Benthic Nutrient Recycling in Port Phillip Bay, Australia   总被引：8，自引：0，他引：8  

W.M. Berelson  D. Heggie  A. Longmore  T. Kilgore  G. Nicholson  G. Skyring 《Estuarine, Coastal and Shelf Science》1998,46(6):917-934

Benthic chamber measurements of the reactants and products involved with biogenic matter remineralization (oxygen, ammonium, nitrate, nitrite, phosphate, silicate, TCO₂and alkalinity) were used to define solute exchange rates between the sediment and overlying water column of Port Phillip Bay, Australia. Measurements at various sites throughout the bay, conducted during the summers of 1994 and 1995, indicate that the variability in flux values within a site is comparable to year-to-year variability (±50%). Four regions of the bay were distinguished by sediment properties and the northern region was identified as having 3–30 times greater nutrient regeneration rates than the other regions. Benthic recycling accounted for 63 and 72% of the annualized N and P input, respectively, to the entire bay as determined by summing benthic, dissolved riverine, atmospheric and dissolved effluent sources. However, bay-wide sedimentary denitrification accounted for a loss of 63% of the potentially recyclable N. This fraction is higher than many other coastal regions with comparable carbon loading. Denitrification efficiency is apparently not enhanced by benthic productivity nor by bio-irrigation. The rate of bio-irrigation is negatively correlated with denitrification efficiency. Bio-irrigation was studied using radon-222 and CsCl spike injection chamber measurements. Radon fluxes from sediments in Port Phillip Bay were enhanced over the diffusive flux by 3–16 times. The modelled rate of loss of Cs from chamber water was positively correlated with radon flux enhancement results. Both methods identify regions within Port Phillip Bay that have particularly high rates of non-diffusive pore-water overlying water solute exchange.  相似文献   

城市设计在青岛海岸规划中的应用   总被引：1，自引：0，他引：1  

吴碧君  胡泽建 《海岸工程》1998,17(1):59-63

在分析青岛海岸工程的特点及遍海岸工程对城市风貌影响影响的基础上,应用城市设计学对青岛的海岸规划与布局提出构想,并以沙子口海岸整治为例,提出滨海城市设计中适宜的岸线和海岸整治工程。  相似文献   

东海台风出现次数以及在我省沿海登陆的分析与预测     

周洪祥  方同德 《海洋学研究》1998,16(1):10-17

根据３７年（１９５３～１９８９年）的有关气象资料分析表明,浙北地区当年３月温度,上年４～６月降水量,秋、冬季干湿度和年积温与当年东海热带气旋（指强度达到热带风暴以上的热带气旋以下统称台风）出现次数之间有着密切的相关性。在此基础上进一步分析了前期一些气象要素与登陆台风之间的关系,并由此分别建立预报东海台风出现多寡和台风是否登陆的判别式。从其拟合和试报结果来看,效果令人满意。  相似文献   

海岸侵蚀灾害管理中的几项基础工作   总被引：5，自引：2，他引：3  

陈雪英  吴桑云 《海岸工程》1998,17(4):57-61

讨论了作为海岸带管理工作中一项重要管理内容──海岸侵蚀灾害管理中的几项基础性工作,主要讨论了灾害评估的意义;海岸侵蚀灾害管理基础图件和专业图件的名称及主要内容;建立海岸侵蚀灾害信息系统的意义和主要内容;关于海岸侵蚀灾害管理法的意义和急迫性;提出了建立禁建区和禁采区的意义和紧迫性,并指出在海岸带开发建设中要统一管理,全面规划,注意到海岸带生态环境的特殊性。总之在海岸侵蚀灾害管理中,首先要做好基础工作,在此基础上做好法制建设和依法管理。  相似文献   

英国的自然保护   总被引：2，自引：0，他引：2  

刘洪滨威廉.  阿 《海岸工程》1998,17(4):62-69

就英国自然保护区的八种主要类型：国家公园、国家风景区、自然遗产区、自然风景名胜区、遗产海岸、环境敏感区、特殊科学意义区、国家自然保护区;以及自然保护区的保护管理机构分别进行了概略介绍,以便有助于对英国自然保护区的了解。  相似文献   

