validation of shaw model in determination of maximum soil frost penetration depth in typical arid and semi-arid zones of iran
نویسندگان
چکیده
simultaneous heat and water model (shaw) is based on the assimilation rate of melting and/or freezing of the accumulated snow as well as melting of ice in soil. the main objective of this study was to evaluate applicability of shaw model in determining maximum depth of frost penetration in soils in some typical climates of iran. to this end, the daily data of air temperature, soil temperatures at different depths, duration of bright sunshine, and air humidity were collected for the period of 1992-2003 for four meteorological stations of iran including shahr-e- kord, urumia, sanandaj, and yazd. then, the maximum soil frost penetration depth (sfpd) for each year in the above mentioned stations was determined based on both the measured temperatures at different layers of soil and the calculated values using shaw model. results of the analyses indicated that there was a significant linear relationship between the observed and the calculated values of maximum sfpd. the obtained coefficients of linear correlation between the observed and the calculated values for meteorological stations of shahr-e-kord, urumia, sanandaj and yazd were 0.90, 0.77, 0.84 and 0.94, respectively, all being significant at one percent level. according to the results, it was concluded that, with the yearly records of weather parameters and soil conditions, a reliable estimate of the maximum annual depth of soil frost penetration can be made in similar regions of iran by application of shaw model.
منابع مشابه
Validation of air freezing index (AFI), for determination of frost penetration depth in typical arid and semi-arid zones of Iran
Depth of frost penetration is one of the main indices in agriculture, civil and transportation engineering. Soil temperature is a function of several factors including: topography, solar radiation, air temperature, moisture content and other physical properties of soil such as thermal capacity, coefficient of heat conductivity, and specific heat. The main objective of the present paper is to de...
متن کاملvalidation of air freezing index (afi), for determination of frost penetration depth in typical arid and semi-arid zones of iran
depth of frost penetration is one of the main indices in agriculture, civil and transportation engineering. soil temperature is a function of several factors including: topography, solar radiation, air temperature, moisture content and other physical properties of soil such as thermal capacity, coefficient of heat conductivity, and specific heat. the main objective of the present paper is to de...
متن کاملdetermination of maximal singularity free zones in the workspace of parallel manipulator
due to the limiting workspace of parallel manipulator and regarding to finding the trajectory planning of singularity free at workspace is difficult, so finding a best solution that can develop a technique to determine the singularity-free zones in the workspace of parallel manipulators is highly important. in this thesis a simple and new technique are presented to determine the maximal singula...
15 صفحه اولrole of cultural iran in promotion of multilaieralism in central asia and caucasus
cultural iran is a scope that is more extended than the political territories of iran as a political unit. this concept means that cultural geography(mehdi moghanlo-1383-1) of iran is greater than its political geography which, according to history, has a long history extending west-east from kandahar to the euphrates and north-south from the persian gulf to the caucasus including transoxiana a...
15 صفحه اولthe innovation of a statistical model to estimate dependable rainfall (dr) and develop it for determination and classification of drought and wet years of iran
آب حاصل از بارش منبع تأمین نیازهای بی شمار جانداران به ویژه انسان است و هرگونه کاهش در کم و کیف آن مستقیماً حیات موجودات زنده را تحت تأثیر منفی قرار می دهد. نوسان سال به سال بارش از ویژگی های اساسی و بسیار مهم بارش های سالانه ایران محسوب می شود که آثار زیان بار آن در تمام عرصه های اقتصادی، اجتماعی و حتی سیاسی- امنیتی به نحوی منعکس می شود. چون میزان آب ناشی از بارش یکی از مولفه های اصلی برنامه ...
15 صفحه اولPrediction of frost occurrence by estimating daily minimum temperature in semi-arid areas in Iran
ABSTRACT- Many fruits, vegetables and ornamental crops of tropical origin experience physiological damage when subjected to low temperatures. Protection of plants from the effects of lethally low temperatures is important in agriculture, especially in horticultural production of high value fruits and vegetables. The objective of this study was to develop a simple model to predict the daily mini...
متن کاملمنابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
journal of agricultural science and technologyناشر: tarbiat modares university
ISSN 1680-7073
دوره 14
شماره 5 2012
میزبانی شده توسط پلتفرم ابری doprax.com
copyright © 2015-2023