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Migration patterns and habitat use of the tapertail anchovy Coilia mystus in the Oujiang River Estuary and the Zhujiang River Estuary, China 预览
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作者 Tao Jiang Hongbo Liu +1 位作者 Honghui Huang Jian Yang 《海洋学报:英文版》 SCIE CAS CSCD 2019年第8期35-40,共6页
Habitat use of the tapertail anchovy(Coilia mystus Linnaeus, 1758) from the Oujiang River Estuary and the Zhujiang(Pearl) River Estuary was studied by examining the environmental signatures of Sr and Ca in otoliths us... Habitat use of the tapertail anchovy(Coilia mystus Linnaeus, 1758) from the Oujiang River Estuary and the Zhujiang(Pearl) River Estuary was studied by examining the environmental signatures of Sr and Ca in otoliths using electron probe microanalysis. Individuals from the Oujiang River had higher and varied Sr:Ca ratios(expressed as(Sr:Ca)×1 000, 3.83–13.0 average) in the otolith core regions, suggesting that they were born in brackish or sea waters, and that a freshwater habitat might not be necessary for egg hatching and larval growth.While, individuals from the Zhujiang River had lower Sr:Ca ratios(0.39–2.51 average) in the core regions,suggesting a freshwater origin. After hatching, anchovies from the Zhujiang River migrate downstream to the river estuary close to brackish water. Our results demonstrated varied habitat use for spawning during stages of early life history between the two populations, and suggested that such variations are promoting diversity of life history strategies of this species. 展开更多
关键词 Coilia mystus Oujiang RIVER ESTUARY Zhujiang(Pearl) RIVER ESTUARY HABITAT use OTOLITH MICROCHEMISTRY
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Sediment Transport Capacity Under the River-Tide Interaction in the Changjiang Estuary 预览
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作者 FENG Zhi-yong TAN Guang-ming XIA Jun-qiang 《中国海洋工程:英文版》 SCIE EI CSCD 2019年第2期207-218,共12页
Sediment transport capacity is a fundamental parameter in sediment transport theory and its accurate calculation is important from both theoretical and engineering viewpoints. The capacity of sediment transport has be... Sediment transport capacity is a fundamental parameter in sediment transport theory and its accurate calculation is important from both theoretical and engineering viewpoints. The capacity of sediment transport has been studied extensively by many researchers in the last decades. Nevertheless, the underlying mechanism behind sediment transport capacity in estuaries remains poorly understood. The current study aims to explore the impact of the river–tide interaction on sediment transport and establish a formula of sediment transport capacity under the river–tide interaction. The impact of the river–tide interaction on the hydrodynamics and sediment dynamics in the Changjiang Estuary was analyzed, a practical method for describing the variation in tide-runoff ratio was established, and a formula of sediment transport capacity considering the impact of river–tide interaction was proposed by introducing the tide-runoff ratio. The new method bridged the gap between two well-known sediment transport capacity methods by considering the variation in the index a for the gravitational term and overcomes the drawback of distinguishing flood/dry season or spring/ebb tide in the calculation of estuarine sediment transport. A large amount of flow and sediment data obtained from the Changjiang Estuary were collected to verify the proposed formula. The effect of salt-fresh water mixture and the morphological evolution on sediment transport capacity of the Changjiang Estuary were discussed. 展开更多
关键词 SEDIMENT transport capacity RIVER TIDE INTERACTION hydrodynamics and SEDIMENT dynamics Changjiang ESTUARY (Yangtze Estuary)
