MODIS observations of water color of the largest 10 lakes in China between 2000 and 2012

Forel-Ule(FU)index of water color is an important parameter in traditional water quality investigations.We retrieved the FU index of the largest 10 lakes in China during 2000-2012 from MODerate-resolution Imaging Spectroradiometer surface reflectance product(MOD09)images.Since FU index is an optical parameter,it can be derived from optical remote sensing data by direct formulas,which is invariant with region and season.Based on validation by in situ measured reflectance data,the FU index products are reliable,with average relative error of 7.7%.FU index can be used to roughly assess water clarity:the clearer a water body is,and the bluer it is in color,the smaller its FU index is.FU index can also be used to roughly classify trophic state into three classes:oligotrophic,mesotrophic,and eutrophic.We analyzed the spatial,interannual,and seasonal variations of the FU index and its implications for water clarity and trophic state,and the findings are mostly consistent with the results from related literature.All in all,it might be a feasible way to roughly assess inland water quality by FU index in large region and over long time period.

Monitoring water color anomaly of lakes based on an integrated method using Landsat-8 OLI images

Water color is a crucial optical indicator of water quality,polluted water bodies often show water color anomalies.To comprehensively understand the occurrence of water color anomalies in inland lakes,an integrated method was designed using the hue angle based on the Forel-Ule Index(FUI)model,and other remote sensing indices,including the Turbid Water Index(TWI),Floating Algae Index(FAI),and Cyanobacteria and Macrophytes Index(CMI).Based on all available Landsat-8 OLI images from 2013 to 2020,continuous monitoring was conducted in three different lakes in the middle of the Yangtze River,China.The results demonstrated that:(1)The proposed method can accurately identify algal blooms,high sediment loads,and eutrophication from the abnormal water color areas;(2)The calculated hue angles of sediment-dominated water were significantly higher than those of algal blooms and aquatic vegetation,providing a noticeable visual discoloration of water;(3)These water color anomalies exhibited significant correlations with the water quality and environmental conditions.This study serves as an example for accurate and spatially continuous assessment of water color anomaly and supports practical information to facilitate local water environment conservation.

Study on detection of coastal water environment of China by ocean color remote sensing

Coastal water environment is essentially enhanced by ocean color which is basically decided by substances concentration in water such as chlorophyll, suspended material and yellow substance. It is very difficult, even not possible, to detect water color by expensive ship routing, because of its temporal and spatial variety of feature and scales in the very complicated dynamical system of coastal water. With the development of satellite technique in the last 20 a, space sensors can be applied to detect ocean color by measuring the spectra of water leaving radiance.It is proven that ocean color remote sensing is a powerful tool for understanding the process of oceanic biology and physics. Since the 1980s, great attention has been paid to the advanced remote sensing technique in China, especially to development of satellite programs for the coastal water environment. On 7 September 1988, China launched her first polar orbit satellite FY-1A for meteorological and oceanographic application (water color and temperature) and the second satellite FY-1B two years later. In May 1999, China launched her second generation environment satellite FY-1C with higher sensitivies, more channels and stable operation. The special ocean color satellite HY-1 is planned to be in the orbit in 2001, whose main purpose is to detect the coastal water environment of China seas. China is also developing a very advantageous sensor termed as Chinese moderate imaging spectra radiometer (CMODIS) with 91 channels, which will be a good candidate of the third generation satellite FY-3 in 2003. The technical system of ocean color remote sensing was developed by the Second Institute of Oceanography (SIO), State Oceanic Administration (SOA) in 1997. The system included data receiving, processing, distribution, calibration, validation and application units. The Hangzhou Station of SIO, SOA has the capability to receive FY-1 and AVHRR data since 1989. It was also a SeaWiFS scientific research station authorized by NASA,USA to free receive SeaWiFS data from 16 September 1997. In the recent years, the local algorithms of atmospheric correction and inversion of ocean color have been developed for FY-1C and SeaWiFS, to improve the accuracy of the measurement from satellites efficiently. The satellite data are being applied to monitor coastal water environment, such as the spatial distribution of chlorophyll, suspended material and yellow substance, red tide detection and coastal current study. The results show that the ocean color remote sensing has latent capacity in the detection of coastal water environment.In consideration of the update technique progress of ocean color remote sensing and its more important role in the detection of coastal water in the 2000s, some suggestions are set forth, which would be beneficial to the design of a cheaper but practical coastal water detection system for marine environment preservation.

