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珠江口虎门水域洪季大潮的水沙特点分析 被引量:11
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作者 尹小玲 张红武 +1 位作者 任杰 胡德超 《水利学报》 EI CSCD 北大核心 2009年第2期166-172,共7页
2004年洪季大、中潮期间,用声学多普勒流速剖面仪(ADP)和传统观测方法对珠江口虎门水域水流、悬沙浓度及底质粒度进行了现场多点同步观测。本文基于观测资料,分析总结了该地区水流、泥沙运动特点及河床演变规律。结果表明,虎门口潮汐水... 2004年洪季大、中潮期间,用声学多普勒流速剖面仪(ADP)和传统观测方法对珠江口虎门水域水流、悬沙浓度及底质粒度进行了现场多点同步观测。本文基于观测资料,分析总结了该地区水流、泥沙运动特点及河床演变规律。结果表明,虎门口潮汐水流的特点有利于保持伶仃洋交椅湾和东滩的缓慢淤积速度;洪季凫洲水道的水流过程对虎门深槽影响较小,上游来沙易于通过虎门口向外输移,但对鸡抱沙围垦区东北角有冲刷影响,同时对舢板洲一侧有淤积压力。 展开更多
关键词 虎门 珠江 洪季 潮汐水流 ADP 泥沙输移 河床演变
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洪季长江口径流量与近海海平面的响应关系 被引量:4
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作者 匡翠萍 陈维 +1 位作者 顾杰 贺露露 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2015年第8期1266-1272,共7页
为了分析长江口洪季径流量对其近海海平面上升的影响权重,基于1950~2011年大通站实测洪季月均径流量资料,统计分析出大通站洪季发生频率为25%,50%和75%时对应的径流量以及多年平均径流量,并利用长江口杭州湾潮流数学模型,计算分析长江... 为了分析长江口洪季径流量对其近海海平面上升的影响权重,基于1950~2011年大通站实测洪季月均径流量资料,统计分析出大通站洪季发生频率为25%,50%和75%时对应的径流量以及多年平均径流量,并利用长江口杭州湾潮流数学模型,计算分析长江洪季径流量对长江口口内平均潮位和近海海平面的影响.研究结果表明:随着径流量的增加,整个计算区域的平均潮位也随之增大,且从上游到口外平均潮位增幅沿程减小,近海南部平均潮位增长幅度比近海北部大.口内及近海平均潮位与径流量呈正相关关系,在径流量增加20 000m3·s-1的情况下,杭州湾大部分区域平均潮位增加0.005~0.010m. 展开更多
关键词 长江口 径流量 MIKE 21软件 海平面 洪季
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人类活动驱动下伶仃洋洪季大潮水沙异变 被引量:9
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作者 谢丽莉 刘霞 +1 位作者 杨清书 黄广灵 《泥沙研究》 CSCD 北大核心 2015年第3期56-62,共7页
针对大规模人类活动对伶仃洋水动力的干预,基于1978年、2003年、2011年洪季大潮实测资料,对比分析伶仃洋东西两槽及东四口门在不同阶段人类活动作用下的潮流及悬沙特征变化。结果表明:由于受伶仃水道浚深影响,与1978年相比,2003年和201... 针对大规模人类活动对伶仃洋水动力的干预,基于1978年、2003年、2011年洪季大潮实测资料,对比分析伶仃洋东西两槽及东四口门在不同阶段人类活动作用下的潮流及悬沙特征变化。结果表明:由于受伶仃水道浚深影响,与1978年相比,2003年和2011年伶仃水道及东四口门洪季大潮的涨潮动力增强,落潮动力减弱;受伶仃水道浚深产生的"吸流"作用及东滩围垦影响,矾石水道潮流动力减弱;东四口门及矾石水道洪季大潮的悬沙含量降低,伶仃水道悬沙垂向分层加强,且伶仃水道中南段净输沙由1978年的向海方向于2003年后逆转变为向陆方向,平均流输沙贡献剧减,斯托克斯漂流输沙、潮汐捕集输沙和垂向净环流输沙贡献增加。 展开更多
关键词 伶仃洋 洪季大潮 水沙动力 悬沙输移机制 人类活动
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赣江尾闾河网地形变化对洪季水动力的影响 被引量:4
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作者 白玉川 李晓文 +1 位作者 徐海珏 宋晓龙 《水力发电学报》 CSCD 北大核心 2022年第3期9-21,共13页
为探明在新水沙条件和人类活动的影响下赣江尾闾河网地形变化与洪季水动力特征变化的关系,以1998—2020年为研究时段,基于1998、2013、2020年河道地形,分别建立一维河网数学模型,复演赣江98特大洪水,研究不同时期地形变化对洪季水动力... 为探明在新水沙条件和人类活动的影响下赣江尾闾河网地形变化与洪季水动力特征变化的关系,以1998—2020年为研究时段,基于1998、2013、2020年河道地形,分别建立一维河网数学模型,复演赣江98特大洪水,研究不同时期地形变化对洪季水动力特征的影响。结果表明:赣江尾闾河网的整体下切使水位流量关系右移,洪期各支洪峰流量整体增加,相同水位下,外洲站来流增幅超过50%。1998—2020年期间,南支地形下切幅度大于其他各支,地形不均匀下切导致尾闾河网节点分流比改变,整体上主支与南支分流增多、中支与北支分流减少。各支流速变化剧烈,主支下游流速增幅超过1 m/s。本研究可为河道整治规划、堤坝防护和灾害预防提供一些技术参考。 展开更多
关键词 水动力 洪季 一维河网 赣江尾闾
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长江口南港河段洪季水质评价 被引量:2
