Document Type : Research Paper
Authors
- Shafagh Rastgar 1
- Hossein Barani 2
- Ali Darijani 3
- Vahedberdi Sheikh 2
- Jamshid Ghorbani 4
- Mohammad Ghorbani 5
1 Assistant Professor, Faculty of Natural Resources, Sari University of Natural Resources and Agricultural Sciences, Sari, Iran
2 Associate Professor, Faculty of Natural Resources, Gorgan University of Natural Resources and Agricultural Sciences, Gorgan, Iran
3 Assistant Professor., Faculty of Agricultural Economy, Gorgan University of Natural Resources and Agricultural Sciences, Gorgan, Iran
4 Associate Professor, Faculty of Natural Resources, Sari University of Natural Resources and Agricultural Sciences, Sari, Iran
5 Professor, Faculty of Agricultural Economy, Ferdowsi University of Mashad, Iran
Abstract
Vegetation cover as the main factor affecting the water erosion plays an important role in preventing
soil loss. To this end, for better understanding the impact of vegetation cover on soil erosion and
sediment yield over the major existing geological formations in the summer rangelands of Balade in
the Mazandaran province, rainfall simulation studies have been carried out using a portable rainfall
simulator. Among many geological formations across the study area, the three major lithological units
of mica sandstone, clay and shale sandstone with coal seams of “SHEMSHAK”, structures of tuff
shale and dark gray to green shale with volcanic rocks of “KARAJ” and limestone of “LAR” have
been selected as lowly, moderately and highly resisting formations to degradation. For each
combination of geological formation and vegetation cover (low, moderate, and high density) three
sampling plots of 1x1m have been selected and rainfall simulation has been conducted over them. For
each plot, the surface characteristics including the vegetation cover, runoff and sediment yield and soil
texture were measured. The measured data were statistically analyzed. Results showed that
“SHEMSHAK”, “KARAJ” and “LAR” formations were respectively ranked from highest to lowest
with respect to the volume and weight of sediment yield. Also, there was a strong inverse relationship
between vegetation cover percentage and volume of runoff and sediment for all investigated
geological formations specially in poor vegetation situation that indicate interaction effects between
vegetation cover and type of geological formations.
Keywords
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