نوع مقاله : مقاله پژوهشی
1 دانشجوی دکتری علوم و مهندسی آبیاری، دانشکده کشاورزی، دانشگاه فردوسی مشهد
2 استاد دانشکده کشاورزی، دانشگاه فردوسی مشهد
3 استادیار پژوهش، مرکز تحقیقات کشاورزی خراسان رضوی
4 مربی آموزشکده کشاورزی، دانشگاه فردوسی مشهد
5 کارشناس ارشد خاکشناسی، دستیار تحقیق
عنوان مقاله [English]
Modeling water flow and solute transport in unsaturated zone requires knowledge of soil hydraulic properties such as water retention curve. Indirect determination of these functions from basic soil properties using pedotransfer functions (PTFs) has attracted the attention of researchers in a variety of fields. Nowadays using of ANNs models for PTFs deriving is very usual. In this research we introduced and evaluated new pseudo pedotransfer functions and compared with point and parametric pedotransfer function. Also impact of two different method of training, direct and indirect was calculated. All the calculation is done on 122 soil samples of north and north east of Iran that were selected randomly. Generally result of parametric functions was better than point functions. The average of r and RMSE indicators in parametric functions are 0.93 and 0.032 and in point functions are 0.76 and 0.034. On the other hand pseudo parametric functions improved the results of point functions with using the same information’s for training. The average of r and RMSE indicators in pseudo parametric functions are 0.95 and 0.026. It seems that increasing of samples in training phase and select the matric potentials as input are the most important factors in pseudo parametric functions success. Also results show that using local data for deriving pedotransfer functions (direct training) is better than using universal data base (indirect training).