HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via ISI Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Mandal, U. K. Articles by Rao, N. H. Search for Related Content PubMed Articles by Mandal, U. K. Articles by Rao, N. H. Agricola Articles by Mandal, U. K. Articles by Rao, N. H. Related Collections Agroclimatology Water Management Evapotranspiration Dryland Cropping Systems Soil Hydrology Agricultural Systems Soil Models Irrigation

SOIL WATER DYNAMICS

Profile Water Balance Model under Irrigated and Rainfed Systems

^a Div. of Resour. Manage., Cent. Res. Inst. for Dryland Agric., Santoshnagar, P.O.-Saidabad, Hyderabad-500059, India
^b Div. of Agric. Physics, Indian Agric. Res. Inst., Pusa, New Delhi-110012, India
^c Natl. Acad. of Agric. Res. and Manage., Rajendranagar, Hyderabad-500030, India

* Corresponding author (uttamkm{at}crida.ap.nic.in)

Received for publication November 20, 2000. A profile moisture model has been developed to evaluate the seasonal soil moisture fluctuation with respect to soil characteristics and land use pattern under irrigated and rainfed conditions in an area of agricultural fields. Daily rainfall and irrigation were used as model inputs. Instantaneous uniform redistribution of soil moisture in the effective root zone and negligible contribution of soil water through upward flux were assumed. An empirical model was used to determine the root depth. Runoff was estimated from rainfall data using the curve number technique of the Soil Conservation Service adapted for conditions in India and combined with a soil moisture–accounting procedure. The modified Penman method was used to calculate the reference evapotranspiration. To calculate the crop coefficient (Kc), regression equations were developed taking Kc as the dependent variable on normalized difference vegetation index. This model was very easy to parameterize and required a minimum soil data set of field capacity and permanent wilting point. To evaluate model performance, observed values of soil water were taken for wheat (Triticum aestivum L.) in the Mehrauli (sandy loam to loam texture) and Daryapur (loamy texture) soil series under irrigated conditions and for gram (Cicer arietinum L.) in the Jagat (clay loam texture) and Holambi (loam texture) soil series under rainfed conditions in Delhi. The r² and D index between observed and predicted soil water values varied between 0.67 and 0.77 and 0.83 and 0.93, respectively.

Abbreviations: AMC, antecedent moisture conditions • CN, curve number • DAS, days after sowing • ET, evapotranspiration • FC, field capacity • NDVI, normalized difference vegetation index • PET, potential evapotranspiration • PWP, permanent wilting point