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作者 吴国元 余国培 +1 位作者 王中远 陈景山 《海洋环境科学》 CAS CSCD 北大核心 1990年第1期28-34,共7页
根据1985年7—8月长江洪水季节水质监测资料,运用评分法和隶属度法,对长江口南港河段水质作出了单项评价和综合评价。水质评价项目共12项,水质评价标准基本依据“上海市地面水环境质量分级标准”。综合评价结果表明,该河段水质大部分为... 根据1985年7—8月长江洪水季节水质监测资料,运用评分法和隶属度法,对长江口南港河段水质作出了单项评价和综合评价。水质评价项目共12项,水质评价标准基本依据“上海市地面水环境质量分级标准”。综合评价结果表明,该河段水质大部分为二级和三级,较客观地反映了实际情况。本文为实现上海城市污水向长江口外排提供了必要的科学依据。 展开更多
关键词 长江口 南港河段 洪季 水质评价
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珠江三角洲近年地形不均匀变化对洪季水动力特征的影响 被引量:13
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作者 陈小齐 余明辉 +2 位作者 刘长杰 田浩永 刘画眉 《水科学进展》 EI CAS CSCD 北大核心 2020年第1期81-90,共10页
为探明在新水沙条件和人类活动的影响下珠江三角洲河网地形变化与洪季水动力特征变化之间的关系,以1999-2008年为研究时段,基于1999年地形建立一维河网数学模型,复演珠江三角洲地区"08·6"洪水,并与"08·6"... 为探明在新水沙条件和人类活动的影响下珠江三角洲河网地形变化与洪季水动力特征变化之间的关系,以1999-2008年为研究时段,基于1999年地形建立一维河网数学模型,复演珠江三角洲地区"08·6"洪水,并与"08·6"实测资料进行对比,分析河网地形变化对洪季水动力特征的影响。结果表明:①珠江三角洲河网地形整体下切加强了河道行洪能力,在遭遇洪峰30年一遇的"08·6"洪水时洪水位整体下降,三角洲顶部马口站洪水位最大降幅达到0.9 m;②河网内潮差和潮汐传播速度增大,潮区界上移至马口、三水以上;③西江河网地形下切幅度大于北江河网,地形不均匀下切导致河网节点分流比改变,西江河网洪水期分流增加2%,马口站和天河站洪峰流量增幅分别接近1 500 m^3/s和1 000 m^3/s;④西江马口站分流比随上游洪水流量增大而减小的趋势没有改变,但地形不均匀下切导致其变化梯度增大。珠江三角洲近年地形的不均匀下切,是近年珠江三角洲河网地区,特别是河网腹地洪水灾害有所减轻的主要原因之一。 展开更多
关键词 水动力 洪季 人类活动 珠江三角洲
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长江口洪季南北槽落潮分流分沙比观测研究 被引量:3
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作者 杨万伦 道付海 +2 位作者 栾华龙 葛建忠 丁平兴 《华东师范大学学报(自然科学版)》 CAS CSCD 北大核心 2018年第2期170-180,共11页
基于2015年洪季水文观测资料,分析了长江口洪季北槽大小潮期间落潮分流和分沙特征,及其差异和原因.观测结果显示:北槽大潮和小潮落潮分流比均值分别为41.9%和43.1%,大潮和小潮落潮分沙比均值分别为35.1%和39.0%,大小潮差异较小,故大潮... 基于2015年洪季水文观测资料,分析了长江口洪季北槽大小潮期间落潮分流和分沙特征,及其差异和原因.观测结果显示:北槽大潮和小潮落潮分流比均值分别为41.9%和43.1%,大潮和小潮落潮分沙比均值分别为35.1%和39.0%,大小潮差异较小,故大潮落潮分沙情况可近似代表当月落潮分沙情况.大小潮期间北槽落潮分沙比与南北槽断面平均流速之比、断面平均含沙量之比和断面面积之比有关,而观测结果显示大小潮周期内南北槽断面面积比值、断面含沙量比值、断面流速比值均无较大差异.因此,大小潮北槽落潮分流和分沙情况差异不大. 展开更多
关键词 长江口 洪季 大小潮 落潮分沙比
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近30年珠江口内伶仃洋洪季最大浑浊带的变化特征 被引量:5
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作者 杨江平 刘文涛 《珠江水运》 2015年第16期58-62,共5页
利用广州海洋地质调查局2003年6月和2012年7月在珠江口内伶仃洋所获取的悬浮物浓度及地形地貌资料,结合历史相关研究成果等资料,分析了研究区最大浑浊带近30年以来洪季期间空间及形态上的长期发展与变化特征。结果显示,自1978年以来,内... 利用广州海洋地质调查局2003年6月和2012年7月在珠江口内伶仃洋所获取的悬浮物浓度及地形地貌资料,结合历史相关研究成果等资料,分析了研究区最大浑浊带近30年以来洪季期间空间及形态上的长期发展与变化特征。结果显示,自1978年以来,内伶仃洋海域最大浑浊带洪季表现出南段整体向南移且向东南扩进,而北段相对位置变化不大,浑浊带由呈NE-SW向延伸的连续状逐渐演变成多个独立的分布区。研究认为区域西岸河道不断延伸、岸线整体向东南逼进及局部径潮比增大是造成最大浑浊带不断发生变化的主要原因。 展开更多
关键词 内伶仃洋 最大浑浊带 洪季 变化特征
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长江口颗粒态金属污染物时空分布规律分析 被引量:5
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作者 刘启贞 李九发 +2 位作者 戴志军 赵建春 冯凌旋 《海洋环境科学》 CAS CSCD 北大核心 2009年第3期251-256,共6页
