Real-time wastewater monitoring as tool to detect clandestine waste discharges into the sewage system

The entry of illegally discharged waste into the sewage system can cause serious damage to sewage pipes and harm the public domain. Besides industrial and communal sources, discharges from clandestine laboratories are of special forensic interest. Aim of this study is to investigate the possibility to detect clandestine discharges of possibly hazardous waste directly at the point of discharge. Tests were performed at a facility where real wastewater was pumped in a controlled way through an open sewage pipe above ground. Chloride, ammonia, pH and conductivity electrodes were investigated for their ability to detect discharges of different types of waste. Waste samples were diluted up to 50 times in a static wastewater environment and pH, conductivity and chloride electrodes were able to distinguish all waste dilutions from blank wastewater. These three electrodes were then used for dynamic tests by placing them inside flowing sewage water and discharging different types of liquid waste ten meters upstream of them. Parameters of the waste discharges like volume, time interval and speed of discharge were varied and the responses of the electrodes were collected. The dynamic tests showed that these three electrodes were able to pick up different waste discharges in a real wastewater environment. It was found that a high sampling rate of the sensors would be required to connect a certain discharge to a specific household connection. These findings highlight the possibility to locate illegal discharges, coming from a variety of sources, using the waste discharge itself.     

西沙永乐群岛岛礁海岸线变迁监测与分析

我国对南海诸岛及其附近海域拥有神圣不可侵犯的主权,珊瑚岛礁的开发、利用与保护,具有重要的战略价值。研究充分利用遥感影像宏观、快速、直观等优势,通过自动化识别与人机交互解译相结合的方法,对西沙永乐群岛岛礁岸线变迁情况进行变化监测。结果表明研究区内存在珊瑚礁岸线、基岩岸线和人工岸线三类岸线类型,以珊瑚礁岸线为主。通过对各岛礁在不同时期海岸线变迁的幅度与速度情况进行对比分析,发现珊瑚礁岸线变迁幅度最为剧烈,主要受自然因素影响,淤涨与侵蚀变迁交替作用,该类岸线处于一种不稳定的状态,其淤涨速率在不同时期不同岸段差异较大;其次为人工岸线,随着海岛的开发建设日益频繁,对土地的需求量不断增加,填海造地速度与幅度也大大增加;基岩岸线基本无变化,相对稳定。     

青岛市生态空间遥感监测与评价

从生态空间的监管需求出发,利用高分辨率卫星数据获取不同生态系统类型的分布状况,分析2012—2017年青岛市生态空间的演变格局,从水源涵养、水土保持、生物多样性维护3个方面评价青岛市生态空间的服务功能变化情况。结果表明:2012—2017年,青岛市生态空间的生态系统结构变化明显,主要表现为森林和城镇面积显著增加,草地、农田、裸地及海洋面积明显减少;水源涵养、水土保持、生物多样性维护功能的生态状况指数的增长率分别为2.63%、0.36%、2.55%,说明生态空间的生态系统服务功能得到提升,生态状况总体呈变好趋势。     

温升包络线在核电站温排水监测中的应用

采用核电站温排水遥感监测影像叠加合并方法提取温升包络线,监测核电站附近海域海表温升数据,确定核电温排水的影响范围,对海面温升面积进行计算,判断核电站温排水是否符合我国相关海洋空间管理标准。以某核电站实例表明,通过遥感监测获得的温升包络线在核电站温排水监测中具有应用价值。     

山东省省级自然保护区人类活动遥感监测与评价

基于2018年高分系列遥感影像数据,提取山东省省级自然保护区人类土地利用活动信息,探讨人类活动对山东省省级自然保护区的影响。结果表明,自然保护区人类活动总面积占保护区总面积的22.2%,人类活动影响指数介于0~0.01368。不同类型的自然保护区人类活动面积不同,主要影响因子差异明显,森林生态类保护区以农业用地为主,内陆湿地类保护区以养殖场为主。内陆湿地类保护区是受到人类干扰程度最为严重的保护区类型,野生动物类保护区受到人类影响最小。     

基于卫星影像的太湖蓝藻水华遥感强度指数和等级划分算法设计

对太湖地区近10余年来共32景Landsat TM/ETM遥感影像进行大气校正处理,获得地表反射率影像,在这些影像上采集了分布在不同片区、不同发生季节、不同集聚程度的蓝藻水华样区,提取了不同蓝藻水华的可见一近红外波段反射率数据.统计表明蓝藻水华在TM 4波段的反射率有较宽的动态范围,能定量反映蓝藻集聚程度,TM 2也是...     

