Grey relational analysis on the relation between marine environmental factors and oxidation-reduction potential

The effects of marine environmental factors-temperature （T）, dissolved oxygen （DO）, salinity （S） and pH--on the oxidation-reduction potential （ORP） of natural seawater were studied in laboratory. The results show an indistinct relationship between these four factors and the ORE but they did impact the ORP. Common mathematical methods were not applicable for describing the relationship. Therefore, a grey relational analysis （GRA） method was developed. The degrees of correlation were calculated according to GILA and the values of T, pH, DO and S were 0.744, 0.710, 0.692 and 0.690, respectively. From these values, the relations of these factors to the ORP could be described and evaluated, and those of T and pH were relatively major. In general, ORP is influenced by the synergic effect of T, DO, pH and S, with no single factor having an outstanding role.

Correlations between silt density index,turbidity and oxidation-reduction potential parameters in seawater reverse osmosis desalination

The reverse osmosis method is one of the most widely used methods of seawater desalination at present.Hydrophilic and desalting membranes in reverse osmosis systems are highly susceptible to the input pollutants.Various contaminants,including suspended organic and inorganic matter,result in membrane fouling and membrane degradation.Fundamental parameters such as the turbidity,the amount of chlorine injection,and silt density index (SDI) are the most predominant parameters of fouling control in the membranes.In this study,the operation system included a water intake unit,a pretreatment system,and an RO system.The pretreatment system encompassed a clarifier,a gravity sand filter,pressurized sand filters,and a cartridge filter.The correlation between the amount of chlorine injection in terms of the oxidation-reduction potential (ORP) and the SDI value of the input water was investigated at a specified site next to the Persian Gulf.The results showed that,at certain intervals of inlet turbidity,injection of a certain amount of chlorine into the raw water has a distinct effect on the decrease of SDI.

Control for Modified University of Cape Town Process Using Oxidation-Reduction Potential in the Second Anoxic Zone

The aim of this work is to evaluate the feasibility of applying the technology of oxidation-reduction potential （ORP） control on the municipal wastewater treatment system for nitrogen and phosphorus removal. Meanwhile the relation between the optimal ORP （ ORPopt ） and influent C/N ratio was evaluated, in which the influent chemical oxygen demand （ COD ） concentration was stabilized at （290 ± 10 ） mg/L, the influent total phosphorus （TP） concentration was stabilized at （7.0 ± 0.5 ） mg/L. The results indicated that： （1） the ORP in the second anoxic zone had effect on nitrogen and phosphorus removal capability, and the average percentages of phosphorus uptake in ANO2 zone （ ηa ） increased with increasing ORP, i. e. , increasing from 12. 0% at - 143 mV to 22.0%,30.0%,37.0%, and45.0% at -123, -111, -105 and -95 mV, respectively; （2） the ORPopt as function of influent C/N ratio could be calculated by the equation： y ffi 252. 73e〈 -x/3.39） _ 131.01 ; the maximum percentage of phosphorus uptake in ANO2 as function of the ORPopt could be calculated by the equation： y ffi -0.49e（x/15.58） ＋ 1. 51. The ORPopt was the important process control parameter that must be optimized for operation of enhanced biological phosphorus removal （ EBPR ） system. Moreover, ORP sensor is very simple, and the industrial applications of this strategy is practical.

Transformation of Fertilizer-N in Rhizosphere Soils of Wheat

INTRODUCTION There is a close relationship between the transformation of fertilizer-N and the statusof nitrogen nutrition in rhizosphere soils.Previously,Harmsen and Jager(1962)made ananalysis of N and C contents in the rhizosphere soils of upland crops and found thatclose to the root zone there was an enrichment of these substances.Recently,Qin and Liu(1984;1989)investigated the distribution of nitrogen in the rhizosphere of crops after ap-

