Optimization of regional characteristic indicators for ecological flow in the lower reaches of Hanjiang River
- Article
- Figures
- Metrics
- Preview PDF
- Reference
- Related
- Cited by
- Materials
Abstract:
People's development and utilization of the river are increasing because of power generation, navigation, and irrigation, at the same time, the hydrological regime of the river and the ecological environment has also caused a certain impact. When evaluating the changing characteristics of river hydrological alterations, utilizing the ecohydrological index system is often necessary to quantify the degree of river hydrological changes. Due to the large differences in climatic conditions, geomorphological features, and hydrological-ecological response relationships in different study areas, problems of correlation between indicators and data redundancy in the traditional hydrological alteration index method (IHA) may cause the overall evaluation bias.The evaluation of the hydrological regime of the river in the lower reaches of the Hanjiang River was carried out considering the influence of the average daily flow, the shape of the river cross-section, and water intake and diversion projects of the main and tributary streams in the Hanjiang River basin. For this purpose, three hydrological stations on the main river basin of the Hanjiang River and three hydrological stations in its tributary basins were selected, and the IHA indexes of the six hydrological stations in the basin were optimized by the principal component analysis method, and then further screened based on the results of the correlation test method.The results showed that: Thirteen representative indicators were February flow, April flow, July flow, October flow, December flow, base flow index, lowest flow occurrence date, highest flow occurrence date, number of low-flow pulses, high flow duration, average daily flow increase rate, average daily flow reduction rate and reversal numbers. The correlation test analysis showed that the correlation of the thirteen representative indicators of the six hydrological stations was greatly reduced, and the correlation coefficients between 70% of representative indicators did not exceed 0.3. The difference between IHA indicators and the representative indicators on the overall hydrological alteration degree of the lower Hanjiang River basin was less than 7.5 percentage points verified by the RVA method.Considering the different hydrological situations of the rivers in the mainstream and tributary basins of the lower reaches of Hanjiang River basin, different hydrological stations are optimized for representative indicators, which can evaluate the hydrological situation of the entire lower reaches of Hanjiang River basin. The representative indicators can provide a more comprehensive and reasonable evaluation of the hydrological regime of the entire lower reaches of Hanjiang River basin, which is convenient for evaluating the degree of impacts of human activities on the river promptly.
Keywords:
Project Supported:
Clc Number:
Mobile website
® 2024 All Rights Reserved
冀公网安备13010502002656号
冀公网安备13010502002656号