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1.
本文在总结长江口地区现状盐水入侵时空变化规律的基础上,着重分析了在未来海平面上升、长江东线南水北调和三峡水利枢纽工程以及长江口北支综合整治等因素影响下,南支河段盐水入侵强度的变化趋势。 相似文献
2.
Jianhua Gao Guishan Yang Weixin Ou 《Frontiers of Environmental Science & Engineering》2008,2(1):81-88
In order to explore the effect of different ecological zones and their above plants in the organic matter cycling of the whole tidal salt marsh, indicators such as total organic carbon (TOC), total nitrogen (TN), C/N ratio, δ13C and δ15N of surface, core sediments, and plants of tidal salt marshes in North Jiangsu Province are analyzed. Subsequently, distribution regularities of these measurement indicators are discussed, and the biogeochemistry processes between sediments and plants are also analyzed. Lastly, the organic matter sources of different ecologic zones in tidal salt marsh are evaluated, and the organic matter accumulations in different ecologic zones induced by their plants are also compared. These results indicate that TOC, TN, C/N ratio and δ13C showed obvious zonal distribution. The organic matter sources are dominated by marine input in the silt flat, artemisia schrenkiana flat, and the transition zone between silt and spartina alterniflora flat, and are controlled by terrigenous input in spartina alterniflora flat. Spartina alterniflora plays an important role in the accumulation of organic matter in the whole tidal salt marshes ecosystem. In the study area, the annually increased TOC, organic matter and TN in the spartina alterniflora, artemisia schrenkiana and reed flats reach 6,451, 12,043 and 536 t, respectively. The amount of TOC, organic matter and TN accumulated in the spartina alterniflora flat is more than that in other ecological zones, which shows that the spartina alterniflora flat exert a non-replaceable effect on the material cycle and exchange in the whole tidal salt marshes ecosystem. 相似文献
3.
Jianhua GAO Guishan YANG Weixin OU 《Frontiers of Environmental Science & Engineering in China》2008,2(1):81-88
In order to explore the effect of different ecological zones and their above plants in the organic matter cycling of the whole
tidal salt marsh, indicators such as total organic carbon (TOC), total nitrogen (TN), C/N ratio, δ13C and δ15N of surface, core sediments, and plants of tidal salt marshes in North Jiangsu Province are analyzed. Subsequently, distribution
regularities of these measurement indicators are discussed, and the biogeochemistry processes between sediments and plants
are also analyzed. Lastly, the organic matter sources of different ecologic zones in tidal salt marsh are evaluated, and the
organic matter accumulations in different ecologic zones induced by their plants are also compared. These results indicate
that TOC, TN, C/N ratio and δ13C showed obvious zonal distribution. The organic matter sources are dominated by marine input in the silt flat, artemisia schrenkiana flat, and the transition zone between silt and spartina alterniflora flat, and are controlled by terrigenous input in spartina alterniflora flat. Spartina alterniflora plays an important role in the accumulation of organic matter in the whole tidal salt marshes ecosystem. In the study area,
the annually increased TOC, organic matter and TN in the spartina alterniflora, artemisia schrenkiana and reed flats reach 6,451, 12,043 and 536 t, respectively. The amount of TOC, organic matter and TN accumulated in the spartina alterniflora flat is more than that in other ecological zones, which shows that the spartina alterniflora flat exert a non-replaceable effect on the material cycle and exchange in the whole tidal salt marshes ecosystem.
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Translated from Environmental Science, 2005, 26(6): 51–56 [译自: 环境科学] 相似文献
4.