长江口金属污染物的输移转化受到多种因素作用的制约,其时空分布比较复杂。2006年洪、枯季长江口南槽和北槽调查研究表明:(1)悬沙中各种金属含量在长江口的沿程分布略有差异,除Cu、Cd沿程出现降低趋势外,其它金属均有"低-高-低&qu... 长江口金属污染物的输移转化受到多种因素作用的制约,其时空分布比较复杂。2006年洪、枯季长江口南槽和北槽调查研究表明:(1)悬沙中各种金属含量在长江口的沿程分布略有差异,除Cu、Cd沿程出现降低趋势外,其它金属均有"低-高-低"分布趋势,即在南槽、北槽最大浑浊带出现高值;而沉积物中颗粒态金属含量沿程分布较为复杂,沿程呈降低趋势,部分金属在南槽、北槽出现高值区;(2)颗粒态金属含量垂向分布十分明显,由表层悬沙至底泥逐渐减少;(3)悬沙中枯季金属含量明显高于洪季,在一个潮周期内急流时颗粒态金属含量小于憩流时金属含量。 展开更多
关键词 长江口 颗粒态金属 悬移质 底质 洪季 枯季
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闽江下游河流运动规律分析 被引量:9
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作者 杨首龙 《人民长江》 北大核心 2012年第S2期97-101,共5页
针对闽江下游天然河道的地形边界条件,探讨了洪、中、枯不同径流与闽江口天文大潮遭遇时河流流动规律,分析了关键河床断面的水位变化、流场变化以及潮流界、潮区界,从而揭示了洪、中、枯不同水流条件下福州南北港分流比的动态变化和南... 针对闽江下游天然河道的地形边界条件,探讨了洪、中、枯不同径流与闽江口天文大潮遭遇时河流流动规律,分析了关键河床断面的水位变化、流场变化以及潮流界、潮区界,从而揭示了洪、中、枯不同水流条件下福州南北港分流比的动态变化和南北港涨落潮相位变化的特点。闽江下游河流运动规律对省会城市福州正在进行的"东扩南进、沿江向海"城市发展战略的实施以及城市堤防安全、水源地取水口安全、滨海游艇产业发展具有重要意义。 展开更多
关键词 流动特性 洪季 枯季 中水 闽江下游河道
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长江澄通河段河床冲淤对流域减沙的响应 被引量:8
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作者 朱博渊 李义天 +3 位作者 杨培炎 邓金运 杨云平 李思璇 《水科学进展》 EI CAS CSCD 北大核心 2018年第5期706-716,共11页
为研究潮汐河道不同区段在流域来沙减少条件下的冲淤响应机制,以长江澄通河段为例,根据水动力特性将其划分为江阴—天生港和天生港—徐六泾两段,结合1950—2014年的水沙资料及2005—2014年的地形资料,比较两段冲淤对流域减沙的响应差异... 为研究潮汐河道不同区段在流域来沙减少条件下的冲淤响应机制,以长江澄通河段为例,根据水动力特性将其划分为江阴—天生港和天生港—徐六泾两段,结合1950—2014年的水沙资料及2005—2014年的地形资料,比较两段冲淤对流域减沙的响应差异。结果表明:上游江阴—天生港段对流域减沙敏感,较快地由淤积转为冲刷;下游天生港—徐六泾段1998—2004年期间受洪季平均径流流量减小、潮汐顶托作用相对增大的影响,冲刷速率为减小趋势,2004年以后受洪季平均径流流量增大、潮汐顶托作用相对减小及流域来沙持续减少的共同影响,冲刷速率为增大趋势。使得潮汐动力对天生港—徐六泾段由促淤变为促冲的临界洪季平均径流流量为36 000 m3/s,该径流流量也是使得潮汐顶托作用在江阴—天生港段由不显著变为显著的临界流量。目前,流域减沙已加剧澄通河段整体的冲刷。 展开更多
关键词 澄通河段 冲淤速率 沙量 洪季平均径流流量 潮汐
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Estimate of CH_4 Emissions from Year-Round Flooded Rice Fields During Rice Growing Season in China 被引量:99
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作者 CAIZu-Cong KANGGuo-Ding +1 位作者 H.TSURUTA A.MOSIER 《Pedosphere》 SCIE CAS CSCD 2005年第1期66-71,共6页
A special kind of rice field exists in China that is flooded year-round. These rice fields have substantially large CH4 emissions during the rice-growing season and emit CH4 continuously in the non-rice growing season... A special kind of rice field exists in China that is flooded year-round. These rice fields have substantially large CH4 emissions during the rice-growing season and emit CH4 continuously in the non-rice growing season. CH4 emission factors were used to estimate the CH4 emissions from year-round flooded rice fields during the rice-growing season in China. The CH4 emissions for the year-round flooded rice fields in China for the rice growing season over a total area of 2.66 Mha were estimated to be 2.44 Tg CH… 展开更多
