جستجوی مقالات مرتبط با کلیدواژه "آبخوان داری" در نشریات گروه "آبخیزداری، بیابان، محیط زیست، مرتع"

Watershed management is one of the most efficient methods of sustainable land management. In the current research, was evaluated the economic and social effectiveness of implementing watershed projects in the Gelevard sub-basin, Nekarud watershed, Neka city. The statistical population of this research included 2775 households and the sample size was 280 household heads. Data analysis was conducted using SPSS software. The results showed that the effectiveness of watershed management measures in preventing the reduction of flood damage and the level of satisfaction with the mechanical and biomechanical operations implemented in the study area have the highest priorities in terms of average rank. Correlation coefficients (R2= 0.60, P-value= 0.01) examination showed a high correlation between the implementation of watershed management operations and creating incentives for the residents of the village to stay in the village and reducing migration from the village. The results of the Kruskal-Wallis test showed no significant difference (Chi-square-1.32, P-value=0.72) between the effect of watershed management activities on improving people's living conditions in relation to the way of participation and the type of participation of the respondents in executive measures. Summarizing the results of this research showed that watershed management activities in this watershed improved people’s living conditions, increased the motivation of village residents to stay in the village, and reduced migration.

One of the most common and conventional methods of artificial feeding of aquifers is the flood spreading method, which feeds underground water tables, increases the quantity and quality of vegetation, and improves the soil of the plains. This study aimed to investigate the effect of flood spreading on the process of quantitative changes in vegetation cover and the effects of flood spreading on the soil seed bank in the Sarchahan flood-spreading area of Hormozgan Province over a 25-year period (1996–2022). Sarchahan flood dissemination station is located 90 km north of Bandar Abbas. The investigation method was such that the flood-spreading area of Sarchahan was chosen as a treatment, and a similar area in its vicinity was selected as a control in terms of vegetation and soil, which only had silage. In this research, 4 irrigation networks and three dams, in each network (flood spreading area) and 3 transects in each dam and 10 plots of 4 m2 in each transect to measure different vegetation parameters as sampling units within the flood spreading system in a random systematic way and the same number of transects and plots in the non-drained field were selected as witnesses and measurements and statistics were carried out. In order to check the seed bank, soil samples were taken from 20×20 cm microplots and from 0 to 5 and 5 to 10 depths from the four corners and the center of each plot. Soil samples were planted in the greenhouse of Hormozgan University to check the seed bank, and after germination and identification of plant species, all vegetation cover and seed bank data were analyzed with the help of SAS software. The results showed that the effect of flood spreading on the coverage percentage, production rate, litter percentage, rock and gravel percentage, density per hectare and sediment depth was significant at 1% level and the coverage percentage, production rate, litter percentage, density per hectare and sediment depth in the control treatment were 19.56, 42.6, 1.49%, 5438 bases, and 0.64 cm respectively after flood spreading operation, respectively. 2, 3.9, 2.8, 2.6 and 17.3 times increased. A comparison of the average biological indicators of vegetation in the first and second soil depths among the different treatments using the independent t-test at the 95% level showed that the biodiversity of vegetation in the first and second soil depths at the flood-spreading site was more meaningful than witness that of the witness site. Simpson and Shannon's biodiversity, Sheldon's and Brillion's uniformity indices, and Menhinick's and Margalf's richness index were significantly higher than the control at both depths in the flood spreading site.

