近岸海域水色异常遥感监测方法研究

水体颜色是判断水体质量的重要依据，利用遥感技术检测水色异常是进行水质评估和水体污染监测的重要技术手法。基于盐城市废黄河入海口处的GF1-WFV影像数据，利用遥感影像自身光谱特征来构建水色异常判断函数，对研究区域的水色异常进行快速提取和定位，并比较分析了基于单景影像特征和多景影像特征设置判断阈值的提取结果。研究结果表明：该方法完全基于遥感影像光谱特征，可有效提取出未知类型的水色异常信息；与基于单景影像设置的判断阈值相比，基于双景影像设置的判断阈值更合理、更适用，提取速度更快，提取范围更精确，Kappa系数为0.80;另外，采用合适窗口大小进行均值滤波处理能有效防止提取结果细碎和斑块化。     

基于欧洲航天局“哨兵-2A”卫星的太湖蓝藻遥感监测

欧洲航天局(ESA)2015年6月23日成功发射"哨兵-2A"卫星,该卫星搭载的多光谱成像仪(MSI)在可见光(VIS)至短波红外(SWIR)波长区间配置了多种光谱波段/地面分辨率组合,可以获取大范围、较短重访周期、较高空间分辨率(10 m)的遥感影像。以太湖2016年6月13日MSI数据为例,在完成大气校正的基础上,分析了太湖典型地物类型光谱特征,采用归一化植被指数(NDVI)结合叶绿素反射峰强度(ρchl)构建的综合阈值法对贡湖湾的蓝藻水华信息进行了提取实验。结果表明:"哨兵-2A"卫星MSI影像质量清晰,可精细地反映植被、蓝藻、水体等典型地物类型的光谱特征;ρchl指数对中-高蓝藻聚集区与水生植被、轻度蓝藻聚集区与混合水体具有较好的分离能力;利用综合阈值法提取贡湖湾中-高蓝藻聚集区面积为60.37 km2,主要分布在贡湖北部沿岸、湖心和南部沿岸。"藻-水"混悬体面积为79.49 km2,贡湖湾东部蓝藻水华相对较轻。     

基于微型无人机遥感数据的城市水环境信息提取初探

近年来,黑臭水体整治已经成为各级政府的重要工作内容。为更好地开展黑臭水体筛查和监管工作,提出基于多旋翼无人机搭载多光谱相机的遥感监测方案,尝试采用影像特征变换结合面向对象分类方法提取黑臭水体的遥感信息。结果表明:(1)无人机影像上地物具有更加丰富的色彩和纹理;(2)与主成分变换和纹理分析方法相比,光谱指数对典型地物具有较好的判别能力;(3)采用标准最邻近分类法提取城市水环境信息,能够获得较高分类精度。     

磨盘山水库溶解性有机质光谱特性及来源分析

结合紫外可见吸收光谱与三维荧光光谱法，利用平行因子分析方法研究哈尔滨市磨盘山水库水体中的溶解性有机质（DOM）。结果表明，水体DOM吸收系数α355平均值为（4.71±0.66）m-1，表明水库中有色溶解性有机质（CDOM）较高；水库水体DOM存在3个荧光组分，分别为类腐殖质C1（345 nm、440 nm）、类腐殖质C2（285 nm、405 nm）和类富里酸组分C3（275 nm、475 nm）；C1、C3呈现显著的正相关性，自生源指数与C1呈显著的负相关性；类腐殖质的荧光强度在深层水体中逐渐增加，且深层水体的腐殖化程度较高，较为稳定；水库中心水体中DOM的自生源特征较其他区域明显，浮游植物和细菌的有机体降解产物增加。     

基于实测光谱的烟台四十里湾水体叶绿素a遥感反演

水体叶绿素a含量是二类水体水色遥感反演的主要参数之一。通过分析烟台近海水体实测反射光谱曲线，选取了特征波段及波段组合，建立了研究区叶绿素a含量遥感反演模型。通过对比不同反演模型可知：三波段模型是烟台近海水体叶绿素a遥感反演的最优模型，决定系数为0?6608，均方根误差（RMSE）为0?59μg／L；其次是归一化荧光高度模型和反射峰面积模型，决定系数分别为0?6213和0?5589，RMSE分别为0?62μg／L和0?67μg／L。     

