INTERNATIONAL RICE RESEARCH INSTITUTE (IRRI)
Physico-chemical properties of submerged soils in relation to fertility
THE ABILITY OF SOIL TO SUPPLY NUTRIENTS DEPENDS ON THE PRESENCE IN THE SOIL OF ADEQUATE NUTRIENTS IN FORMS THAT PLANTS CAN ABSORB, THE SOIL"S ABILITY TO DELIVER NUTRIENTS BY MASS FLOW AND DIFFUSION TO THE ROOT SURFACE, THE PRESENCE OF A FAVORABLE IONIC COMPOSITION, AND THE ABSENCE OF SUBSTANCES WHICH INTERFERE WITH MOVEMENT OF NUTRIENTS INTO THE ROOT.
Ponnamperuma, F. N. · 1970
Sign in to readA free account is required to download.
Abstract
THESE FACTORS ARE INFLUENCED BY THE PHYSIOCOCHEMICAL PROPERTIES OF THE SOILS. A PH OF ABOUT 6.6, AN EH OF ABOUT 2 MMHO/CM AT 25 DEGREES C, AND A TEMPERATURE FROM 30 TO 35 DEGREES C APPEAR TO FAVOR NUTRIENT UPTAKE BY RICE. UNDER THESE CONDITIONS THE AVAILABILITY OF NITROGEN, PHOSPHORUS, POTASSIUM, CALCIUM, MAGNESIUM, IRON, MANGANESE, AND SILICON IS HIGH, THE SUPPLY OF COPPER, ZINC, AND MOLYBDENUM IS ADEQUATE, AND INJURIOUS CONCENTRATIONS OF ALUMINUM, MANGANESE, IRON, CARBON DIOXIDE AND ORGANIC ACIDS ARE ABSENT. IN NORMAL TROPICAL SOILS THESE CONDITIONS CAN BE ACHIEVED BY INCORPORATING ORGANIC MATTER AND KEEPING THE SOIL SUBMERGED FOR 2 TO 4 WEEKS BEFORE PLANTING. THIS REPORT INCLUDES MANY GRAPHS AND TABLES, AND AN EXTENSIVE BIBLIOGRAPHY.
Connected topics
Related documents