Bacterial Communities Associated with An Occurrence of Colored Water in An Urban Drinking Water Distribution System

This study aimed to investigate bacterial community in an urban drinking water distribution system （DWDS） during an occurrence of colored water. Variation in the bacterial community diversity and structure was observed among the different waters, with the predominance of Proteobacteria. While Verrucomicrobia was also a major phylum group in colored water. Limnobacter was the major genus group in colored water, but Undibacterium predominated in normal tap water. The coexistence of Limnobacter as well as Sediminibacterium and Aquobocterium might contribute to the formation of colored water.

An Explanation of the Black Color of River Nyong Water’s and Associated Alluviums (Cameroon)

The River Nyong is situated in Akonolinga (central-south of Cameroon). In order to search for raw materials in ceramic use, samples of alluvium obtained from the deposits in the Nyong River clays have been studied. The results obtained show that, the samples contain important quantity of organic matter and the soil is acidic .These two parameters are necessary to understand the origin of the characteristic color of alluvium and water of the River Nyong.

The Colorful World Under Water

海底世界里,奇妙无穷;五彩缤纷的珊瑚丛里穿梭着各种形状、各种颜色的鱼,真令人神往。看起来,鱼儿在那里生活得逍遥自在,其实,它们整日里提心吊胆,时刻要提防凶猛无比的鲨鱼。你想到海底世界去看看这些鱼是如何生活的吗?那就让Bob带你一起去吧!

The statistic inversion algorithms of water constituents for the Huanghai Sea and the East China Sea

A group of statistical algorithms are proposed for the inversion of the three major components of CaseII waters inthe coastal area of the Huanghai Sea and the East China Sea. The algorithms are based on the in situ data collected inthe spring of 2003 with strict quality assurance according to NASA ocean bio-optic protocols. These algorithms arethe first ones with quantitative confidence that can be applied for the area. The average relative error of the inversedand in situ measured components' concentrations are: Chl-a about 37%, total suspended matter (TSM) about 25%,respectively. This preliminary result is quite satisfactory for CaseII waters, although some aspects in the modelneed further study. The sensitivity of the input error of 5% to remote sensing reflectance (Rrs) is also analyzed andit shows the algorithms are quite stable. The algorithms show a large difference with Tassans local SeaWiFSalgorithms for different waters, except for the Chl-a algorithm.

The black water around the Changjiang (Yangtze) Estuary in the spring of 2003

The Changjiang （Yangtze） Estuary is located in the East China Sea shelf with shallow water. Affected by the tide mixing and the runoff of the Changjiang River and the Qiantang River the turbidity is very high. Generally, the water-leaving radiance is high in the turbid water because of the large particle scattering. Based on the in-situ data and ocean color remote sensing data of SeaWiFS, it was found that there was a black water region with the normalized water-leaving radiances less than 0.5 mW/（cm2-μm2-sr）. The optical principle of the occurrence of this black water was analyzed by the inherent optical properties and the ocean color components. The results show that black water is caused by the relative low values of the suspended particle matter concentration and the back scattering ratio. In the black water region, the percentage of the phytoplankton absorption was relatively high, and the large size of the phytoplankton caused the low value of the particle backscattering ratio.

“哨兵-2”卫星影像及C2RCC算法在太湖冬春季水色分析中的应用

利用太湖2019—2022年冬春季“哨兵-2”卫星10 m分辨率的MSI影像和SNAP软件C2RCC(Case 2 Regional CoastColour)模块,以适合浑浊、富营养程度较高、光学复杂的“二类水体”的C2X-nets为模式,开展太湖叶绿素a、总悬浮物浓度、透明度等水色参数反演。结果表明:冬春季太湖各湖区叶绿素a浓度处于较低水平,但4月中旬起有明显抬升;太湖西部沿岸区、南部沿岸区和湖心区总悬浮物浓度较高,表明这些湖区易受风浪影响,造成沉积物再悬浮;太湖东部沿岸区、北部湖湾及东太湖遥感反演的水体清澈度较高,可能与这些湖区冬春季沉水植物菹草的分布有关,菹草生长对水质有较好的净化效果。总体来看,基于C2X-nets模式的C2RCC反演算法从较高分辨率卫星遥感影像中提取的水色信息,能有效反映太湖冬春季水色指标的空间分布特征,可为湖体生态状况及动态变化的长期监测评估提供有价值的参考。

