مجله سامانه های سطوح آبگیر باران
سال دوم شماره 1 (پیاپی 2، بهار 1393)

In the Hormozgan province، limitation of fresh water resources has led the people of ancient times to think collected and stored rainfalls. Local people and invaders to the store fresh water، build ponds and wells in the area. In many villages، districts، centers and smaller cities in Hormozgan porovince، the pool is still the only source of drinking water. Rainwater is collected and stored in ponds for drinking is very important. Ponds in the south of Iran have certain characteristics and effects. Recently، the towns and villages develop and have piped water systems، but a major expansion of ponds around the villages and roads are visible and the pond water is used for drinking. According to statistics provided by the Health Center of Hormozgan province، there are existing 2842 water reservoirs or ponds in the province. The volume of water extracted from these ponds is more than 15 million cubic meters. Today، people have tried to prevent water pollution and its quick steering ponds، rainwater harvesting levels as high as nearby pond that is steeped expand. These surfaces are called Mamar in local term and they are made of stone and cement. A prominent example of such structures can be seen in the Anjireh village، Bandar Lengeh، Hormozgan province. People of Lavar Sheikh Village''s addition to building ponds، have been built concrete short dams in narrow valleys upstream and in this way to collect and store runoff. Water collected in the form of gravity led to the village and are used for drinking consumption. Peoples of Bavrdan village have done very interesting initiative to collect and store flood waters using indigenous knowledge and modern science. They have led floods with good quality to a recharge pool that has a very simple form and a small groundwater aquifer have created. A number of wells have been drilled in the recharge pool and the stored water is extracted through wells and used for drinking. All of them are shown that People looking to use local knowledge and combining it with the knowledge of today and the reason is the need for fresh water and drinking.

Today، water supply is a critical issue in developing countries. Collecting rainwater from the roofs of buildings in urban areas for unsanitary and irrigation purposes is possible and help resolve the water crisis of citizens. If roof pond surface system of houses are modeled and simulated according to local daily precipitation statistics، percent of the water needs of residents،، the area of rainwater harvesting، running costs of the system and are designed and performed based on results obtained from charts and graphs، it causes increase the efficiency of these types of systems in urban areas. In this study، rain pond surface System and the performance of tanks for storing rainwater and the daily water needs of the residents in the buildings in Rasht is analyzed based on daily precipitation statistics from 1338 to 1386. According to these results، it can be said that if the volume of tanks and daily unsanitary needs of residents are calculated based on the physical and hydrological condition of the building، Rainwater storage in tanks reaches the maximum and there are more days for providing unsanitary needs of the residents by collecting rainwater. In Rasht، 80% and 50% of all days of the year، the daily unsanitary needs of determined residents can be provide by using large and small tanks respectively.

Ali Akbar Abbasi، Ali Bagherian Kalat، Elham Khoshbazm Email: ak_abbasi@yahoo. com Abstract The water shortage in the world is one of the main problems that affect human life especially in arid and semi-arid area. Most area of the country is located within the arid and semi-arid. Rainfall in such areas is low with poor distribution that is causing droughts and water shortages. Catchments in mountainous areas produce runoff and plain areas in addition to direct rainfall; accumulate main part of mountainous water. Because of the steep mountain catchments have different hydrological behavior، the main characteristics of mountainous areas is producing water. If store the runoff or provide a suitable platform for its infiltration، In addition to providing water for pasture improvement or recharging of subsurface flow and groundwater، helps to reduce flood plain areas located at downstream. This research that has been done at Goosh catchment at the upstream of Kardeh dam، Evaluated the Impacts of low head structures on runoff maintenance and soil moisture. Based on field measurements، earth dams had the greatest role in storing runoff. After more than ten years due to the construction of watershed structures in the study area and deposition of fine sediments with depth of 1. 7 meters behind earthen dams، Which reduce the possibility of infiltration rate of stored water behind the structures. As a result، the major contribution of stored water has evaporation.

About fifty billions cubic meters of our land waste and financial loss and casualties due to them is more than milliards and ten، while nearly 90 percent of our land area is faced with water shortage. People in arid and semi-arid areas in order to supply the needed water for agriculture، drinking and domestic use have to use water from rainfall and run off. Intelligence of Homo sapiens has enabled him to adapt to harsh environments. Realizing that floodwater from ephemeral streams and flood is the only source of water available for irrigation، where rain -fed agriculture is nearly impossible; he has chosen floodwater spreading as the main stay of his life. The use of floodwater in Fars، Khorasan، Sistan and Baluchestan province are a good examples of using of floodwater and run off. Old traditional methods of rainwater and floodwaters harvesting come back to 3 to 5 thousand years. In spite of development of new methods for operation of the floodwater، nevereless the traditional methods in different areas are very good and efficient. Floodplain cultivation، floodwater harvesting by building micro catchments system in Stahbanat and Parezeition، Abanbar construction in Larestan، and micro catchments in Kelestan، Layzanganof Darab، Abesard are specific examples of harmony with harsh environment and optimization techniques of rainwater and run off harvesting in Fars province، that we will discuss about them in this article.