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滨湖城市典型公园化河口岸带土壤理化性状研究 预览
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作者 乔红霞 蒋媛 +3 位作者 付子轼 王俊力 张镭 刘福兴 《土壤》 CAS CSCD 北大核心 2019年第3期507-516,共10页
为摸清五里湖公园化河口岸带土壤理化性质,探明土壤质量状况,本研究于2017年10月对五里湖3个典型公园化河口区域(陆典桥浜L、梁塘河C、圩田里河W)的24个点位进行岸带土壤采集,分析土壤颗粒组成、容重(BD)和孔隙度(Pt)等物理性状和pH、... 为摸清五里湖公园化河口岸带土壤理化性质,探明土壤质量状况,本研究于2017年10月对五里湖3个典型公园化河口区域(陆典桥浜L、梁塘河C、圩田里河W)的24个点位进行岸带土壤采集,分析土壤颗粒组成、容重(BD)和孔隙度(Pt)等物理性状和pH、有机质(OM)、全氮(TN)、碱解氮(AN)、全磷(TP)和有效磷(AP)等化学性状,并利用与植物生长相关的土壤指标(石砾、砂粒、黏粒、BD、pH、OM、TN、AN、TP、AP)进行土壤质量指数(SQI)评价.结果表明:①3个河口岸带土壤均存在结构退化的情况,土壤主要以石块和石砾为主(>700 g/kg),砂粒、粉粒和黏粒含量较低,土壤容重偏大(>1.35 g/cm3),孔隙度偏低(<50%);②3个河口岸带土壤pH均呈碱性(平均8.30),且陆典桥浜河口>圩田里河河口>梁塘河河口,AP含量趋势相反;除梁塘河河口TP含量差异不大外,陆典桥浜和梁塘河河口的OM、TN、AN、AP、TP均呈现近岸大于远岸的趋势.③3个河口岸带土壤质量状况均较差(SQI<0.5),AN、BD、OM、AP和pH是影响研究区域岸带土壤质量的5个主因子. 展开更多
关键词 河口 岸带 土壤 理化性质 土壤质量指数(SQI)
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Estuarine shoreline change analysis along The Ennore river mouth,south east coast of India,using digital shoreline analysis system
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作者 Nithu Raj B.Gurugnanam +1 位作者 V.Sudhakar Pereira Glitson Francis 《大地测量与地球动力学:英文版》 2019年第3期205-212,共8页
Ennore river mouth is the largest estuary and it’s located in Thiruvallur, Tamil Nadu, southeastern part of India. The creek covers an area of 2.25 km2 where located 20 km north of the city centre and 2.6 km south of... Ennore river mouth is the largest estuary and it’s located in Thiruvallur, Tamil Nadu, southeastern part of India. The creek covers an area of 2.25 km2 where located 20 km north of the city centre and 2.6 km south of the Ennore port. The studies are carried out using remote sensing and Geospatial technologies.The Landsat images acquired from 2013 to 2016 were used to demarcate the rate of shoreline dynamics using GIS-based digital shoreline analysis system. The succeeding short term river mouth dynamics,coastal erosion, and accretion rates have been considered for the years 2013-2016. The statistical analysis such as linear regression and end point rate were determined from the shoreline layers. The physical parameters are played the main role in the dynamic activities of erosion and accretion. The study area shows during last four years(2013-2016) erosion are more than the accretion of the shoreline occurred over the years. 展开更多
关键词 River MOUTH changes EROSION ACCRETION DSAS Ennore ESTUARY
Response of size-fractionated phytoplankton to environmental factors near the Changjiang Estuary 预览
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作者 Li Li Jingyi Cen +1 位作者 Lei Cui Songhui Lu 《海洋学报:英文版》 SCIE CAS CSCD 2019年第1期151-159,共9页
Size-based partitioning of phytoplankton is a useful tool for monitoring key phytoplankton traits, and it provides a better understanding of phytoplankton dynamics. Our aim is to determine the variation in the differe... Size-based partitioning of phytoplankton is a useful tool for monitoring key phytoplankton traits, and it provides a better understanding of phytoplankton dynamics. Our aim is to determine the variation in the different size classes of phytoplankton to the total phytoplankton biomass during the spring and autumn of 2010 and examine the relationship between phytoplankton size structure and environmental variables and zooplankton community structure near the Changjiang Estuary. In the spring, phytoplankton populations were predominantly consisted of nanophytoplankton throughout the study region. In the autumn, picophytoplankton and nanophytoplankton collectively dominated the phytoplankton community. A Pearson correlation analysis highlighted the role of temperature and trophic conditions on the contributions of nanophytoplankton and picophytoplankton. The grazing pressure exerted by mesozooplankton could have played an important role in determining the microphytoplankton community structure. 展开更多