关键词 IPCC methodology methane emission rice fields year-round flooded
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Extreme Rainfall Events and Associated Natural Hazards in Alaknanda Valley, Indian Himalayan Region 被引量:4
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作者 JOSHI Varun KUMAR Kireet 《Journal of Mountain Science》 SCIE CSCD 2006年第3期228-236,共9页
Entire Himalayan region is vulnerable to rain-induced (torrential rainfall) hazards in the form of flash flood, cloudburst or glacial lake outburst flood Flash floods and cloudburst are generally caused by high inte... Entire Himalayan region is vulnerable to rain-induced (torrential rainfall) hazards in the form of flash flood, cloudburst or glacial lake outburst flood Flash floods and cloudburst are generally caused by high intensity rainfall followed by debris flow or landslide often resulting into blockade of river channels. The examples of some major disasters caused by torrential rainfall events in last fifty years are the flash floods of 1968 in Teesta valley, in 1993 and 2000 in Sutlej valley, in 1978 in Bhagirathi and in 1970 in Alaknanda river valleys. The formation of landslide dams and subsequent breaching is also associated with such rainfall events. These dams may persist for years or may burst within a short span of its formation. Due to sudden surge of water level in the river valleys, havoc and panic are created in the down stream. In Maknanda valley, frequencies of such extreme rainfall events are found to be increasing in last two decades. However, the monthly trend of extreme rainfall events has partly indicated this increase. In most of the years extreme rainfall events and cloudburst disaster were reported in August during the later part of the monsoon season. 展开更多
关键词 Flash flood Cloudburst Extreme rainfall Alaknanda valley HIMALAYA INDIA
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Study on measures for water prevention and control in Chengchao Iron Mine,China
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作者 Zou Can Wu Li 《Engineering Sciences》 EI 2010年第3期85-89,共5页
The gush-out water in the mineral pit endangers the underground mine safety directly. It is an important task for underground mine to guarantee its safety during the flood season. The authors analyzed the status of wa... The gush-out water in the mineral pit endangers the underground mine safety directly. It is an important task for underground mine to guarantee its safety during the flood