Ali Jafari; Aliakbar Nazari Samani; Fatemeh Tavakolirad
Abstract
Doing the research for monitoring, evaluating and comparing the results with the parameters of projects is essential in the most natural resources and watershed management projects. Also in flood spreading projects the measurement, processing and evaluating the obtained information seems necessary. ...
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Doing the research for monitoring, evaluating and comparing the results with the parameters of projects is essential in the most natural resources and watershed management projects. Also in flood spreading projects the measurement, processing and evaluating the obtained information seems necessary. Entrance the large amount of flood with suspended material and sedimentation, changes the soil properties gradually. In this study influence of flood spreading on soil mineralogy changes was evaluated after 10 years. In order to investigate the changes in flood spreading ditches, three rows between the spreading channels which had received the flood were chosen as the sampling sites. To investigate and identify the clay minerals of flood spreading area and compared with the control area near to flood spreading area, thirteen samples of 0-15cm soil horizon from three flood spreading rows and settling ditches were selected. The results obtained from X-ray diffraction curves showed the presence of palygorskite, Illite, chlorite, smectite and kaolinite in control area, three settling ditches and flood spreading rows. There was no difference between the types of clay minerals in control area with settling ditches and flood spreading rows but the amount of some clay minerals was different in these situations. It seems that the dry climate of region was the serious factor in no change of clay minerals. Flood spreading had little effect on types of clay minerals and just was able to change the amount of clay minerals in flood spreading rows.
Alibeman Mirjalili; Mohammad Musaei Sanjeraei; Shahabodin Zarezadeh Mehrizi
Abstract
A better understanding of rangeland vegetation cover and its variation in different years basedon wetness and droughtiness fluctuations is a great importance. Economical priority setting ofrangelands is based on variations in rainfall and drought patterns, because it yields to bettercharacterization ...
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A better understanding of rangeland vegetation cover and its variation in different years basedon wetness and droughtiness fluctuations is a great importance. Economical priority setting ofrangelands is based on variations in rainfall and drought patterns, because it yields to bettercharacterization of vegetative cover. Yet a comprehensive and continuous monitoring ofvegetative cover of rangelands has not been established. To study the influence of droughtinessand wetness on vegetation cover and production forage, 11 sampling areas and 3 referenceareas were selected in Herat. Three 100-m transects were located 25-m apart within eachsampling area. Production and cover were estimated within 10 located 2- plots along eachtransect. Data were analyzed using Duncan›s test Design a completely random with a factorialGLM procedure at 99% and 95% confidence levels. Results showed that the vegetation coverand 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 wetnesscompared to the droughtiness. The influence on production and cover was positive and efficientin the wetness with the average rainfall higher than the 30-yr average. Finally, the results offlood spreading increased vegetation cover and production forage in dams.