江苏沿海地区的相对海平面上升及其灾害性影响研究 总被引:13,自引:0,他引:13
江苏海岸是全国潮滩最集中分布区,其面积约占全国的1/4,沿海地区地势低平,相对海平面上升幅度较大,是全国少数几个受海平面上升危害最严重的地区之一。初步估算,21世纪前半期该地区不同岸段相对海平面上升速率将可能达到4.5~9.5mm/a,约为同期全球平均上升速率的2~3倍。其灾害性影响主要集中在:①造成堤外潮滩湿地资源损失,相对海平面上升50cm,因直接淹没、侵蚀加剧和淤涨减缓造成的潮滩损失面积将超过5×104hm2,湿地损失面积达2.4×104hm2;②降低海堤防御标准、危及海堤自身和受保护地区安全,相对海平面上升50cm,该地区现有海堤防御标准将由现状50~100年一遇降为20~50年一遇;遇50年一遇风暴高潮位,全区受潮水漫溢的海堤长度将比现状增加173km以上,占海堤总长的1/4;③阻碍低洼地的洪水排泄、加剧洪涝灾害损失,相对海平面上升40cm,苏北里下河和苏南太湖湖东两片洼地的自然排水能力将可能分别下降约25%和20%,若两洼地分别重现1991年型和1954年型洪水,则因海平面上升增加的受淹面积将超过4×104hm2 相似文献
5.
长江产业带投资条件比较与综合分等评价 总被引:7,自引:2,他引:5
将长江干流沿江地区建设成具有强大经济实力的国家级产业密集带是90年代国家调整宏观经济发展布局的重大战略举措。在大规模投资开发过程中如何按照各地投资环境特点,选择最佳的投资区位和适宜的投资方向是十分重要的。本文选取了能基本反映研究地区投资环境状况的基础设施条件,经济发展水平,科教发达程度,主要资源赋存和区域环境质量5类因素共14项指标,以产业带范围内的40个地市为地域单元,对产业带内部的投资环境条件 相似文献
6.
长江三角洲各类开发区发展态势与差异分析 总被引:9,自引:3,他引:6
长江三角洲地区是全国开发区类型最齐全、分布最集中和建设速度最快的地区,但内部发展很不平衡。本文总结和分析了该地区开发区发展的现状特点、存在的问题以及发展的地域差异和形成的主要原因。 相似文献
7.
杨桂山 《长江流域资源与环境》1997,6(4):295-301
在宏观分析长江下游经济带(九江以下)发展的有利条件和不利因素的基础上,选取经济基础、生产管理、基础设施劳动力素与科教实力、主要资源和环境质量状况六大影响区域经济发展的主要因素,对划分的上海、南京、杭州、宁波、扬通、芜湖和安九七个区段经济发展的条件进行了分层次的比较分析与评价,并依据评价结果与原有拉业基础,提出各区段适宜的产业重点投资方向。 相似文献
8.
苏北盐城海岸带陆源氮磷污染负荷估算初探 总被引:3,自引:1,他引:3
海岸带陆源氮磷污染输入是导致近海赤潮的主要原因,但目前尚缺乏系统的调查研究。文章采用野外实地调查和文献调研相结合的方法,从农田径流、养殖废水排放、居民生活污水和工业废水排放等几个方面,初步估算了盐城海岸带陆源氮磷污染负荷的分配情况。结果表明,盐城海岸带主要陆源污染源中,养殖水域氮磷排放总量为7641t和480t,分别占排放总量的75.1%、63.5%;其次为居民工矿的生活生产污水,其氮磷排放量为2083t和232t,占总排放量的20.5%、30.7%;农田目前看来不是盐城海岸带主要的陆源污染源,排放量仅占4.4%和5.8%。在当前海岸带陆源污染源治理中,除采取有力措施控制养殖水域养分流失外,农村和乡镇生活生产污水的排放也应引起重视。 相似文献
9.
Xu Chen Yang Guishan Wan Rongrong Ou Weixin Wang Peng 《Environmental science and pollution research international》2021,28(30):40178-40191
Environmental Science and Pollution Research - Faced with huge environmental problems of ecosystem degradation, “Ecological Redline Policy (ERP)” in China is a new key national-level... 相似文献
10.
长江江苏段岸线利用与港口布局 总被引:21,自引:7,他引:14
长江江苏段拥有全长约837km的士流岸线资源,至1997年底,实际利用率超过17%,位居沿江各省市之首,但同时也存在岸线利用缺乏统一的规划管理,造成部门与部门、地方与部门以及地方与地方之间存在矛盾、港口码头建设政出多门,布点过多、能力过大与结构雷同的重复建设现象突出的重大岸线开放工程缺乏足够的科学论证、带有一定的盲目与随意性等亟待解决的重大问题。因此,尽快制定权威的岸线功能区划和开发利用规划、建立 相似文献