Arsenic and major cation hydrogeochemistry of the Central Victorian （Australia） surface waters

This paper reports on the major cations（Ca, Mg, Na and K） and arsenic（As） compositions of surface waters collected from major creeks, rivers and lakes in Central Victoria （Australia）. The surface waters were found to be neutral to alkaline （pH 6.7-9.4）, oxidised （average redox potential （Eh） about 130 mV） and showed variable concentrations of dissolved ions （EC, about 51-4386 /μS/cm）. The concen- trations of dissolved major cations in surface waters were found to be in the order of Na〉〉Mg〉Ca〉K and in soils the contents of metals followed an order of abundance as： Ca〉Mg〉〉K〉Na. While Na was the least abundant in soils, it registered the highest dissolved cation in surface waters. Of the four major cations, the average concentration ofNa（98.7 mg/L） was attributed to the weathering of feldspars and atmospheric input. Relatively highly dissolved concentrations of Na and Mg compared with the world average values of rivers reflected the weathering of rock and soil minerals within the catchments. The As soil level is naturally high（linked to lithology） as reflected by high background soil values and mining operations are also considered to be a contributory factor. Under relatively alkaline-oxidative conditions low mobility of dissolved As （average about 7.9 μg/L） was observed in most of the surface waters with a few higher values（〉15 μg/L） around a sewage disposal site and mine railings. Arsenic in soils is slowly released into water under alkaline and/or lower Eh conditions. The efficient sink of Fe, AI and Mn oxides acts as a barrier against the As release under near neutral-oxidising conditions. High As content （average about 28.3 mg/kg） in soils was found to be associated with Fe-hydroxides as revealed by XRD and SEM analysis. The dissolved As concentration was found to be below the recommended maximum levels for recreational water in all surface waters（lakes and rivers） in the study area. Catchment lithology exerted the fundamental control on surface water chemistry. Sites impacted by mining waste dumps showed a decline in water quality.

Response of antioxidase in viscera of Pagrosuma Major larvae to water soluble fraction of hydrocarbons in No.0 diesel oil

Pagrosomus major larvae were exposed to the water soluble fraction of hydrocarbon in No.0 diesel oil (corresponding to No.2 fuel oil) at concentrations of 0, 0 17, 1.22 and 8 82 mg/L for up to 15 days. Larvae were sampled on days 9 and l5 of the experiment. Supernatants of viscera tissue extractions were assayed for biochemical response in terms of oxidative stress superoxide dismutase(SOD), activity of selenium dependant glutathione peroxidase(Se GPx) and catalase(Ca), and the concentration of reduced glutathione(GSH). On day 9 of exposure, statistically significant dose related increases in Se GPx and SOD activity, and GSH concentration were observed in all cases except for Se GPx activity under the highest dosage of hydrocarbon. However, on day l5 of exposure, a similar dose related response was only observed for Se GPx activity. GSH concentration decreased and SOD activity showed no statistical difference as compared to controls. However, a significant decrease in compared to day 9 Se GPx activity and GSH concentration, in contrast to increase SOD activity at day 15 as indicates an accelerated accumulation of H 2O 2 and potential oxidative damage under long term exposure of larvae to hydrocarbons. No statistical changes were observed in Ca activity throughout the experiment, possibly owing to the high efficiency of Se GPx. A recovery experiment was performed on indicating that the response of antioxidants measured tending to return to their control levels. These results prove the function of the antioxidant defense system of the larvae to the water soluble fraction of hydrocarbons in No.0 diesel oil.

Geochemical constraints on seasonal recharge of water and major dissolved solutes in the Huangshui River,China

The Huangshui River,an important tributary in the upper reaches of the Yellow River,has been regarded as a mother river which gestates Qinghai civilization in China.This paper presents the results of hydrogen and oxygen isotopic and water chemical analyses for the summer and winter Huangshui River water to study its seasonal recharge and major dissolved solutes.Characteristics of hydrogen and oxygen isotopes suggest that precipitation in the Qilian Mountains is the original recharge of the Huangshui River.However,in winter,the basic flow of the Huangshui River only depends on spring recharge and spring water originates from melt and infiltration of bottom layer glaciers.In summer,besides spring water,much rainfall directly recharges the Huangshui River,thus making its flux increase greatly.Water chemistry shows that the processes affecting dissolved solutes in the Huangshui River are also different between summer and winter.In summer,major ions in the river water are dominantly derived from carbonate and evaporate dissolution and anthropogenic inputs.In winter,carbonate dissolution decreases greatly while anthropogenic inputs play a much more important role for dissolved solutes in the river.Hence,further measures should be taken to lay stress on the winter Huangshui River water in order to protect the environment of the Huangshui River and reduce effects of dissolved solutes on,or prevent their pollution toward the upper Yellow River.Moreover,some measures also need to be introduced to prevent the possibility of water eutrophication caused by agricultural activities or stock raising in summer.

