地理国情监测中水域范围与水域要素套合问题分析     

卢其垡  孙进冬  张刘芹 《测绘与空间地理信息》2021,44(6):145-147

针对地理国情监测中地表覆盖水域范围与地理国情水域要素套合时存在的诸多问题,本文提出了利用DEM水文分析法和ArcGIS空间关系排查法进行优化处理的方法.实践证明,利用该方法能解决两类数据时空不一致以及其他情况引起的套合问题,使得在全国尺度上的地理国情监测水域数据成果更加准确、客观、可靠,为提高地理国情监测成果质量提供了有力保障.  相似文献   

基于高通量测序的象山港水域细菌多样性的研究     

刘岩  李志恩  袁一鸣  张真  钱鹏宇  叶欢  刘松怡  王泽  韩姣姣  周君  苏秀榕 《海洋与湖沼》2022,53(3):645-653

象山港位于浙江省宁波市东南部沿海,属于半封闭式海湾,是以海水养殖区和海洋牧场示范区为主的重要多功能水域,近年来生态环境问题日益突出。为研究象山港海域在早春低水温环境中细菌的多样性,通过高通量测序方法对3月份的象山港水域进行检测。沿象山港南部海湾随机选取6个取样点(G04,G06,G08,G09,G011,G012),共检出836属和2 166种细菌,隶属33个门、91纲、186目和352科。其中优势细菌类群主要包括变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、放线菌门(Actinobacteria)、厚壁菌门(Firmicutes)和蓝细菌门(Cyanobacteria)。变形菌门在G04中占比最高(91.45%),拟杆菌门在G09中占比最高(18.05%);而放线菌门在G12中占比最高(7.95%)。在经度较高且离海岸较远的水域,细菌丰富度也越高;同时随着取样位点纬度的增加,γ-变形菌丰度逐步增高,其中在G04中最高(72.76%),在G12中最低(29.11%)。各取样点的细菌分离培养结果也表明弧菌属丰度较高,且主要集中在G04中。利用高通量测序方法揭示了象山港早春全水域的细菌结构组成框架图,可为象山港的水产养殖和可持续发展提供参考依据。  相似文献   

工程海域波浪特征分析方法比较     

王科华  任赵飞  周智鹏  李伟仪 《海洋工程》2022,40(3):149-158

通过选取两个典型海外工程项目案例,分别采用波浪特征参数法和波浪谱法对工程海域波浪条件进行分析,并比较这两种方法在作业波浪条件、波浪特征认知程度上的差异,以及对海港水域平面布置产生的影响。对于波浪能量在频域及方向上存在多峰谱情况的海域,基于全谱的波浪特征参数系列数据有可能出现以下两种情况:1)主峰波向掩盖次峰波向;2)主峰波向错配次峰周期。对于上述两种情况,若仅采用波浪特征参数法对工程海域作业波浪条件进行分析,并指导海港水域平面布置,则极可能忽略或误判个别敏感波向、关键频域段的部分波浪能量,从而误导设计,为后续项目运营埋下隐患。对于以上情形,宜采用波浪谱法深入分析工程海域波浪能量在整个频域及各个方向上的详细分布及构成,并对关键波向、关键频域段的波浪能量进行量化,评估其对海港水域平面布置的影响,从而最大程度地避免由于波浪输入条件误判带来的风险。  相似文献   

1972～2011年期间艾比湖面积变化研究   总被引：2，自引：0，他引：2  

李 磊李艳红  陈成贺日等 《湿地科学》2014,(2):263-267

以8期Landset TM/ETM+遥感影像为数据源,利用归一化水指数,用地理信息系统相关软件,提取新疆艾比湖水域面积;利用湖泊面积动态模型和质心偏移模型,研究艾比湖的动态变化。结果表明,8个时期艾比湖面积在不断萎缩,湖泊总面积从1972年的583.14 km2减少到2011年的468.11 km2,缩小了19.73%;湖泊质心向东南方向偏移了1.23 km,表明艾比湖在退化。  相似文献   

Thickness distribution and extent of sea ice and snow in Prydz Bay and surrounding waters observed in 2012/2013 austral summer     

