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作 者:许炯心[1]
机构地区:[1]中国科学院地理科学与资源研究所,北京100101
出 处:《地理科学进展》2001年第1期1-9,共9页Progress in Geography
基 金:中国科学院知识创新工程重要方向项目! (KZCX2 - 2 0 70 5);国家重点基础研究规划项目!(G1 9990 4 360 4 )
摘 要:以近 50年来的观测资料和公元 1 1 94年以来苏北废黄河和现代黄河的历史文献资料为基础 ,在宏观时间尺度上 (1 0 2 ~ 1 0 3年 )研究了人类活动对黄河口延伸速率的影响。结果表明 ,废黄河口的延伸可以分为两个阶段 ,1 1 94~ 1 578年为第一阶段 ,河口延伸速率较慢 ;1 579~ 1 855年为第二阶段 ,河口延伸速率大大加快。 1 855年以来现代黄河河口延伸速率的变化曲线可以分为 3个阶段 ,分别用 3条斜率不同的直线来拟合。 3条直线之间的两个转折点可以代表人类活动的方式和强度发生改变的临界点。Based on the instrument measured data in the past 50 years and the data extracted from historical documents, a study has been made of the human activities on the river mouth extension, at a time scale of 10 2~10 3 years. During the period studied, the Yellow River empties into the Yellow Sea and Bohai Sea, successively, and the deltas it has shaped are known as Abandoned and Modern Yellow River Deltas. The extension of the Abandoned Yellow River can be divided into 2 stages. The first is from 1194 to 1578, during which the extension rate of river mouth was rather slow. The second is from 1579 to 1855, during which the extension rate was greatly accelerated. The curve showing the temporal variation of the extension rate of the modern Yellow River Mouth can be fitted by 3 straight lines with different slopes. Accordingly, the change from 1855 to present can be divided into 3 stages, and the turning points between the 3 straight lines may be regarded as the threshold points that indicates the marked changes in the manner and degree of human activities. On this basis, a 3 stage model has been put forward to describe the process of river mouth extension as a response to the changing human activities.
分 类 号:X144[环境科学与工程—环境科学]
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