Convolutional Neural Network-Based Identity Recognition Using ECG atDifferent Water Temperatures During Bathing

This study proposes a convolutional neural network(CNN)-based identity recognition scheme using electrocardiogram(ECG)at different water temperatures(WTs)during bathing,aiming to explore the impact of ECG length on the recognition rate.ECG data was collected using non-contact electrodes at five different WTs during bathing.Ten young student subjects(seven men and three women)participated in data collection.Three ECG recordings were collected at each preset bathtub WT for each subject.Each recording is 18 min long,with a sampling rate of 200 Hz.In total,150 ECG recordings and 150 WT recordings were collected.The R peaks were detected based on the processed ECG(baseline wandering eliminated,50-Hz hum removed,ECG smoothing and ECG normalization)and the QRS complex waves were segmented.These segmented waves were then transformed into binary images,which served as the datasets.For each subject,the training,validation,and test data were taken from the first,second,and third ECG recordings,respectively.The number of training and validation images was 84297 and 83734,respectively.In the test stage,the preliminary classification results were obtained using the trained CNN model,and the finer classification results were determined using the majority vote method based on the preliminary results.The validation rate was 98.71%.The recognition rates were 95.00%and 98.00%when the number of test heartbeats was 7 and 17,respectively,for each subject.

Hydrogeochemical Variations of Groundwater of the Northern Jabal Hafit in Eastern Part of Abu Dhabi Emirate, United Arab Emirates (UAE)

This study is aimed to assess and evaluate the suitability of groundwater of the area located to the south-east of Al-Ain area in the UAE using hydrogeochemcical approach. The chemical analyses of groundwater samples collected from the study area showed that the groundwater salinity is high which resulted from heavy groundwater pumping. High chloride concentrations in groundwater of Mubazarah and Neima might be attributed to the entrapped saline water within the limestone sequence of Jabal Hafit, or it can be the agricultural activities as it clear from the positive relationship between Cl- and Br-. High sulphate concentrations in groundwater might be related to the presence of gypsum and anhydrite within the limestone sequence of Jabal Hafit. The anionic and cationic compositions of groundwater indicate that the chloride and sodium ions are the dominant and presence of bicarbonate and sulphate may reflect the mixing of such water by the recent freshwater through the existing structural lineaments within the study area. The hydrochemical parameters indicate a relative increase in the concentration of calcium, magnesium and sulphate ions and this could reflect the influence of carbonates and evaporite sediments.

Effect of Polyacrylamide Application on Water and Nutrient Movements in Soils

An understanding of nutrient movement in soil is important for developing management strategies to minimize nutrient leaching and surface movement, thus improving nutrient uptake by plants, maintaining a sustainable soil system, and even protecting groundwater quality. Polyacrylamide (PAM) is known as one of soil conditioner that functions to stabilize soil structure, increase infiltration, and reduce surface runoff. This study assesses the effects of PAM on the vertical movement of soil-water and major/minor nutrients (NO3-N, NH3-N, T-N, PO4-P, T-P, K, Ca, Mg, and Fe) in soils. Saturated hydraulic conductivity (Ksat) increases with increasing PAM concen- trations up to 10 mg·L-1 for sand and 20 mg·L-1 for a mixture of sand and clay. Decreases in the loss of soluble nutrients, particularly NH3-N, PO4-P and T-P, are observed as PAM concentrations increase. In contrast, PAM concentration has no effect on nitrate and minor nutrient levels. These results indicate that the application of PAM may be a viable method for protecting water bodies from excessive nutrients and improving nutrient availability for plants.

