Term
| What are the differnt types of terraces? |
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Definition
- Bench terrace
- graded terrace- graded channel to collect runoff and slowly leads it to a vegetated area
- level terrace- level channel that holds water behind the ridge until it is absorbed by the soil
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Term
| how are the baks of the bench terrace generally supported? |
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Definition
| by vegetation or neatly fitted stonework |
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Term
advantages and disadvantages of graded terraces?
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Definition
Advantages
even if runoff is not reduced, the slope legnth is shortened, thus slower velocity.
plants/seeds are less likely to be damaged by erosion
Disadvantages
acutally increase land slope because the vertical fall from one terrace to the next is increased by the hight of the ridge crest above the channel bottom.
Reduces productive capacity of channel areas on shallow soils
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Term
advantages and disadvantages of steep-backslope terraces?
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Definition
Advantages
easy to farm
reduce the gradient of cropped area between terraces
Disadvantages
untillable backslope which reduces cultivated area
reduce field equipment usage to up and down
rodent burrow in ridges |
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Term
| What is the horizontal interval? |
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Definition
| the horizontal interval, not the distance between terraces measured across the surface of the land |
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Term
| How should construction of terraces happen? |
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Definition
clear field of trash
smooth preliminary land
fill dead furrows
level small ridges
remove topsoil, stockpile it and bring it back after construction
build with large scale equipment, tops of ridges must be leveled |
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