Document Type : Research Paper

Authors

1 M.Sc. in Range Management, Research Assistant, Research Center of Agriculture and Natural Resources, Yazd Province

2 Ph.D. Student in Range Management, Assistant professor, Islamic Azad University of Yazd

3 Ph.D. Student in Watershed Management, University of Hormozgan

Abstract

A better understanding of rangeland vegetation cover and its variation in different years based
on wetness and droughtiness fluctuations is a great importance. Economical priority setting of
rangelands is based on variations in rainfall and drought patterns, because it yields to better
characterization of vegetative cover. Yet a comprehensive and continuous monitoring of
vegetative cover of rangelands has not been established. To study the influence of droughtiness
and wetness on vegetation cover and production forage, 11 sampling areas and 3 reference
areas were selected in Herat. Three 100-m transects were located 25-m apart within each
sampling area. Production and cover were estimated within 10 located 2- plots along each
transect. Data were analyzed using Duncan›s test Design a completely random with a factorial
GLM procedure at 99% and 95% confidence levels. Results showed that the vegetation cover
and production in wetness were significantly different from those in droughtiness (P<0.01).
The vegetation production and cover increased by 36.3% and 34% respectively in the wetness
compared to the droughtiness. The influence on production and cover was positive and efficient
in the wetness with the average rainfall higher than the 30-yr average. Finally, the results of
flood spreading increased vegetation cover and production forage in dams.

Keywords