CHENG Peng  HAN Hongwei  LEI Ruibo  LI Zhijun  LU Peng 《极地研究(英文版)》2014,(1):1-9

Three ship-based observational campaigns were conducted to survey sea ice and snow in Prydz Bay and the surrounding waters(64.40°S–69.40°S, 76.11°E–81.29°E) from 28 November 2012 to 3 February 2013. In this paper, we present the sea ice extent and its variation, and the ice and snow thickness distributions and their variations with time in the observed zone. In the pack ice zone, the southern edge of the pack ice changed little, whereas the northern edge retreated significantly during the two earlier observation periods. Compared with the pack ice, the fast ice exhibited a significantly slower variation in extent with its northernmost edge retreating southwards by 6.7 km at a rate of 0.37 km?d-1. Generally, ice showed an increment in thickness with increasing latitude from the end of November to the middle of December. Ice and snow thickness followed an approximate normal distribution during the two earlier observations(79.7±28.9 cm, 79.1±19.1 cm for ice thickness, and 11.6±6.1 cm, 9.6±3.4 cm for snow thickness, respectively), and the distribution tended to be more concentrated in mid-December than in late November. The expected value of ice thickness decreased by 0.6 cm, whereas that of snow thickness decreased by 2 cm from 28 November to 18 December 2012. Ice thickness distribution showed no obvious regularity between 31 January and 3 February, 2013.  相似文献   

中国北部黄海近岸水体周丛硅藻的群落群集动态特征的研究     

Liu Yuanyuan  Zhang Wei  Xu Henglong 《海洋学报(英文版)》2014,33(9):160-165

The colonization features of periphytic diatoms were studied in coastal waters of the Yellow Sea, northern China from May to June 2010, using glass slides as an artificial substratum. Samples were collected at a time interval of 1, 3, 7, 10, 14, 21 and 28 d from two depths of 1 and 3 m. The dynamics of diatom colonization process had a similar pattern in community structure and fitted the logistic model in growth curve at both depths. The maximum abundance and the time for reaching 50% maximum abundance （10 d） showed no significant differences （P〉0.05） between two depths 1 and 3 m. Although the diatom communities repre- sented similar taxonomic composition, they differed in the temporal pattern of structural parameters and in succession dynamics of dominant species between the two layers. The species richness showed significantly higher values during the colonization period more than 14 d, while the species diversity and evenness rep- resented a higher variability with significantly different values （P〈0.05） at a depth of 1 m than at a deeper layer. The results suggest that the diatom colonization follows the logistic model growth curve and differs in colonization features between different depths in the coastal waters, and that the sampling strategy at i m is more effective to detect the ecological features for bioassessment in marine ecosystems.  相似文献   

Imagestation OrthoPro正射影像匀光实践     

汪飞 《测绘与空间地理信息》2014,(7):181-183

简述了Imagestation OrthoPro匀光原理,结合其原理分析了正射影像匀光过程中,大面积水域、屋顶等产生明显色差的原因,并用实验证明相关的改正方法,即适当调整kernel size或darken maximun参数项值,可有效避免水域等大面积亮区匀光后产生明显色差。  相似文献   

全国中小城市生态环境建设实验区即景——祝塘镇五福岛     

王琰 《今日国土》2009,(5):F0004-F0004

五福岛位于江阴市生态旅游项目的中心区域，由五条水域面积3000余亩的白荡湖相拥而成。面积2500余亩，现拟投资开发生态农业、生态绿化、旅游度假等项目。图为夕阳下的五福岛  相似文献   

粤东沿海养殖水域浮游植物的生态特征   总被引：10，自引：1，他引：9  

《广东海洋大学学报》2002,22(1):24-29

  相似文献   

中科院启动罗布泊历史上最大规模科考     

《地图》2009,(1):11-11

神秘的罗布泊百年来一直吸引着探险家的好奇。20世纪初，瑞典探险家斯文·赫定在《亚洲腹地探险8年》一书中写过：“这里使我惊讶，罗布泊像座仙湖，水面像镜子一样。”然而，这片被斯文·赫定赞誉过的水域在20世纪完全消失，罗布泊的环境在几十年间迅速恶化，成为“死亡之海”，上世纪80年代两位著名的探险家彭加木和余纯顺就接连在罗布泊遇难。  相似文献