مجله ترویج و توسعه آبخیزداری
پیاپی 21 (تابستان 1397)

Today, the assessment of water management projects is one of the most fundamental issues that are being addressed in countries in order to implement future plans and manage natural resources. In this study, in order to evaluate the watershed management operation, the executed and predicted watershed management operations in Mokhtaran watershed were compared according to the year and type of implementation. According to the foreseen activities for all sub-basins, during the years 2007 to 2011, the biological operations were only implemented for the sub-basins M21 and M22 regardless of their prioritization. Furthermore, during the years 2007 to 2011, mechanical operations were only executed in the sub-basins M21, M22 and M41 which were in conflict with the type of previously foreseen structures for the sub-basins. Results showed that in the comprehensive studies there is not a special attention to the socio-economic considerations of available constraints within the studied basin. The shortage of developmental budgets has also been another main factor behind the lack of agreement between implemented and anticipated watershed management operations. During the last 6 years, the amount of developmental budgets has been closed to zero. The low population density of the Mokhtaran basin was another reason for not implementing the planned watershed management activities. Therefore, in order to reduce the inconsistency and difference between the projected and implemented activities in the watershed, the following measures should be considered: 1- Given that it is not possible to accomplish tasks due to shortages of manpower and resources at the same time in all sub-basins, the prioritization of sub-basins should be specified in the early stages. 2- In order to prioritize sub-watersheds, the use of precise and mathematical prioritization methods such as fuzzy-topsis is recommended. 3- The need for a comprehensive approach for prioritizing and selecting the type of watershed operation is indispensable to reduce the degree of contradiction between the activities planned and the implementation of the activities. 4- Due to the lack of development budgets and low population density in the area, comprehensive management of watersheds should include the study and recognition of all technical, economic and social aspects of the area in order to prevent the waste of watershed resources and achieve the watershed management objectives.

In terms of climatologists and atmospheric air and sociologists who have studied climate change in a global perspective snow monitoring is a necessity. Because the physical properties of the snow on daily changes in climate and even change the effect of long-term climate-leaves. The study measured changes in snow surfaces as an important source of water supply is very important. Due to the possibility of measured environmental conditions mountain snow and the establishment of permanent land for resource estimation database does not exist. Using satellite images to identify and characterize changes snowy areas is very important. In this study, MODIS satellite imagery Chaharmahal Bakhtiari Province within the period between 2007 and 2015 and for the month of March, December, January, February, April and was elected. Results During the study period showed reduced levels of snow that can be reduced as a result of global climate change and global warming.

Nowadays, water quality is one of the key issues in most regions all over the world. Because of its high relation with human health and also have important role in management and exploitation of resources. This research has done first time in Pasargad city located in 105 km of eastern north of Shiraz. In order to determine drinking water quality factors using data mining technique, results of this research have obtained using Quest decision tree in Clementine software(12 version) and showed most effective factors of drinking water in this region is function of total harness and electrical conductivity. In this way, if total hardness in this city is less than 282.232 parts in million and electrical conduction is less than 822.787 micro mohs in centimeter, this water will be suitable for drinking. Therefore recommended more noting to refine and decrease the hardness of water for human drinking water, moreover continuous refining in periodically regular sampling of water resources in this city should be noted.

Application of continuous hydrological models and its calibration methods development using geographic information systems are increasingly expand. The purpose of this study is calibration and validation of SMA model and simulation of continuously river flow in Neka basin. In this study, firstly the temperature and precipitation variables prepared for the model and then SMA parameters were calculated for different period of calibration. The parameter estimates needed analyzed in GIS for the different period and finally validation and its accuracy was estimated. Generated hydrograph from the scenarios set of model parameters was compared in Gelvard observation station. Annual calibration and validation results showed that the observed and simulated correlation coefficient was 0.80 and 0.75, respectively. Also, for the validation period the objective function of AEPM (10.17) had a better matching than the calibration period (18.26). By simulating the flow river using climatic events which continuously over a long period of time, the daily discharge is obtained and showed the satisfactory results. Using this model for estimating of stream flow, the study of climate change, changes in land use and therefore better management of water resources is possible.

Analysis of measured soil erosion data and its variability are critical for advancing erosion science, evaluating soil erosion models, and designing erosion experiments. The present study aimed to evaluate the measured sediment yield data at micro-watershed in Iranian semi-arid rangeland. Towards this attempt, five micro-watersheds with different size (1000 m2-17000 m2) were gauged in Sanganeh watershed, Khorasan Razavi Province, Iran. Storm-wise runoff and sediment was collected at the outlet of each watershed. In this study, sediment yield from micro-watersheds for 55 events over the years 2006 to 2016 were compared and evaluated. The results showed that the maximum of sediment yield were transported in spring due to high rainfall intensity, sediment availability and insufficient vegetation growth. The results also, indicated that mean sediment yield can be changed by a single event (high return period), because approximately a 50% of the sediment yield is produced by only a 7.3% of events. Finally, in current study, a decreasing non-linear relationship between special sediment yield and watershed size was founded.

Measuring deposited sediments behind small dams, large dams, and other reservoirs is essential in many research and development projects. Unfortunately, there is no guide for sediment surveying in reservoirs that are dry for some times every year. In this paper, these reservoirs are divided into three classes and methods for surveying sediment volume and weight was explained based on author's experiments countrywide by providing examples, figures and photos. Some important points on measuring siltation depth and determination the boundary of coarse-grained (delta) and fine-grained deposits (lacustrine sediments) and their contribution in total sedimentation were described in this section. Determining the bulk density is required to calculate the sediment load, which is subsequently described in more detail. This section first explains sediment stratification method in the control profiles and then describes two methods for measuring bulk density. In the following section, technical considerations on measuring sediment cracks to correct bulk density and finally calculating sediment weight are given.

In this study, daily rainfall-runoff simulation were discussed during 2000-2005 Khormaloo, Gharechay, Chehelchay Rivers in Golestan province using adaptive neuro-fuzzy inference system (ANFIS). First separate base and surface flow using a recursive digital filter. First separate base and surface flow using a recursive digital filter. Then using discharge in antecedent days and meteorological parameters such as temperature and rainfall, base and surface flow simulated separately using ANFIS and the best entries were determined. Total flow was determined by combination of best model of base and surface flow by ANFIS. The results of the combination of base flow and surface flow models and finally total flow modeling showed in all three stations, the model that combination of base flow and surface flow on before day has highest coefficient of determination and minimum error. Coefficient of determination in the test phase for Nodeh Khandooz, Ramian and Lazoore stations is 0.691, 0.991 and 0.999 respectively and error in stations is 1.413, 0.131 and 0.036 respectively. The results showed that the use of separation base flow technique increase the speed and accuracy of simulation and eliminates the problem of low speed execution in ANFIS and base and total flow predicted accurately.