نتایج جستجو برای: moisture retention curve

تعداد نتایج: 233029  

Journal: :iran agricultural research 2008
r. moazen zadeh b. ghahraman

the majority of hydraulic processes under a natural condition in a field are carried out under unsaturated flow conditions. the soil moisture retention curve (smrc) is the most important hydraulic characteristic of an unsaturated soil whose knowledge is of prime importance in soil-water studies such as soil conservation, soil erosion, land evaluation, soil reclamation, and water resources manag...

Journal: :آب و خاک 0
محمدمهدی چاری بیژن قهرمان کامران داوری علی اصغر خشنود یزدی

introduction: water and soil retention curve is one of the most important properties of porous media to obtain in a laboratory retention curve and time associated with errors. for this reason, researchers have proposed techniques that help them to more easily acquired characteristic curve. one of these methods is the use of fractal geometry. determining the relationship between particle size di...

Journal: :آب و خاک 0
موذن زاده موذن زاده قهرمان قهرمان فتحعلیان فتحعلیان خوشنود یزدی خوشنود یزدی

abstract pedotransfer functions (ptfs) are useful means of prediction many properties of the soil, and especially the hydraulic characteristics of this porous media. the main advantages of this functions, as compare to conventional methods used to directly estimate soil hydraulic properties, is that they are not time-cost consuming. different approaches such as classic linear and non linear reg...

Journal: :تحقیقات مهندسی کشاورزی 0
علی دیندارلو دانشجوی سابق کارشناسی ارشد علیرضا سپاسخواه استاد گروه آبیاری و زهکشی دانشکده کشاورزی، دانشگاه شیراز

solute transport processes are affected by soil pore water velocity distribution. pore size distribution, which can be used to infer pore water velocity distribution, can be estimated from a soil water retention curve (n). in this study, a solute breakthrough curve was simulated using soil hydraulic parameters in four different soils. to evaluate the proposed model, predictions were compared to...

Journal: :آب و خاک 0
موذن زاده موذن زاده قهرمان قهرمان کامران داوری کامران داوری خشنود یزدی خشنود یزدی

soil moisture retention curve (smrc) is an important soil property which expresses reaction between matric potential and moisture of soil. direct measurement of soil matric potential and moisture is labour- and time-consuming. in order to prevail this problem, indirect methods are used for smrc prediction. pedotransfer functions (ptfs) are one of these indirect methods. this study was carried o...

Journal: :تحقیقات مهندسی کشاورزی 0
فریبرز عباسی دانشیار مؤسسه تحقیقات فنی و مهندسی کشاورزی

soil hydraulic properties are key soil physical characteristics that are required to conduct soil and water related studies such as irrigation and drainage. in this study, three indirect methods: inverse modeling, pedo-transfer function, and the semi-physical method of arya et al., were compared in a sandy loam soil to estimate soil moisture retention and unsaturated hydraulic conductivity curv...

Journal: :پژوهش آب در کشاورزی 0
امید بهمنی استادیار دانشگاه بوعلی سینا. بهرام رمضانی دانشجوی سابق کارشناس ارشد دانشگاه بوعلی سینا.

soil water retention curve (swrc) is important in the studies of soil and water relationship, soil conservation, irrigation scheduling, drainage, solute transport, plant growth and crop water stress. the performance of 10 models (simons et al., libardy et al., campbell, farrell and larson, van genuchten, brooks and corey, driessen, exponential bruce-luxmore, power bruce-luxmore, and rogowski) w...

Journal: :تحقیقات مهندسی کشاورزی 0
حسین احمدی چناربن استادیار دانشگاه آزاد اسلامی، واحد ورامین – پیشوا، گروه زراعت و اصلاح نباتات سعید مینایی دانشیار گروه مهندسی مکانیک ماشین های کشاورزی دانشگاه تربیت مدرس علی رضا بصیری استادیار گروه مهندسی شیمی موسسه تحقیقات و پژوهش های علمی و صنعتی ایران مرتضی الماسی استاد گروه مهندسی ماشین های کشاورزی و مکانیزاسیون دانشگاه آزاد اسلامی واحد علوم و تحقیقات تهران اکبر عرب حسینی دانشیار گروه مهندسی مکانیک ماشین های کشاورزی پردیس ابوریحان دانشگاه تهران

varieties of st. john’s wort (hypericum perforatum l.) native to iran possess the largest percentage of hypercin in their leaves and flowers. isotherm curves show the relationship between the relative humidity and moisture content of the plant at a constant temperature. it is essential to understand the isotherms curves for successful storage and drying of the plant. this study used adsorption ...

Journal: :مدیریت آب و آبیاری 0
مجید هماپور گورابجیری دانشجوی سابق علوم خاک، دانشکدۀ فناوری کشاورزی، دانشگاه محقق اردبیلی علی رسول زاده استادیار گروه مهندسی آب دانشکدۀ فناوری کشاورزی دانشگاه محقق اردبیلی

soil water retention curve is one of the crucial input parameters in any modeling study on water flow and solute transport in soils. direct measurement of soil water retention curve is time-consuming and costly. alternatively, pedotransfer functions (ptfs) may be used to indirectly estimate the soil water retention curve from easily measured soil properties. many equations for the soil water re...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید