LEC 10 Flashcards
A ____ is an earth-embankment, constructed across the slope, to control runoff and
minimize soil erosion.
Terrace
acts as an intercept to land slope, and divides the sloping
land surface into strips.
TERRACE
soil loss is ___to the square root of the length of slope
proportional
Terraces are classified into to two major types:
broad-base terraces and bench terraces
______ are adapted where the main purpose is either to remove or retain water on sloping land suitable for cultivation
Broad-base terraces
the purpose of ______ is mainly to
reduce the land slope.
bench terraces
used for hilly areas with a grade reversely towards the hill.
Hill-type bench terraces
level benches adopted under irrigated conditions
Irrigated bench terraces
Orchard bench terraces: narrow width terraces for individual trees. These are also referred
to as ____
intermittent terraces and step terraces.
The conversion of land into bench terraces over a period of time is referred to as ____.
gradual
bench terracing
Bench terraces are classified depending upon the slope of benches. The
different types are:
(i) bench terraces sloping outward;
(ii) bench terraces sloping inward; and
(iii) bench terraces with level top.
For the designing of the bench terraces for a particular tract _____, _____, ______, and _______ should be known.
the average rainfall; the
soil type; soil depth; the average slope of the area
___ is generally expressed as the vertical interval between two terraces.
Terrace spacing
The ____ (D) is dependent upon the depth of the cut and since the cut and fill are to be balanced, it is equal to double the depth of cut.
vertical interval
The __ should be always open and properly graded; water must not be allowed to
accumulate in any part of the terrace.
toe drains
