nowadays protecting land cover, quality and quantity of water resources are important. surface runoff is one of most important reasons of soil erosion which causes sediment in reservoirs and reduction of land’s fertility and also quality reduction water of rivers. so the main issue is exact prediction of basin runoff to raining events. the hydrologic models are simplified models of real hydrolo...

this experiment aimed to determine evapotranspiration, and responses of some yield and quality parameters of subsurface drip irrigated broccoli (brassica oleraceae l.). treatments included water application when available soil moistures were depleted 30, 40, and 50% during both spring and autumn cultivations. under a semi-arid climatic condition of tokat, turkey, the experiment was carried out ...

We present a novel method for simultaneously phase matching several nonlinear optical interactions within a single crystal. Quasiperiodic modulation of the nonlinear coefficient enables one to achieve high frequency mixing efficiencies for interactions with arbitrary wave vector differences. Doubling of two different frequencies as well as direct frequency tripling is experimentally demonstrate...

there is a lack of accurate and correct information about erosion in iran. moreover, there is a big difference between measurements and estimations. sediment is also an important environmental problem which pollutes water physically and chemically and therefore, sediment problem is usually studied as environmental problems. estimation of sediment yield of drainage basins is important for preven...

due to the scarcity of water resources, the need for sustainable development of drip irrigation tape is essential in iran. a number of drip irrigation tape systems used in sugar beet fields of isfahan and chahar mahal va bakhtiari provinces were evaluated and were compared with furrow irrigation methods in two consecutive years. the actual water use efficiency (wuesy, wuewsy) in lower quarter, ...