稻田种植对地表径流污染状况调查研究

以辽宁省营口市水稻种植区为研究区域,通过对监测地块实地调研、资料收集、监测分析,在稻田整个作物生长周期化肥、农药的施加等情况下开展氮、磷污染物对地表径流污染状况的调查研究.结果表明:化肥、农药的施加均会使受纳水体中总磷、总氮质量浓度升高,施肥后总氮质量浓度上升最显著,绿色种植在扣除总氮背景值后达到37.7 mg/L,有...     

施肥和秸秆覆盖对成都平原区农田氮和磷流失的影响

近年来由于氮、磷肥料过量施用造成了严重的污染问题和富营养化现象,而且这种污染问题在稻田区域更加明显.因此,采用田间小区试验方法,通过对2018年和2019年田间实地监测,在自然降雨条件下,对成都平原区不同施肥量以及秸秆覆盖对湿沉降和地表径流氮和磷的影响进行研究.结果表明,湿沉降氮养分主要以铵态氮存在,磷养分主要以可溶性总磷存在,氮和磷沉降主要发生在6～8月这3个月.地表径流量与降雨量呈正比,而地表径流氮养分浓度与降雨量呈反比.在2018年和2019年,增氮处理TR3总氮流失量分别为4.75 kg·hm^-2和2.68 kg·hm^-2,比常规处理TR1流失量增加26.73%和43.32%,是流失量最高的处理;减氮处理TR4总氮流失量分别为2.91 kg·hm^-2和1.37 kg·hm^-2,比常规处理TR1流失量降低了36.33%和26.74%,是流失量最小的处理.优化施肥处理TR2和减氮处理TR4能够有效降低地表径流磷素的流失,集中高强度降雨会降低地表径流总磷中颗粒态磷的含量.氮养分的流失主要集中于7～...     

入库径流污染综合防控技术应用实践——以彭州市西河水库为例

针对彭州市西河水库污染现状及污染来源特征,为有效限制和处理入库径流污染物,结合库区自然条件,集成了"生态护坡—岸边人工湿地—人工浮岛"综合防控技术,并设计建设了示范工程。工程运行监测结果表明:经示范工程处理过的径流来水,除总氮以外,其他指标可以达到地表水Ⅲ类标准要求,其中,来水总氮平均超标63%,出水总氮平均超标24%,工程平均削减总氮23.93%。"生态护坡—岸边人工湿地—人工浮岛"综合防控技术及示范工程在西河水库径流污染防控方面发挥了积极作用,可以为类似水源污染防控提供技术参考。     

A Hydrologic Data Screening Procedure for Exploring Monotonic Trends and Shifts in Rainfall and Runoff Patterns

A thorough understanding of past and present hydrologic responses to changes in precipitation patterns is crucial for predicting future conditions. The main objectives of this study were to determine temporal changes in rainfall‐runoff relationship and to identify significant trends and abrupt shifts in rainfall and runoff time series. Ninety‐year rainfall and runoff time series datasets from the Gasconade and Meramec watersheds in east‐central Missouri were used to develop data screening procedure to assess changes in the rainfall and runoff temporal patterns. A statistically significant change in mean and variance was detected in 1980 in the rainfall and runoff time series within both watersheds. In addition, both the rainfall and runoff time series indicated the presence of nonstationary attributes such as statistically significant monotonic trends and/or change in mean and variance, which should be taken into consideration when using the time series to predict future scenarios. The annual peak runoff and the annual low flow in the Meramec watershed showed significant temporal changes compared to that in the Gasconade watershed. Water loss in both watersheds was found to be significantly increasing which is potentially due to the increase in groundwater pumping for water supply purposes.     

The Comparative Accuracy of Two Hydrologic Models in Simulating Warm‐Season Runoff for Two Small,Hillslope Catchments

This article assesses the performance of two hydrologic models in simulating warm‐season runoff for two upland, low‐yield micro‐catchments near Coshocton, Ohio. The two models, namely the Storm Water Management Model (SWMM) and the Gridded Surface‐Subsurface Hydrologic Analysis (GSSHA), were implemented with contrasting levels of complexity, with the former representing the catchments as lumped spatial units and computing evaporation only from standing water, and the latter incorporating fine‐scale variation in topography and soil properties and computing evapotranspiration from soil based on weather data. Our investigation began with uncalibrated model runs for 1990‐2003 except for 1994 using a priori parameter values. Then a set of calibration experiments were performed wherein the sensitivity of model performance to the length of calibration records was examined. Our results pointed to large errors associated with simulations from both models: even the calibrated models were unable to reproduce the seasonal and between‐catchment contrasts in runoff response. Using a priori parameter values, SWMM attained better results than GSSHA. However, with simple calibration, GSSHA outperformed SWMM in several respects. It was also found that extending the record of calibration rendered relatively minor changes to model performance. The practical and scientific implications of the findings are discussed.     

