95 research outputs found
The SARP-project phase 3 (1992 - 1995) : overview, goals, plans : proceedings of the SARP research planning workshop held at the International Rice Research Institute, Los Banos, Philippines, 19 - 21 March, 1992
Nitrogen economy of irrigated rice : field and simulation studies : proceedings of the 'International workshop on nitrogen management and modelling in irrigated rice', held at the Crop Experiment Station, Rural Development Administration, Suweon, Korea, 1 - 10 November 1993
Preserving soil quality under irrigation in the Senegal River Valley
Soil quality under irrigation in the Senegal River Valley may become affected by salinization (Delta) and alkalinization (Middle Valley) processes. The salinity status of 158 irrigated rice fields in the Delta was measured with an electromagnetic conductivity meter. Double-cropped fields (two rice crops per year on the same field) were least saline (average horizontal reading: 0.6 dS/m), followed by single-cropped drained fields (1.6 dS/m), single-cropped non-drained fields (2.5 dS/m), non-cropped sites outside irrigation schemes (4.7 dS/m) and abandoned fields (5.7 dS/m). Results illustrated that when cultivating rice in the delta, the ponded water on the soil surface blocks capillary rise of salt from the water table. In the valley, the difference in the total amount of carbonates in 1:50 soil extracts between cultivated and non-cultivated sites was used as an indicator for alkalinization risk in 27 irrigation schemes. Highest rates of carbonate accumulation (0.65 meq HCO3-/(kg soil) per cropping season) and, therefore, greatest soil degradation risk were observed in schemes without drainage, compared to 0.10 meq HCO3-/(kg soil) per cropping season in schemes with good irrigation and drainage facilities. Plot and scheme level recommendations that may preserve soil quality under irrigation are presented
Water use efficiency of flooded rice fields. I. Validation of the soil-water balance model SAWAH.
The use of crop growth models in agro-ecological zonation of rice.
This volume of the SARP Research Proceedings presents a framework for the use of crop growth models in agro-ecological characterization and zonation of ric
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