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1.
渤海与环渤海地区年降水量的统计分析   总被引:5,自引:1,他引:4  
李宁  刘珍  顾卫 《地理研究》2006,25(6):1022-1030
本文以渤海海域及环渤海地区分水岭内为研究区域,利用环渤海地区分水岭内92个气象站点自1971年至2000年30年的降水量资料,基于ARC/INFO地理信息系统支持下的泰森多边形法,对研究区域内的平均年降水量进行了统计分析。结论如下:环渤海地区分水岭以内区域的平均年降水量占整个环渤海地区2000年降水量的63.88%;渤海海域海水直接利用量占该海域平均年降水量的8.82%,其中辽东湾的海水利用量占该湾平均年降水量的3.09%,渤海湾为15.86%,莱州湾为17.38%;辽东湾2002年的海冰资源量占该湾平均年降水量的6.08%。在渤海海域水量平衡的关系研究中,本研究是初步的,基础的。划出分水岭内的研究区域进行平均年降水量的统计较对整个环渤海地区进行统计更具精确性。  相似文献   

2.
渤海风驱-潮致拉格朗日余流的数值模拟与季相时空变异   总被引:5,自引:0,他引:5  
利用HellermanandRosenstein全球风应力资料中的多年月平均风场资料驱动ECOM模型,设计了潮致、纯风生以及风与潮两者叠加三个数值实验对渤海海域风驱-潮致拉格朗日(Lagrange)余流的逐月时空分布与季节变化进行了模拟。研究结果表明,季风的大小和方向决定了渤海风驱-潮致拉格朗日余流的大小和方向,是影响余流流向和流速的重要因素。冬季,从渤海西岸到莱州湾海域风驱-潮致拉格朗日余流表现出一个大逆时针环流,辽东湾呈现顺时针方向流动,渤海中部存在一个弱的顺时针流环。夏季,整个渤海海域呈现顺时针流况,渤海海盆存在一微弱的逆时针涡旋,一支西南向流沿辽东湾东岸穿越渤海海盆,与起自渤海湾的东向流一起进入莱州湾。风驱-潮致拉格朗日余流主要受风的控制,潮汐则起到一定的调整作用。  相似文献   

3.
辽河流域社会经济活动的COD污染负荷   总被引:6,自引:1,他引:5  
王辉  栾维新  康敏捷 《地理研究》2013,32(10):1802-1813
辽河流域污染物的输入是辽东湾海洋环境变化的最主要原因,治理海洋污染的根本在于治理陆域污染。以辽河流域COD污染为研究对象,在社会经济数据空间化及与土地利用数据匹配的基础上剔除了部分无效数据,提高了流域污染物估算和空间分析的精度,估算结果表明:2010年辽河流域COD总污染负荷约101万t,其中居民生活和畜禽养殖排放合计占总污染负荷的80%,是流域COD污染的主要来源;工业源污染占11%;城市径流污染占9%。COD污染主要分布在辽河平原,且以面源污染为主,约有30万t入河。生物体代谢是COD污染的主要来源,污染物排放总量难于降低,辽河流域的COD污染压力短期内依然严峻。  相似文献   

4.
海岸带是人类活动的集中区和环境变化的敏感区,受气候变化与人类活动因素的影响,其环境和生态极易遭受扰动而恶化。改革开放以来,随着我国东部沿海地区工业化、城市化的迅速发展,海岸带陆源污染问题日益突出,已对该区域的环境质量和生态安全构成了严重威胁。非点源污染是海岸带河口及近海水体陆源污染的重要方面,在很多区域,非点源污染甚至已超过点源污染而成为河口和近岸海域水体污染的主要原因,在这种背景下,加强海岸带陆源非点源污染研究,意义非常重大。本文在概述非点源污染基本特征及其国内外研究现状的基础上,重点阐述了海岸带陆源非点源污染的研究进展,并指出了研究的不足之处,进而,提出了当前及未来时期需重点研究的内容以及需要注意的问题。  相似文献   

