Soil Lec (Reading Assignments) Flashcards
principles of erosion
- limit detachment
- limit transport
- reduce runoff, increase infiltration, roughen surface and reduce slope
types of check dams
- masonry check dam
- rock / stone check dam
- earth check dam
- pole / log check dam
- brushwood check dam
Structural / Mechanical Methods
- terracing
- countour canals
- contour rock walls
- gabions
- riprap
- stone wall
- farm ponds / water impounding dams
- check dams / drop weirs
- drainage systems / canals
- diversion ditches
They are more permanent structures that are built in areas with large rocks
Contour Rock Walls
True or False
terracing is considered a traditional practice in the cordillera areas
true
Construction of earthen embankment adjusted to soil and slope tocontrol runoff. It is primarily designed to control runoff in areas of high rainfall andconservation of water in low rainfall areas
Terracing
A shallow ditch that runs horizontally across the slope following the contour of the land
Contour Canals
Simple structure that can stop gully erosion by slowing down the water flowinthe drainage system
Check Dams/ Drop Weirs
Rocks or stones are loosely piled up but with sufficient overlap to produce a single effect forming a check dam
Rock/Stone Check Dam
Involves the use of stones as walling material
Stone Wall
Use loose earth (clay materials) for check dam construction
Earth Check Dam
Use of poles or logs as check dam materials
Pole/Log Check Dam
Rocks fitted/piled on the top of each other to form a retaining wall
Riprap
Use of large rectangular wire crates filled with stones acting as retainingwall
Gabions
Depression on the farm, especially in heavily gullied areas
Farm Ponds/ Water Impounding Dams
Used in gullies or stream channels with high rates of runoff or where vegetation cannot be established
Masonry Check Dam
refers to the systematic planting of different crops in succession on the same piece of land
Crop rotation
Involves the growth of cover crops such as grasses and / or legumes to protect the soil/ground surface from the impacts of raindrops whichcausesdetachment and dispersion
Cover cropping
refers to growing row crops and soil conserving crops in alternate strips aligned on the contour
Strip cropping
Biological/Agronomic Approach
- cover cropping
- multiple cropping
- strip cropping
- crop rotation
- relay cropping
- mulching
- contour hedgerows
- contour buffer strip planting
- alley cropping
- fascines
- wattling
- brush cover
- brench brush layers
Use to divert runoff from gully head to prevent further enlargement and facilitate gully control works
Diversion Ditches
These are small channels/canals that run vertically on the slope
Drainage Systems/Canals
Use of brushwood (sprouting or non sprouting) that are packed firmly between two rows of post-drive across the gully bed
Brushwood Check Dam
A line usually planted to perennials close together to form a living wall; this wall blocks the rainwater pathway while the soil is caught behind theplants
Contour Hedgerows