改进模糊综合评价和主颜色提取模型对河道黑臭独立评价

为实现水体黑度和臭度的独立评价，以四川省11个市17条黑臭或曾黑臭的河道为研究对象，利用相关性分析法、主成分分析法，提取出影响河道水体黑度和臭度的特征因子，采用改进模糊综合评价法和基于K-均值聚类的主颜色提取法搭建出黑臭程度独立评价模型。结果表明：影响河道水体发黑的特征因子是总铁、COD和DO；影响河道水体发臭的特征因子是COD、NH₃-N、TP和DO；改进模糊综合评价和主颜色提取模型对河道黑度和臭度的独立评价与实测值误差基本在一个等级以内的准确率为85.7%。河道的黑臭程度独立评价模型的确定能够实现对城市河道水质更为客观与快速的评价，为黑臭水体针对性治理与水质提升提供理论依据。     

2008-2017年苏州沿江三市主要入江支流水质变化特征

采用单因子评价法和Spearman秩相关系数评价法，对2008—2017年苏州沿江三市（张家港、常熟、太仓）主要入江支流水质变化特征进行分析。结果表明，苏州沿江三市的入江支流水质总体好转，张家港市入江支流水质明显好转，太仓市入江支流水质有所好转，常熟市入江支流水质总体保持稳定；NH₃-N、COD和BOD₅是影响入江支流水质的主要污染指标；主要污染指标优Ⅲ类比例总体呈上升趋势，但2014—2016年有所下降。2017年沿江三市入江支流水质总体处于Ⅲ类水平。     

20年间艾比湖流域植被覆盖度景观格局变化

选取艾比湖流域1990年、2001年、2011年同期（9月）3期I．and．satTM遥感影像，基于归一化植被指数NDVI，提取植被覆盖等级图，利用ArcGIS9．3和Fragstas3．3对该流域植被景观的变化进行了分析研究。结果表明：1990—2011年，该流域植被覆盖度变化明显，低植被覆盖区和较低植被覆盖区都有所减少，分别由1990年的34．05％和32．94％减少到2011年的32．8％和24．06％；较高植被覆盖区和高植被覆盖区有所增加，分别由8．49％和5．20％增长到15．13％和9．83％，但水域面积退化明显，由1990年的525．9765km2缩小至494．9876km2，减少了30．9889km2，退缩幅度达O．4％；最大斑块指数（LPI）由17．04上升到21．10，香农多样性指数（SHDI）和香农均势度指数（SHEI）分别由1．5387和0．8588增长到1．6395和0．9150。表明艾比湖流域景观格局混杂程度愈来愈高，空间异质性在逐年加强，总体空间格局向破碎化趋势发展。     

长江南京段入江支流底质多营养级微生物多样性研究

基于16S rRNA和18S rRNA高通量测序技术，研究了长江南京段21条主要入江支流不同水期底质多营养级微生物的群落结构特征，利用Shannon指数等分析了样品中微生物群落的多样性。结果表明，42个样品的细菌群落归属于285个纲水平上的OTUs (operational taxonomic units)，归属于62个门；优势菌门为变形菌门（Proteobacteria）、酸杆菌门（Acidobacteria）、绿弯菌门（Chloroflexi）等，优势菌纲为β-变形菌纲、α-变形菌纲、δ-变形菌纲等。原生动物中的优势类群为不等鞭毛类(Heterknta)、囊泡虫类（Alveolata）和绿色植物（Chloroplastida），后生动物中的优势类群为节肢动物(Arthropoda)、轮虫（Rotifera）和线虫（Nematoda）。平水期底质的细菌、原生及后生动物的多样性相对较低，入江支流的水生态系统相对不稳定，尤其是金川河、七里河等。     

淮河流域淮安段着生藻类群落结构特征分析

于2021年5月对淮安境内淮河主要干支流8个点位的水质状况和着生藻类群落结构采样调查，应用3种多样性指数模型评价区域水生态健康状况，并探究影响着生藻类多样性的因素。结果表明：采样期间淮河流域淮安市域共检出着生藻类3门23科32属（种），由硅藻门、蓝藻门和绿藻门组成，硅藻门占绝对优势；多样性指数计算结果显示，流域水生态状况良好，整体表现为清洁-轻污型水体，淮河上游水质稍差于其他水域；结合水质监测数据与卫星遥感影像分析，认为生境状况是影响着生藻类群落分布的主要因素。     

Environmental change monitoring in the arid and semi-arid regions: a case study Al-Basrah Province, Iraq