season. The authors analyzed the status of water prevention and control in Chengchao Iron Mine,China,and put forward the necessary measures. The hydrogeological parameter controls the design of mine water prevention and affects the mineral well safety in operation. Enhance supervision and control,keeping the current facilities intact,using the existing pump house and the underground tunnel to adjust and control the amount of water and improving the hydrogeological conditions in the mine are the practical and remedial measures. 展开更多
关键词 hydrogeological parameters flood control ability measures
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Inundation Calculation of the Coastal Narrow Plain Strip Impacted by Upstream Reservoir Flood Discharge in Rainy and Extreme Flood Conditions
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作者 Nguyen Ngoe Naml Le Van Nghi Bui Thi Ngan 《Journal of Shipping and Ocean Engineering》 2016年第3期165-178,共14页
In the context of current climate change, an abnormality of flooding is a common form of disaster in Vietnam. Hanh Stream reservoir has occurred great flood in 1986, 2010. In the future, the risk of flooding is possib... In the context of current climate change, an abnormality of flooding is a common form of disaster in Vietnam. Hanh Stream reservoir has occurred great flood in 1986, 2010. In the future, the risk of flooding is possible to happen again. In view of management of the risk of natural disasters: large flooding situation downstream is one of the most dangerous risks for the reservoir. Due to downstream of Hanh Stream reservoir is a narrow coastal plains, quick infrastructure development, especially interwoven road and railway systems, so that flood drainage ability will be affected greatly. The consciousness of risks that may be occurred in the future in order to propose preventive measures and proactive response to minimize damages always is the requirement for all projects. The hydrodynamic calculation, flooding maps, emergency plan to prevent flooding downstream of Hanh Stream reservoir is also needed. The article is raised the issue of requirements to calculate coastal narrow delta strip flooding in the Central of Vietnam when impacted by the upstream reservoir of flood discharge in terms of extreme heavy rain and flooding and presented computational methods of Mike software package for case flooded plain of Cam Ranh Bay in downstream reservoirs of Hanh Stream, Khanh Hoa Province, Vietnam. 展开更多
关键词 Reservoirs Hanh Stream maps INUNDATION narrow plain narrow delta coastal hydrodynamic calculation flood flooding.