SPECTRUM CHARACTERISTICS OF MAJOR IONCONCENTRATIONS AT WUHAN SECTOIN OF THECHANGJIANG RIVER

ABSTRACT: Spectrum analyses of water quality time series have been carried out for five hydrometric stations including Wuhan hydrometric station of the Changjiang( Yangtze) River, etc. The fluctuations of Ca2 +, Mg2+ and HCO3-concentrations in river water under different physical geography conditions have about two-year cycle which is corresponding to hydrometeorological quasi-biannual-oscillation(QBO). Na + Cl- SO2-4 have about two-year cycle in the area lightly affected by human activities while two-year cycle doesn’t exist in the area heavily affected by human activities. All the fluctuations of major ions have about three-month cycle. The river discharge fluctuation accounts for 43. 9% , 45.1%, 54.3%, 33.9%, 30.3% and 42. 7% of the variance of Ca2 +, Mg2+ HC03-, Na+ Cl-, SO2-4, respectively, at Wuhan from 1962 to 1985. According to the spectrum characteristic of major ions, the duration of the time series has to be at least 13 years for trend analysis of monthly water quality data.

Major Elements in Lake Muhazi,Rwanda,East Africa

The aim of this study undertaken at Lake Muhazi in Rwanda was to determine and analyze the major elements present in water. The presence of many major elements （Al, As, Ba, C, Ca, Cu, Fe, H^＋, K, Mg, Mn, N, P, S, Si, and Zn） was determined by spectroscopic technique. The concentrations of the elements were measured in water samples taken from three different locations of the lake from May to August 2008. The lake is polluted by water flow from mountain sides surrounding the lake. Other causes of pollution could be the use of agrochemicals in the sugar land, which surrounds the lake, and human activities near the lake. Finally, we proposed the strategies that can be applied in order to ensure good conservation of the environment and to prevent augmentation of heavy materials into the lake.

Hydrogeochemistry of karst underground waters at shallow depth in Guiyang City, Guizhou Province

The aim of this study is to shed light on the hydrogeochemical characteristics of karst underground waters at shallow depth in Guiyang City, Guizhou Province with an emphasis on the geochemistry of major elements. Guiyang City bears abundant underground waters and it is also an important representative of the karst areas throughout the world. Ca+{2+} and Mg+{2+} are the dominant cations, accounting for 81%-{99.7%} of the total, and HCO+--3 and SO+{2-}-4 are the dominant anions. Weathering of limestones and dolostones is the most important factor controlling the hydrogeochemistry of underground waters, and weathering of sulfate and evaporite rocks is less important. Moreover, the precipitation and human activities also have a definite influence on the hydrogeochemistry of underground waters in the region studied.

基于OBE理念的农业高校水利类专业人才培养模式改革研究

水利专业属于传统工科专业,各高校在长期教学实践中形成了“以教为中心”的人才培养模式,已经不能满足当代水利行业工程建设与管理的人才要求。自我国加入华盛顿协议以来,我国高校工程教育进入了全新的发展阶段。农业高校水利类专业需兼顾水利工程专业与服务农业特色两方面的要求,在我国智慧水利与智慧农业建设全面开展的大背景下,亟需对传统人才培养方案进行改革。该文从培养目标、课程体系、课程内容及教学方法等方面探讨了基于成果导向教育(OBE)理念的人才培养模式教学改革方案,可为农业类高校水利专业人才培养模式改革提供借鉴。

Analysis of Micro Organic Compound Pollution in Major City River Reaches of the Main Stem of the Changjiang River

It has become general for surface waters being polluted by micro organic compounds. In order to know the current pollution situation and the properties of micro organic compounds in the Changjiang River, a test was performed on micro organic compounds in the water, bottom material and fish bodies which were sampled from major city river reaches of the Changjiang River. Based on the test result, researchers described and analyzed the sorts, concentration level and distribution features of micro organic compounds. A comprehensive evaluation was conducted by adopting the method of MEG (Multimedia Environmental Goals). The study indicated that ① the water body of major city river reaches of the Changjiang River has been generally polluted. In the test, totally 12 types with 308 kinds of organic compounds were detected. The main pollutants were paraffins, PAHs and lipids; and ② micro organic pollutant content in fish bodies was generally higher than that in bottom material which is in turn higher than that in water; and ③ pollution is relatively severe in the river reaches of mid-to-large comprehensive industrial cities with fairly great TAS (Total Ambient Severity) of public health and ecological system.