In recent years, land use/cover dynamic change has become a key subject urgently to be dealt with in the study of global environmental change. This research utilizes the integrated remote sensing and geographic information systems (GIS) in the southern part of Iraq (Basrah Province was taken as a case) to monitor, map, and quantify the environmental change using a 1:250,000 mapping scale. Remote sensing and GIS software were used to classify Landsat TM in 1990 and Landsat ETM+ in 2003 imagery into five land use and land cover (LULC) classes: vegetation land, sand land, urban area, unused land, and water bodies. Supervised classification and normalized difference buildup index, normalized difference vegetation index, normalized difference bare land index, the normalized differential water index, crust index (CI) algorithms, and change detection techniques were adopted in this research and used, respectively, to retrieve its class boundary. An accuracy assessment was performed on the 2003 LULC map to determine the reliability of the map. Finally, GIS software was used to quantify and illustrate the various LULC conversions that took place over the 13-year span of time. The results showed that the urban area, sand lands, and bare lands had increased by the rate of 1.2%, 0.8%, and 0.4% per year, with area expansion from 3,299.1, 4,119.1 km², and 3,201.9 km² in 1990 to 3,794.9, 4,557.7, and 3,351.7 km² in 2003, respectively. While the vegetation cover and water body classes were about 43.5% in 1990, the percentage decreased to about 39.6% in 2003. This study demonstrates the effectiveness of the remote sensing and GIS technologies in detecting, assessing, mapping, and monitoring the environmental changes.     

基于Sentinel-3 OLCI影像的渤海FUI水色指数遥感提取及应用

水色是水体水文学特征的基本要素之一。水色测定主要是采用福莱尔比色表(Forel-Ule Scale)将自然水体按颜色从深蓝到红棕共分为21个级别,用以观测、记录海洋和内陆水体的颜色。基于2020—2021年大辽河口、黄河口西南及秦皇岛近岸海域的现场实测数据和同步Sentinel-3 OLCI影像,验证了FUI水色指数遥感提取结果的准确性,发现当现场测量时间与卫星过境时间接近时,FUI水色指数遥感提取结果与实测结果基本一致。利用2021年1—12月Sentinel-3 OLCI影像,提取了渤海月均FUI水色指数遥感产品,发现渤海FUI水色指数的主要变化区间为5~17,整体呈现辽东湾、渤海湾及莱州湾沿岸海域高,秦皇岛海域及其他离岸海域低的空间分布特征,且存在秋冬季高、春夏季低的时间变化规律。此外,FUI水色指数对诸多海洋生态环境问题具有显著的指示功能。尝试将其应用于海洋水色异常和海水水质类别观测,均取得了较好的应用效果。由此可见,FUI水色指数遥感提取将在今后的海洋生态环境监测与评价方面发挥重要作用。     

紫外光诱导荧光分析仪结合多元线性回归算法在城市河流常规污染指标监测中的应用

为建立一种针对城市河流水体常规污染指标的快速原位监测方法,首次运用紫外光诱导荧光分析仪对扬州市60条城市河流进行水体三维荧光光谱(EEM)测量,形成了具有多样性的水质样本集合。利用峰值拾取法、相关性分析和主成分分析3种方式从三维荧光光谱中提取溶解性有机物(DOM)污染信息,结合多元线性回归算法(MLR),建立与化学需氧量(COD_Cr)、高锰酸盐指数(I_Mn)、氨氮(NH₃-N)和总磷(TP)4项常规水质污染指标相关的预测模型。研究结果表明,峰值拾取法结合相关性分析可以有效地反映水体EEM中的污染特征和状况,由此建立的4项水质指标预测模型训练集决定系数均>0.82,预测结果与国家及行业标准方法分析值之间具有较低的均方根误差,说明该预测方法具有较好的准确度和精密度,为城市广域水体的高效、原位监测提供了一种有效的解决方案。     

Determination of 16 polycyclic aromatic hydrocarbons in water using fluorinated polyaniline-based solid-phase microextraction coupled with gas chromatography

The study on the performance of a fluorinated polyaniline (PANI) as a fiber coating for solid-phase microextraction (SPME) had been reported and 16 polycyclic aromatic hydrocarbons (PAHs) were selected to evaluate the performance of this fiber. Various parameters including sample volume, extraction temperature, time of desorption and extraction, pH and ionic strength were investigated intensively. A direct comparison between PANI-SPME fiber and commercial fiber was conducted. The results showed that the PANI-SPME coating had high affinity towards target compounds and the proposed method was successfully applied for the detection of real samples: rainfall and Taihu Lake water collected from Southern China. The whole PANI-SPME-GC method offers acceptable accuracy, precision and sensitivity and low detection limits, which is applicable to monitor trace levels of PAHs in real water bodies.     

汉江下游干支流浮游植物群落特征及其对水质的指示评价

浮游植物群落的动态变化可以全面、真实地反映水质的优劣,有利于了解水体污染状况的发展趋势.为及时掌握汉江下游水质变化,基于2019年3—12月汉江下游干流及主要支流浮游植物和水体理化指标监测数据,分析了浮游植物群落结构特征,并通过冗余分析研究了影响浮游植物群落结构的主要环境因子,同时运用浮游植物群落特征对汉江下游水质进行...     

