磷在"沉积物-自然生物膜-上覆水"三相体系中的迁移转化   总被引：1，自引：0，他引：1  

陆海鹰  陈建贞  李运东  方炎明  杨林章  吴永红 《湖泊科学》2014,26(4):497-504

地表水体中沉积物表面通常会附着一层自然生物膜,对上覆水-沉积物界面化学物质的迁移转化有着重要的影响.以往研究往往会忽略这一生物层面,因而,开展磷在"沉积物-自然生物膜-上覆水"三相界面之间的迁移转化研究具有重要的实际意义.以软性填料表面形成的自然生物膜模拟沉积物表层以及悬浮颗粒物表层的自然生物膜,开展磷在沉积物-自然生物膜-上覆水之间的迁移转化过程研究.结果表明:有无曝气情况下,自然生物膜界面的存在均能够显著降低上覆水中总磷、溶解态总磷、溶解态无机磷的含量,明显抑制沉积物中可交换态磷向上覆水释放.研究证明自然生物膜在水体磷的迁移转化中起着不可忽视的作用,在研究沉积物-上覆水界面之间磷的迁移转化行为时,要充分考虑自然生物膜界面的存在.  相似文献   

Physical experimental study on the formation mechanism of pockmark by aeration     

Xin Yan  Zhongxuan Chen  Feixiang Shuai  Zhenlei Wei  Yiqing Xu 《Marine Georesources & Geotechnology》2020,38(3):322-331

Abstract

As one of the common geological disasters on the seafloor, the occurrence of pockmarks often indicates the existence of submarine fluid. And the formation of the pockmarks is generally attributed to the soil carried away by the fluid. The research established physical model test and found: (1) The pockmark formed after aeration, and particle gradation changed in the center area of the pockmark where coarse particle (particle size/0.25?mm) increased obviously and fine particle (particle size ≤0.075?mm) decreased significantly; (2) Comparing the volume of the pockmark with the volume of the soil extracted by siphon, it can be found that the volume of the pockmark was much larger than the loss of soil, and the difference reached its peak when the inflation pressure was 20?kPa; (3) Comparing the cone resistance of the soil in the surface and boundary, it can be found that the resistance of the center and marginal soil was much bigger than the outside, and the cone resistance of the boundary was also improved greatly. The research considered that the formation of pockmark was not only related to the soil being carried away by the bottom current, but also the consolidation by vibration existed.  相似文献   

基于对数指数型蓄水容量曲线改进新安江模型     

贾云飞  闫志方  杜鑫 《水文》2022,42(1):16-22

原新安江模型利用一个经验函数即抛物线来考虑下垫面张力水蓄水容量空间分布不均,其数学和物理基础不明确.基于地形指数和土地利用覆被类型与包气带厚度的相关关系可以推求出张力水蓄水容量曲线,与传统概化出的曲线不同,为更好地描述流域张力水蓄水容量空间分布,在此提出用一种新的函数——对数指数函数来代替新安江模型中的抛物线以改进新安...  相似文献   

Influence of turbidity and aeration on the albedo of mountain streams          下载免费PDF全文

Alexander McMahon  R. D. Moore 《水文研究》2017,31(25):4477-4491

Stream surface albedo plays a key role in the energy balance of rivers and streams that are exposed to direct solar radiation. Most physically based analyses and models have incorporated a constant stream albedo between 0.03 and 0.10, based primarily on measurements from low‐gradient streams with low suspended sediment concentrations. However, albedo should vary with solar elevation angle, suspended sediment concentration, aeration, and fraction of direct versus diffuse radiation. The objective of this study was to quantify the dependence of albedo of mountain streams on the controlling factors and to develop a predictive model for use in physically based analysis and modelling of stream temperature, especially for future climate and land‐use scenarios. Stream surface albedo was measured at nine sites with a variety of gradients and suspended sediment characteristics in the southern Coast Mountains of British Columbia, Canada. As expected, albedo of low‐gradient, non‐white water (flatwater) streams increased with solar elevation angle, suspended sediment concentration, and proportion of diffuse to direct solar radiation, ranging between 0.025 during cloudy periods over clear water to 0.25 for turbid water at elevation angles of less than 20°. Albedo was enhanced in steep reaches or at channel steps and cascades where flow was visibly aerated, with a range of 0.09 to 0.33. In clear weather, albedo exhibited notable diurnal variability at flatwater sampling sites. For example, during late summer, surface albedo typically fluctuated between 0.08 and 0.15 on a daily basis at a flatwater site on the highly turbid, glacier‐fed Lillooet River. Multiple regression models explained approximately 60% and 40% of the variance under cross validation for flatwater and white water data subsets, respectively, with corresponding root mean square errors of approximately 0.02 and 0.06.  相似文献   