关键词 PHYTOPLANKTON size structure temperature TROPHIC condition seasonal SUCCESSION CHANGJIANG Estuary
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Modeling of suspended sediment by coupled wave-current model in the Zhujiang(Pearl)River Estuary 预览
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作者 Guangping Liu Shuqun Cai 《海洋学报:英文版》 SCIE CAS CSCD 2019年第7期22-35,共14页
A three-dimensional wave-current-sediment coupled numerical model is developed to understand the sediment transport dynamics in the Zhujiang(Pearl)River Estuary(ZRE),China.The model results are in good agreement with ... A three-dimensional wave-current-sediment coupled numerical model is developed to understand the sediment transport dynamics in the Zhujiang(Pearl)River Estuary(ZRE),China.The model results are in good agreement with observed data,and statistics show good model skill scores.Numerical studies are conducted to assess the scenarios of suspended sediment in the ZRE under the effects of different forcing(river discharges,waves,and winds).The model results indicate that the estuarine gravitational circulation plays an important role in the development of estuarine turbidity maximum in the ZRE,particularly during neap tides.The increased river discharge can result in a seaward sediment transport.The suspended sediment concentration(SSC)in the bottom increases with both wave bottom orbital velocity and wave height.Because of the shallow water depth,the effect of waves on sediment in the west shoal is greater than that in the east channel.The southwesterly wind-induced wave affects the SSC more than those resulting from the northeasterly wind,while the northeasterly wind-driven circulation has a slightly greater influence on the SSC than that of the southwesterly wind.However,a steady southwesterly wind condition favors the increase of the SSC in the Lingding Bay more so than a steady northeasterly wind condition.If the other forcings are same,the averaged SSC under a steady southwesterly wind condition is about 1.1 times that resulting from a steady northeasterly wind. 展开更多
关键词 sediment transport TURBIDITY Regional OCEAN Modeling System(ROMS) Zhujiang River ESTUARY
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Numerical simulation of hydrodynamic environment effects of the reclamation project of Nanhui tidal flat in Yangtze Estuary 预览
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作者 Di-fan Cao Yong-ming Shen +1 位作者 Mei-rong Su Chun-xue Yu 《水动力学研究与进展:英文版》 SCIE EI CSCD 2019年第3期603-613,共11页
The reclamation is the main method in the coast exploitation, and the assessment of the hydrodynamic environment effect of the reclamation project is important for project's site selection and environmental protec... The reclamation is the main method in the coast exploitation, and the assessment of the hydrodynamic environment effect of the reclamation project is important for project's site selection and environmental protection. With consideration of the baroclinic water, a 3?D numerical model MIKE3 is applied to simulate Yangtze Estuary's hydrodynamic environment to predict the impacts of the reclamation project of the Nanhui tidal flat. The simulated results of the model agree well with the field data of the tide level, the current speed, the current direction, the temperature, the salinity and the water quality, and it is indicated that after the reclamation project, the high tide level will be lower, while the low tide level will be higher in the South Branch in general. During the spring tide in the dry season, the peak velocity during the ebb tide in the North Channel will be reduced by 13%, while it will be increased by 21% in the South Channel in average. The salinity will be increased in the North Channel, while reduced in the South Passage, besides, the reclamation project will aggravate the saltwater intrusion of the North Branch. The value of N/P will be increased by about 4% in the whole South Branch except for the North Channel, leading to a slight aggravation of the phosphorus restriction effect in the Yangtze Estuary. 展开更多