Nowadays, urbanization and increasing construction and industrialization of cities in developing and developed countries have led to reduced permeable surfaces, climate change, and excessive use of and demand for surface and subsurface water resources. Therefore, most cities have faced phenomena such as severe floods, scarcity of surface and subsurface waters, land subsidence, dust and so on. In addition, the inefficiency of traditional flood management strategies has resulted in massive floods in cities, causing extensive financial and life losses, inundation, and heavy traffic in these areas. Aquifer and watershed management are among the environmentally friendly ways that manage floods, in addition to controlling them, and solve the problems to a great extent by the integrated management of surface and groundwater resources. In this study, an integrated flood management approach is applied on the basis of the aquifer management criteria using GIS software. Then, the weights of the criteria are calculated using the fuzzy method (fuzzy AHP) of Chang, Buckley, and Mikhailov, and the above steps are performed for the classical method of hierarchical analysis as well. Based on the prioritized 15 sub-basins of the 22nd district of Tehran as well as the mean squared error (MSE), it turns out that all the 4 methods show the priorities 1 to 4 alike, and the differences among them are in the other 11 sub-basins. The results of the MSE method also show that the criteria weights in Mikhailov's fuzzy method are closer to those of the classical method, and among the fuzzy methods the weights calculated from the Buckley and Mikhailov’s methods are closer to each other.

In arid and semi-arid regions of the world including Iran, floodwaters are the main resource to supply irrigation water. Floodwater spreading also plays an effective role in replenishing groundwater, stabilization of alluvial soil, and vegetation restoration. Qazvin traditional garden is an example of such floodwater spreading mechanism, dating back to over a thousand years ago, according to historical sources. The city of Qazvin is located at the foothills of the Aborz ranges and on the alluvial fan of the seasonal rivers. The traditional garden was built as a protective green belt around the city against floods. These unfenced gardens have been established as the largest aquifer in the region and an efficient flood spreading system to protect the city against floods. The gardens cover a vast area of around 2500 ha on three sides of the city. The unique practice of floodwater irrigation stabilizes the alluvial soil and recharges water in underground reservoirs. The gardens are placed next to each other in the form of ponds and are separated by borders with a height of about one meter. During the rainy season, the gardens are alternately filled with water up to the height of the ponds, which allow the water to infiltrate gradually into the soil. Almond, pistachio, and grape trees are irrigated once or maximum twice in months with very low evaporation. With such little irrigation, these trees survive and have economic efficiency. It is expected that the unique floodwaters irrigation of Qazvin traditional garden achieves its status in the strategic priorities of water management in the province.

Kowsar Floodwater Spreading, Aquifer Management, Training and Extension Station was established in 1982 on the Gareh Bygone Plain at 1140 m above sea level. The area has an arid climate and is located 190 km southeast of Shiraz, Iran. Thirteen floodwater spreading systems, covering 2445 ha, were designed and constructed during the 1983-2003 period to artificially recharge groundwater. Eucalyptus and Acacia species have always been considered for plantation in arid areas due to their drought resistance, flexibility in harsh habitat conditions, and the use of their wood and other by-products. Results of previous field experiments showed that E. microtheca, A. salicina, A. victoriae, E. oleosa, and E. camaldulensis were very successful, with more than 80% survival at the station. Therefore, more than 600 hectares of extensive and 100 hectares of intensive forest plantations with Eucalyptus and Acacia species have been established in the region.  Using the clipping and weighing method and organic carbon measurements in the laboratory, carbon storage capacity in Eucalyptus and Acacia forests at the station was estimated to be 7.8 tonnes/haannually. The average total dry biomass of E. camaldulensis trees in this area during the study period (16 years) was 247.07 tonnes/ha, of which 136.66 tonnes were trunk timber, 46.72 tonnes were leaved branches, and 39.94 tonnes were bark. Eucalyptus species flower twice a year in this area, providing  a source of pollen and nectar throughout the year for beekeeping. The average honey production at this station was 11 kilograms/hive. Moreover, the area attracts many eco-tourists, particularly during the holidays because of the beautiful landscape of the forest in a desert region. As Eucalyptus species use large amounts of water, it is proposed to replace these species with less water-demanding trees.