5.
基于SWAT模型的梅江流域非点源污染时空分布特征   总被引:1,自引:0,他引:1  
利用SWAT模型对亚热带季风湿润区红壤背景下江西省梅江流域非点源污染进行了模拟,并根据实测数据对模型的参数进行了率定和验证。在确定模型适用性的基础上,进行氮、磷营养盐负荷计算,分析了流域非点源污染负荷时空分布特征。结果表明:研究区非点源污染负荷具有显著的时空分布特征,在时间变化上,氮、磷污染负荷与降雨有明显相关性,R2分别是0.909和0.921;硝态氮年平均污染物负荷排放方式主要以下渗为主,下渗硝态氮排放量占总量的63%,与流域内高植被覆盖率有关;在空间分布上,有机氮与有机磷空间分布基本一致,流域内污染物主要分布在梅江中下游的黄陂河与会同河流域,不同土地利用下非点源污染负荷以耕地排放量为主。  相似文献   

6.
滹沱河流域本底状态地表水氮、磷非点源污染评价   总被引:2,自引:0,他引:2  
通过对滹沱河流域各支流源头区地表水中氮、磷浓度监测分析,得出本底状态下总氮浓度为0.223~5.631 mg/L,氨氮浓度范围为未检出~0.634 mg/L,可溶态氮浓度为0.190~5.532 mg/L,总磷浓度为0.024~0.683 mg/L,可溶态磷浓度为0.026~0.220 mg/L.本底状态下各水文期氮的非点源污染形态都以可溶态氮为主;磷的非点源污染形态枯水期以可溶态磷居多,丰水期以颗粒态磷为主.滹沱河流域本底状态下氮、磷非点源污染水平较高.  相似文献   

7.
太湖流域的水环境质量呈现严重恶化趋势,农业污染物的排放是太湖流域水体环境恶化的主要原因之一。农业污染物主要来源于种植业、畜禽养殖业和水产养殖业的生产过程,不同于以往分开论述三者对水环境的影响,本文基于全国第一次污染普查数据,运用污染足迹模型定量分析了湖州市农业面源(种植业、畜禽养殖业和水产养殖业)对水环境的影响。研究结果表明:(1)农业生产产生的污染物对水环境的影响排序为:磷>氮>有机物;(2)各农业生产类型对水环境的影响排序为:水产养殖业>种植业>畜禽养殖业;(3)湖州市各区县对水环境的影响也存在着明显的空间差异。通过对湖州市农业污染足迹评估,可以明确地提出哪种污染物类型、农业生产类型和区域是湖州市农业面源污染治理的重点。研究结果可以为太湖流域农业的可持续发展和水资源的可持续利用提供一定的参考价值。  相似文献   

8.
借助地理信息系统对闽江福州段进行流域划分,通过污染源数据的调查和分析,在流域层面上进行了污染负荷研究.研究以COD、NH3-N为主要指标,计算各子流域污染负荷,并确定其主要来源和比例关系.结果表明:闽江流域福州段COD入河总量为9371.75t,NH3-N入河总量为992.63t,工业源与城镇生活源是主要污染源.市区内...  相似文献   

9.
农业集聚的环境效应相比其他产业更为复杂,然而学术界对此探讨较少。在理论分析的基础上,利用2007—2015年中国337个地级市面板数据,核算农业集聚水平与农业面源污染排放量,并采用空间分析技术、计量模型,实证探究农业集聚与农业面源污染的时空特征及农业集聚对农业面源污染的门槛效应。结果显示:① 农业集聚与COD、TN、TP三种农业面源污染在时序变化、空间布局、空间关联以及空间趋势变化上特征相异。② 农业集聚对COD、TN、TP农业面源污染皆呈现正相关的单门槛效应。低于门槛值阶段,农业集聚水平的提高显著加剧了农业污染,集聚水平跨过门槛值后,污染加剧形势有所缓和。③ 农业集聚与农业面源污染之间经历的两个阶段,取决于规模效应、结构效应、技术效应、社会效应、累积效应分别对农业面源污染排放的加剧与制约作用。随着农业集聚水平提高,各效应增污作用明显,导致污染水平显著提高,进入高于门槛值的阶段,各效应对污染排放的抑制能力提升,削弱了部分负环境外部效应。④ 农业经济水平、农业生产条件在一定程度上加剧了COD、TN、TP污染;畜牧业结构、环境规制对COD、TP污染存在显著的正相关关系;生产者素质的提高可以影响农户生产行为并改善农业环境。⑤ 农业集聚对COD污染的降污效应较弱,农业COD污染较为严重且主要来源于畜牧业养殖,畜牧业污染防治亟待加强。  相似文献   