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Water Security-based Hydrological Regime Assessment Method for Lakes with Extreme Seasonal Water Level Fluctuations:A Case Study of Poyang Lake,China 被引量:2
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作者 WAN Rongrong YANG Guishan +2 位作者 DAI Xue ZHANG Yanhui LI Bing 《Chinese Geographical Science》 SCIE CSCD 2018年第3期456-469,共14页
Extreme seasonal water level fluctuations characterize natural floodplain lakes in monsoon regions, which are crucial for ensuring lake water security, including flood prevention water supply and health of aquatic eco... Extreme seasonal water level fluctuations characterize natural floodplain lakes in monsoon regions, which are crucial for ensuring lake water security, including flood prevention water supply and health of aquatic ecosystem. In order to achieve this goal, we established a hydrological regime assessment method based on a set of hydrological indicators for lakes with heavy seasonal water level fluctuations. The results suggest that time-sensitive hydrological indicators and specific time scales for various water security aspects must be considered. We discovered that it is more practical and meaningful to combine the water level classification derived from statistical analyses with characteristic hydrological values linked to water security. The case study of Poyang Lake results show that there are no discernable trends of Poyang Lake water regime status over the last 35 years, and the two periods of poor status are in accordance with climate variation in the lake basin area. Scholars and policy makers should focus on both floods and droughts, which are the main water security problems for Poyang Lake. It is hoped that this multi-scale and multi-element hydrological regime assessment method will provide new guidelines and methods for other international scholars of river and lake water assessment. 展开更多
关键词 lake water regime assessment water security seasonal water level fluctuations natural lakes Poyang Lake
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CLIMATOLOGICAL CHARACTERISTICS FOR THE ONSET OF ASIAN SUMMER MONSOON AS REVEALED BY HIRS-Tb12 AND DROUGHT AND FLOODS IN EASTERN CHINA
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作者 施宁 蒋尚城 严明良 《Journal of Tropical Meteorology》 SCIE 2002年第2期141-149,共9页
As shown in comparison and study of the HIRS-Tb12 data and conventional data, temperature, humidity and vertical motion are structured differently in the Southern and Northern Hemispheres, which are well depicted with... As shown in comparison and study of the HIRS-Tb12 data and conventional data, temperature, humidity and vertical motion are structured differently in the Southern and Northern Hemispheres, which are well depicted with the HIRS-Tb12 data. When high pressures rapidly decrease over the regions of South China Sea and Arabian Sea with the HIRS-Tb12 less than 200 W/m2, monsoons will set off in the South China Sea, Arabian Sea and Bay of Bengal, respectively. From a year of significant drought to one of significant floods, the trend of evolution is significantly different in the downdraft areas of the subtropical highs between the two hemispheres. 展开更多
关键词 HIRS-Tb12 downdraft area of subtropical high Asian monsoons drought and floods in eastern China
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Bird Species Diversity and Spatio-temporal Variation in the Sihong Hongze Lake Wetland National Nature Reserve in Eastern China
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作者 HU Huali XIAO Lihui +3 位作者 ZHANG Manyu WANG Silu CHEN Taiyu LU Changhu 《Journal of Resources and Ecology》 CSCD 2024年第4期826-837,共12页
As an important hub on the East Asian-Australian Flyway(EAAF),Hongze Lake is an important migratory stopover and wintering site for hundreds of thousands of birds.However,research on bird community diversity in this a... As an important hub on the East Asian-Australian Flyway(EAAF),Hongze Lake is an important migratory stopover and wintering site for hundreds of thousands of birds.However,research on bird community diversity in this area is still lacking.We conducted a bird survey from July 2020 to June 2021 using the line transect method on the terrestrial habitat,as well as the fixed-point method in the lake wetland at the Sihong Hongze Lake Wetland