刺槐根系和根际土对7种乔灌草植物的化感潜力

刺槐(Robiniapseudoacacia)抗干旱胁迫能力、生长速率和适应性较强,是黄土丘陵区主要造林树种之一。为探究刺槐根系和根际土对该区常见乔木、灌木和草本植物的化感潜力,以刺槐根系和根际土为实验材料,采用生物测定法,设定根系和根际土浸提液质量浓度为0.5、1.0、3.0、5.0、7.0、10.0mg·mL^(-1),测定不同质量浓度浸提液对冰草(Agropyroncristatum)、侧柏(Platycladusorientalis)、刺槐、胡枝子(Lespedezabicolor)、绣线菊(Spiraea salicifolia)、油松(Pinustabuliformis)、紫花苜蓿(Medicagosativa)种子萌发和幼苗生长的影响,分析其化感作用。结果表明,刺槐根系和根际土对受体植物各指标的化感作用受到质量浓度、受体植物种类和化感物质来源,及两两之间交互作用的显著影响。1)刺槐根系和根际土浸提液促进刺槐和绣线菊的种子萌发,促进作用随浸提液质量浓度增加而加强,对绣线菊的促进作用强于刺槐;根际土对刺槐种子萌发的促进作用强于根系,对绣线菊来说则相反。刺槐根系和根际土浸提液对冰草、侧柏、胡枝子、油松、紫花苜蓿种子萌发的化感作用规律一致,呈现“低促高抑”的效应。2)刺槐根系和根际土浸提液对胡枝子、冰草、侧柏、油松、绣线菊和刺槐幼苗生长的化感作用一致,其中根系和根际土浸提液促进胡枝子幼苗生长,促进作用随浸提液质量浓度的增加先增强后减弱,且根系的促进作用强于根际土;对其他5种受体植物均表现为“低促高抑”的效应。刺槐根系和根际土浸提液对紫花苜蓿幼苗生长的化感作用不一致,根系浸提液抑制紫花苜蓿的幼苗生长,根际土浸提液对其呈现“低促高抑”的效应。该研究可为刺槐林的乔灌草复合搭配提供科学依据。

Principles of Technology for Bottling Medicinal Mineral Waters of Sairme Using the Example of Source №3a

Sairme mineral water, one of the famous mineral waters in Georgia, is renowned for its exceptional healing properties. The distinctiveness and therapeutic benefits of the naturally sourced mineral water, known as “Sairme”, stem from its rich array of microelements, notably including iron and manganese. Since 1948, the bottling of Sairme mineral water has been a prominent activity. Named after the Sairme deposit, this mineral water is packaged in various formats to cater to diverse consumer preferences. The bottling process involves transporting the mineral water from wells to the bottling plant through pipelines. Prior to bottling, the mineral water undergoes meticulous processing stages in adherence to current Georgian and international regulations. This process ensures that the concentration of trace elements in the bottled water is minimized, maintaining its purity and quality. Given the importance of preserving the microelements present in bottled mineral water, our research is dedicated to optimizing the technological process. Our objective is to safeguard the valuable microelements while ensuring the highest standards of quality and safety in the final product.

Multi-center evaluation of oxidation-reduction potential by the MiOXSYS in males with abnormal semen

According to the World Health Organization(WHO),oxidative stress(OS)is a significant contributor to male infertility.SeminalOS can be measured by a number of assays,all of which are either costly or time sensitive and/or require large semen volume andcomplex instrumentation.One less expensive alternative is to quantify the oxidation-reduction potential(ORP)with the MiOXSYS.In this international multi-center study,we assessed whether ORP levels measured by the MiOXSYS could distinguish semensamples that fall within the 2010 WHO normal reference values from those that do not.Semen samples were collected from 2092patients in 9 countries;ORP was normalized to sperm concentration(mV/10^6 sperm/ml).Only those samples with a concentration>1×10^6 sperm ml1 were in eluded.The results showed that 199 samples fell within the WHO no rmal refere nee range while theremaining 1893 samples did not meet one or more of the criteria.ORP was negatively correlated with all semen parameters(P <0.01)except volume.The area under the curve for ORP was 0.765.The ORP cut-off value(1.34 mV/10^6 sperm/ml)was able todifferentiate specimens with abnormal semen parameters with 98.1%sensitivity,40.6%specificity,94.7%positive predictivevalue(PPV)and 66.6%negative predictive value(NPV).When used as an adjunct to traditional semen analysis,ORP levels mayhelp identify altered functional status of spermatozoa caused by OS in cases of idiopathic male infertility and in male partners ofcouples sufferi ng recurre nt pregna ncy loss,and thereby directi ng these men to relevant medical therapies and lifestyle modificati ons.

Assessing high resolution oxidation-reduction potential and soluble reactive phosphorus variation across vertical sediments and water layers in Xinghu Lake:A novel laboratory approach

