植被对水土流失和水源涵养的影响_水务讲座PPT

➢ Vertical vegetation structures;
➢ Plant diversity ;
➢ Vegetation spatial distribution
(Crockford and Richardson, 2000; Li et al., 2014; Quinton et al., 1997; Janssens et al., 1998; Martin et al., 2010; Puigdefabregas, 2005; Bochet et al., 1998; Feng et al., 2012; Lu et al., 2012; Liu et al., 2018; )
Grass: Carex
Duration of rainfall: 60min
Shrub: Twigs of the CHASTE Tree Slope：15°
Measuring experimental indexes
Control condition
Methods
Vegetation Coverage: 0, 25%, 50%, 75%,100%; Litter Coverage: 0, 50, 100, 150，200, 250g/m2
0 0
0
25%
50%
75%
100%
10
20
30
40Biblioteka 5060TimeSurface Runoff (ml/min)
1100 1000 900 800 700 600 500 400 300 200 100
0 0
0g 50g 100g 150g 200g 250g
Time/min
5 10 15 20 25 30 35 40 45 50 55 60 65
Effects of vegetation and litter coverage on soil erosion process
Slope Runoff and Sediment Process
Surface runoff rate (mL/min)
1200 1000
800 600 400 200
0g
50g
100g
150g
200g
250g
10
20
0g
30
40
50
50g
100g
60
70
80
90
Time/min
150g
200g
250g
Infiltration rate(mm/min)
Infiltration rate(mm/min)
0.20
0.20
0.00 0
10
20
30
40
50
60
Duration of rainfall(min)
0
25%
50%
75%
100%
10
20
30
40
50
60
70
80
90
Time(min)
0
25%
50%
75%
100%
Soil moisture increment
10.00 9.00 8.00 7.00 6.00 5.00 4.00 3.00 2.00 1.00 0.00 0
1.00
0.80
0.60
0.40
✓ Helps the ground to absorb water;
✓ Slows the runoff velocity and traps sediment.
Questions discussed in this research :
1. How does the vegetation coverage and litter coverage influence soil erosion process? What is the dynamic process of soil water infiltration during rainfall?
第十四届中国国际水务高峰论坛暨北京生态修复学会年会
植被对水土流失和水源涵养的影响
北京林业大学水土保持学院 2019年11月5日
国家科技重大专项（水体污染控制与治理）--冬奥会核心区生态修复与水源涵养 功能提升技术与示范
Multidimensional analysis of the effects of vegetation on runoff and soil loss
EFFECTS OF VEGETATION IN MINIMIZING EROSION
✓ Absorbs the energy of falling rain;
✓ Removes water from soil and transpires it into the air;
✓ Roots hold surface soil and stabilize bank materials;
2. The regulation mechanism of vegetation coverage on soil erosion?
Methods
Runoff bucket
Precondition of experiment Rainfall simulation experiment
Vegetation coverage/Litter coverage Rainfall intensity: 60mm/h
rate under different vegetation coverage conditions
Fig. 2 Dynamic changes of surface runoff rate and sediment rate under different Litter coverage conditions
0
25%
50%
75%
100%
Sediment rate (g/min)
2108..0000 16.00
14.00
12.00 10.00
8.00
6.00 4.00 2.00 0.00
0
Time
10
20
30
40
50
60
Fig. 1 Dynamic changes of surface runoff rate and sediment
Effects of vegetation and litter coverage on soil erosion process
Slope Soil Infiltration Process
Soil moisture increment
14 12 10
8 6 4 2 0
0
1.20 1.00 0.80 0.60 0.40