نتایج جستجو برای: can estimate the soil erosion andamount of load sediment

تعداد نتایج: 22864603  

Journal: :تحقیقات جغرافیایی 0
محمود حبیب اللهیان دانشگاه حکیم سبزواری احمد نوحه گر دانشکده محیط زیست دانشگاه تهران علیرضا کمالی منابع طبیعی محمود حبیب اللهیان دانشگاه حکیم سبزواری معصومه رخبین پردیس دانشگاهی قشم دانشگاه هرمزگان احمد نوحه گر دانشکده محیط زیست دانشگاه تهران

â increase in wastage of soil resources in watershed is a persistent challenge that with increase in population and pressure on natural sources and unstable plantation on gradient farms and soils cause production reduces on farms, and also decrease in daily ratio of farms to population can cause more pressure on lands and natural resources.lavarefin watershed placed in 60 km from bandarabass in...

Journal: :اکو هیدرولوژی 0
محسن خورسند دانشجوی کارشناسی ارشد، گروه مهندسی آبخیزداری، دانشکدۀ منابع طبیعی دانشگاه تربیت مدرس، نور عبدالواحد خالدی درویشان استادیار، گروه مهندسی آبخیزداری، دانشکدۀ منابع طبیعی دانشگاه تربیت مدرس، نور مهدی غلامعلی فرد استادیار، گروه محیط زیست، دانشکدۀ منابع طبیعی دانشگاه تربیت مدرس، نور

the presentstudy aimed to compare the annual soil loss prediction of rusle model with the soil erosion measurements using erosion pins and plots in khamesan representative watershed, kurdistan province. for this purpose, the distributed annual soil loss was estimated by rusle model. the suspended sediment samples were then collected daily for one year (2015/7 to 2016/6) in hydrometry station at...

Extended abstract 1- Introduction The phenomena of erosion, sediment transport, and sedimentations have tremendously destructive effects on the environment and hydraulics structures. In general, the sediment transportation depends on river discharges, but the proposed equations inherited serious errors.  The estimation of suspended sediment load (SSL) is one of the most important factors in r...

Soil erosion and sediment yield from watersheds confine sustainable use of land resources and is supposed as one of the most critical environmental issues. Prediction of storm wise soil erosion and sediment yield is very important, especially in arid and semiarid regions due to small number of events and high intensity of rainfall. Evaluation of soil erosion by existing models is needed as an i...

Extended abstract 1- Introduction      Soil erosion, as one of the most important environmental problems in the world, has a devastating effect on all life, natural resources and it's under human management. Considering that one of the important goals in the management of drainage of basins such as Gabric basin is preventing soil erosion, and also one of the important factors when designing d...

One of the important parameters, that reduce negative influence of the other known parameters, is cover vegetation. In this study were estimated cover vegetation influence in soil erosion of Razin basin in Kermanshah province that is our study area. The first step is preparation map of NDVI obtained & category of cover vegetation by the Landsat TM data. Then Revised Universal Soil Loss Equation...

Journal: :environmental resources research 0
a zare gariz phd candidate, department of rangeland and watershed management, yazd university, iran a talebi associate professor, department of rangeland and watershed management, yazd university, iran

in this study, the process-based watershed model, soil and water assessment tool (swat), was used for simulating hydrology and sediment transport in the gharesou watershed and for identifying critical areas of soil erosion and water pollution. after model calibration and uncertainty analysis using sufi-2 (sequential uncertainty fitting, ver. 2) method, the outputs of the calibrated model were u...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه صنعتی اصفهان - دانشکده ریاضی 1390

abstract: in the paper of black and scholes (1973) a closed form solution for the price of a european option is derived . as extension to the black and scholes model with constant volatility, option pricing model with time varying volatility have been suggested within the frame work of generalized autoregressive conditional heteroskedasticity (garch) . these processes can explain a number of em...

Extended abstract 1- Introduction The Soil surface characteristics have significant effects on the erosion process. The wide areas of watershed soil surfaces are covered with considerable amounts of rocks and pebbles. Surface rock fragments, resulting in water connectivity, change during the erosion process. Rock fragments on the soil surface may increase the infiltration and reduce soil loss...

Journal: Desert 2012
H. Ahmadi M. Jafari M. Nasri S. Feiznia

The problems of land degradation and soil loss are among the major problems of watersheds in Iran. For erosion andsediment estimation one can use statistical and empirical methods. For doing this, land unit map and the map of effectivefactors should be prepared. For erosion and sediment estimation one can use statistical and empirical methods. However,these empirical methods are usually time co...

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