摘要
在月湖进行了沉积物采样和潮汐水文观测 ,分析计算了表层沉积物类型、泥沙输运率、现代沉积速率 ,讨论了月湖的沉积物平衡。结果显示 ,月湖的沉积速率较快。按目前的数据和资料估算 ,月湖每年的沉积通量约为(1.8～ 2 .3)× 10 4t,而正常情况下的沉积物供应量每年只有 (0 .5～ 1.2 )× 10 4t。研究表明 ,人类活动还改变了月湖的物理与生态过程。由于土地利用的方式及其强度发生了变化 ,月湖汇水盆地的侵蚀量大为增加 ,侵蚀模数可能远大于 4 0 0t/ (km2 ·a) ,从而使流域侵蚀量大大超出了正常范围 ,加剧了月湖的淤积。
In the latest two decades, deterioration changes of physical and ecological environment happened in Yuehu, a small inlet-lagoon system located in the eastern part of Shandong Peninsula, China, mainly due to human activities.In order to investigate the sediment dynamic behaviour of the Yuehu, measurements and sampling were undertaken to obtain data sets of tidal water levels, current velocities, suspended sediment concentrations, grain size parameters, and organic carbon contents. With these data, analysis of surficial sediment distribution, grain size trends, sediment transport rates, deposition rates, and sediment budget were carried out.The results show that the deposition rates are relatively high within the tidal basin. Based on ^(210)Pb dating and short cores analysis, sediment flux into Yuehu Lagoon is estimated to be 1.8×10~4-2.3×10~4 t/a, whereas sediment input from the open sea, the aerosol and biological production, and the material from land is only 0.5×10~4-1.2×10~4 t/a; In another word, the total sediment flux cannot be balanced by the input. Thus, the denudation rate over the catchment basin of Yuehu Lagoon, representing a major component for the balance, was underestimated. Inferred from the aero-photos derived land use patterns, the material from land has been intensified by agricultural activities over the past several decades. Therefore, the denudation rate, must be much higher than 400 t/(km^2·a). Besides land use patterns, many physical and ecological processes in Yuehu Lagoon have been altered by local inhabitant. Evolution of Yuehu Lagoon show that human being should put their development activities under the control of natural rules, otherwise un-reversible changes would happen.
出处
《地理科学》
CSCD
北大核心
2004年第1期83-88,共6页
Scientia Geographica Sinica
基金
国家自然科学基金资助项目 (4 0 2 0 60 0 6)
国家杰出青年基金项目 (4 972 5 612 )
关键词
潮汐汊道
沉积物平衡
沉积速率
月湖
人类活动
tidal inlet system
sediment budget
deposition rate
Yuehu
human activities