关键词 YANGTZE ESTUARY 3-D numerical model HYDRODYNAMICS NUTRIENTS RECLAMATION project
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Changes in Sedimentation Rate of Tidal Flat and Environmental Significance at Qidong Foreland of the Yangtze Estuary 预览
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作者 Yunfeng ZHANG Zhenke ZHANG +1 位作者 Hang REN Yingying CHEN 《亚洲农业研究:英文版》 2019年第6期33-39,共7页
The sedimentation rate is an important environmental parameter to understand the evolution of coastal geomorphology. The tidal flat around Qidong foreland is located in the junction between Yangtze Estuary and Jiangsu... The sedimentation rate is an important environmental parameter to understand the evolution of coastal geomorphology. The tidal flat around Qidong foreland is located in the junction between Yangtze Estuary and Jiangsu coast,where the land-ocean interactions are strong and highly sensitive to environmental changes. The QDZ-1 core sediments collected at Qidong foreland was analyzed for137 Cs dating and grain size.The results showed that silt is the main sedimentary type with a trend of gradually fining from the bottom to the top,conforming to the sedimentation characteristic of the silt muddy tidal flat. The sedimentation rate could be divided into three distinct stages: 1963 to 1986 was 2. 61 cm/yr,1963 to 2011 was 1. 82 cm/yr,and 1986 to 2011 was 1. 10 cm/yr. Based on these,further explanation was made for the significance of environmental changes. According to the estimation of sedimentation rate,the impact of extreme environmental change was reflected by the sudden increase in sand proportion at the depth of 172. 5 cm. Since the introduction of Spartina alterniflora in the 1970 s,it has played an important role in tidal flat development. The tidal flat has a high sedimentary rate during this time. With continuous accretion of the tidal flat,low tidal flat turns to high tidal flat,the sedimentation rate gradually declines,and tidal flat sedimentation appears. 展开更多
关键词 The Yangtze ESTUARY TIDAL flat at Qidong FORELAND SEDIMENTATION rate 137 Cs DATING Environmental significance
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斜压作用对河口落潮水流剖面的影响 预览
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作者 陈鹏 张卓 +1 位作者 宋志尧 李玉婷 《水运工程》 北大核心 2019年第7期38-43,92共7页
在咸淡水混合的河口由于水体密度在空间不均匀分布,水流受到斜压影响,其流速分布经常会偏离传统的对数分布。而常用的密度流分布基于常涡黏系数假定,无法用于瞬时流速剖面的拟合。基于水动力方程,得出考虑斜压影响下的湍流切应力分布,... 在咸淡水混合的河口由于水体密度在空间不均匀分布,水流受到斜压影响,其流速分布经常会偏离传统的对数分布。而常用的密度流分布基于常涡黏系数假定,无法用于瞬时流速剖面的拟合。基于水动力方程,得出考虑斜压影响下的湍流切应力分布,分析发现在斜压影响下的湍流切应力呈抛物线分布。在此基础上应用Prandtl混合长理论,提出考虑河口斜压影响的落潮水流流速剖面。通过比较数值模拟结果与实测资料,发现本文公式能很好地校正斜压引起流速剖面对于传统对数分布的偏差,提高拟合精度,得到更趋于合理的拟合参数。 展开更多
关键词 斜压 流速分布 河口 对数分布 摩阻流速
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珠江三角洲河口湾航道整治研究 预览
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作者 申其国 谢凌峰 +1 位作者 解鸣晓 王亚妮 《水道港口》 2019年第3期286-292,共7页
基于珠江三角洲河口湾主要航道的现状情况,在分析航道回淤影响的基础上,对航道选线、整治思路等相关航道整治问题进行了研究。认为河口湾航道回淤受上游水沙条件、潮流波浪情况、采沙等人类活动等因素影响,台风骤淤情况不明显。航道选... 基于珠江三角洲河口湾主要航道的现状情况,在分析航道回淤影响的基础上,对航道选线、整治思路等相关航道整治问题进行了研究。认为河口湾航道回淤受上游水沙条件、潮流波浪情况、采沙等人类活动等因素影响,台风骤淤情况不明显。航道选线宜选择天然深槽、走向与潮流动力线一致、尽量避开强浪区。整治措施宜采用疏浚结合局部碎岩清礁,宜分期实施。广州港出海航道和崖门出海航道有进一步提升等级的空间,铜鼓航道可考虑适当调整航槽位置,横门出海航道与九洲港航道开发深水航道的时机和条件尚不成熟、近期不宜过度开发。对河口湾的航道开发与港口建设具有重要的参考价值。 展开更多
关键词 珠江三角洲 河口湾 航道整治 回淤