To understand the transfer process of soluble reactive phosphorus （SRP） on the lake sediment-water interface in a mesotrophic shallow lake in South China, the SRP concentrations and the oxidation-reduction potential （ORP） across the sediment-water interfaces were continually monitored. Sediment samples were collected from Xinghu Lake in Guangdong Province. The ORP dynamics at different layers of overlying water was similar for six experimental systems, whereas those in porewater were significantly different. The ORP in overlying water was 200-300 mV higher than those in sediments. The oxygen penetration depth ranged from 2 to 10 mm in Xiannu Lake sediments. The variation amplitudes of ORP increased with sediment depth, but the mean ORP values were all about 218 mV. The SRP concentrations in porewater maintained at a low level of about 0.049 mg/L because of high atom ratio of total iron and total manganese to total phosphorus. The SRP concentrations and variation amplitudes in porewater increased with sediment depth. The SRP in overlying water mainly originated from S RP transference of the porewater of middle and bottom sediments （3-15 cm）. The ORP variation and SRP transfer in porewater played important roles in changing SRP concentrations. A distinct SRP concentration gradient appeared in overlying water when intense exchange occurred at the sediment-water interface; therefore, it was necessary to monitor the SRP concentration profiles to accurately estimate the internal loading.

平潭沿海沙地4种典型植物叶水势特征及其影响因素

以老鼠艻、海边月见草、厚藤、卤地菊等4种沿海沙地典型植物为研究对象,采用WP4C露点水势仪测定叶水势及根际土壤水势的日变化特征,分析植物叶水势与土壤和大气因子的关系。结果显示:(1)卤地菊、老鼠艻的叶水势及根际土壤水势随气温变化表现明显的早高晚低现象。卤地菊、老鼠艻的叶水势日变幅大,水势的可调节范围广,可塑性强;随着温度升高,午间叶水势大幅下降。厚藤、海边月见草叶水势的日变幅较小,水势的可调控范围窄,可塑性低;随着温度升高,午间叶水势保持相对恒定且较高水平。(2)大气因子对植物叶水势的影响略高于土壤因子,AT和RH是影响叶水势变化的主要因素,其他环境因子随着气温的变化相继对叶水势产生影响。研究表明:卤地菊、老鼠艻对水分的调节能力较强,高温时通过低的叶水势维持水分平衡,采取冒险性水分调节,倾向于采用低水势忍耐脱水耐旱植物的水分调节策略;厚藤、海边月见草对水分的调节能力较弱,通过高叶水势延迟脱水较为保守地调节和减少水分丧失,倾向于采用高水势延迟脱水耐旱性植物的水分调节策略。

Environmental selection and evolutionary process jointly shape genomic and functional profiles of mangrove rhizosphere microbiomes

Mangrove reforestation with introduced species has been an important strategy to restore mangrove ecosystem functioning.However,how such activities affect microbially driven methane(CH4),nitrogen(N),and sulfur(S)cycling of rhizosphere microbiomes remains unclear.To understand the effect of environmental selection and the evolutionary process on microbially driven biogeochemical cycles in native and introduced mangrove rhizospheres,we analyzed key genomic and functional profiles of rhizosphere microbiomes from native and introduced mangrove species by metagenome sequencing technologies.Compared with the native mangrove(Kandelia obovata,KO),the introduced mangrove(Sonneratia apetala,SA)rhizosphere microbiome had significantly(p<0.05)higher average genome size(AGS)(5.8 vs.5.5 Mb),average 16S ribosomal RNA gene copy number(3.5 vs.3.1),relative abundances of mobile genetic elements,and functional diversity in terms of the Shannon index(7.88 vs.7.84)but lower functional potentials involved in CH4 cycling(e.g.,mcrABCDG and pmoABC),N2 fixation(nifHDK),and inorganic S cycling(dsrAB,dsrC,dsrMKJOP,soxB,sqr,and fccAB).Similar results were also observed from the recovered Proteobacterial metagenome-assembled genomes with a higher AGS and distinct functions in the introduced mangrove rhizosphere.Additionally,salinity and ammonium were identified as the main environmental drivers of functional profiles of mangrove rhizosphere microbiomes through deterministic processes.This study advances our understanding of microbially mediated biogeochemical cycling of CH_(4),N,and S in the mangrove rhizosphere and provides novel insights into the influence of environmental selection and evolutionary processes on ecosystem functions,which has important implications for future mangrove reforestation.

园艺植物根际营养学的研究——文献述评

本文综述了园艺植物根际营养学研究结果,包括根际的概念及组成,根系溢泌物的种类及效应、根际pH和根际氧化-还原电位及其作用、根际效应因子及效应组成成分以及根际研究的目的、方法、研究重点以及发展方向。