10.
菲尔德斯半岛南部邻近海域石油污染的初步研究   总被引:2,自引:0,他引:2       下载免费PDF全文
本文首次报道了菲尔德斯半岛南部邻近海域的水样和生物样石油污染状况。表层水样的测定结果表明 ,调查海域已受到明显的石油污染。在所调查的各站位 ,中国长城站前海湾受油污最轻 ,水样油的浓度略高于中国《海水水质标准》规定的第三类水质最高容许浓度 ,为 5 1 2 .2 5 μg/L;智利站前和海豹湾受油污最重 ,分别达 41 49.2 3 μg/L和 41 6 9.72 μg/L,约比长城站前海水含量高 8倍。几种海洋生物受污染程度不一 ,潮间带生物受油污明显高于鱼类。鉴于调查海域已受到明显的油污染 ,且进入南极水域后消除不易 ,为保护南极生态环境 ,很有必要开展油的净化规律 ,以及石油污染对生态系统影响等的研究。  相似文献   

11.
The loess mounds are a newly discovered type of landforms on the Laizhou Bay plain south of the Bohai Sea. Research shows that they were formed in the late period of the late Pleistocene when the Bohai Sea was exposed in the period of late Wümu glacial age and changed into plain. As the exposed area is not protected by vegetation, the sediments at the sea bottom are blown and transported southward by strong north winds, and deposit on the coastal plains. As thick loess is accumulated, the loess mound landforms are formed in the direction of down wind.  相似文献   

12.
Loess mounds are made of gray-yellow loess materials and the number is over 200 in the area of over 1000 km2 on the alluvial or marine-built plains south of Laizhou Bay (Figure 1). 1 The formal and distributional characteristics of loess mounds 1.1 Formal characteristics The plane forms of loess mounds are irregular oval or round. Their major axes are in north-south trending, most of them are 300 to 500 m long, with smaller ones tens m long, and individual larger ones more than 1,000 m …  相似文献   

13.
渤海莱州湾南岸平原黄土阜地貌及其古地理意义   总被引:16,自引:0,他引:16  
张祖陆 《地理学报》1995,50(5):464-470,T001
在莱州湾南岸滨海平原上发现一种新地貌类型黄土阜。研究表明,它形成于晚更新世晚玉木冰期。在此寒冷时期,渤海曾水退为平原,由于极少植被覆盖,形成陆架荒漠。裸露的海底松散沉积物被强劲的北风向南吹扬搬运,于南岸平原有利地形位置上沉积下来,形成厚层砂质黄土,并顺风向形成了阜状黄土地貌。  相似文献   

14.
本文以z坐标下的三维斜压海洋动力学数值模式为基本模式原型,在整理渤海基本数据并诊断计算风生环流和热盐环流作为背景环流场基础上,初步建立了渤海海域动力环境数值模式。模式采用了经校正的Bagnold型方程来计算渤海底移质沉积物输运,悬移质计算则是取二维深度平均悬移质输运方程和河床变形方程,计算含沙量分布以及由悬移物引起的冲淤厚度。利用这种方法建立的沉积物输运模式,定量模拟了渤海沿岸和海底的沉积物输运方向和冲淤分布。模拟结果与通过多年实测水深估算获得的渤海海底沉积物的冲淤变化分布相比较,两者之间在基本结论上是比较一致的  相似文献   

15.
海洋悬浮泥沙二元特征参数 MODIS遥感反演模型研究   总被引:1,自引:0,他引:1  
王芳  李国胜 《地理研究》2007,26(6):1186-1196
本文提出了一种采用海面离水辐射率和泥沙粒径二元特征参数来反演研究海区(渤海)海洋表层悬浮泥沙浓度的新的遥感反演算法,以此为基础分别建立了基于MODIS遥感数据和泥沙粒径二元特征参数的主成分和神经网络两种泥沙浓度反演模型,并对比分析了两类模型的反演精度以及泥沙粒径因子对模型的影响。分析结果表明,新建立的二元特征参数反演算法在采用主成分模型和神经网络模型时的检验误差分别为0.256和0.244,而忽略泥沙粒径因子贡献的主成分模型和神经网络模型的检验误差分别为0.384和0.390,因此可以认为,在泥沙浓度反演模型中加入粒径因子时,模型的预测精度和模型稳定性均比只考虑浓度对反射率贡献的模型有显著改善。  相似文献   