珠江八大入海口门可溶态铜的时空变化及其影响因素

以1987年至2011年的月测数据为基础,分析了珠江八大人海口可溶态铜的时空变化,并探讨了工业发展、铜矿厂分布、水产养殖及铜消费量等因素对它们的影响。研究结果表明:与国内外其它人海口相比,珠江口可溶态铜的含量处于较高水平,其中,虎门水道(A1)可溶态铜的含量显著高于除鸡啼门水道(A6)外的其它人海口(p0.1),可能是受工业废水排放及铜矿厂分布的影响。在时间变化趋势上,8个采样点之间,除了A1与A4外,其它采样点间均呈显著的正相关性(p0.1),其中A5和A6的变化趋势还与我国的铜消费量具有显著相关性(p0.1),表明人海口之间铜污染可能具有相似的影响因素,且工业生产活动对水体铜污染的波动具有一定的影响。     

Cation exchange resin supported nanoscale zero-valent iron for removal of phosphorus in rainwater runoff

Self-made cation exchange resin supported nanoscale zero-valent iron （R-nZVI） was used to remove phosphorus in rainwater runoff. 80% of phosphorus in rainwater runoff from grassland was removed with an initial concentration of 0.72 mg. L-1 phosphorus when the dosage of R-nZVl is 8 g per liter rainwater, while only 26% of phosphorus was removed when using cation exchange resin without supported nanoscale zero-valent iron under the same condition. The adsorption capacity of R-nZVI increased up to 185 times of that of the cation exchange resin at a saturated equilibrium phosphorous concentration of 0.42 mg. L-1. Various techniques were implemented to characterize the R-nZVI and explore the mechanism of its removal of phosphate. Scanning electron microscopy （SEM） indicated that new crystal had been formed on the surface of R-nZVI. The result from inductive coupled plasma （ICP） indicated that 2.1% of nZVI was loaded on the support material. The specific surface area was increased after the load of nanoscale zero-valent iron （nZVI）, according to the measurement of BET-N2 method. The result of specific surface area analysis also proved that phosphorus was removed mainly through chemical adsorption process. X-ray photoelectron spectroscopy （XPS） analysis showed that the new product obtained from chemical reaction between phosphate and iron was ferrous phosphate.     

Advances in LID BMPs research and practice for urban runoff control in China

China is at present experiencing a very rapid urbanization process, which has brought a number of adverse impacts upon the water environment. In particular, urban runoff quantity and quality control have emerged as one of the key concerns for municipal officials. One of the strategies being considered is the use of a Low Impact Development type of Best Management Practices (LID BMPs) for urban storm water runoff quantity and quality control. In this paper, the situation surrounding urban runoff control in China is reviewed first. Then the conventional strategy and technologies for the construction and management of urban drainage systems are discussed, while exploring their inherent dilemmas. The LID BMPs are then introduced to control urban runoff in the context of urban sustainable water systems. After the comprehensive analysis of the various LID BMPs, the advances in LID BMPs research and practice for urban runoff control in China are investigated and summarized. At last, the difficulties of implementing LID BMPs in China are discussed, and a direction for the future is proposed.     

用修正RRL法计算城区径流雨水流量

随着我国城市化的发展,城市水文问题日益突出。城市排水、防洪和水污染等问题的解决,都有赖于城市降雨径流理论的发展和计算模型的改进。介绍了日本土木研究所创立的修正RRL法,并对该模型提出了改进的建议。     

基于SWAT模型的东江流域径流模拟

基于分布式水文模型SWAT以及SUFI-2 程序对东江流域进行了51 a(1960-2010 年)月径流模拟,并在此基础上讨论了东江流域水文过程的空间差异。模拟结果表明,河源站受新丰江水库影响,模拟结果不确定性较大,确定性系数R2和Nash-Sutcliffe 效率系数相对其他站点较低,龙川站、岭下站、博罗站R2和Nash-Sutcliffe 效率系数皆满足模型适用性要求。流域出口博罗站率定期R2、Nash-Sutcliffe 效率系数分别为0.83、0.83,验证期为0.84、0.84,模型模拟精度较高。东江流域径流深主要受降水空间不均影响,形成由北向南先增后减的趋势。流域下垫面差异对产流过程也有一定影响。其中土壤含水量受土壤性质、人类活动等影响,由北向南差异明显;蒸散发量受植被覆盖影响亦较为明显,北部蒸散量占降雨量的比例大于中部及南部。