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Variation of Zooplankton Ecological Group During Spring in China Estuaries 预览
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作者 LU Wuyang GAO Qian XU Zhaoli 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第2期501-508,共8页
Zooplankton was major indicator species of the environment.To explore the effect of marine environment on zooplankton distribution in the coast of China,the zooplankton samples from stations in Guanhe Estuary(GE),Chan... Zooplankton was major indicator species of the environment.To explore the effect of marine environment on zooplankton distribution in the coast of China,the zooplankton samples from stations in Guanhe Estuary(GE),Changjiang(Yangtze River)Estuary(CE),Oujiang Estuary(OE),Jiulongjiang Estuary(JE)and Beilun Estuary(BE)(covering 14 latitudes)in spring were surveyed and the variation of zooplankton ecological group was researched.According to the adaptability temperature,the zooplankton was divided into two ecological groups:warm-temperate species and subtropical species.The warm-temperate species was the main dominant species and subtropical species was only dominant species in BE.Calanus sinicus,a warm-temperate species,was the only dominant species in all five estuaries.From north to south,the proportion of warm-temperate species in the five estuaries gradually decreased depends on the number,were 83.33%,48.39%,45.00%,43.75%and 30.43%,respectively.In contrary,the proportion of subtropical species was gradually increased.The warm-temperate species predominated over the total abundance and the percentage was whopping high in the north estuaries,including GE(96.16%),CE(95.57%),OE(97.83%)and JE(95.53%).The abundance percentage of subtropical species have remarkably higher(82.39%)in BE.Five estuaries zooplankton community was subdivided into three zooplankton groups,which were the northern warm temperate zooplankton group,the southern subtropical zooplankton group and the estuarine brackish-water group.The water temperature and coastal current of China Sea are recognized as the main factors determining the distribution and community structure of estuarine zooplankton in spring. 展开更多
关键词 ZOOPLANKTON ESTUARY ECOLOGICAL GROUP SPRING
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Stable Carbon Isotope and Long-Chain Alkane Compositions of the Major Plants and Sediment Organic Matter in the Yellow River Estuarine Wetlands 预览
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作者 ZHANG Tao WANG Xuchen 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第3期735-742,共8页
Elemental(TOC,TN,C/N)and stable carbon isotopic(δ^13C)compositions and long-chain alkane(n C16-38)concentrations were measured for eight major plants and a sediment core collected from the Yellow River estuarine wetl... Elemental(TOC,TN,C/N)and stable carbon isotopic(δ^13C)compositions and long-chain alkane(n C16-38)concentrations were measured for eight major plants and a sediment core collected from the Yellow River estuarine wetlands.Our results indicate that both C3(-25.4‰to-29.6‰)and C4(-14.2‰to-15.0‰)plants are growing in the wetlands and C3 plants are the predominant species.The biomass of the wetland plants had similar organic carbon(35.5-45.8%)but very different organic nitrogen(0.35-4.15%)contents.Both C3 and C4 plants all contained long-chain alkanes with strong odd-to-even carbon numbered chain predominance.Phragmites australis,a dominant C3 plant contained mainly n C29 and n C31 homologues.Aeluropus littoralis,an abundant C4 plant were concentrated with n C27 and n C29 homologues.Organic matter preserved in the Yellow River estuarine sediments showed strong terrestrial signals(C/N=11-16,δ^13C=-22.0‰to-24.3‰).The distribution of long-chain n-alkanes in sediments also showed strong odd-to-even carbon chain predominance with n C29 and n C31 being the most abundant homologues.These results suggest that organic matter preserved in the Yellow River estuarine sediments were influenced by the wetland-derived organic matter,mainly C3 plants.The Yellow River estuarine wetland plants could play important role affecting both the carbon and nutrient cycling in the estuary and adjacent coastal waters. 展开更多
