out of 10 runoff events, the three cover crop treatments significantly reduced TSS as compared to the fallow treatment. Average removal efficiencies were 85, 77, and 73% for oats, sunn hemp, and sudex, respectively, as compared to the fallow treatment. Nutrient concentrations were low with phosphorous concentrations, lower than 1 (μg/ml) for all treatments, and total nitrogen (TN) concentrations below 7 (μg/ml) except in the sunn hemp treatment, where TN concentrations were less than 10 (μg/ml). Results of analysis of TDS showed that the cover crop treatments did not decrease dissolved solids concentrations in comparison with the fallow treatment. Analysis of nutrient concentrations in runoff samples did not detect any significant decreases in phosphorous, nitrogen, ammonium, or TN concentrations in comparison to the fallow treatment. However, a significant increase in TN concentrations in the sunn hemp treatment was detected and showed the nitrogen fixing capacity of sunn hemp. No treatment effects on runoff volume were detected, and runoff volumes were directly correlated with rainfall amounts showing no crops significantly impacted soil infiltration rates. These results were attributed to extremely low soil hydraulic conductivities (0.0001‐7 cm/day at the soil surface, 15 and 30 cm below the soil surface). This study showed that cover crops planted as vegetative filters can effectively reduce sediment loads coming from idle and fallow fields on moderately steep volcanically derived highly weathered soils.     

取样及样品前处理对制革废水中总铬的影响

通过利用火焰原子吸收分光光度法测定制革企业不同工艺流程产生废水的总铬,考察不同量具及取样量、不同消解方法和样品保存期限对测定结果的影响。结果表明水样中悬浮物造成的取样不均匀性导致测定结果差异明显,不同消解方法测定制革废水总铬,检测数据具有可比性,固定剂的加入能够使得水样检测数据保持稳定。     

"钼酸铵显色-离心分离光度法"测高悬浮物地表水中总磷的方法探讨

本文对高悬浮物地表水中总磷测定方法进行了探讨,提出了用“钼酸铵显色-离心分离法”解决由于高悬浮物所带来的分析误差。通过实验室大量样品分析实验,证明此方法的可行性。     

人工湿地对污染物去除的研究现状及发展前景

人工湿地是近年兴起的高效、经济、环保型的污水处理方式。在前人研究的基础上本文对人工湿地去除非点源污染物中的总氮、总磷、总悬浮物的研究现状及设计湿地的植物和填料对去除污染物影响方面进行了概述，并对其今后研究发展的趋势作了探讨。     

Modeled Summer Background Concentration of Nutrients and Suspended Sediment in the Mid‐Continent (USA) Great Rivers1

Angradi, Ted R., David W. Bolgrien, Matt A. Starry, and Brian H. Hill, 2012. Modeled Summer Background Concentration of Nutrients and Suspended Sediment in the Mid‐Continent (USA) Great Rivers. Journal of the American Water Resources Association (JAWRA) 48(5): 1054‐1070. DOI: 10.1111/j.1752‐1688.2012.00669.x Abstract: We used regression models to predict summer background concentration of total nitrogen (N), total phosphorus (P), and total suspended solids (TSS), in the mid‐continent great rivers: the Upper Mississippi, the Lower Missouri, and the Ohio. From multiple linear regressions of water quality indicators with land use and other stressor variables, we determined the concentration of the indicators when the predictor variables were all set to zero — the y‐intercept. Except for total P on the Upper Mississippi River, we could predict background concentration using regression models. Predicted background concentration of total N was about the same on the Upper Mississippi and Lower Missouri Rivers (430 μg l^?1), which was lower than percentile‐based values, but was similar to concentrations derived from the response of sestonic chlorophyll a to great river total N concentration. Background concentration of total P on the Lower Missouri (65 μg l^?1) was also lower than published and percentile‐based concentrations. Background TSS concentration was higher on the Lower Missouri (40 mg l^?1) than the other rivers. Background TSS concentration on the Upper Mississippi (16 mg l^?1) was below a threshold (30 mg l^?1) designed to protect aquatic vegetation. Our model‐predicted concentrations for the great rivers are an attempt to estimate background concentrations for water quality indicators independent from thresholds based on percentiles or derived from stressor‐response relationships.     

紫外分光光度测定总氮的影响因素探讨

本文介绍了测定总氮过程中,不同消解方法、碱性过硫酸钾的稳定时间、悬浮物粒径对总氮测定的影响。实验表明:碱性过硫酸钾避光在冰箱中至少可保存一个月,悬浮物粒径对总氮的测定无影响,消解总氮时,可在压力锅加热到120℃开始计时,恒温消解30分钟,自然冷却。     

城市污水处理厂出水的化学需氧量和悬浮物的相关关系以及悬浮物测定方法探讨

以活性污泥法为基础的二级生化处理工艺是城市污水处理的基本方法，其出水的化学需氧量值(CODCr)不仅大于悬浮物(SS)值，而且两者之间还存在着一致性的相关关系。本文对这种关系作了相应探讨。同时对悬浮物的测定方法进行了探讨，提出了悬浮物的表示由可沉固体 透明度的概念。     

日照市地下水总硬度与溶解性总固体的关系

对日照市不同类型地下水总硬度与溶解性总固体监测数据进行分析并建立二者之间的回归方程。分析结果表明:四种类型地下水总硬度与溶解性总固体之间存在着良好的相关性:碳酸盐类裂隙岩溶水、碎屑岩类孔隙裂隙水、基岩裂隙水和松散岩类孔隙水的总硬度与溶解性总固体的相关系数分别为0.981,0.973,0.971和0.953。     