Spatial and seasonal characteristics of river water chemistry in the Taizi River in Northeast China

Anthropogenic activities have led to water quality deterioration in many parts of the world, especially in Northeast China. The current work investigated the spatiotemporal variations of water quality in the Taizi River by multivariate statistical analysis of data from the 67 sampling sites in the mainstream and major tributaries of the river during dry and rainy seasons. One-way analysis of variance indicated that the 20 measured variables (except pH, 5-day biological oxygen demand, permanganate index, and chloride, orthophosphate, and total phosphorus concentrations) showed significant seasonal (p?≤?0.05) and spatial (p?<?0.05) variations among the mainstream and major tributaries of the river. Hierarchical cluster analysis of data from the different seasons classified the mainstream and tributaries of the river into three clusters, namely, less, moderately, and highly polluted clusters. Factor analysis extracted five factors from data in the different seasons, which accounted for the high percentage of the total variance and reflected the integrated characteristics of water chemistry, organic pollution, phosphorous pollution, denitrification effect, and nitrogen pollution. The results indicate that river pollution in Northeast China was mainly from natural and/or anthropogenic sources, e.g., rainfall, domestic wastewater, agricultural runoff, and industrial discharge.     

HPLC-FLD测定水中联苯胺的方法研究

探讨了利用液相色谱分离,荧光检测器测定地表水中联苯胺的可行性。前处理方法对比验证了液液萃取法和固相萃取法。水样在碱性条件下(pH=11~12)进行提取,当提取体积为1.0 L时,液液萃取液相色谱荧光法检测,方法检出限为1.4 ng/L,定量下限为5.5 ng/L;固相萃取液相色谱荧光法检测,方法检出限为0.9 ng/L,定量下限为3.6 ng/L。分别对地表水、生活废水、工业废水3种不同水体进行基体加标试验,加标浓度为10.0、40.0、80.0 ng/L。结果显示,对于3种不同基体和不同加标浓度的水样,两种方法均有较好的准确性和重现性,方法回收率为80%~120%,相对标准偏差均小于20%,满足《地表水环境质量标准》(GB 3838—2002)中对联苯胺的监测需求。     

西安市景观水体营养状态调查及浮游藻类多样性研究

对西安市城区景观水体浮游藻类状况及生物多样性进行了研究。结果表明,7个景观水体中有5个水体的水质未达到Ⅴ类水质标准,主要超标项目为pH值和TN;7个水体的ρ(N)/ρ(P)为16.6~43.6,磷为限制性因子;其中2个水体富营养化严重,DO含量低,水质达不到要求,其优势藻种为蓝藻门,含量占浮游藻类总数的64.3%~93.4%;而水质较好的贫营养水体优势种为黄藻门,含量占到浮游藻类总数的54.3%;通过6种生物多样性指数与景观水体营养状态的拟合,发现MeNaughton's多样性指数适合城区景观水体的富营养化评价。     

Using Landsat image time series to study a small water body in Northern Spain

Ramsar Convention and EU Water Framework Directive are two international agreements focused on the conservation and achievement of good ecological and chemical status of wetlands. Wetlands are important ecosystems holding many plant and animal communities. Their environmental status can be characterised by the quality of their water bodies. Water quality can be assessed from biophysical parameters (such as Chlorophyll-a concentration ([Chla]), water surface temperature and transparency) in the deeper or lacustrine zone, or from bioindicators (as submerged aquatic vegetation) in the shallow or palustrine zone. This paper proves the use of Landsat time series to measure the evolution of water quality parameters and the environmental dynamics of a small water body (6.57 ha) in a Ramsar wetland (Arreo Lake in the North of Spain). Our results show that Landsat TM images can be used to describe periodic behaviours such as the water surface temperature or the phenologic state of the submerged vegetation (through normalized difference vegetation index, NDVI) and thus detect anomalous events. We also show how [Chla] and transparency can be measured in the lacustrine zone using Landsat TM images and an algorithm adjusted for mesotrophic Spanish lakes, and the resulting values vary in time in accordance with field measurements (although these were not synchronous with the images). The availability of this algorithm also highlights anomalies in the field data series that are found to be related with the concentration of suspended matter. All this potential of Landsat imagery to monitor small water bodies in wetlands can be used for hindcasting of past evolution of these wetlands (dating back to 1970s) and will be also useful in the future thanks to the Landsat continuity mission and the Operational Land Imager.