关键词 Yellow River Estuary wetland PLANTS sediments N-ALKANES carbon isotopes
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Trophic functioning of macrobenthic fauna in a tropical acidified Bornean estuary(Southeast Asia) 预览
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作者 Mohammad Belal Hossain 《国际泥沙研究:英文版》 SCIE 2019年第1期48-57,共10页
The trophic structure of a community is used to infer ecosystem functioning(e.g.energy transfer and nutrient cycling).Here the trophic structure of the benthic infaunal and epifaunal communities in the Brunei Estuary ... The trophic structure of a community is used to infer ecosystem functioning(e.g.energy transfer and nutrient cycling).Here the trophic structure of the benthic infaunal and epifaunal communities in the Brunei Estuary are characterized,and their distribution along an estuarine pH gradient is analyzed using univariate and multivariate techniques.This analysis revealed that surface deposit feeders(e.g.,polychaetes)were numerically dominant within the infaunal communities whereas in the epifaunal communities filter feeders(e.g.,bivalves)were highly abundant.Species richness for almost all trophic groups increased toward the lower estuary,except for omnivores in the epifaunal communities,which decreased markedly.Both Analysis of Variance(ANOVA)and Analysis of Similarities(ANOSIM)detected significant differences in the density of respective trophic groups among stations.Within infaunal communities,both Biological and Environmental procedure(BIO-ENV)and Canonical Correspondence Analysis(CCA)showed that trophic shifts were associated with environmental gradients.Surface-deposit feeders and omnivores were the most abundant macrobenthos of the upper estuary characterized by low salinity,low pH,and a higher percentage of mud particles.The proportion of filter feeders and carnivores increased with salinity/pH and sand.A more uniform distribution of trophic structure was found in the lower estuary,with high salinity and pH over sandy habitat.In contrast,within epifaunal trophic groups,the percentage of surface deposit feeders and omnivores declined,but filter feeders remarkably increased toward the sea.The proportion of carnivores remained similar at all stations.Non-Metric Multidimensional Scaling(nMDS)ordination for epifaunal trophic groups clearly demarcated higher salinity/pH stations from lower salinity/pH stations,suggesting different trophic compositions along the estuarine pH gradient. 展开更多
关键词 Macrobenthic COMMUNITIES TROPHIC structure Environmental factors ACIDITY TROPICAL ESTUARY
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Physical processes causing the formation of hypoxia off the Changjiang estuary after Typhoon Chan-hom,2015 预览
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作者 GUO Yaru RONG Zengrui +3 位作者 LI Bo XU Zhao LI Pixue LI Xiaodan 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第1期1-17,共17页