ADSORPTION OF PHOSPHATE BY RIVER PARTICULATE MATTER1

ABSTRACT: The adsorption of phosphate on particulate matter from the Illinois and Spoon Rivers was investigated. Adsoprtion reached equilibrium after 5 to 6 days and adsorption isotherms were linear for both constant and varying amounts of particulate matter. Adsorption was maximum at pH 8.3 – 8.4 and minimum at 6.0. Rates of adsorption were influenced by the equilibrium concentration of phosphate-P and were essentially the same for the Illinois and Spoon Rivers. However, the quantity of phosphate-P adsorbed per unit weight of particulate matter differed for the two streams with that in the Illinois River exhibiting an adsorption capacity 7 times that of the Spoon River.     

污水处理系统中悬浮物形成机理与处理方法

文章以风城油田稀油污水处理为例,分析污水处理系统中悬浮物的形成机理,并对污水含油、悬浮物、固体含量、粒径中值、聚合物含量、细菌、温度、硫化物、二价铁、pH值等水质指标进行分析,找出影响污水处理的主要因素,并对油水悬浮物处理方法进行室内分析及现场物理、化学方法实践,解决污水处理系统中悬浮物问题。     

滤筒法测定水中悬浮物的实践

采用重量法用滤筒替代滤膜进行测定水中悬浮物的比对实验,实验结果表明:滤筒测定水中悬浮物比滤膜测定水中悬浮物更具有易恒重、测定误差小、准确度高、快速、简便、成本低等优点,适合水质监测应用。     

TOTAL SOLUTES LOADS AND GEOCHEMICAL YIELDS IN THE SASKATCHEWAN RIVER BASIN1

ABSTRACT: River solute loads have seldom been measured in very large, complex drainage basins, nor have the methods of calculating loads been critically examined. For sites in the Saskatchewan River Basin, Canada, rating curves were poor predictors of solute loads because correlations between discharge and total solutes concentration were weak (R² < 0.05 in most cases) and suffered from hysteresis. In contrast, the interval method produced reliable estimates in all seasons and sites tested, and was little affected by sampling schedule. The limit of precision (SE) for estimates of mean annual or seasonal solute load was 10–15 percent of the mean (5 percent in very small basins), reached with 10 years or more of data. Two-thirds or more of total annual solute load was transported during the open-water season, but the proportion carried during winter increased from 8 percent to 34 percent from the upstream to the downstream end of the basin, due to reservoirs retaining and mixing water. Annual loads of total solutes varied from 6.2 × 10⁴ tonnes in foothills tributaries to almost 4.0 × 10⁶ tonnes in the Saskatchewan River near the mouth. But, on an areal basis, the mountain and foothills region was the dominant solute source, producing 43–97 tonnes/km²/yr, compared with only 3–22 tonnes/km²/yr for prairie rivers. This difference is a consequence of greater rainfall and, hence, more rapid erosion in the mountains.     

ENVIRONMENTAL FACTORS INFLUENCING SUSPENDED SOLIDS IN THE LOXAIIATCHEE ESTUARY,FLORIDA1

ABSTRACT: A study was initiated to examine the effects of wind speed, wind direction, freshwater inflow, and tide height on suspended solid concentration and distribution in the Loxahatchee estuary, Florida. Recent efforts to increase freshwater flows in this system raised concerns that suspended solid concentrations would increase as well, which might result in negative impacts for the estuary. The data indicated that total suspended solids (TSS) in the estuary are derived primarily from the inlet and not from freshwater tributaries. In addition, total suspended solids and volatile suspended solids were correlated strongly with salinity, suggesting that suspended sediments act conservatively throughout this system. No one environmental factor had an overwhelming influence on suspended solid concentration throughout the estuary; different regions of the estuary were influenced by different factors. Freshwater inflow was negatively related to TSS in the upper reaches of the estuary but was positively related to TSS in the central embayment region of the estuary. We attribute this latter finding to the fact that extremely high inflows both prevented the normal transport upstream of tidal borne suspended sediments and promoted mixing when the freshwater front moving downstream confronted the tidal front moving upstream. Wind speed, wind direction, and tide height had relatively small effects on TSS concentration but were most influential in reaches upstream of the central embayment, where tidal velocity begins to diminish.     

青冰滩冰川水文特征初步分析

通过对青冰滩冰川的综合考察,对该地区2008-08-01日至08-31日的水文、气象以及水环境进行了连续观测。结果表明:冰川表面大量覆盖冰碛增加了冰川表面的反射率,加速了冰川消融;整个8月日均气温在8℃以下,气温的日较差较大,冰川消融期的降水以降雪和冰雹为主;冰川融水的电导率和溶解性固体相关系数可达0.98,两者与气温的相关度也可达到0.8以上。     

超声粉碎-TOC/TN仪法直接测定污水处理厂废水中的总氮

污水处理厂废水经超声粉碎后,使用TOC/TN仪直接测定总氮.对仪器条件、进样方式、微波粉碎时间及加标回收率进行了探讨.相对标准偏差＜2.35％,测定结果与国标法一致,相对误差＜±1.3％,回收率为95.3％ ～97.8％.方法简便、快速、准确.