National Nature Reserve located in northwestern Hongze Lake,and analyzed the temporal-spatial variation in the bird community.The results showed that a total of 170432 detections of 215 bird species belonging to 18 orders and 55 families were recorded.In terms of species composition,the proportion of terrestrial birds was relatively high,followed by waterfowl richness,with high numbers of Anatidae species and shorebirds.For bird species abundance,waterfowl had the highest abundance of common coot(Fulica atra),belonging to the Rallidae family,followed by Anatidae and Ardeidae species.The abundance of shorebirds was extremely low,and that of non-waterfowl was also low.In terms of temporal patterns,the number of bird species and richness index were higher in spring and autumn but lower in winter and summer.The bird abundance was the highest in winter,and the remaining three seasons were similar in terms of bird abundance.The diversity index and evenness index were higher in spring,summer and autumn,and lowest in winter.For the spatial pattern,the open water in the western part of the reserve included the most densely distributed areas for birds,and the number of bird species and their abundance were both the highest in that part.There were significant differences in the bird community structures among the four habitats.The species number and richness index of birds in the reed habitat were the highest,and the bird abundance was also high,but the diversity index and evenness index were low.Although the bird abundance in the lake habitat was much higher than in the other habitats,the diversity index,evenness index and richness index were the lowest.The numbers of bird species and individuals in tourist attraction land and farmland were low,but the diversity index,evenness index and richness index were high.Our results reveal the spatial and temporal patterns of bird species diversity and abundance in Sihong Hongze Lake Wetland National Nature Reserve,and reflect the effects of different habitat types on bird diversity. 展开更多
关键词 bird diversity seasonal variation spatial distribution Sihong Hongze Lake Wetland National Nature Reserve
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Fluctuations in the tidal limit of the Yangtze River estuary in the last decade 被引量:3
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作者 Shengyu SHI Heqin CHENG +4 位作者 Xiaona XUAN Fangxi HU Xiaoting YUAN Yuehua JIANG Quanping ZHOU 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第8期1136-1147,共12页
The tidal limit is the key interface indicating whether water levels will be affected by tidal waves, which is of great significance to navigation safety and regional flood control. Due to limitations in research meth... The tidal limit is the key interface indicating whether water levels will be affected by tidal waves, which is of great significance to navigation safety and regional flood control. Due to limitations in research methods, recent changes in the Yangtze River tidal limit, caused by sea level rise and large-scale engineering projects, urgently need to be studied. In this study,spectrum analysis was undertaken on measured water level data from downstream Yangtze River hydrological stations from2007 to 2016. The bounds of the tidal limit were identified through comparisons between the spectra and red noise curves, and the fluctuation range and characteristics were summarized. The results showed that:(1) During the extremely dry period, when the flow rate at Jiujiang station was about 8440 m3 s-1, the tidal limit was near Jiujiang; whereas during the flood season, when the flow rate at Jiujiang station was about 66700 m3 s-1, the tidal limit was between Zongyang Sluice and Chikou station.(2)From the upper to lower reach, the effect of the Jiujiang flow rate on the tidal limit weakens, while the effect of the Nanjing tidal range increases. The tidal limit fluctuates under similar flow rates and tidal ranges, and the fluctuation range increases with increasing flow rate and decreasing tidal range.(3) With the continued influence of rising sea levels and construction in river basin estuaries, the tidal limit may move further upstream. 展开更多
关键词 YANGTZE River estuary Tidal limit Extreme flow Fluctuation characteristics Spectrum analysis
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