Severe hypoxia was observed in the submarine canyon to the east of the Changjiang estuary in July 14,2015,two days after typhoon Chan-hom.The oxygen concentration reached as low as 2.0 mg/L and occupied a water column... Severe hypoxia was observed in the submarine canyon to the east of the Changjiang estuary in July 14,2015,two days after typhoon Chan-hom.The oxygen concentration reached as low as 2.0 mg/L and occupied a water column of about 25 m.A ROMS model was confi gured to explore the underlying physical processes causing the formation of hypoxia.Chan-hom passed through the Changjiang estuary during the neap tide.The stratifi cation was completely destroyed in the shallow nearshore region when typhoon passing.However,it was maintained in the deep canyon,though the surface mixed layer was largely deepened.The residual water in the deep canyon is considered to be the possible source of the later hypoxia.After Chan-hom departure,not only the low salinity plume water spread further off shore,but also the sea surface temperature(SST)rewarmed quickly.Both changes helped strengthen the stratifi cation and facilitate the formation of hypoxia.It was found that the surface heat fl ux,especially the solar short wave radiation dominated the surface re-warming,the off shore advection of the warmer Changjiang Diluted Water(CDW)also played a role.In addition to the residual water in the deep canyon,the Taiwan Warm Current(TWC)was found to fl ow into the deep canyon pre-and soon post-Chan-hom,which was considered to be the original source of the hypoxia water. 展开更多
关键词 HYPOXIA CHANGJIANG estuary deep CANYON vertical mixing advection heat fl ux
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2017年夏季北海市冯家江入海口红树林潮间带大型底栖动物群落结构及多样性
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作者 刘士龙 秦旭东 +1 位作者 王广军 蒋爱伍 《湿地科学》 CSCD 北大核心 2019年第3期352-358,共7页
大型底栖动物作为迁徙鸟类重要的食物来源,维持着红树林生态系统中许多重要的生态过程。为了揭示夏季广西北海滨海国家湿地公园群落结构及多样性,于2017年6月,在广西北海滨海国家湿地公园内冯家江入海口红树林潮间带,从冯家江入海口向... 大型底栖动物作为迁徙鸟类重要的食物来源,维持着红树林生态系统中许多重要的生态过程。为了揭示夏季广西北海滨海国家湿地公园群落结构及多样性,于2017年6月,在广西北海滨海国家湿地公园内冯家江入海口红树林潮间带,从冯家江入海口向东依次布设了5个断面,在调查断面中采集泥样或砂样,经筛选和鉴定,共得到大型底栖动物31种,隶属于4门7纲11目21科,其中,软体动物门的物种数最多,节肢动物门的物种数次之,软体动物对总生物量做出的贡献最大,纵带滩栖螺(Batillaria zonalis)和突畸心蛤(Cryptonema producta)为调查区域的优势种;大型底栖动物的平均生物量为245.12 g/m^3,平均密度为172.54 ind./m^3;5个断面的大型底栖动物群落的Shannon-Wiener指数介于2.01~3.01之间,表明水体被轻度污染,河口处断面的大型底栖动物群落的多样性水平最高,垃圾堆放场附近断面的多样性水平最低,5个断面的大型底栖动物群落的优势种以纵带滩栖螺、珠带拟蟹守螺(Cerithidea cingulate)和沙蚕(Nereis succinea)等耐污种为主。与北部湾其它地区相比,研究区域的大型底栖动物总物种数明显偏少。近年来,广西北海滨海国家湿地公园受到垃圾堆放场和人类活动的负面影响较大,冯家江入海口附近水体出现了一定程度的污染,导致其大型底栖动物群落结构发生了改变。 展开更多
关键词 大型底栖动物 多样性 红树林 垃圾堆放场 河口 广西北海
A Call for Economic Integration
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作者 Zhang Shasha Wang Hairong 《北京周报:英文版》 2019年第14期32-35,共4页
In the past, for residents of Boao, then a fishing village sitting on an estuary in China's southernmost Hainan Island, the world was a remote, inaccessible place on the other side of the raging sea.
关键词 PAST ESTUARY
Monitoring and Evaluation of Environmental Quality of the Waters near the Feiyun River Estuary in Wenzou in Recent Years 预览
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作者 Yao Dongping Lin Bo +2 位作者 Zhang Haifeng Zheng Fangqin Ye Xinrong 《气象与环境研究:英文版》 CAS 2019年第4期100-105,109共7页
Based on the monitoring results of environmental quality of the waters near the Feiyun River estuary during 2011-2016, the current situation of environmental quality of the waters was analyzed and evaluated. The resul... Based on the monitoring results of environmental quality of the waters near the Feiyun River estuary during 2011-2016, the current situation of environmental quality of the waters was analyzed and evaluated. The results showed that pH, DO, COD Mn , petroleum, and heavy metals (Cu, Pb, Zn, Cd, Hg, As and Cr) in the waters near the Feiyun River estuary did not exceed the second-class standard of Seawater Quality Standard (GB 3097-1997), while both inorganic nitrogen and reactive phosphate in the waters exceeded the second-class standard obviously. The water quality of the waters near the Feiyun River estuary was in an eutrophic state. In terms of sediment quality, the standard index of most evaluation factors except for Cu was smaller than 1, meeting the demands of sediment quality for environmental protection. 展开更多