Groundwater vulnerability is due to the inherent vulnerability and characteristics of the occurrence of contaminating sources and human-induced pollution. Sixty four quality measuring wells, 20 observation wells and more than 28000 operating wells were sampled in order to provide vulnerability maps for 2004 and 2014. The essential factors of the inherent vulnerability included hydraulic conductivity, aquifer type, distance from the coast, and aquifer thickness. Additional factors of specific vulnerability including well density, decline of groundwater level, relative impact of seawater intrusion, condition of saltwater up-coning and hydraulic gradient were also used. The results indicated that the quality of groundwater resources had declined from 2004 to 2014 according to salinity criteria such as electrical indicated by an increase in conductivity (EC), sodium absorption ratio (SAR) and total dissolved solids (TDS). The land use factor was also used to prepare modified vulnerability maps for the year through 2004-2014. The results indicated that while the irrigated area had decreased by 8 percent during this period, the level in high-vulnerability areas had increased, which may be surmised that an increase discharge rate and double-cropping had caused degradation of the groundwater. The results showed that the mean correlation coefficient of vulnerability to salinity classes with salinity criteria such as EC, TDS and SAR had improved in 2004 from 0.65 to 0.9, and in 2014 from 0.78 to 0.87. Duo to the complexity of qualitative modeling, solute transport and groundwater salinity, the modified vulnerability maps is a good tool to predict the impending groundwater salinization.

Due to lack of surface water, the most important option for water supply in arid and semi-arid areas is from groundwater resources and one of the engineering measures to use the floods for improving groundwater resources is the implementation of artificial recharge systems. The purpose of the present study is to provide a model-based framework based on several quantitative indicators such as recharge efficiency and flood attenuation rate for assessing the performance of artificial recharge systems. Considering the capabilities of hydrological, hydraulic and seepage models, the combination of these models was used to estimate the parameters of the indicators. Finally, by determining the indices for floods with different return periods, their average values were determined using the expected value. The studied system (Emamzade Abdollah, Sorkheh) had a good performance based on recharge efficiency and flood attenuation rate indicators in events with frequency of more than 0.2, and the average value of these two indicators was 0.54 and 0.93, respectively. Due to the model based characteristic of the proposed framework, it has the potential to be used in similar cases.

Flood water spreading (FWS) is one of the water resources management strategies in arid and semi-arid regions aiming at water harvesting, artificial aquifer recharge and optimum utilizing of floodwater. There are three kinds of drops (gates); vertical and inclined (type 1 and 2), as the main structure of a floodwater spreading system which is susceptible to collapse due to flooding damages. In this research, one of the independent systems of FWS was selected in Kowsar research station in Gareh Bygone, Iran in order for evaluation of technical and economic analysis of drops’ collapse. The study is performed by direct observation and fieldwork. Results show that the main causes of collapses are erosion of embankment, piping of drop and instability collapse of side walls. Contrary to even of flood discharge of Bisheh Zard1, at flood events in 2003, the results show that the amount of destruction in an inclined drop is more than the vertical drop. Inclined drop 1 and vertical drops are the less and the most expensive, respectively. Therefore, inclined drop 1 might be recommended for being widely used due to maximum stability and minimum costs (the ration of 0.6 between the costs of inclined 1/vertical drops).

In most projects of watershed management، studies are necessary for monitoring، evaluation and comparing the parameters with the indices in projects. In water spreading projects there is such a necessity for measure، process and evaluate obtained information from performance results. According to the important role of aquifer management in rangeland improvement، as a new method، the purpose of this study is investigation and evaluation of flood spreading effects on vegetation cover changes and status and trend of rangeland during 2000 to 2004 years. In this study، two areas of flood spreading and testimonial control points were selected. Flood spreading network consisted of five strips and 12 fixed plots (2×2 m) were chosen in each strip with random-regular method. A testimonial area was selected to evaluate the results with eight plots similar to flood spreading areas. Results demonstrated that the status of rangeland condition in testimonial area was very weak and in flood spreading area was very weak to weak and was changing from to moderate condition. The trend of rangeland in testimonial area was negative while in flood spreading area was positive. Also، results showed that the forage production were 144. 3 and 113. 6 kg per hectare in the first year and 224. 5 and 202. 3 kg per hectare in the last year، in flood spreading and testimonial areas respectively.