maryam etehadi abari; a a; a a; meghdad jur gholami
Abstract
Land cover is also important factor for protecting the soil against erosion. A fully forested watershed experiences relatively little surface erosion, but timber harvest alters the canopy cover, exposing the soil to water and wind. Forests provide the maximum amount of soil protection. Reduction of vegetative ...
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Land cover is also important factor for protecting the soil against erosion. A fully forested watershed experiences relatively little surface erosion, but timber harvest alters the canopy cover, exposing the soil to water and wind. Forests provide the maximum amount of soil protection. Reduction of vegetative cover by forest harvesting generally increases the average surface runoff volume and sediment While, the hydrologic response of forest harvesting has been rarely considered. Towards this attempt, the present study has been conducted to investigate the effect of vegetation cover on hydrological components in plot scale (2m*1m) with four replicates in tow slope scale (0-20%, 20-40%) in Kheyrud Forest of Iran during December 2014 until December 2015. The rain depth was measured by using a rain gauge installed in the study area. The runoff volume and sediment yield were also measured through field data collection and lab analyses by weighting and decantation methods. The results of the study showed significant effects of vegetation cover (P ≤0.01) on runoff volume and sediment yield. Natural forest without harvesting, forest with selective harvesting treatments exhibited the lowest amounts of runoff and sediments, with averages of 372.31, 878.96 cc, and 0.08, 0.17 gr m-2 respectively, in comparison to other treatments. Linear regression among mentioned parameters (precipitation, runoff, and sediment) were determined. The results show that there were significant correlation and linear regression among precipitation, runoff and sediment.
Azam Tabarzadi; Meghdad Jourgholami; Alireza Moghaddam Nia; Baris Majnounian Garagiz; Pedram Attarod
Abstract
Many environmental challenges such as stormwater runoff and flood risk, chemical and particulate pollution of urban air, soil and water, the urban heat island, and summer heat waves are exacerbated in urban environments. Runoff from heavy rainfall in many parts of the world lead to erosion, sedimentation ...
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Many environmental challenges such as stormwater runoff and flood risk, chemical and particulate pollution of urban air, soil and water, the urban heat island, and summer heat waves are exacerbated in urban environments. Runoff from heavy rainfall in many parts of the world lead to erosion, sedimentation and transportation of elements that forest covers is the most important factor in controlling it. In this research, the qualitative and quantitative characteristics of runoff in Chitgar forest park have been investigated. For this purpose, runoff discharge, physicochemical parameters including total suspended solids, total dissolved solids, pH, and chemical parameters including calcium, magnesium, sodium, potassium, nitrate and phosphate were measured and analyzed during three storm events. The results of the present study indicated that the average values of the measured parameters were 1988.3 l / h, 40.64 mg/l, 2064.8 mg/l, 7.75, 2.95 mg/l, 2.23 mg/l, 584.4 mg/l, 5.71 mg/l, 1.36 mg/l, and 0.71 mg / l. Also, the correlation between parameters showed that there was a strong relationship between measured parameters, with the highest correlations between calcium with discharge (0.66) and total dissolved solids (0.69) and sodium with pH (0.7) and total dissolved solids (0.65). Comparison of the results obtained from this study and with those of other studies on water quality status of different rivers indicates that the qualitative pattern of urban runoff and also the relationships among the qualitative parameters of urban runoff are very different from surface runoff of rivers.
Meghdad Jourgholami; Vahid Rizvandi; Baris Majnounian Garagiz
Abstract
Assessment and management of the environmental impacts of forest harvesting operations have become increasingly critical factors in practicing commercial forestry. This study investigated soil disturbance from a forest logging system operation on an 8-hectare mixed broadleaved stand in compartment no. ...
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Assessment and management of the environmental impacts of forest harvesting operations have become increasingly critical factors in practicing commercial forestry. This study investigated soil disturbance from a forest logging system operation on an 8-hectare mixed broadleaved stand in compartment no. 309 in Gorazbon district in Kheyrud educational and research forest. The objective of this study was to assess soil disturbance from ground-based skidding system operation contribute to statistically significant changes in bulk density and penetration resistance at various depths below the soil surface and changes in bulk density and penetration resistance related to different traffic intensities. A systematic predetermined grid that was laid out prior to harvesting to measure soil disturbance, and pre-and post soil disturbance were recorded by a visual assessment. Soil compaction and penetration resistance were measured by using a double sampling method consisting of a hammer driven hand corer and a hand-held soil penetrometer. Bulk density and soil strength measurements were taken at three depths: 10, 20 and 30 cm. Detrimental compaction was recorded for the soil bulk density results. Detrimental compaction was recorded for the soil penetrometer after medium and intense machine passes. Post-harvest detrimental soil disturbance wasn’t exceeded the USFS maximum allowable area that can be detrimentally impacted. Soil resistance results demonstrated no detrimental compaction in area to the skid trail center and wheel ruts.
