Using TDR and modeling tools to investigate effects of interactive factors on preferential flow and transport in field sandy clay soil

Merdun H.

ENVIRONMENTAL EARTH SCIENCES, cilt.71, sa.4, ss.1821-1838, 2014 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 71 Sayı: 4
  • Basım Tarihi: 2014
  • Doi Numarası: 10.1007/s12665-013-2586-6
  • Dergi Adı: ENVIRONMENTAL EARTH SCIENCES
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.1821-1838
  • Anahtar Kelimeler: Groundwater contamination, Soil properties, Application rate, HYDRUS-1D, MACRO, TIME-DOMAIN REFLECTOMETRY, WELL-STRUCTURED SOIL, DUAL-POROSITY MODEL, SOLUTE TRANSPORT, WATER-CONTENT, UNDISTURBED SOIL, MACROPORE FLOW, POROUS-MEDIA, ELECTRICAL-CONDUCTIVITY, VADOSE ZONE
  • Akdeniz Üniversitesi Adresli: Evet

Özet

Investigation of the extent of preferential flow
and transport affected by several factors and their interac-tions in the vadose zone using the advanced measurement
and modeling techniques is crucial for protection of
groundwater from agricultural chemicals like fertilizers
and pesticides. The objectives of this study were to
investigate the interactive effects of factors like soil
structure, initial soil water content (SWC), and application
rate on preferential flow and transport using the time
domain reflectometry (TDR) measurements of SWC and
electrical conductivity (EC) in the plots of 12 treatments in
a sandy clay field soil, applying the models (HYDRUS-1D
and MACRO) to the measured data, performing Tukey test
statistical analysis, and relating model parameters to basic
soil properties, consequently, flow and transport charac-teristics. Analysis of response times and the changes in
SWC and EC with time during the experiments in the
profiles of the treatments confirmed the existence of pref-erential flow and transport at the site. As long as the other
factors or conditions were constant; undisturbed versus
disturbed soil, wet versus dry initial SWC, and high versus
low application rate caused preferential flow and transport
in the soil based on the TDR measurements. Overall
HYDRUS-1D had better performance than MACRO in the
simulations of the measured data. These results suggest that
different scales of these factors in different field soils need
to be further studied for better understanding the flow and
transport processes in the vadose zone.