亚洲一区亚洲二区亚洲三区,国产成人高清在线,久久久精品成人免费看,999久久久免费精品国产牛牛,青草视频在线观看完整版,狠狠夜色午夜久久综合热91,日韩精品视频在线免费观看

Temporal and spatial variations of t

時間:2023-04-29 05:30:06 天文地理論文 我要投稿
  • 相關(guān)推薦

Temporal and spatial variations of the Huanghe River mouth bars

On the basis of the bathymetric records of 371 survey sections in the present Huanghe mouth area from 1996 to 2001, the temporal and spatial variations of the Huanghe mouth bars were studied by using GIS technology. The variation of the mouth bars is closely related to the water and sediment discharges from the Huanghe River to the sea that has been decreasing drastically in recent years, and to coastal hydrodynamic regimes. The characteristics of the mouth bars are unique in contrast with those of other estuaries in the world (1) The mouth bars of the Huanghe River consist of many small sandbars. Usually the sandbars are of ellipse-shape with the long axis of about 1~6 km, and short axis of about 1~4 kin. The long axis is parallel to the principal direction of tidal current, and the short axis is variable, depending on the local dynamics. The crest of the sandbars is only about 0.4 m below the water surface at low tide. They are distributed within an area of 20 km2, not far from the river mouth area. The present mouth bars are in small-medium size, quite different from the large one formed during the 1970s and 1980s, when the river sediment discharge was several times larger than that after 1996. (2) The scale of a river mouth bar is related to the river discharge of that year. In 1997 sediment discharge from the Huanghe River was 42 Mt, and the mouth bar consisted of several small scattered sandbars. In 1998 the size of mouth bars was much larger thar that in 1997, as the sediment discharge from the Huanghe River increased to 363 Mt. Variation of the mouth bars largely depends on the sediment discharge with a correlation coefficient of 0.78. The calculation of the volume of the mouth bar area shows that about 30%~40% of the river's into-sea sediment is deposited in the mouth bar area. (3) Compared with other large estuaries in the world, the Huanghe mouth bars have three unique features in responding to its high sediment concentration: small size, steep slope gradient and shallow crest depth.

作 者: Yang Zuosheng ZHANG Yong Liu Zhan WEI Helong HE Shufeng   作者單位: Yang Zuosheng,ZHANG Yong(Institute of Estuarine and Coastal Studies, Ocean University of China, Qingdao,266003, China)

Liu Zhan(University of Petroleum (East China), Dongying, 257061, China)

WEI Helong(Institute of Estuarine and Coastal Studies, Ocean University of China, Qingdao,266003, China;Qingdao Institute of Marine Geology, China Geological Survey, Qingdao,266071, China)

HE Shufeng(Qingdao Institute of Marine Geology, China Geological Survey, Qingdao,266071, China) 

刊 名: 海洋學(xué)報(英文版)  SCI 英文刊名: ACTA OCEANOLOGICA SINICA  年,卷(期): 2005 24(2)  分類號:   關(guān)鍵詞: Huanghe mouth bars   temporal and spatial variations   mechanism of formation  

【Temporal and spatial variations of t】相關(guān)文章:

Temporal and spatial variations of atmospheric methane concentration and δ13C-CH4 near the surface on the Millor Peninsu04-27

Spatial and temporal variability of agricultural pollutants in an agricultural headwater stream within a multipond syste04-26

Variations in seed germination of Hippophae salicifolia with different presoaking treatments04-26

Generation and Application of Spatial Atmospheric Turbulence Field in Flight Simulation04-26

An analysis on spatial variation of urban human thermal comfort in Hangzhou,China04-26

STUDY ON SPATIAL LANDSCAPE PATTERN OF YANTAI CITY BASED ON RS AND GIS04-27

FEATURES AND COMPARISONS OF THE QUASI-BIENNIAL VARIATIONS IN THE ASIA-PACIFIC MONSOON SUBSYSTEMS04-27

白t恤搭配09-14

d t n l教案03-08

什么是黃金T+D04-28