西太平洋雅浦-卡罗琳海区海山多尺度地形特征

海山地形的多尺度特征研究,有助于理解海山形成与演化过程中的地貌过程,并为深入认识俯冲带地球动力过程提供新的线索。本文基于中国科学院海洋研究所“科学”号科考船近年来在雅浦-卡罗琳海区采集的高分辨率海底地形数据,利用统计学及频谱分析等方法,分析了研究区42座海山的形态及地形粗糙度特征,并对海山地形多尺度特征及其成因开展研究。结果表明,雅浦-卡罗琳海区不同构造环境下形成的海山群,在海山的形态参数和多尺度地形特征等方面存在显著差异。相比于索罗尔海槽,帕里西维拉海盆中的海山具有更大的宽高比与更小的平坦度。两区域内海山形态参数具有不同的线性相关关系,表明区域内海山存在不同的形态演化过程。对帕里西维拉海盆中海山地形的频谱分析显示,其大尺度特征信号不显著,意味着该区域内海山地形受小尺度地貌过程的影响更大。索罗尔海槽中海山的粗糙度与海山体积具有线性相关性,可能与不同海山形成过程的差异有关,较早形成的海山受到了更多构造活动及小尺度地貌过程的影响,进而形成了更加粗糙的表面特征。     

基于SCI-E的国际海山生物多样性研究现状及研究热点解析

为了解海山生物多样性研究领域的研究现状和研究热点,本文采用文献计量学的方法对1991~2014年海山生物多样性相关的SCI论文产出进行了分析。结果表明,美国是该领域发文量最多的国家,新西兰水和大气国家研究所是发文量最多的机构。关键词分析的结果显示,海山生物多样性领域的研究热点主要集中在新物种发现和分类学,涉及"hydrothermal vent"(热液喷口)、"mitochondrial DNA"(线粒体DNA)及"conservation(保护)"等关键词的研究近几年逐渐增多。研究结果同时表明我国在该领域的研究较少,研究力度有待加强。     

基于淤涨速率的潮滩围垦适宜性评价

潮滩既具有重要的生态服务功能,亦是潜在的土地资源。过去几十年来,中国沿海潮间带的开发以围垦为主要驱动力,表现为海岸线主体向海推进。随着围垦规模和速度加快加大,出现了一系列生态、环境及土地利用问题,因此对于围垦适宜性的研究具有现实意义。本文以浙江省为例,利用遥感技术首先获取了大陆海岸线阶段性变化特征。接着从地貌均衡的角度,依据潮滩垂向淤涨速率和垂直岸线的潮滩剖面形态估算适宜的潮滩围垦速率。最后,比较海岸线实际推进速率与估算所得的围垦适宜速率,进行围垦适宜性分级评价。研究表明,1985-2015年间,围垦活动是浙江省大陆海岸线向海推进的主要原因。从时间进程来看,1985-1995年浙江省大陆海岸线向海推进缓慢,受围垦活动影响较小;1995-2015年间围垦活动频繁,人工岸线比例增加较多。围垦适宜速率的估算显示,杭州湾南岸围垦1 km后所需恢复时间最短,围垦适宜速率为12.5～64.3 m/a,其次为象山港和台州湾,围垦适宜速率分别为2.0～38.3 m/a和6.0～22.2 m/a;三门湾和温州湾围垦后所需恢复时间最长,围垦适宜速率分别为1.2～18.5 m/a和1.7～3.8 m/a。基于潮滩淤涨速率的围垦适宜性评价表明,1985-2015年间,浙江省主要围垦区域中围垦速率过快的是三门湾的下洋涂、蛇蟠岛和温州湾岸段,围垦速率较快区域为杭州湾南岸庵东浅滩部分岸段和象山港的莼湖镇、涂茨镇岸段以及台州湾的南洋涂,围垦速率略快的是庵东浅滩以及台州湾的北洋涂,围垦速率适宜的岸段仅有象山港的高湖塘和蒲门村岸段。浙江省过去30年的围垦进程和岸线变化启示,围垦活动应充分考虑潮滩环境的地貌动力均衡和自然恢复潜力。     

江苏沿海滩涂围垦现状及其对环境的影响

江苏沿海滩涂土地资源丰富,围垦活动较为频繁,了解围垦状况及其对环境的影响具有重要的现实意义。通过对江苏沿海围垦资料的统计,分析了建国后江苏沿海滩涂围垦的特点、目的和差异,并将之分为4个阶段;讨论了江苏沿海滩涂围垦的地区分布是以盐城为中心的不平衡状况,分析了围垦对江苏沿海自然环境及经济发展的影响;预测了江苏沿海滩涂围垦的发展方向,提出条子泥等地区是江苏沿海滩涂未来围垦的潜力地区。     

米草属植物Spartina angilica和Spartina alterniflora引种后江苏海岸湿地生态演化的初步探讨

选取江苏王港潮滩的盐蒿滩、大米草滩及互花米草滩,分析这三类滩面的地面以上生物量、初级生产力、动物洞穴参数和沉积物粒度,探讨大米草和互花米草引种区的湿地生态系统相对于盐蒿滩的变化.分析结果表明,互花米草滩的生物量远大于盐蒿滩和大米草滩;单位面积上动物洞穴数量相近,但洞穴大小有一定差异,互花米草滩动物洞穴稍大,数量也相对较多,这可能与初级生产力的提高有关.表层底质的粒径以互花米草滩为最细,盐蒿滩最粗,这种分布状况与互花米草引种前不同,说明互花米草促进了细颗粒物质的堆积.互花米草的引种在江苏海岸具有促淤和提高初级生产力的作用,而它对湿地生态系统的结构和功能的影响需要进一步研究.     

