河湖健康评估-河流健康和水文因素

Taizi River Basin
Shenwo Reservoir 参窝水库 Finished 1972 7.91 × 108m3
Guanyinge Reservoir 观音阁水库 Finished 1995 Tanghe Reservoir 汤河水库 Finished 1969 7.07 × 108m3 Finished 1995 21.68 × 108m3
Objectives 目标
• Assess hydrological health of Taizi River
• Try an index of hydrological stress • Develop a new method sensitive to:
– – – – Local ecological assets Local hydrology Local flow-ecology knowledge Closely linked to flow management options
Mar 10.8 13.1 12.8
Apr 19.4 11.3 13.6
May 20.0 16.1 42.8
Jun 18.6 59.3 18.8
Jul 17.1 35.1 25.8
Aug 65.3 32.7 26.6
Sep 45.3 25.6 23.5
Oct 33.2 18.0 17.7
Nov 31.0 17.1 16.4
• Ostensibly 表面上 :
– “ecologically meaningful” “生态意义”
• Warning 警告
– From a different area 从一个不同的区域 – Not linked to ecological assets of interest 没有联系到当地的生态环境
0.79
0.78
0.67
0.62
0.64
0.54
0.44
0.54
0.3
0.2 0.1
0.34 0.13 0.03
0.0
Xiaolinzi (pre-Tanghe/Shenwo V. post-Guanyinge)
Hydrological change Index value
1.0
0.9 0.8 0.7 0.6 0.5 0.4 0.66 0.58 0.65 0.48 0.34 0.10 0.03 0.86 0.90 0.937
River management policy
Social river health
Water quality Chemical
Ecological processes Biological
Main Issues 主要问题
• Hydrology RESPONDS to catchment and disturbance • Hydrology DRIVES the ecology
River Health and Hydrological Alteration 河流健康和水文因素
Dr Chris Gippel
Training Workshop Beijing 2010 November 19
Contents
• • • • • Role of hydrology as a river health indicator Introduce the Taizi River basin Apply a hydrological index Develop a new method based on flow needs Test the method in the Taizi River basin
– – – – Velocity Depth Width Shear stress
• These variables are used to determine the discharge that will satisfy the hydraulically defined ecological and geomorphological objectives
Dec 16.1 11.6 13.6
Pre-Tang/Shenwo
Post-Tang/Shenwo 10.3 Post-Guanyinge 12.6
Cease to flow
Liaoyang
350
Days of cease to flow
Cumulative annual days of cease to f low
• Is it OK to mix response and driver variables? • YES
• Hydrology is open to management action to improve health
Choices 选择
• Indicators of 指标 :
– – – – – Hydrological Hydrological Hydrological Hydrological ……. alteration stress disturbance deviation
40 35 30 25 20 15 10 5 0 Jan 3.7 Feb 3.8
15.1
Mar 4.0
16.1
Apr 8.7
19.1
May 20.8
23.0
Jun 17.3
27.5
Jul 23.5
28.4
Aug 38.6
16.6
Sep 26.0
12.1
Oct 15.1
18.7
Nov 11.1
16.9
Hydrological change Index value
1.0
0.9 0.8 0.7 0.6 0.5 0.4 0.74 0.991 0.92
1.0
0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 0.06 0.09 0.32 0.00 0.68 0.77 0.84 0.912
Jan Feb Mar Apr May Jun
Jul
Aug Sep Oct Nov Dec
Relative IQ range
Jan Feb Mar Apr May Jun
Jul
Aug Sep Oct Nov Dec
Flow Stress Indicator
• • • • • • • • Mean annual flow Seasonal difference Seasonal timing Low flow magnitude High flow magnitude Days of river drying up Flow duration Flow variability
0.75 0.67
0.53
0.3
0.2 0.1 0.23 0.13 0.00
0.0
Xiaolinzi (pre-Tanghe/Shenwo V. post-Tanghe/Shenwo)
Hydrological change Index value
Liaoyang (pre-Tanghe/Shenwo V. post-Guanyinge)
Liaoyang (pre-Tanghe/Shenwo V. post-Tanghe/Shenwo)
Hydrological change Index value
1.0
1.0
0.9 0.8 0.7 0.6 0.5 0.4 0.60 0.60 0.77 0.87 0.73 0.55 0.59 0.980
– – – – Velocity Depth Width Shear stress hydraulics
Flow components
King et al (2008) Building Block Method
Baseflows
Benxi
45
Median baseflow daily discharge (m3/s)
Yingkou
Flow data from 1950s
Daily discharge (m3 /s)
Daily discharge (m3 /s)
2,000
1,500
Flow exceeded 5 percent of the time
Benxi
2,500 2,000 1,500 1,000 500 0
Catchment management policy
Physical Geology Climate Land use Hydraulic habitat
Economy Education Trade, etc
Hydrology
Geomorphology
Ecological river health
Benxi (pre-Guanyinge V. post-Guanyinge)
Hydrological change Index value
0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 0.10 0.18 0.35 0.59 0.47 0.683 0.99 0.85
Jan Feb Mar Apr May Jun
Jul
Aug Sep Oct Nov Dec
Relative interquartile range [IQ range/median]
Relative interquartile range [IQ range/median]
Relative IQ range
Dec 5.6
13.9
Pre-Guanyinge Dam
Post-Guanyinge Dam 14.2
Baseflows
70
Tangmazai
Median baseflow daily discharge (m3/s)
60 50 40 30 20 10 0
Jan 9.3
Feb 8.6 10.0 13.3
Annual peak cease to f low spell duration
300
250 200
150 100 50
0
Tangehe Shenwo
Guanyinge
Flow events
Frequency
Duration
Hydraulic information
• • • • No surveys Need to find whatever is available Gauging stations have useful information Can derive as a function of discharge:
Benxi
18/06/2001 24/05/1978
120
Elevation (m ASL)
115 110 105
100
0 50 100 150 200 250 300 350
Can measure differences in periods Does not work on a single year
0.46
0.3
0.2 0.1
0.0
Rapid eco-hydraulic environmental flows assessment
• We need to know about the eco-hydraulics • What specific flows will satisfy the needs of the identified ecological assets? • Ecology responds to
Median and Interquartile range [exceeded 75 - 25 percent of time]
Jan Feb Mar Apr May Jun 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0
Jul
Aug Sep Oct Nov Dec 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0.0
Jul Aug Sep Oct Nov Dec
Median and Interquartile range [exceeded 75 - 25 percent of time]
Daily discharge (m3 /s)
Daily discharge (m3 /s)
1,000 800 600 400 200 0
Flow exceeded 5 percent of the time
Tangmazai
1,源自文库00
500
0 Jan Feb Mar Apr May Jun 350 300 250 200 150 100 50 0 Jul Aug Sep Oct Nov Dec
Jan Feb Mar Apr May Jun