环境DNA宏条形码监测水生态系统变化与健康状态

开展快速可靠的水生态监测并预测其变化趋势,对保护水生态环境具有重要的价值。近年来,环境DNA宏条形码技术(简称环境DNA技术)的快速发展弥补了传统形态学生物监测的缺陷,显著提升了水生生物群落的监测能力。与机器学习、遥感和云服务等技术结合,环境DNA技术不仅能大尺度、高频率、高灵敏度、自动化地获取生态监测信息,而且能准确地识别水生态系统的变化趋势,进而改变对水生态系统的认识与管理方式。因此,研究着重总结了环境DNA技术在水生态监测中的应用,分析了环境DNA技术与机器学习、卫星遥感等跨学科合作的潜在机遇,基于环境DNA技术简单、便捷的优势,提出了社会公民参与水环境保护的生态监测新思路。     

基于Landsat系列卫星分析1985—2015年东平湖叶绿素a浓度变化趋势

基于Landsat-5 TM数据和地面同步水质监测数据发现,近红外波段与红色波段比值与叶绿素a实测浓度存在较高相关性,并以此建立了提取水体表层叶绿素a浓度的遥感信息模型。经验证,该模型用于叶绿素a浓度反演的精度良好,平均相对误差为14.5%。将该模型应用于Landsat卫星系列数据,提取了东平湖1985-2015年每年度丰水期叶绿素a浓度信息,得到共31幅东平湖叶绿素a浓度分布图,并对其进行了时空分析。结果表明：1985-2015年,东平湖叶绿素a平均浓度范围为32.4~81.4 μg/L,空间分布上一般表现为湖周边浅水区高于湖中心深水区,且空间差异变化明显;时间序列上,东平湖叶绿素a浓度表现出一定的波动性,在1987、1988、1992年出现较高值,总体看来,在95%置信水平上秩相关系数为-0.592,浓度呈下降趋势。     

基于不同卫星降雨产品的澴水花园流域径流模拟比较研究

卫星降雨产品作为缺资料或无资料地区估算流域降雨径流的一种途径,适用性尚需大量实验研究。以澴水花园流域为研究区,综合评估了TRMM(3B42V7)、TRMM_RT(3B42V7)、PERSIANN CDR和CMORPH 4个卫星降雨产品在流域平均雨量计算与径流模拟中的精度,设置多方案与多种水文模拟情景全面检验各降雨产品的可靠性与适用性。研究表明：(1)在研究期2002~2013年,没有一个卫星降雨产品对所有精度评价指标均表现最优,PERSIANN始终表现为最差;(2)各卫星降雨产品对于不同年代和不同统计时段的精度差异明显,且一般汛期精度高于全年精度。各年代精度最高的卫星降雨产品在年与汛期尺度上与实测雨量相关系数均超过0.9;(3)各卫星降雨产品对有雨日降雨探测能力较强,但空报率较高,所有卫星降雨产品对于年最大1 d、3 d和7 d降雨估算误差较大,无法达到可利用精度;(4)采用卫星降雨产品进行径流模拟时,以相应的卫星降雨进行水文模型参数率定可获得更高的模拟精度。TRMM_RT与CMORPH日径流模拟精度较好,CMORPH月径流模拟精度较好。总体而言,CMORPH更适用于径流模拟。对于典型的3场大洪水模拟结果表明,TRMM_RT和CMORPH对洪峰与洪量（径流深）的模拟精度相对较高。     

Spatiotemporal Variability of Snow Depletion Curves Derived from SNODAS for the Conterminous United States, 2004‐2013

Assessment of water resources at a national scale is critical for understanding their vulnerability to future change in policy and climate. Representation of the spatiotemporal variability in snowmelt processes in continental‐scale hydrologic models is critical for assessment of water resource response to continued climate change. Continental‐extent hydrologic models such as the U.S. Geological Survey National Hydrologic Model (NHM) represent snowmelt processes through the application of snow depletion curves (SDCs). SDCs relate normalized snow water equivalent (SWE) to normalized snow covered area (SCA) over a snowmelt season for a given modeling unit. SDCs were derived using output from the operational Snow Data Assimilation System (SNODAS) snow model as daily 1‐km gridded SWE over the conterminous United States. Daily SNODAS output were aggregated to a predefined watershed‐scale geospatial fabric and used to also calculate SCA from October 1, 2004 to September 30, 2013. The spatiotemporal variability in SNODAS output at the watershed scale was evaluated through the spatial distribution of the median and standard deviation for the time period. Representative SDCs for each watershed‐scale modeling unit over the conterminous United States (n = 54,104) were selected using a consistent methodology and used to create categories of snowmelt based on SDC shape. The relation of SDC categories to the topographic and climatic variables allow for national‐scale categorization of snowmelt processes.