Mohammad Gheitury; Mosayeb Heshmati; Mohammad Roughani
Abstract
Water resources scarcity is the negative impact of climate change, which is more severe in arid and semi-arid regions, including Iran. However, harvesting water through micro-catchment is one of the possible issues for combating this problem. This research was conducted in Kaboodeh-Olya Village to compare ...
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Water resources scarcity is the negative impact of climate change, which is more severe in arid and semi-arid regions, including Iran. However, harvesting water through micro-catchment is one of the possible issues for combating this problem. This research was conducted in Kaboodeh-Olya Village to compare the effects of three different micro catchment systems on runoff harvesting and increasing soil moisture. The experimental plots were constructed at a 20% hill slope in northern direction. Research was carried out in randomized experimental block with tree replications. Micro catchments were constructed in rhomboid-shape (1.7×1.7 m) and treatments included plastic with pebble pavement (PPP), compacted surface soil with crop residue (CSCR) and control plot (CP) which was a natural surface soil. The harvested runoff from each plot was stored in a container with 100 litter capacity at the downward. The valium of overland flow was measured after each rainfall occurrence. Results demonstrated that harvested runoff rates through PPP, CSCR and CP were 88, 44 and 16 percent, respectively indicating significant effects (p<0.05) of both PPP and CSCR on runoff harvesting. Furthermore, the effective rainfall for triggering runoff at the PPP, CSCR and CP were 0.8, 1.5 and 3.4 mm that significantly was lower in PPP. Consequently, in limited CSCR building, the SSS can be used for maximum runoff harvesting and soil moisture storage.
Parviz Abdinejad; Mohammad Roghani
Abstract
The present research was carried out at a research station in Qarehchryan, located in north-west of Zanjan City, Iran. Rainwater catchment systems had dimensions of 5×8 m, with five treatments of control (withness)(A), without vegetation and gravel with gravelly filter (B),without gravelly filter ...
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The present research was carried out at a research station in Qarehchryan, located in north-west of Zanjan City, Iran. Rainwater catchment systems had dimensions of 5×8 m, with five treatments of control (withness)(A), without vegetation and gravel with gravelly filter (B),without gravelly filter (C), impervious a part of the system with gravelly filter (D) and without gravelly filter (E) in a randomized complete block design with three replications. There were nine daily rainfall events from April until late August 2013, with two times irrigation with an interval of 60 days, 45 liter for every seedling and 33 times of measurement of moisture at depths of 20 and 50 cm. Results showed that spring rainfall had not been able to produce runoff in the control treatments and had no effect on soil moisture. Soil moisture influence has been increased by daily rainfall in both B and C treatments compared to control treatments.. Soil moisture influence from daily precipitation has been increased up to 30 percent in D and E treatments due to insulating surface of existing systems and impervious surface of rainwater catchments. Timeline of the average moisture at the depths of 20 and 50 cm is almost similar in all treatments. This situation indicates that the distribution of moisture in depth of 20 to 50 cm is similar with no significant difference, but, the moisture at the depth of 20 cm is more than 50 cm.
Reza Chamanpira; Mohammad Roughani
Abstract
Evaluation is a fundamental tool for implementation of projects, and is used as a tool to assess their effectiveness. In areas with no evaluation, assessment is difficult. A practical method for overcoming to this problem is basin simulation using mathematical models. This research was implemented in ...
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Evaluation is a fundamental tool for implementation of projects, and is used as a tool to assess their effectiveness. In areas with no evaluation, assessment is difficult. A practical method for overcoming to this problem is basin simulation using mathematical models. This research was implemented in Dadabad Watershed in Lorestan, followed by impact assessment of watershed management operations on basin behavior change on reducing watershed area floods. Mapping and determining the volume of the built structures and their number, status, and characteristics constituted the first step of the research. The HEC-HMS mathematical model was then employed to estimate flood volumes. Results of simulations and comparison of the observed and simulated hydrographs indicated that the model had the required efficiency for simulating the Dadabad Watershed and was very sensitive to the parameters of curve number and initial loss. The capability of the storage ponds in storing runoff was then determined through calculating their volumes. The behavior of floodwater for the various return periods was simulated to determine the response of the watershed to design storms by applying the changes that had happened in the input part of the model. Results indicated that the water storage ponds could collect and store more than 80 percent of the runoff resulting from rainfalls with return periods of 2 and 5 years. In return periods of 10, 25, 50 and 100 years, 63.4, 54.3, 38.8 and 28.6 percent of the runoff stored in the ponds respectively, and the rest left the watershed from its outlet. In general, the water harvesting systems in the Dadabad Watershed could store 236645 m3 of runoff.