Because of existing rain deficiency in the arid and semi-arid areas، establishment the vegetation is being very difficult. Rain water harvesting systems (RWHS) can be used to help restoration of vegetation cover. Hand tools such as spade and peck can be used for making small RWHS. In order to investigate the effect of the proposed system، a diamond shape microcatchment has been constructed in Maravehtapeh region located in the east of Golestan province. The purpose of the implementation of this method was to examine the establishment of olive seedlings in a dry area as well as to determine the effect of different types of catchment cover. proposed catchment covers include: simple soil compaction، plastic cover supported with sand and natural (untouched) ground surface. The highest amount of runoff water was collected from plastic cover with runoff volumes of 1024 liter during one year measurement. This was three times higher than the ave. annual rainfall has happened in the region of investigation. Observations revealed the establishment of high yield olive seedlings at rainfed conditions.

Sand dunes of Iran with more than 4. 5 million hectare area as a feather of desert regions are important from different aspects. Sand dunes with special hydrologic characteristics، in addition to conserving humidity temporary suitable releasing it، capable to converting as a shrub lands or crop lands. Therefore، it is necessary to study water balance on sand dunes. In order to surveying on sand dunes vegetation capability in Sabzerar region using water balance، Dovlat-Abad sand dunes was selected as a fixed site for measuring of effective factors on water balance. Then، considering morphology of sand dunes، sampling and measurements were concentrated on two kinds of sand dunes (fixed & semi-active sand dunes). Continently، with attention to measuring moisture directly on reservoir horizon by TDR، soil profiles were distributed fitly on different slopes of sand dune. Then with recording monthly moisture and temperature data during 1381-1384 years and collecting meteorological data including precipitation & evapotranspiration using equation of water balance، sand dune was classified from hydrological view. Results showed that Dovlat-Abad sand dunes classified as Un–infiltrative sand dunes group. On this group، Gravitational infiltration is negative and nutrition of underground waters is impossible. So، at these sand dunes، precipitation is the major resource for requirement water of plants and the role of under ground waters isn، t important. Optimal exploiting of reserved moisture on sand dunes related on knowing range volume of it that studies indicated on sand dune situation in Dovlat-Abad، extra reservation of moisture nearly field capacity was occurred in winter season. With beginning of dry period، moisture was infiltrated deep layers. So، temporary date of seed or plantlet culturing with concentration of moisture on surface layers، provide conditions that minimum requirement water of plants was released and irrigation was restricted consequently water use of efficiency was increased.

Metropolises are facing water scarcity، particularly in arid climate. Rainwater harvesting as well as multiple use of water can help to overcome the water shortage problem in those cities. Water harvesting system can be employed for rain collecting. However، this system fails in arid regions during summers due to the lack of precipitation when most crops require more water. To overcome this problem، we suggested an innovative solution by adding a second sink in the kitchen to separate the rinse water from the water polluted with detergent. This improved system has successfully been tested in a four-story building in Karaj where led to a significant reduction of municipal water used for irrigation. The amount of harvested water is increased by an increase in the number of apartments in the building. In addition، this system decreases the rate of wastewater.

Runoff coefficient is a function of various parameters and geometric characteristics of the basin such as soil، vegetation، geology، sediment load and human factors which each of these factors can affect the amount of runoff at outlet of basin. However، rainfall is the main factor that affects the runoff. Runoff coefficient in large basin using rainfall data and flow data recorded by hydrometric stations is determined. In small basin because of lack of station، rainfall runoff coefficient and volume flow estimation is difficult. In this study، rainfall and runoff events in the Sanganeh Kalaat (the basin were small، with an area of about one hectare and a total area of approximately seven hectares) have been measured. Rainfall and runoff using a rain gauge and five runoff gauges has been recorded. Rainfall intensity is one of the factors that are effective in generating runoff. Hence، in this study، runoff coefficient with different intensities of rainfall has been examined. The results show that with increasing rainfall intensity، runoff volume has increased. Correlation curves between runoff volume and the area for different intensities of rainfall are presented that can be used to estimate runoff volume.