江苏小庙洪牡蛎礁的地貌-沉积特征   总被引：6，自引：3，他引：6  

张忍顺 《海洋与湖沼》2004,35(1):1-7

利用卫星影象和野外实地勘察资料对江苏小庙洪牡蛎礁的地貌-沉积特征进行分析。结果表明，该牡蛎礁发育在强潮淤泥质潮坪上，造礁牡蛎主要是近江牡蛎和长牡蛎，表层的鲜活牡蛎为褶牡蛎。牡蛎礁区海水属盐度较高(27—30)的半成水，含沙量较大，为0．2—0．3g／L。活体牡蛎堆积体顶面高于周围潮间下带滩面1．0—1．5m。潮流较强，多在0．5—2．0m／s。海岸剖面可分为4个带，即礁后潮间带、潮沟、礁体生长带及礁前斜坡带。由于处于海岸侵蚀段，礁后潮坪缺失潮上带和大部分的潮间上带。礁后潮坪主要以粗粉砂为主，礁后潮沟冲淤变化较大，故礁体生长带时而为一沙洲，时而又与岸滩相连。礁体生长带分布在潮间下带，可看到独立的斑状礁体、带状礁体和大面积环状礁体群。环状礁的微地貌可以划分为礁塘(泻湖)、塘口和塘沟、塘口三角洲、礁墙和礁平台等。  相似文献   

海平面上升对长江三角洲海堤、航运和水资源的影响   总被引：2，自引：0，他引：2  

缪启龙  周锁铨 《南京气象学院学报》1999,22(4):625-630

分析了２０５０ 年长江三角洲地区相对海平面上升５０～７０ ｃｍ 时,将对该地区沿海海堤、航运及海岸带水资源的影响,并就相应的适应对策提出了建议。  相似文献   

我国东部滨岸侵沉变异规律初探     

李相然  姜传胜 《地质灾害与环境保护》1999,4(12):12

滨岸地带自然环境多变,地质环境极为脆弱,但在社会经济发展中起着极为重要的作用。着重分析我国东部滨岸侵沉变异特征,研究滨岸侵沉变异地域分异规律与成因规律。  相似文献   

Mudbank regime off the Kerala coast during monsoon and non-monsoon seasons     

R. Tatavarti  A. C. Narayana  P. Manoj Kumar  Shyam Chand 《Journal of Earth System Science》1999,108(1):57-68

Field experiments conducted in the nearshore ocean to understand the dynamics of mudbank off Kerala, south-west coast of India, are highlighted. Real time monitoring of the nearshore ocean off Purakkad, Kerala was accomplished using pressure transducers for nearshore surface wave measurements, and current sensors for nearshore velocity measurements. Comprehensive information on the spatial structure of mudbank was obtained from aerial surveys. Extensive data collected on surface waves and currents in the nearshore ocean, indicate that the infra-gravity (IG) waves (leaky modes and trapped edge wave modes), and far infra-gravity (FIG) waves coupled with strong shoreline reflections and undertow play an important role in the dynamics associated with the mudbanks off Kerala during the monsoon season. During the non-monsoon season evidence for progressive edge waves in the infragravity frequency band, an energetic gravity wave band and a strong undertow with weak reflections was observed.  相似文献   

经验模态法在中国沿岸海平面变化中的应用研究   总被引：4，自引：0，他引：4  

王卫强  陈宗镛  左军成 《海洋学报》1999,21(6):102-109

我国现代海平面变化的系统研究,开始于80年代前后,主要集中于海平面年变率和预测。早期所采用的方法有直线回归法、周期法外推预测等,之后有本征分析方法、随机动态预测模型及灰色系统方法等,以上方法各有利弊,但都因为不能较精确得到海平面变化中的各种周期变化而使得预测精度较差,尤其是对于海平面变化中较长周期的分辨方面。  相似文献