工业互联技术在校园供水系统中的应用探讨——以南京中医药大学二次供水泵站智慧化改造项目为例

高校作为社会用水大户,由于用水类型复杂、部分学校供水设施落后老化、水系统智慧化管理手段缺失或应用效果不达标等因素,导致校园供水系统存在运行安全性不高、水质水压无保证、管道漏损率偏高、管理效率低下等问题。南京中医药大学运用以工业互联技术为核心的一系列先进技术,改造建成智慧供水标准化泵站。通过智联供水设备改造,环境保障改造,蓄水池水质保障改造,压力调节系统改造等,并通过平台化管理提高运维管理效率,实现了良好的改造效益。

中高职一体化课程体系构建研究与实践——以水生态修复技术专业为例

中高职一体化培养是建立现代职业教育体系的重要举措之一,中高职衔接的核心是一体化课程体系的构建。通过分析一体化课程体系内涵及构建途径,以水生态修复技术专业为例,探索构建中高职一体化课程体系,以实现中高职一体化人才培养的有效衔接,提高技术技能人才培养质量。

藏东南雅江流域冰-岩崩灾害链研究进展

全球气候变暖导致冰-岩崩及其灾害链成为研究热点,然而由于此类灾害多发于高寒地区,监测和模拟手段不足,研究困难且成果有限。我国西藏东南部雅鲁藏布江流域是冰-岩崩灾害高发区,也是水电建设重要区域,其冰/岩体稳定性对水利工程建设、运营及人民安全构成严重威胁。在全面梳理国内外研究现状的基础上,汇编了雅江流域近70年来有相关记载的冰-岩崩事件;通过深入调查分析,对冰-岩崩灾害进行了重新界定,并探究了该地区冰-岩崩灾害的时空分布规律;进一步,结合雅江流域独特的地理特征,初步揭示了冰-岩崩的形成机制,并将冰-岩崩灾害划分为冰-岩崩泥石流灾害、冰-岩崩堵江溃坝型灾害、冰-岩崩冰湖溃决型灾害和冰-岩崩库坝失效型灾害四种。在此基础上,基于CiteSpace可视化分析软件和WoS核心合集数据库,定量分析了最近25年(1999—2023年)国内外对于冰-岩崩灾害的研究现状,指出了不同时间段的研究热点和发展趋势。上述成果为雅江流域冰-岩崩灾害的深入研究及重大水利工程防灾减灾提供参考价植。

基于主量元素地球化学的岩屑层位源解析

近年来,岩屑录井在“华北型”煤田底板灰岩层注浆加固工程中发挥了重要作用。然而,现有的岩屑录井仅停留在颜色、颗粒大小及形貌特征等物理指标的识别上,难以精准判层,钻孔设计“顺层率”难以保障,制约着底板灰岩水害区域治理效果。基于石炭纪太原组薄层灰岩及其碎屑岩夹层的元素地球化学差异特点,选取淮北煤田桃园煤矿为研究区,对太原组上段薄层灰岩L_(1)灰~L_(4)灰地层(注浆治理目的层为L_(3)灰)垂直钻孔岩心进行取样,利用X射线荧光光谱仪(XRF)定量测定了薄层灰岩及其夹层的主量元素背景值,通过聚类分析、因子分析等数理统计手段建立薄层灰岩主量元素地球化学识别模式;同时对地面定向钻水平分支孔岩屑同样开展主量元素测试,并基于已建立的地球化学识别模式进行岩屑层位源解析以及识别模式验证。结果显示:高CaO丰度、烧失量(LOI)可以作为注浆加固改造目的层L_(3)灰的特征指标,MgO(0.5%±)、MnO(0.03%±)、P_(2)O_(5)(0.08%±)丰度可作为注浆目的层上覆标志层J3的识别指标;聚类分析识别模式可有效区分太原组一灰~三灰(L_(1)灰~L_(3)灰);以元素因子得分建立的识别模式可以将太原组碎屑岩夹层与薄层灰岩进行有效区分;以岩样地球化学背景值运行判别模型得到的Fisher判别方程对注浆目的层L_(3)灰岩屑来源解析的准确率为100%。基于上述认识,论证了以确保设计“顺层率”为目标的水平分支孔岩屑地球化学源解析方法应用之可行性,进而提出了一种地面定向钻“顺层率”控制技术方案。本研究基于元素地球化学理论,对地面定向钻岩屑携带的特征地球化学信息进行了目的层层位辨识,在现场快速定量测试技术手段的支持下,可为解决华北型煤田底板灰岩水害区域注浆改造顺层难题提供了新的思路。