Feasibility Analysis of MERIS as a Tool for Monitoring Lake Guiers (Senegal) Water Quality

ENVISAT/MERIS scenes of Lake Guiers covering the period 2003-2010 were processed for concentration retrieval of chlorophyll a (CHLa), suspended particulate matter (SPM) and colored fraction of dissolved organic matter (CDOM), i.e. the three main parameters relevant to the water quality management of the lake. Estimates in the range of 30 - 117 μg CHLa L-1 (average 62.13 μg·L-1), 0.10 - 29.0 mg SPM L-1 (average 22.01 mg·L-1), and 1.10 - 1.90 CDOM m-1 (average 1.33 m-1) were recorded, suggesting the possibility of occasional poor quality waters in some compartments of the lake. The values calculated as part of this study are consistent with literature data. On the basis of these estimates, interpretations were made as to the feasibility of applying MERIS data for synoptic environmental monitoring purposes. The data were subjected to statistical analysis, including regression analysis and significance tests. Estimates of CHLa and CDOM revealed some level of correlation, which suggests that phytoplankton biomass degradation may account for nearly 47% of the dissolved optical compounds CDOM. Notable areas of high CHLa and CDOM concentrations are found in the southern inshore zone, an environment with less water agitation. In contrast, SPM concentrations tend to increase in environments of very shallow water marked by high water turbulence and bottom mobility. However, it was not possible to fully assess the model performance and detection accuracy of the results due to lack of ground truths. Nonetheless, the results show concentrations that compared well with the insitu data from earlier studies and data reported elsewhere from other lacustrine systems. Therefore, it can be inferred from this study that MERIS data present a useful low-cost (i.e. cost effective and readily available) approach for environmental monitoring of Lake Guiers waters with excellent spatial coverage. In addition, the study highlighted the minimal effect of the so-called “bottom effect” on model predictions, despite the small depth of the lake.

影响猪肉PSE肉的形成因素及其营养调控策略研究进展

猪肉PSE肉发生率居高不下降低了我国猪肉的品质,限制了猪肉的深加工。近年来,诸多学者对影响猪肉PSE肉的形成因素进行了研究,特别是宰前补饲成为控制PSE猪肉发生率的研究热点,然而目前缺乏对最新研究成果系统深入的总结。本文系统总结了影响猪肉PSE肉发生率的遗传因素、环境因素以及其调控措施,并主要就宰前补饲维生素、氨基酸、电解质矿物元素、天然化合物对猪肉PSE肉的影响及作用机理进行了总结。降低PSE肉发生率营养添加剂的作用机制主要包括:提升血清中超氧化物歧化酶和谷胱甘肽的含量、清除氧化自由基和中断脂质过氧化作用、延缓宰后肌肉pH下降速度并提高猪肉的保水性以及作为应激状态时的主要能源物质供应来源等。此外,控制1~3 h的待宰时间、-10~30℃的运输温度、60℃下烫毛6 min,采用二氧化碳致晕及两段式冷却,可有效减少猪肉PSE肉的发生。

抗冻剂与浸渍冷冻协同处理对调理牛排冻藏期品质的影响

为阐明抗冻剂与浸渍冷冻协同处理对调理牛排冻藏品质的影响,以牛肉为原料,添加调味料或辅料,经加工制成调理牛排。调理牛排样品采用空气冻结、抗冻剂、浸渍冻结和抗冻剂与浸渍冻结联合处理进行冷冻处理。将牛排置于-30℃冰柜冻藏90 d,分别在0、30、60、90 d测定解冻损失率、汁液损失率、蒸煮损失率、质构特性、剪切力、色泽和硫代巴比妥酸反应物(thiobarbituric acid reactive substances,TBARS)值及观察牛排微观结构。结果表明:与其他处理组相比,抗冻剂与浸渍冻结联合处理组的调理牛排解冻损失率、汁液损失率、蒸煮损失率均明显降低,且TBARS值也明显低于其他处理组;此外,该处理组调理牛排的亮度值和红度值较高,组织结构中肌纤维排列整齐、最紧密。综上,采用抗冻剂与浸渍冻结联合处理调理牛排不仅能促使其组织结构紧密以保持较好的保水性,而且可保持其肉色稳定。