芦苇床系统净化污水的机理

人工模拟芦苇床系统净化污水的机理为：芦苇根际具有较高的氧化还原势，为好氧性微生物的活动创造了有利条件。芦苇床内根际微生物的数量与污染物去除率之间有明显的相关性。污水中的有机污染物是通过芦苇床内各种微生物的协同作用而去除；ＮＨ３－Ｎ主要是通过硝化作用和反硝化作用的连续反应而去除；总大肠菌群的去除一方面是由于原生动物的捕食作用和某些放线菌产生的拮抗作用，另一方面亦受营养、温度、ｐＨ值等因素的影响；ＳＳ和Ｏ－ＰＯ４－Ｐ的去除主要通过沉淀、过滤、吸附、固结等理化作用而实现。芦苇床内的优势细菌属为：假单胞菌属（Ｐｓｅｕｄｏｍｏｎａｓ），产碱杆菌属（Ａｌｃａｌｉｇｅｎｓ），黄杆菌属（Ｆｌａｖｏｂａｃｔｅｒｉｕｍ）。原生动物以肾形虫（Ｃｏｌｐｏｄａ）居多。

绿僵菌与植物的多重关系及其在植物保护中的应用潜力

绿僵菌是广为知晓的昆虫病原真菌,被用作生物杀虫剂防治多种农林植物害虫。近年发现它也是根际微生物群落的一员,且有证据表明它内生于一些植物的根组织中,具有促进植物生长、拮抗植物病原菌、诱导植物抗性等作用。本文着重综述绿僵菌根际作用和植物内生性研究进展,从对植物的直接作用角度,了解其田间生态适应性及与植物的互作关系,以拓展昆虫病原真菌作为植物保护剂的认识,有助于根据生态学特点制定未来的生物防治应用策略。

黄土高原旱作小麦化感表达在根际土中的时空异质性研究

采用盆栽试验基于统计学方法，对4种不同品种小麦在4个连续生长期根系表层土壤（0—20cm）化感潜势时空异质性进行了研究。结果表明：不同品种小麦之间根系土壤化感潜势差异极显著（P=0．01），随生育期变化。化感潜力的变异与品种有关，一般15cm为普通小麦耕层土壤化感潜力的转折位点。变异函数分析显示，4种小麦根系土壤化感潜势变化是独立、随机、异质性的。“碧玛1号”、“丰产3号”、“宁冬1号”、“小偃22号”变异函数理论模型分别为线形模型、球型模型、指数模型和高斯模型。其中“小偃22号”的化感背景值和化感潜力空间结构比随生育期增大，导致0～20cm表层土壤化感表达具有高度的空间异质性。4种普通小麦的化感表达均存在时空异质性，其中“宁冬1号”的表层土壤化感表达具有很好的分形特征，其空间分布格局的变异存在尺度依赖。“宁冬1号”化感潜势在表层土壤的空间分布趋于离散表达，化感潜力的有效纵向半径和有效延深半径分别为5cm和14cm。这种时空变异格局可能与根系发育特征、根系翻转运动及土壤环境有关，化感实施过程可能为熵增过程。根系表层土壤化感潜势时空异质性的研究可为监测化感作用实施，定位有效化感物质和合理利用土壤化感潜势提供理论依据，为根系分泌的化感物质可能存在迁移转化的机制奠定基础。

植物根际及土壤有机碳含量和温度对湿地甲烷产生潜力的影响

在全球气候变化的大背景下,湿地甲烷的产生和排放的研究引起广泛关注。以闽江口3种沼泽湿地土壤为研究对象,通过室内厌氧培养实验测定了距植株不同距离的湿地表层土壤的甲烷产生潜力值,研究了不同土壤有机质含量和培养温度对甲烷产生潜力的影响。结果表明:①芦苇和互花米草湿地近根际土壤甲烷产生潜力显著高于远根际土壤,而且根系越发达,相关性越大;②经过相关性分析,土壤有机碳含量和培养温度与甲烷产生潜力呈显著正相关,而且温度越高影响越显著。

杂交水稻根际供氧对土壤氧化还原电位和产量的影响

以杂交稻组合Ⅱ优7954为材料,研究根际供氧对稻田土壤的氧化还原电位及水稻产量和物质生产的影响。结果表明,与淹水处理相比,根际供氧能提高稻田土壤氧化还原电位,提高各器官的干物重,促进分蘖早发,增加有效穗数、一次枝梗数和每穗实粒数,具有显著的增产效果。