水利建设投资对经济增长影响效应研究

水利基础设施建设作为扩大内需的重要领域,具有吸纳投资大、产业链条长、形成工程量快、促进就业能力强等特点,承载着稳投资、稳增长的重任。10年来,全国水利建设完成投资达到7.5万亿元,先后实施了172项、150项重大水利工程,为稳定经济大盘、推动江河治理、增进民生福祉提供了重要支撑。在新阶段新形势的要求下,跟踪水利建设投资数据,建立常态化的研究机制,科学研判水利建设投资对经济增长的影响尤为重要,不仅有助于更好发挥水利建设经济成效,而且也为促进经济回稳向上提供水利支撑。

“绿水青山就是金山银山”理论与实践指导下的《高等环境化学》课程建设

“绿水青山就是金山银山”是习近平总书记的重要环保理论,阐明了环境保护、经济发展和民生工程之间相辅相成的关系。本文根据2012年以来对于环境的投入、全国水质国控断面及长江与黄河重要流域Ⅰ-Ⅲ类和Ⅴ类水占比、森林覆盖率、生物物种数量、空气质量等翔实的数据分析了我国环境总体向好的趋势,进一步以国内生产总值、人均寿命等数据验证了“绿水青山就是金山银山”理论。研究生环境专业学生是未来环境保护和建设的主力军,在其《高等环境化学》课程教学中,融入“绿水青山就是金山银山”理论既能提升学生的环保意识、社会责任感和综合素质,更能加深学生的爱国爱家情怀,为实现“中国梦”培养创新型高素质人才奠定基础。

CDIO模式下一流专业课程实践教学改革探究——以给水排水管网系统为例

针对给排水科学与工程一流专业的人才培养目标,通过剖析给水排水管网系统课程教学现状和存在的问题,提出基于CDIO模式的创新实践教学体系。将项目驱动、“做中学”等教学方法引入给水排水管网系统课程实践教学,探索实践与理论深度有机融合的途径,提升学生对现代化管网系统的设计、运行及管理意识,为培养创新型人才提供思路和借鉴。

OBE模式下水利专业大学生创新创业能力培养研究

在水利工程领域,由于技术、环境和政策的不断变化,市场竞争日趋激烈,社会对水利专业大学生的要求越来越高,不仅要求他们具备扎实的专业知识,还需要他们具备较高的创新创业能力。文章分析OBE模式与创新创业教育的内在联系,提出OBE模式与创新创业教育结合的现实意义,阐述高校水利专业大学生创新创业能力的培养现状,并对OBE模式下水利专业大学生创新创业能力的培养路径进行探讨,旨在培养更具竞争力的水利工程人才。

改性粘土对对虾养殖池塘主要生源要素的调控作用

高强度养殖活动显著改变了主要生源要素的分布特征与循环过程,导致养殖水体呈现严重富营养化状态、有害藻华频发,既限制了养殖业的健康发展,又对周围海洋生态环境造成了负面影响。近年来,养殖水体水质调控成为研究热点,基于2023年5~9月份对莱州湾凡纳滨对虾精养池塘水体主要生源要素的现场观测与对比体系研究,揭示了改性粘土对主要生源要素分布特征的影响,结合培养实验,探究了改性粘土对主要生源要素循环的调控作用。结果表明,对虾养殖池塘水体中主要生源要素(碳、氮和磷)含量整体呈现波动上升的变化趋势。喷洒改性粘土24 h后可以迅速降低水体溶解无机氮(dissolved inorganic nitrogen,DIN)和溶解无机磷(dissolved inorganic phosphorus,DIP)含量,去除率都达90%以上,且在养殖过程中实验池水体总有机碳(total organic carbon,TOC)、总氮(total nitrogen,TN)和总磷(total phosphorus,TP)含量均值都低于对照池。培养实验结果发现,改性粘土能够显著降低TOC矿化速率与DIN、DIP再生速率,有效促进了有机碳的埋藏,延缓了营养盐的再生与释放。综上,改性粘土可以降低水体中有机碳和营养盐含量,起到有效调控养殖水体水质的作用,并可促进有机碳的埋藏封存,在海洋碳埋藏增汇方面展现出良好的应用前景。