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莱州湾南岸滨海湿地变化及其原因分析 总被引:3,自引:0,他引:3
以1992年和2004年的TM遥感影像为数据源,从景观生态学角度,对1992年和2004年的莱州湾南岸湿地及其变化进行了研究。结果表明,与1992年相比,2004年研究区湿地面积减少了32.339km2,其中,自然湿地面积减少了246.189km2,而人工湿地面积却增加了213.851km2,至2004年,人工湿地面积已占研究区湿地总面积的78.22%;湿地景观多样性指数下降了0.1077,景观优势度指数和景观破碎化指数分别上升至0.109和0.0089。自然湿地被大面积垦殖,湿地淡水资源不足,大规模开采沿海卤水资源,环境污染加剧,风暴潮等自然灾害频发,是导致研究区自然湿地萎缩的主要因素。 相似文献
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莱州湾南岸咸水入侵区土地利用/覆被变化驱动机理研究 总被引:2,自引:5,他引:2
借助于典型自相关模型分析,将众多变量归纳为少数几个综合变量,并分别就这些综合变量进行系统阐述。影响研究区土地利用变化的社会经济因素可以归纳为:人口增长、产业结构调整、工业发展与城镇化等综合指标,并分别对各不同影响因素进行阐述。在自然因素方面,咸水入侵与土地利用结构特征及其变化方向具有相关性,它是可以综合反映自然驱动因素的代表性因子。 相似文献
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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
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
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基于ArcGIS10.3平台对莱州湾南岸中全新世聚落遗址的高程、坡度、坡向、濒河度等指标进行分析,得出该时期聚落遗址的时空分布及演变特征,并结合全新世莱州湾南岸的环境背景,探讨全新世环境演变对聚落遗址分布及演变的影响。研究表明:① 全新世莱州湾南岸的聚落遗址数量、出现频率及在总数中的比重基本呈现明显的先增后降的倒V型(非对称)变化趋势。② 遗址高程分布具有一定的规律性,几乎所有时期的遗址点均分布于高程范围在0~29 m的地区,而大汶口文化时期遗址高程分布范围为10~29 m。从坡度来看,聚落遗址主要分布于坡度范围在0~4°的平缓地区;从坡向来看,古人大多集中在南向、东南向和西南向的位置。后李文化至龙山文化时期,河流对聚落选址的影响程度逐渐降低。③ 8.5~6.9 ka B.P.气候总体进入温暖期,且冷暖波动,干湿交替,后李文化由此得到发展;6.9~4.5 ka B.P.出现了短暂的降温,但整体较温和,优越的自然条件促进了大汶口文化的发展;4.5~4.0 ka B.P.左右气候条件较大汶口文化时期略干,但在此基础上新石器文化仍得到进一步发展,并于龙山文化时期进入鼎盛阶段;4.0 ka B.P.左右气候突变,出现剧烈降温事件,变化幅度超出了人类的适应能力,岳石文化随之衰落。④ 海水入侵限制了人类活动,而古湖泊和古河道的形成为古人生活质量的提高创造了天然条件。 相似文献
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莱州湾南岸咸水入侵区晚更新世以来的古环境演变 总被引:8,自引:0,他引:8
莱州湾南岸是我国典型的咸水入侵区,古环境变化构成了现代咸水入侵发生的背景。本文通过对潍河下游地区A1、A5孔岩芯系统的孢粉、有孔虫、粒度、14C及热释光测年资料的分析,结合100余个钻孔的沉积特征,论述了莱州湾南岸地区晚更新世以来的古环境演化特征。本区经历了三次明显的冷暖气候波动,三次显著的暖湿期为85~76kaBP、50~24kaBP、10~4kaBP,为海陆过渡相沉积环境,这三个时期分别与晚更新以来的三次海侵相对应,与相邻区域相比,全新世海侵开始早、结束晚;两次冷干期为76~50kaBP、24~10kaBP,分别对应于早大理冰期、晚大理冰期,为陆相沉积环境。 相似文献
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莱州湾南岸湿地水文环境变化与可持续的水资源管理对策 总被引:1,自引:3,他引:1
水文环境变化能影响滨海湿地生态系统的结构和功能。受气候干旱、河流断流、陆源污染物输入、地下咸-卤水入侵以及各种海洋灾害日益加剧等因素的影响,最近30多年来莱州湾南岸滨海湿地严重退化,表现为历史时期形成的淡水湖泊湿地现在大都已经退化消失,大面积的潮上带自然湿地被虾蟹池、盐田等人工湿地取代,潮间带湿地底质和潮下带湿地水质不断恶化,赤潮等海洋灾害多发,湿地生物多样性受损,渔业资源衰退等。针对导致湿地退化的原因,提出了提高水资源利用效率和节约利用淡水资源,加强水环境整治与保护,严格控制污染物入海减轻对湿地的污染,实施跨流域调水工程来增加湿地蓄水量以满足湿地生态需水,减轻海洋灾害等恢复和重建退化湿地的水资源可持续管理对策。 相似文献
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渤海莱州湾南岸潍河-弥河三角洲:沉积序列和沉积格架 总被引:7,自引:2,他引:7
潍河-弥河三角洲是一个由多条河流共同塑造的三角洲。前三角洲黏土质粉砂是各河流共同贡献的结果;每条河口之外形成各自的三角洲前缘,主要由极细砂组成;河口间湾沉积物是两条相邻河流共同塑造的,主要为黏土质粉砂。由于河口位置的侧向摆动,三角洲前缘极细砂和河口间湾黏土质粉砂会交替出现。7000a B. P. 以来向海进积20~55km,在海岸附近三角州沉积物厚度超过20m。 相似文献
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历史时期莱州湾沿海平原湖沼的变迁* 总被引:6,自引:1,他引:6
莱州湾沿海平原地区,古代曾有许多湖沼,其中以巨淀湖最大。根据历史文献和考古资料,查明了随着历史的发展,巨淀湖发生空间转移,并查明大部分湖沼最后逐渐消失的过程,阐述了这些湖沼空间分布特点以及导致变迁的因素,探讨它们消失的环境后果,并尝试提出吸取历史教训改善环境的建议。 相似文献
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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
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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
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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
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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
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吴忱 《地理与地理信息科学》2008,24(3):83-86
华北平原地下埋深30~50 m以上分布着众多古河道。它是开采浅层地下淡水的源泉,"三水"调蓄转化的库容,旱、涝、碱、咸灾害综合治理的场所,农业综合开发的宝地,农田水利布设的基础,地震时沙基液化和震害的严重区。论述华北平原古河道开发利用取得的经济效益,提出开发利用中面临的新问题及对策。 相似文献
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杭州湾南岸生态系统服务功能及其经济价值研究 总被引:16,自引:2,他引:16
生态系统服务功能是生态系统提供的商品和服务,是人类生存发展的物质基础和基本条件。该文应用生态学、生态经济学方法及Costanza功等的研究成果,结合杭州湾南岸生态系统的自然和社会经济特征的分析,初步估算出2000年杭州湾南岸生态系统服务功能的总价值为91.1亿元,其中间接经济价值是直接经济价值的5.85倍,并对各种生态系统类型的服务价值构成进行了讨论。 相似文献