Your SlideShare is downloading. ×
0
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Chapter 6 Fetter Soil moisture and groundwater recharge
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Chapter 6 Fetter Soil moisture and groundwater recharge

647

Published on

Chapter 6 Fetter Soil moisture and groundwater recharge

Chapter 6 Fetter Soil moisture and groundwater recharge

Published in: Education, Technology
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
647
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
43
Comments
0
Likes
1
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. Al-Azhar University-Gaza Master Program of Water and Environmental Science Soil Moisture and Groundwater Recharge prepared by Safaa A. EL Derawi
  • 2.  Introduction The uppermost layer of the earth may contain a three phase system of material:  solid  liquid  gaseous
  • 3. The earth layer that contain the three phase system is called the: vadose zone also know as zone of aeration, and unsaturated zone .
  • 4. Porosity and water content of soil
  • 5.  Porosity
  • 6.  The void ratio of the soil is the ratio of volume of the voids to the volume of the solids.
  • 7. V= Vv + Vs , n= Vv/V n= Vv / Vv +Vs divide by Vs V= Vv + Vs , e= Vv/Vs e= Vv / V - Vv divide by V
  • 8.  The gravimetric water content  The volumetric water content  The saturation ratio
  • 9. Bulk Soil = Particle volume + pore volume  The dry bulk density :  The particle density:
  • 10.  Porosity can be calculated in practice:
  • 11. Soil Water Measurement Measures mass water content  Take field samples  weigh(Wm)  oven dry at 105 C  weigh ( Ws) until a constant mass is obtained Ww=Wm-Ws Gravimetric water content = Wm-Ws / Ws and Vw = (Wm - Ws / w )/V Volumatric water content =Vw/V
  • 12. Electrical Resistance Blocks & Meters
  • 13.  Capillarity and the capillary fringe Capillary forces : The forces acting on soil moisture in the unsaturated zone, attributable to molecular attraction between soil particles and water.
  • 14. The capillary rise in cm is : Capillary Rise
  • 15. Capillary fringe :
  • 16. The zone of aeration is best defined as the zone where the soil moisture is under tension
  • 17.  Pore-water tension in the vadoes zone  Fluid pressures in the vadose zone are negative  The negative pressure head is measured in the field with a tensiometer
  • 18. Tensiometer for Measuring Soil Water Potential Water Reservoir Variable Tube Length (12 in- 48 in) Based on Root Zone Depth Porous Ceramic Tip Vacuum Gauge (0-100 centibar)
  • 19.  soil water is the water in the vadoes zone, that is available to growing plants.
  • 20. Soil moisture depend on: 1. Change in the amount of precipitation. 2. Change in the amount of evapotranspiration
  • 21. Types of soil water
  • 22. Field Capacity - Wilting Point
  • 23.  Theory of Unsaturated Flow The infiltration of water into the unsaturated can be considered in terms of:  Gravity potential, Z  Moisture potential, ψ
  • 24. Darcy’s law is valid for flow in the unsaturated zone. Is not constant , content is a function of the volumetric water
  • 25. Idealized curves showing relationships of volumetric water content, hydraulic conductivity, and soil-moisture head
  • 26.  Water-Table Recharge When the front of infiltrating water reaches the capillary fringe, it displaces air in the pore spaces and cause the water table to rise.
  • 27. Rate of Recharge The rate of water-table recharge depends on: 1. Thickness of the unsaturated zone (The thinner zone, the faster rise of water table) 2. The vertical unsaturated hydraulic conductivity 3. The permeability . May generate a localized ground-water mound

×