水分管理对镉轻度污染农田水稻镉积累的影响

【目的】研究镉轻度污染农田水稻适宜的水分管理模式。【方法】采用盆栽试验,分别设置水稻全生育期湿润灌溉(CK)、全生育期淹水(T1)、拔节期(T2)、孕穗期(T3)、抽穗扬花期(T4)、灌浆乳熟期(T5)、蜡熟期(T6)开始淹水7个处理,对水稻不同器官镉积累差异以及土壤氧化还原电位、根际土壤溶液水溶性镉质量分数变化进行研究。【结果】土壤氧化还原电位与水溶性Cd呈极显著正相关(p<0.01),淹水后土壤的氧化还原电位(Eh)显著降低,土壤还原性增强,淹水时间越长氧化还原电位越低,其中T1处理最低可降至-159.78mV,淹水后根际土壤溶液中水溶性Cd也迅速下降,T3处理下降最多,为75.0%。不同水分管理模式下水稻糙米含镉量均未超过食品安全国家标准规定的限量值(GB2762—2017)。与CK相比,T1处理降低稻米含镉量达76.9%,而水稻产量明显下降,减产19.2%;T6处理明显抑制镉从水稻根系向地上部分转移,增加根系镉质量占比15.2%;T6处理降低水稻茎秆的镉积累,降低茎秆镉质量占比13.0%;淹水通过抑制镉从水稻叶片向谷物的转移来降低稻米镉积累,与CK相比,T5处理叶片镉质量占比增加5.0%,T3处理谷物镉质量占比降低4.3%。【结论】综合考虑水稻产量、稻米含镉量和田间农事操作习惯,镉轻度污染稻田推荐的水分调控方式为抽穗扬花期淹水至收获前1周。

六种湿地植物根际氧化还原电位的日变化

在野外条件下,研究人工湿地植物根际氧化还原电位(ORP)随时间的变化及其与主要环境因子的关系。研究了美人蕉(Canna indica Linn.)、风车草(Cyperus flabelliformis Rottb.)、芦苇(Phragmites australis Trin.ex Steud.)、水鬼蕉(Hymenocallis littoralis(Jack.)Salisb.)、紫芋(Colocasia tonoimo Nakai.)和鸢尾(Iris tectorum Maxim.)6种植物在潜流人工湿地中的根际ORP及其日变化。6种湿地植物的根际ORP日变化曲线相似,均为双峰型,双峰值出现在11:00—14:00之间,最大值出现在14:00。各植物的根际ORP日变化基本在130—350 m V之间,以水鬼蕉的变幅最大,风车草和芦苇的变幅较小。不同植物的根际ORP有较大差异,风车草和紫芋的日平均值最大,显著高于鸢尾、美人蕉和水鬼蕉(P<0.05);芦苇显著高于鸢尾和美人蕉(P<0.05)。ORP与光照强度和气温呈正相关,尤与气温的正相关最为显著。ORP日平均值与植物生物量有显著的正相关性,尤与地下部分生物量相关性最显著。结果表明,人工湿地植物根际ORP因不同植物、一天中不同的时间有较大差异,后者与光照和气温等环境因子密切相关。

Characterization of Gleyization of Paddy Soils in the Middle Reaches of the Yangtze River

The gleyisation of representative paddy soils in the middle reaches of the Yangtze caver was characterized,taking oxidation-reduction potential(Eh),the amount of active reducing substances and the forms of iron and manganese as the parameters.The Eh value was linearly related with the logarithm of the amount of active reducing substances, which was contributed by ferrous iron by 83% on an avers.The degree of gleyization of dament horizons was graded as ungleyed,slightly gleyed,mildly gleyed and gleyed.The Eh of the four grades was>500,300-500,100-300 and<100 mV,respectively, and the corresponding amoks of active reducing substances was<1,1-7,7-30 and>30 mmol.kg(-1),respectively.The amount of ferrous iron of the four grades was<0.5,0.5-5,5-25 and > 25 mmol kg-1,respectively.The extent of gleyisation of a soil was classified as upper-gleyed, middle-gleyed and lower-gleyed, depending on whether the depth of the gley horbon was less than 30 cm,30-60 cm or more than 60 cm.

Applying real-time control to enhance the performance of nitrogen removal in CAST system

A bench-scale reactor（72 L） red with domestic sewage, was operated more than 3 months with three operation modes： traditional mode, modified mode and real-time control mode, so as to evaluate effects of the operation mode on the system performance and to develop a feasible control strategy. Results obtained from fixed-time control study indicate that the variations of the pH and oxidation-reduction potential（ORP） profiles can represent dynamic characteristics of system and the cycle sequences can be controlled and optimized by the control points on the pH and ORP profiles. A control strategy was, therefore, developed and applied to real-time control mode. Compared with traditional mode, the total nitrogen（TN） removal can be increased by approximately 16% in modified mode and a mean TN removal of 92% was achieved in real-time control mode. Moreover, approximately 12.5% aeration energy was saved in real- time control mode. The result of this study shows that the performance of nitrogen removal was enhanced in modified operation mode. Moreover, the real-time control made it possible to optimize process operation and save aeration energy.