|
Back Volume
Current Volume
Next
Volume
|
Prioritization of Watershed using Sediment Yield Index Method: A Case study of Semi-Arid Ecosystem
of South India
K.C. Arun Kumar1, *,
P. Sandeep1 and P. Masilamani2
1ICAR-National Bureau of
Soil Survey & Land Use Planning,
Amravati Road, Nagpur-440 033, India
2Department of Geography, Bharathidasan
University, Tiruchirappalli,
TamilNadu-620 024, India
*Email Id: arunkumar.kc@yahoo.com
Watershed;
Sediment Yield Inde;
Prioritization;
Sarabhanga
|
|
Abstract
Soil erosion is a severe problem in arid and
semi-arid environments, especially on grazing land, where extreme rainfall
intensities of short duration, soil vulnerability to erosion, and human
land mismanagement have increased soil degradation by erosion leading to
sedimentation downstream. For the better agricultural sustainable
development, estimation of soil sedimentation is critical for watershed
planning, prioritization and development. A sediment yield index (SYI)
model describing the relative yield of sediments from various
sub-watersheds works out the preferences for soil and water conservation
interventions in a watershed. The study recognizes the extent of soil loss
and recommends a method for prioritization of sub-watershed in the Sarabhanga watershed of Tamil Nadu state by integrating
the topography, soil, rainfall erosivity and land use/land cover parameters
under 17 sub-watersheds with a Geo-informatics approach. Of the 17
sub-watersheds, five sub-watersheds (SB-6, SB-3, SB-14, SB-12 and SB-5) came
into the extremely high priority category, with a higher SYI value
(>170) and covering 584.3 sq. km, about 49.7% of the Sarabhanga
watershed due to high rainfall and high slope value imply that these
sub-watersheds have a high potential for erosion and sedimentation. Six
sub-watersheds (SB-1, SB-11, SB-2, SB-13, SB-4 and SB-15) were classified
under a low priority class covering an area of 233.4 sq.km (19.9%) and
these sub-watersheds have low amounts of precipitation and less than 70 SYI
values. The study comments on conservation techniques that can be adopted
in the Sarabhanga watershed to the increase agro pastoral efficiency.
|
Download
PDF
|