1990-2022年胶东调水工程调蓄水库水色时空变化数据集

胶东调水工程作为山东省骨干水网,其调蓄水库水环境状况和山东省水安全保障息息相关,利用水体颜色指标可以综合评估水库水环境状况。本文通过Landsat-5 TM、Landsat-8/9 OLI和Sentinel-2 MSI等多源卫星数据协同,利用基于FUI(Forel-Ule Index)指数的水体颜色遥感监测方法,生产了1990–2022年胶东调水工程广南水库、龙泽水库、双王城水库、峡山水库、棘洪滩水库、门楼水库、米山水库等7个调蓄水库水色时空变化数据集。数据以GeoTiff栅格格式存储,同时保存了像元FUI取值和坐标信息,便于相关的地理信息系统软件读取和分析。本数据集可以为胶东调水工程调蓄水库水环境监管、调水工程运行对调蓄水库水环境影响机制研究等提供数据支撑。

超声处理对‘烟73’干红葡萄酒颜色的影响

近年来,超声技术已在液体食品中得到了广泛应用。本文探究了一次性超声破碎(OU)和一次性超声水浴(OUB)处理后高花色苷‘烟73’干红葡萄酒颜色的变化及对酚类等物质的影响。结果表明,OU和OUB处理后葡萄酒颜色发生显著变化,颜色强度降低,色调升高,Red%值显著下降,Yellow%值和Blue%值显著上升,整体向紫红色方向演变;超声处理有效减缓了红葡萄酒颜色的褐变,显著提升了聚合色素含量,有利于葡萄酒颜色的稳定。同时,超声处理降低了钙离子、总酚和总花色苷含量,增加了铁离子和单宁含量。整体来说,OU处理对红葡萄酒颜色的影响高于OUB处理,表明超声破碎是加快葡萄酒陈酿和感官改善的有效方式。

石质文物渗水病害分级评估方法分析

针对重庆大足北山石刻不同类型渗水病害,提出了各类渗水病害分级评估方法及细分标准。基于流量—等效开度立方定律总结了不同水力梯度下滴水\流水病害分级临界条件;利用热重法研究了重庆大足紫红色砂岩和灰白色砂岩结合水含量及结合水水膜厚度,提出基于浸水面积的浸水病害分级标准;通过吸湿试验考察不同湿度环境下砂岩吸湿动力学特性,基于Fick定律计算得到不同湿度环境下砂岩水分扩散系数,明确了壁挂水病害的产生条件并提出基于接触角的壁挂水病害分级标准;借助色差仪测量了重庆大足紫红色砂岩和灰白色砂岩干燥状态和湿润状态下CIE-L^(*)a^(*)b^(*)色度坐标,提出了基于不同饱水程度(含水量)砂岩色差值ΔEn的潮湿\湿润病害分级标准。

NECDP针织物原位矿化染色工艺

针对阳离子可染涤纶(NECDP)针织物传统工艺染色排污量高、深色产品色牢度差等问题,提出采用原位矿化染色工艺对其进行后处理加工,确立了原位矿化染色技术工艺最优参数:矿化助剂XBD质量分数为1.2%、XYD质量分数为6.0%,80℃处理30 min。结果表明:与传统工艺相比,采用原位矿化染色工艺对NECDP针织物进行染色,可获得与传统工艺染样一致的颜色效果,染品耐皂洗色牢度可提高半级以上,减少染色用水约40%,降低COD_(Cr)约76%,节水、减排效果显著。