海岸带潮滩土壤含水量遥感测量

出露潮滩上土壤含水量的遥感测量是潮间带地形地貌测量方法的一种新尝试,也是对潮滩生态环境深层次认知的一条途径。借鉴陆地土壤含水量遥感监测的经验,通过分析实测潮滩土壤含水量与其光谱值的关系,建立出露潮滩上土壤含水量遥感监测模型,并利用该模型对研究区影像的土壤含水量进行反演尝试。研究结果为:(1)潮滩土壤含水量与光谱反射率的关系,波段的相关系数以ETM+4的相关性最大;(2)从多元线性模型、单波段模型、比值模型、仿植被指数模型的应用比较看,对于潮滩土壤含水量的遥感反演模型选用单波段模型的误差最小。结果表明,通过遥感测量和监测模型的反演,可以迅速得到海岸潮间带露滩上土壤含水量分布。     

Spatial and seasonal variations of sulphate,dissolved organic carbon,and nutrients in deep pore waters of intertidal flat sediments

Spatial and seasonal variations of sulphate, dissolved organic carbon (DOC), nutrients and metabolic products were determined down to 5 m sediment depth in pore waters of intertidal flats located in NW Germany. The impact of sediment permeability, pore water flow, and organic matter supply on deep pore water biogeochemistry was evaluated. Low sediment permeability leads to an enrichment of remineralisation products in pore waters of clay-rich sediments. In permeable sandy sediments pore water biogeochemistry differs depending on whether tidal flat margins or central parts of the tidal flat are studied. Pore water flow in tidal flat margins increases organic matter input. Substrate availability and enhanced temperatures in summer stimulate sulphate reducers down to 3.5 m sediment depth. Sulphate, DOC, and nutrient concentrations exhibit seasonal variations in deep permeable sediments of the tidal flat margin. In contrast, seasonal variations are small in deep pore waters of central parts of the sand flat. This study shows for the first time that seasonal variations in pore water chemistry are not limited to surface sediments, but may be observed down to some metres depth in permeable tidal flat margin sediments. In such systems more organic matter seems to be remineralised than deduced from surface sediment studies.     

Simulation of Wetting and Drying Processes in A Depth Integrated Shallow Water Flow Model by Slot Method

A particular porosity method named ＂slot method＂ is implemented in a depth-integrated shallow water flow model （DIVAST） to simulate wetting and drying processes. Discussed is the relationship between the shape factors of the ＂slot＂ and the preset depth used in ＂wetting-drying＂ algorithm. Two typical tests are conducted to examine the performance of the method with the effect of the shape factors of the ＂slot＂ being checked in detail in the first test. Numerical results demonstrate that： 1 ） no additional effort to improve the finite difference scheme is needed to implement ＂slot method＂ in DIVAST, and 2） ＂slot method＂ will simulate wetting and diying processes correctly if the shape factors of the ＂slot＂ being selected properly.     

热带西太平洋的小粟虫属的四种有孔虫(原生动物)的形态学研究以及Miliolinella obesa nov. spec. 新种描述

Foraminiferal oozes were sampled from the tropical West Pacific seamount and seabed of deep sea,by a remotely operated vehicle(ROV)in December 2014 and March 2016.Using standard morphological method,four Miliolinella species,including Miliolinella obesa,M.circularis,M.suborbicularis and M.subrotunda were described.Among the four species,M.obesa is a new species.It is a large member(about 500μm in length)of the genus.This species is characterized by having a very stout and transverse broadly circular outline,and its body width is greater than the body length.In addition,its chamber demarcations are obscure from the exterior appearance.Three chambers are unclearly visible on one side and two chambers are visible on the opposite.Finally,we provided very detailed taxonomic microphotographs and the ecological distribution information for each species.     

COASTAL SALT MARSHES AND MANGROVE SWAMPS IN CHINA

Based on plant specimen data,sediment samples,photos,and sketches from 45 coastal cross-sections,and materials from two recent countrywide comprehensive investigations on Chinese coasts and is-lands,this paper deals with China’s vegetative tidal-flats:salt marshes and mangrove swamps.Thereare now 141700 acres of salt marshes and 51000 acres of mangrove swamps which together cover about30% of the mud-coast area of the country and distribute between 18°N(Southem Hainan Island)and41°N(Liaodong Bay).Over the past 45 years.about 1750000 acres of salt marshes and 49400 acres ofmangrove swamps have been reclaimed.The2.0×10~9 tons of fine sediments input by rivers into the Chinese seas form extensive tidal flats,the soil basis of coastal helophytes.Different climates result inthe diversity of vegetation.The 3～8m tidal range favors intertidal zone development.Of over 20plant species in the salt marshes,native Suaeda salsa,Phragmites australis,Aeluropus littoralis,Zoysiamaerostachys,Imperata cylindrica and in