• 论文 •

### 环境变化对黄河下游来水来沙的影响

1. 中国科学院国家计划委员会地理研究所, 北京 100101
• 收稿日期:1994-07-01 修回日期:1994-09-01 出版日期:1995-01-15 发布日期:1995-01-15
• 基金资助:
黄河水沙变化研究基金

### IMPACT OF ENVIRONMENTAL CHANGE ON COMING WATER AND SEDIMENTS AT THE LOWER REACHES OF HUANG HE (YELLOW RIVER)

You Lianyuan, Yang Jiwu

1. Institute of Geography, Chinese Academy of Sciences and the Stare Planning Commission of the People Republic of China, Brijing. 100101
• Received:1994-07-01 Revised:1994-09-01 Online:1995-01-15 Published:1995-01-15

Abstract: This paper deals with the problem on coming water and sediments at the lower reaches of Huang He (Yellow River) by the year of 2050 resulted from environmental change. 3 main aspects of environmental changes are considered in this paper. They are (1)global change (global warming); (2) long-term change of temperature and precipitation and (3) human activities. To study this problem, a set of empirical formulas between precipitation and runoff, and between runoff and sediment discharge are established for calculation after these factors are changed during 70 years. Almost all of coming water and sediments at the lower reaches of Huang He come from the upper and middle reaches of Huang He which have a large area (730 000 km￣2) and obvious differences in geographical environment, and have different relationships among preciprtation, runoff and sediment discharge. The whole Upper and Middle Huang He region may be distinguished into 9 different semi-regions, for each of them a set of empirical formulas are established. There are 54 empirical formulas in total. The sum of values calculated from 9 semi-regions represents the total coming water and sediments entered into the lower Huang He. These formulas have very good relationships with a correlative efficient of 0. 70-0. 8 or even better.1. Impact of global warming on coming water and sediment Based on the report from IPCC, if green gases concentration in the atmosphere increases with present rate continuously. its content would be twice of the present one by the year of 2050. Consequences would be as follows:(1)Annual temperature rises 1.5-4. 5℃ over that of the present one.The temperature increment of the high latitude zone is more than that of the low latitude one and the increment in winter is higher that in summer. (2) Annual precipitation goes up about 7%-11%compared with the present, but this will happened mainly in the high latitude and the tropical zone.Recent study on the information from China, which is obtained by the model NCAR of US.shows that the temperature of the Huang He basin would rise 4. 6℃ (annual) . and the increment in winter is higher than that of summer. These values correspond with the result of IPCC and are the basis for calculating and predicting conditions of coming water and sediments at the lower reaches of Huang He.Using the mentioned empirical formulas and values, it is easy to get the result of the coming water and sediment at the lower reaches of Huang He. Comparing with the present, they would increase by about 2. 96% and 8. 0% (annual) . and 4. 28% and 3. 14% (flood season) respectively.2. Impact of long-term change on coming water and sediment It is well known that there is periodical change in temperature, precipitation, runoff, drought and waterlogging etc. Doubtless. long-term change is important for predicting information by years of 2050. In the Huang He Basin there is an 130- 150 year changing cycle of drought and waterlogging. At present, it is at the early stage of the next moist period and would go to the flourishing stage by the years of 2050. According to the calculation using the conversion formula. the precipitation of the flood season would increase by 15. 2mm at that time. Similarly, using the mentioned formulas about precipitation-runoff-sediment discharge. it may be calculated that the runoff and sediment discharge of the flood season would increase by 10. 95 ×10￣8m￣3 and 0. 195×X 10￣8t respectively.Summing these values and the values in the Tab. 1, it is estimated that the coming water and sediment discharge of the lower reaches of Huang He in the flood season by the years of 2050 would be about 287. 6 ×10￣8m￣3 and 11. 95 ×10￣8t respectively. The annual runoff and sediment discharge would be 407 × 10￣8m￣3 and 13. 29 × 10￣8t respectively.3. Effects of human activities Effects of human activities include 2 aspects positive one, such as methods of hydraulic and water conservation, negative one. such as unreasonable landuse,destruction of forest. It is very difficult to make a real estimation of runoff and

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