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51.
东营港内航道淤积问题一直未能很好解决。在对该港内航道淤积原因及其影响因素进行研究分析基础上 ,为今后的工程建设提出了一些应采取的对策措施  相似文献   
52.
沙埕港流域物产丰富,目前因电力紧缺多未开发。该港潮汐能源多,地形、地质条件利于建站工程,故拟在百尺门、长屿两处建潮汐电站,并与当地水电等联合运行,可收发电、矿产、水产、航运交通以及农、林、副业等多方面综合利用效益。  相似文献   
53.
BacterialkineticsandenvironmentalcapacityinheWesternXiamenHarbour¥YeDezan;NiChunzhi;ZhouZongcheng;YaoRuimei;ZengHuoshui;LinYa...  相似文献   
54.
海南岛洋浦港潮汐汊道口门的均衡过水面积   总被引:5,自引:1,他引:5  
高抒  张红霞 《海洋与湖沼》1994,25(5):468-476
将汊道均衡与潮汐特征,纳潮量,淡水径流量及沉积物搬运格局相联系,确定了洋浦港的均衡条件,根据纳潮盆地的水面面积-水面高程曲线以及相关的特征潮位估算平均纳潮量,利用1977-1979年波浪观测资料和CERC公式计算沿岸输沙率;此外,还用改进的Gadd公式确定口门涨、落潮流输沙率,计算中引入汊道口门流速频率分布函数的定义。由此而得洋浦港均衡过水面积为5800m^2,与O'Brien方法所得结果相比,本  相似文献   
55.
A central question to any understanding of ecology is how animals use their habitat, and how habitat use is influenced by temporally changing features of the environment. Previous research on Hector's dolphins at Akaroa Harbour, New Zealand suggested that dolphins leave inshore, harbour environments during or after rough weather. To test this hypothesis, visual sightings (2000–2012) and acoustic detections (2007–2008) of Hector's dolphins in Akaroa Harbour were modelled to test for a relationship with swell height and swell direction. Sighting rates and acoustic detection rates in Akaroa Harbour were significantly lower on days after big swell events and in some linear models after swell events from the south. These results indicate that swell events influence Hector's dolphin movements in and around Akaroa Harbour. Possible reasons for this behaviour are diverse and need further investigation. However, this information can be used both to predict daily dolphin movement for conservation and research purposes, and to suggest how dolphins may react in future if extreme weather events are becoming frequent.  相似文献   
56.
The Kaipara Harbour in New Zealand is one of the largest estuarine systems in the world, containing significant areas of subtidal seagrass habitat (Zostera muelleri). Light availability at the maximum depth limit for Z. muelleri was measured at 2.10 (0.19 SEM) and 4.91 (0.53 SEM) mol photons m?2 d?1 during the winter and summer monitoring periods, respectively. The primary drivers of benthic light availability were found to be surface light availability, the timing of the low tide and water clarity. Core sampling analysis suggested that biomass of seagrass growing at the maximum depth limit was low, indicative of light limitation. The results of this study suggest that the subtidal distribution of seagrass in the Kaipara Harbour is light-limited and that reductions in water clarity due to changes in land use are likely to result in significant reductions in the extent and productivity of subtidal seagrass habitat.  相似文献   
57.
This paper presents the results of the statistical analysis of a set of physico-chemical and biological water quality parameters, monthly collected from 2000 to 2007 in the Genoa Harbour area (Ligurian Sea). We applied multivariate methods, such as principal component analysis (PCA) and dynamic factor analysis (DFA) for investigating the spatial and temporal variability and for providing important background information on pollution problems in the region. PCA evidenced the role of the sewage and river discharges and of the exchanges with the open sea in determining the harbour water quality. DFA was used to estimate underlying common trends in the time series. The DFA results partly show a general improvement of water quality over the 8-years period. However, in other areas, we found inter-annual variations but no significant multi-annual trend. Furthermore, we included meteorological variables in our statistical analyses because of their potential influence on the water quality parameters. These natural forcings explain part of the variability in water quality parameters that are superimposed on the dominating anthropogenic pollution factors.  相似文献   
58.
象山港避风锚地工程潮流泥沙模型试验研究   总被引:2,自引:1,他引:1       下载免费PDF全文
在分析现场实测资料的基础上,借助象山港整体变态物理模型,通过潮汐水流定床和悬沙淤积试验,对湾内拟建奉化市避风锚地工程实施后,附近海域的潮流场变化和海床淤积情况进行了系统研究。研究结果表明,避风锚地工程对航道、渔港等周边重要设施的影响有限。从而为工程的海洋环评、海域使用论证及工程设计提供了技术支撑,也为半封闭港湾内其它类似涉海工程的可行性论证提供了可借鉴的经验。  相似文献   
59.
2010年9月3日16时35分46秒新西兰南岛Greendale附近发生了Mw7.0地震,震源深度约10.0 km.2011年2月21日新西兰南岛又发生了Mw6.1地震,为2010年Mw7.0主震后最大的一次余震,震源深度约5.0 km,发震断层为Christchurch南约9 km一条近东西走向逆冲的隐伏断层,该地震造成Christchurch城内多处建筑物严重损毁.本文分析了2010年新西兰地震事件Mw7.0主震与Mw6.1余震强地面运动的特征.新西兰Mw6.1余震近场强地面运动整体高于Mw7.0主震.将主震和余震的强震观测记录分别与新一代衰减关系(NGA)进行对比,发现余震强震观测数据整体高于其震级对应的NGA.分别选取距离主震和余震震中最近且强震观测记录最高的两个台站(GDLC台站和HVSC台站)作为参照台站,建立动态复合震源模型(DCSM)及有限断层随机振动模型(SFFM)进行强地面运动的模拟计算,分析两种模型的模拟结果并对比二者的优势及局限,以便在未来工作中更好地通过模型计算强地面运动特征,实现区域化特征快速、实时分析及局部重点、细致分析相结合的目标.  相似文献   
60.
This article takes circumstances of post-quake Christchurch as an analogue for Anthropocene emergency. I argue that Christchurch events are more than a reminder of the Earth's geologic volatility; for the Anthropocene-as-disaster, it is a prompt to contemplate what it is to dwell on unstable ground. Urban locations—towns, cities, mega-cities—are all rendered vulnerable on the surface of an unruly planet, offering no absolute refuge from planetary fluctuations. Such unsettling is deeply felt, physically and psychologically, resulting in homelessness both literal and figurative. Ensuing analysis offers insight into potential strategies for unsettled planetary dwelling to come.  相似文献   
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