新型一体化水族箱对养鱼循环水中三氮的去除实验     

黄继国  董莉莉  高文翰  孙猛  孙锐 《吉林大学学报(地球科学版)》2011,(Z1):322-327

针对目前我国养鱼水处理器体积大、易生物堵塞、氨氮或亚硝酸盐氮积累等问题,设计了水族箱与水处理器一体化设备,采用物理过滤+生物降解+活性炭吸附工艺对养鱼水进行处理后循环利用;研究了不同工况条件下,水温、水力停留时间(HRT)、曝气量、曝气频率对养鱼水中三氮(NH4+、NO3-、NO2-)去除效果的影响。实验结果表明:水处理器污泥产量低,不易堵塞;当水温为25℃、曝气量为1.5 L/min、水力停留时间为1.5 h时,采用曝气频率0.5运行,NH4+、NO3-、NO2-皆未检出,即NH4+去除率大于97.5%,NO3-去除率大于96%,NO2-去除率大于98.7%。  相似文献   

降水入渗补给系数分析研究   总被引：4，自引：0，他引：4  

卢选伟 《地下水》2006,28(1):33-35

本文运用均衡实验站各观测系统的实验数据和资料,根据水均衡原理和"三水"转换关系,通过包气带蓄水库容有效作用分析,阐明了包气带蓄水库容和复蓄的概念,说明了包气带对土壤中水分调节作用的机理.通过对前期影响雨量系列的分析,建立了降水与入渗补给系数之间的关系,得出了降水入渗补给系数计算思路和取值公式,同时就降水入渗补给系数和地下水埋深的关系进行了探索.  相似文献   

絮凝-CO2曝气-催化氧化处理制革废水研究   总被引：5，自引：0，他引：5  

单宝田  马根之  杜春梅  胡立阁  侯海军  黄立英 《海岸工程》2001,20(3):54-59

使用新型高效的絮凝剂MF,对制革废水进行絮凝吸附、CO2曝气、催化氧化回用处理试验,确定了絮凝剂MF的最佳使用条件、催化氧化时间和氧化剂用量.结果表明,制革废水经工艺处理后,对废水中主要污染物CODCr、S2-、Cr3+、SS、色度的去除率分别达到78.9%、97.5%、95.5%、91.4%、96.5%.处理后的废水基本达到鞣铬工艺用水要求和国家<污水综合排放标准>(GB8978-1996)限定的二级标准.  相似文献   

包气带增厚条件下地下水补给规律研究   总被引：1，自引：0，他引：1  

范琦  王骥  蔺文静  陈浩 《水文地质工程地质》2006,33(3):21-24

伴随人类活动影响的不断增大,地下水位持续下降,包气带厚度增大,改变了地下水的补给条件.为阐明在巨厚包气带中水分运移规律,在河北栾城实验站进行了包气带水分运移监测试验.通过对监测数据的计算和分析,揭示了大水漫灌条件下,灌溉水在包气带中湿润峰和零通量面（ZFP）的运移和形成规律,计算了灌溉水回归补给地下水的水量,并利用达西公式进行验证.试验结果客观准确地反映了在当前人类剧烈活动影响下,包气带中水分运移规律及灌溉水补给地下水的情况,同时通过对包气带水分运移情况进行监测,取得了包气带水分运移的翔实资料和灌溉参数,对于促进农业节水灌溉有重大的现实意义.  相似文献   

包气带水研究方向浅议     

洪国华  梁会圃  王宏珍 《地下水》2005,27(5):365-366

包气带水是地球水体的重要组成部分.研究包气带水的形成及运动规律不仅对阐明地下水的形成具有重要意义,而且是实现农业节水的关键.本文在阐述包气带水特征的基础上,指出了包气带水研究方向:一是包气带中土壤水的调控研究,二是水-气二相流数值模拟研究.  相似文献   

深井曝气法处理有机废水和地下水防污染监测     

叶玲玲  陆洪清 《上海国土资源》1989,(3)

深井曝气法能处理高浓度有机废水,它具有明显的环境效益、社会效益和经济效益。本文主要介绍该项工艺流程、曝气井结构和地下水污染监测,还提出使用曝气井的几点看法。  相似文献