CIGR2010-book-abstra..

ESTIMATING RECLAMATION WATER REQUIREMENT AND PREDICTING FINAL
SOIL SALINITY FOR SOIL DESALINIZATION
A. SARRAF 1 , F. VAHDAT 2 , E. PAZIRA 2 , H. SEDGHI 2
1
A. SARRAF, Faculty Staff of Agriculture, Islamic Azad University, Roudehen Branch, Roudehen, Iran, pooya.amir@yahoo.com. 2 F. VAHDAT,
Ph.D. Student in Water Resources engineering, Faculty of Agriculture and Natural Resources, Science and Research Branch, Islamic Azad
University ,Tehran-Iran, farnood_v@yahoo.com. 2 E. PAZIRA, Faculty Staffs of Agriculture and Natural Resources, ebrahimpazira@yahoo.com., 2
H. SEDGHI, Faculty Staffs of Agriculture and Natural Resources, Hsedghi@yahoo.com.
CSBE100133 – The study area was located at central part of Khuzestan province, Iran. Soil survey
and land classification of the area showed that from total surveyed area of about 41,855 hectares,
an area of about 14,100 hectares (33.7%) were Saline/Saline –Sodic soils, in different extents. Also
about 36,430 hectares (87.0 % of the total area) was subjected to water logging and poor internal
drainage conditions. To study the possibilities of Desalinization and Desodification, six different
sites were selected in the most Saline – Sodic parts of the study area for which eight treatments
(six for leaching water applications and two with gypsum as soil amendment) by means of 1.0
meter depth of leaching water application in four 0.25 meter intervals. Soil samples were taken
before, during and after each leaching water application interval. The collected soil and water
samples were then analyzed in the laboratory. Based on the collected data from salt leaching
experiments, the Desalinization and Desodification leaching curves were obtained. Different
theoretical models were also tested by comparing the calculated and experimental Desalinization
and Desodification data. Reasonable agreements between theoretical and typical experimental
leaching curves were observed. Some empirical exponential relationships were then obtained,
enabling users to insert leaching efficiency coefficient and volumetric soil water content and depths
to predict both final soil salinity and sodicity […].
POTENTIAL WATERSHED NITRATE LOAD REDUCTION WITH DRAINAGE WATER
MANAGEMENT UNDER VARIED IMPLEMENTATION OPTIONS
S. ALE 1 , L. BOWLING 1 , M. YOUSSEF 2 , S. BROUDER 1 , J. FRANKENBERGER 1
1 S. ALE, Postdoctoral Research Associate, Dept. of Agronomy, Purdue University, West Lafayette, IN-47907, United States, srinu@purdue.edu. 1
L. BOWLING, Assistant Professor, bowling@purdue.edu., 1 S. BROUDER, Professor, sbrouder@purdue.edu., 1 J. FRANKENBERGER, Professor,
Dept. of Ag. and Biol. Engineering, frankenb@purdue.edu., 2 M. YOUSSEF, Assistant Professor, Dept. of Biol. and Ag. Engineering, NC State
University, Raleigh, NC- 27695, United States, mohamed_youssef@ncsu.edu.
CSBE100137 – The potential impact of drainage water management (DWM) on the nitrate load
from subsurface drainage in the Hoagland watershed in west central Indiana was assessed using the
DRAINMOD 6.0 model. The watershed was divided into 6460 grid cells of 180 x 180 m size and
the drain spacing, soil parent material and cropping pattern in each of the grid cells were identified
from the analysis of high resolution aerial photographs and from the GIS-based analysis of soil,
crop land and land cover datasets. The DRAINMOD model was applied to each cell and the nitrate
loss through subsurface drains was estimated for the conventional and DWM cases. The delivery
ratio (DR), which is the fraction of the nitrate load delivered from the field edge to the watershed
outlet, was estimated for each of the grid cells using measured nitrate attenuation rates and
calculated travel times. A 44% reduction from the current average (1987-2006) annual nitrate load
of 155 metric tons was predicted with the implementation of DWM in all subsurface drained fields
in the watershed. The effects of multiple management scenarios of DWM implementation based on
drain spacing, soil parent material, DR and distance from the ditches/streams were evaluated with
respect to the percent reduction in annual nitrate load at the watershed outlet. The highest percent
reduction in average annual nitrate load, on a per unit area basis, was predicted from
implementation of DWM in the grid cells formed from the Eolian sand parent […].
44
XVII th World Congress of the International Commission of Agricultural and Biosystems Engineering (CIGR) – Québec City, Canada – June 13-17, 2010