16.
The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the pa-laeoenvironment evolution. Systematic analyses of pollen, foraminifera and grain size com-position based on 14C and luminescence dating from two sediment cores were performed for the purpose of understanding the salt-water intrusion in the coastal plain of Laizhou Bay from the perspective of environmental evolution since late Pleistocene. It could be classified into seven evolution stages since 120 kaBP: 120–85 kaBP was a transition period from cold to warm; 85–76 kaBP was a period with warm and wet climate having swamp lakes developed in the lower reaches of the Weihe River, south coastal plain of Laizhou Bay; 76–50 kaBP was characterized by grassland vegetation and coarse sediments in terrestrial environment, which was the early stage of Dali Ice-Age; 50–24 kaBP was a period with alternate sea deposition in the south coastal plain of Laizhou Bay; 24–10 kaBP was the late stage of Dali Ice-Age with coldest period of Quaternary, the south coastal plain of Laizhou Bay was dry grassland and loess deposition environment; 10–4 kaBP was another warm and wet climate period, sea level was high and regressed at 4 kaBP; and has been the modern sedimentary environment since 4 kaBP. Among the three warm stages, including 85–76 kaBP, 50–24 kaBP and 10–4 kaBP, corresponded to late Yangkou, Guangrao and Kenli seawater transgression respec-tively. The duration of the latter one in south coastal plain of Laizhou Bay was longer than that in west coast of Bohai Sea and east coast of Laizhou Bay. The three periods of seawater transgression formed the foundation of salt-water intrusion in this area.  相似文献   

17.
The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the palaeoenvironment evolution. Systematic analyses of pollen, foraminifera and grain size composition based on ^14C and luminescence dating from two sediment cores were performed for the purpose of understanding the salt-water intrusion in the coastal plain of Laizhou Bay from the perspective of environmental evolution since late Pleistocene. It could be classified into seven evolution stages since 120 kaBP: 120-85 kaBP was a transition period from cold to warm; 85-76 kaBP was a period with warm and wet climate having swamp lakes developed in the lower reaches of the Weihe River, south coastal plain of Laizhou Bay; 76-50 kaBP was characterized by grassland vegetation and coarse sediments in terrestrial environment, which was the early stage of Dali Ice-Age; 50-24 kaBP was a period with alternate sea deposition in the south coastal plain of Laizhou Bay; 24-10 kaBP was the late stage of Dali Ice-Age with coldest period of Quaternary, the south coastal plain of Laizhou Bay was dry grassland and loess deposition environment; 10-4 kaBP was another warm and wet climate period, sea level was high and regressed at 4 kaBP; and has been the modern sedimentary environment since 4 kaBP. Among the three warm stages, including 85-76 kaBP, 50-24 kaBP and 10-4 kaBP, corresponded to late Yangkou, Guangrao and Kenli seawater transgression respectively. The duration of the latter one in south coastal plain of Laizhou Bay was longer than that in west coast of Bohai Sea and east coast of Laizhou Bay. The three periods of seawater transgression formed the foundation of salt-water intrusion in this area.  相似文献   

18.
In recent years, with the rapid development of China’s economy, the coastal environment is facing large pressure. However, the coastal environment pollution has not attracted much attention as air pollution and land water pollution. Based on the data on economic development and marine ecosystem environmental pollution which collected from the National Bureau of Statistics and China’s coastal marine environmental monitoring, the paper analyzes the overall coastal ecosystem environment pollution in China as well as the four sea areas the Bohai Sea, the Yellow Sea, the East China Sea and South China Sea. The paper finds that the coastal marine environment pollution differ in different sea areas, taking the seawater quality, over-standard pollutants, water quality of rivers entering seas and coastal marine environmental disasters, such as red tide as index. Couple of policy suggestions provided based on research findings.  相似文献   

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