关键词 WATERS NEAR the Feiyun River ESTUARY Current situation of environmental QUALITY Evaluation Features of water QUALITY EUTROPHICATION
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Fast acclimation of phytoplankton assemblies to acute salinity stress in the Jiulong River Estuary 预览
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作者 Gang Li 《海洋学报:英文版》 SCIE CAS CSCD 2019年第8期78-85,共8页
Mixing of freshwater and seawater creates the well-known salinity gradients along the estuaries. In order to investigate how phytoplankton respond to the acute salinity changes, we exposed natural phytoplankton assemb... Mixing of freshwater and seawater creates the well-known salinity gradients along the estuaries. In order to investigate how phytoplankton respond to the acute salinity changes, we exposed natural phytoplankton assemblies from the Jiulong River Estuary to differential saline field water while continuously monitoring their photosynthetic performances under both indoor-and outdoor-growth conditions. When the natural cell assemblies from salinity 30 field water were exposed to series low saline field water(salinity 25, 17, 13 and 7.5), the effective Photosystem II quantum yield(ΔF/Fm′) decreased sharply, e.g., to one-fifth of its initials after 5 min exposure to salinity 7.5 field water, and then increased fast during the following 40 min and almost completely recovered after 320 min. During such an exposure process, non-photochemical quenching(NPQ) sharply increased from 0 to 0.85 within 5 min, and then decreased to nearly 0 within the following 70 min. When these cells re-acclimated to salinity 7.5 field water were exposed to series high saline field water(salinity 13, 17, 25 and 30), a similar response pattern was observed, with the decreased ΔF/Fm′ accompanied with increased NPQ, and followed by the recovery-induced increase in ΔF/Fm′ and decrease in NPQ. A similar response pattern as ΔF/Fm′to the acute osmotic stress was also observed in the photosynthetic carbon fixation capacity according to radiocarbon(14C) incorporation. Our results indicate that estuarine phytoplankton assemblies could rapidly recover from the acute osmotic stress, implying a potential cause for their frequent blooms in coastal-estuarine waters where despite drastically varying salinity, available nutrients are abundant due to the land-derived runoffs or mixing-caused relaxations from sediments. 展开更多
关键词 PSII quantum yield carbon fixation SALINITY gradients PHYTOPLANKTON ASSEMBLIES Jiulong River ESTUARY
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咸潮入侵对河口和河口型水库产生的影响 预览
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作者 陈蕾 赵欣 +1 位作者 张薇薇 彭程 《净水技术》 CAS 2019年第A01期34-37,共4页
咸潮入侵多发生在沿海地区,尤其是河口区域,在世界范围内均有发生。气候变化和人为活动可增加其发生的频率以及危害。河川径流和潮汐对于调节咸水在河口的时间分布和空间分布起着重要作用。在枯水季节,风力的变化显著地影响咸潮入侵。... 咸潮入侵多发生在沿海地区,尤其是河口区域,在世界范围内均有发生。气候变化和人为活动可增加其发生的频率以及危害。河川径流和潮汐对于调节咸水在河口的时间分布和空间分布起着重要作用。在枯水季节,风力的变化显著地影响咸潮入侵。咸潮入侵对饮用水,包括工业、农业生产用水,带来了一系列的危害。文中介绍了咸潮入侵对水环境和水生生物的影响、河口面临的蓝藻水华风险以及河口型水库所面临的挑战。 展开更多
关键词 咸潮入侵 河口 河口型水库
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大凌河与辽河入海口沉积物黏土矿物组成研究 预览
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作者 刘大为 刘兴宝 +1 位作者 胡克 刘洪顺 《海洋学报》 CAS CSCD 北大核心 2019年第2期75-84,共10页
采用X射线物相分析,对大凌河和辽河13个表层沉积物样品和4个柱状样中168个现代沉积物样品的主要黏土矿物含量组成进行分析。研究结果表明:大凌河沉积物黏土矿物组合为蒙脱石-伊利石-高岭石-绿泥石,辽河沉积物黏土矿物组合为伊利石-蒙脱... 采用X射线物相分析,对大凌河和辽河13个表层沉积物样品和4个柱状样中168个现代沉积物样品的主要黏土矿物含量组成进行分析。研究结果表明:大凌河沉积物黏土矿物组合为蒙脱石-伊利石-高岭石-绿泥石,辽河沉积物黏土矿物组合为伊利石-蒙脱石-绿泥石-高岭石。大凌河沉积物中蒙脱石与伊利石百分含量比值多大于1,而辽河沉积物该比值都小于1,且通过ISKc端元图能较清晰地区分两类沉积物,黏土矿物可以作为两条河流沉积物的判别标志。大凌河流域和辽河流域均以物理风化为主,辽河流域物理风化略强。流域内地质背景和气候条件等因素的差异造成了两条河流沉积物黏土矿物组成的不同。 展开更多
关键词 黏土矿物 河口 大凌河 辽河 判别标志
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