前胡药材产地干燥加工方法研究

目的比较产地不同干燥加工方法对前胡药材质量的影响,筛选其最佳产地干燥加工方法。方法分别采用传统晒干、自然阴干和电热恒温鼓风干燥、真空干燥、红外干燥和真空冷冻干燥等干燥加工方法对前胡药材进行处理,以折干率、含水量、浸出物含量、颜色色度值以及4种香豆素类成分含量为指标,采用逼近理想解排序法进行综合质量评价。结果不同干燥加工方法下,12份前胡药材样品的折干率为31.56%~40.10%,含水量为6.96%~8.58%,浸出物含量为27.56%~43.10%,红绿度值为1.80~7.50,黄蓝度值为19.90~30.20,明度值为46.90~59.90;伞形花内酯、白花前胡甲素、白花前胡乙素、白花前胡E素的含量分别为≤0.05、3.70~14.05、0.72~2.37、0.81~3.90 mg/g,总含量为5.47~19.65 mg/g;40℃电热恒温鼓风干燥下的前胡药材综合得分最高。结论40℃电热恒温鼓风干燥是前胡药材最佳的产地干燥加工方法。

水氮互作下银杏叶绿素含量与颜色特征的相关分析及估测

叶绿素含量是植物生长状况的重要指标。传统的测量叶绿素的方法费时费力,会对植物造成损伤。近年来,数字图像处理技术在估测植物叶绿素含量方向上取得了较好的进展,但针对银杏等经济林木的研究依旧偏少。以不同水氮互作条件下的2年生银杏幼苗为研究对象,使用数字扫描仪采集银杏幼苗叶片图像,利用数字图像技术构建颜色特征参数,结合相关性分析初筛出对叶绿素显著相关的颜色特征参数,并进一步基于高斯过程回归(gaussian process regression, GPR)和偏最小二乘回归(partial least squares regression, PLSR)优选建模中最为重要的颜色特征参数,建立基于银杏叶片颜色特征参数的叶绿素含量估测模型。结果表明,叶绿素含量随着施氮水平和水分处理水平的上升总体上呈现逐渐提高而后缓慢下降的趋势。基于单一颜色参数建立的单变量回归模型(R^(2)=0.01~0.72)预测精度总体上低于使用高斯过程回归(R^(2)=0.79~0.81)和偏最小二乘法(R^(2)=0.75~0.77)的模型。其中,GPR-BAT模型和PLSR-VIP模型都筛选出了对叶绿素敏感的R、G颜色特征参数;GPR模型的表现总体上优于PLSR模型,特别是在使用GPR-BAT优选颜色参数建模时表现最佳(R^(2)=0.81)。基于GPR-BAT优选颜色参数构建的GPR模型效果最佳,可准确估测银杏叶片叶绿素含量,为银杏生产的精确管理和监测银杏生长状况提供技术支撑。

不同类水的泡茶适应性研究

目的:研究不同水质对不同茶叶冲泡效果,寻找最适泡茶用水。方法:对五种水样进行水质分析,选取典型中国六大茶类的六种茶叶,分别进行不同水质冲泡,对茶汤汤色、香气和滋味感官进行评价,将水质与感官进行相关性分析。结果:离子含量等水质特性与茶汤的品质存在较为显著的相关性,纯净水和矿物质水冲泡六大茶类均较适宜,在冲泡不发酵或轻发酵茶时更能突出茶叶的鲜感、清爽感和醇爽感;而不同矿泉水在冲泡后发酵或全发酵茶时更能突出茶叶品质的醇厚感与柔和感,不同茶类具有其合适用水。研究结果可以为不同水质冲泡不同茶叶提供参考。

装配式混凝土护栏水包水多彩仿石涂料工艺研究

随着建筑行业的发展,装配式建筑因具有节能降耗、工期短、效益高等优越性而被广泛应用。本文基于装配式施工的特点,对装配式仿石混凝土护栏“水包水多彩仿石涂料”进行探讨,采用“纤维素醚—特质粘土凝胶法”制备水包水多彩仿石涂料,研究了影响基础漆和成品漆性能及稳定性的诸多因素,最终制备出综合性能优良的混凝土护栏水包水多彩仿石涂料,并在实践工程中进行了应用,验证了该技术的可靠性。