Water quality in New Zealand rivers: current state and trends

River water quality, particularly in lowland catchments, is a matter of concern to the New Zealand public. We assessed river water quality and biological state and trends using data from more than 900 monitoring sites. Parallel state and trend analyses were carried out using all sites and a subset of lowland river sites. Median water-quality state in urban and pastoral land-cover classes was poorer than in exotic forest and natural land-cover classes, and lowland sites in the urban and pastoral classes had the poorest water quality. Nutrient and Escherichia coli concentrations increased and visual clarity and Macroinvertebrate Community Index scores decreased as proportions of catchments in high-intensity agricultural and urban land cover increased. Ten-year trends (2004–2013) indicated recent improvements in ammoniacal nitrogen, dissolved reactive phosphorus and total phosphorus in the pastoral and urban classes, possibly reflecting improved land management. In contrast, trends in nitrate-nitrogen in the exotic forest and cool-dry/pastoral classes indicated worsening conditions.     

运动目标及其可视化方法研究

在分析运动目标的内涵、基本特征及分类的基础上,探讨了运动目标的可视化表达方法。针对传统可视化技术在表达运动目标方面存在的不足,提出了一种改进型的可视化实现技术——基于显示模型技术的运动目标可视化实现方法。     

三维激光扫描技术在地质实习中的应用研究

三维激光扫描技术相对于传统的数据采集方式具有更高精度、远距离获取等优势。本文介绍了三维激光扫描技术的工作原理,并结合地质剖面分析了点云数据的采集以及获取的流程,结合生成的地质剖面模型讨论了点云数据在地质剖面分析方面的优势以及存在的问题。     

基于多视图协同的时空数据可视分析方法

针对时空数据可视分析中存在的问题,提出了由可视分析模型(VAM)和交互协同模型(ICM)组成的多视图协同可视分析模型,将可视分析过程划分为数据变换、数据分析、可视映射和可视绘制4个过程;以可视分析过程中的参数作为协同主题,利用观察者模式,实现关联视图在交互过程中的协同一致;设计了Web环境下,基于"图数协同"和"图图协同"交互模式的多视图协同可视分析架构;构建了犯罪时空数据可视分析原型系统,并利用系统分析了福州市扒窃案的时空分布规律,对涉案价值较高的扒窃案进行了犯罪模式分析。     

基于 JavaScript 的地理事件可视分析框架设计

随着互联网的飞速发展,网络环境下地理信息的可视化表达成为研究的热点。在JavaScript技术和可视分析技术研究基础上,对互联网中地理事件可视分析框架进行设计,目的是探索网络环境下,地理事件可视化的表达方式和可行性分析,搭建适合互联网的地理事件可视分析框架,为基于Web的地理信息可视分析系统的实现打下基础。     

测绘工程“四重螺旋交互上升式”硬实践体系研究

基于测绘工程专业认证的大背景和应用型高层次专门人才的需求,学生实践能力的培养被提升到了从未有过新高度,设置完善的实践教学体系迫在眉睫。为了克服"重理论、轻实践"的软人才培养理念,文中结合测绘工程专业认证标准,提出"4+5"模式培养目标,并据此构建"四重螺旋交互上升式"硬实践体系,详细阐述该体系内容构成及体系特色,为实现实践能力的本科全过程新常态培养和应用型高层次专门人才的高品质输送提供依据。     

美国海岸海洋管理的法律体系与实践

从四个阶段划分了美国海岸海洋管理的立法过程，阐述了美国海岸海洋管理法律体系的若干特征与存在的问题，并从体制、制度、政策等方面评述了海岸海洋的管理活动，最后分析了美国当前海岸海洋管理立法局长的新趋势。     

Underwater Explosion Treatment of Marine Soft Foundation

The consolidation of soft foundation is a problem that commonly appears in harbor construction engineering on muddy coast. Introduced in this paper is the experimental study on underwater explosion treatment of soft foundation, including the regulations of explosion hollow development and medium movement, the law of similarity of densification and settlement of filled stone mass by shock wave pressure and explosion energy and their construction technologies, etc. A number of projects have been completed by applying this new technique, and the technique itself has been proved practicable.     

Study on visual control system of acoustic in situ measurement technology for survey of seafloor sediment

Abstract

A new kind of visual acoustic measurement system was developed to obtain the acoustic characteristics of seabed sediment and the working state of in situ measuring equipment in real time. The control unit of the system structure is mainly made up of the underwater control unit and the deck control unit. In comparison with similar traditional systems, the system can transmit the working video image, the measured acoustic data and the waveform synchronous from the underwater control equipment to the deck control unit through the connecting cable. Apart from self-contained in situ measurement, the working modes of it include visual online real-time control. In order to guarantee the stability and measurement precision of the video control system, the process control of in situ measurement was strictly tested in the experimental tank. In 2017, sea trials of the in situ measurement system was carried out in the South China Sea. In the process, data related to measurement, including the acoustic velocity and attenuation coefficient of the seabed sediment, were obtained as well. The results from sea trials show that the control process of the visual system is intuitive, reliable and accurate, and therefore it can be popularized and applied.     

Mediterranean Marine Reserves: Fish Indices as Tests of Protection Efficiency

Abstract. The fish assemblages of a strictly protected area and of a neighbouring fished area, located off a Mediterranean urbanized coast (Carry-le-Rouet, France), were compared in order to select the most evident, constant, and easily recorded indices of the 'reserve effect'. Visual censusing was repeated simultaneously at both sites eight time a year during 3 years along four permanent transects layed on shallow rocky bottoms (9–14 m). Overall species richness was 16% higher in the reserve, but differences in average instantaneous richness were only marginally significant. The most contrasting results were shown by the occurrence frequency, abundance, and demographic structure of two types of target species. The type A target species group comprises 16 large meso- and macrocarnivores particularly threatened by spearfishing, including the common nectobenthic sparids Diplodus spp. Type B target species are represented by two small territorial fishes particularly impacted by angling: the serranid Serranus cabrilla and the terminal phase males of the labrid Coris julis . The size structure of Diplodus spp., S. cabrilla , and C.julis subpopulations strongly argues for the role of protected areas as a reservoir of large spawners. Fishing pressure is assumed to modify the social conditions of the C. julis local populations and to induce earlier sex change.