Effects of Liming on Yields and Composition of Heavily Fertilized Grasses and on Soil Properties Under Humid Tropical Conditions

Abstract

Heavily fertilized tropical grasses responded strongly to liming on two typical soils of the Humid Tropics. Liming increased the Ca and decreased the Mn content but did not affect the phosphorus or Mg content of the grasses. Surface applications of limestone were as effective as mixing limestone with the surface soil and one application was as effective as two applications at 2‐year intervals. Exchangeable Al and Mn content of the soils was sharply increased by fertilization alone but was decreased by liming. Base content at all depths sampled was decreased by fertilization alone but was increased by surface liming followed by heavy fertilization. Yields of grasses increased markedly with pH of the upper 6 inches to about 4.8, with bases to 8.0 me. per 100 g. of soil and with decreasing exchangeable Al to 2 me. per 100 g. of soil. Heavy fertilization of grasses over a 4‐year period without liming greatly depressed yields of subsequently planted tobacco and this effect was only partly compensated by reliming prior to planting the tobacco.

A Critical Review on Soil Chemical Processes that Control How Soil pH Affects Phosphorus Availability to Plants

“…As an alternative comparison, the same solutions were titrated with NaOH to maintain pH 4. First, addition of the salts displaced Al 3+ and allowed for Al phosphate precipitation as expected, but the precipitation reaction caused pH to further decrease because protons are a product of this reaction (Reaction (9)). This inhibited further Al phosphate precipitation.…”

“…Much of the research on basic soil P chemistry was conducted from the 1950s to the 1970s; even at that time there were some contradictory reports. Amarasiri and Olsen [3] commented that "the experimental evidence on the effect of lime on P availability to plants is inconclusive", citing studies that showed that lime increased [4,5], decreased [6,7], or did not change [8,9] plant P concentration. Similarly, in a review that included P by lime interactions, Sumner and Farina [10] showed that there were many inconsistencies in the literature regarding the impact of pH on P uptake.…”

“…Essentially, decreased pH (i.e., increased H + ) will promote dissolution of Al and Fe oxides and hydroxides through hydrolysis of Al and Fe. The resulting solution Al 3+ and Fe 3+ can then directly precipitate with solution P; i.e., increased acidity promotes Reactions (4) and (5), which provide the chemical potential for Reactions (9) and (10) to proceed, thereby removing P from solution by precipitation. From the combination of Reactions (9)- (12), it should be apparent how the solubility of Al and Fe oxides and hydroxides can impact the formation and dissolution of Al and Fe phosphates; soils containing more soluble Al and Fe oxides and hydroxides (i.e., higher K values for Reactions (11) and (12)) will result in less soluble Al and Fe phosphates.…”

Long-Term Effects of Lime Additions on Sugarcane Yield and Soil Chemical Properties in North Queensland

“…The transfer of alkalinity to depth from surface applications or incorporations of lime has been reported previously by several authors (Abruna et al, 1964;Adams and Pearson, 1969). This is eected through the formation of Ca(NO 3 ) 2 in the limed topsoil in the presence of ammonium-based fertilizers and its subsequent leaching to the subsoil where the more rapid rate of assimilation of NO 3 7 over…”

Organic Matter Relationship to Soil Nutrient Status and Aluminum Toxicity in Alfalfa1

“…levels (Ragland and Coleman, 1959;Moschler et al, 1960;Shoop et al, 1961: Abruna et al, 1964. However, it is impossible to deduce from these reports a single common expression for the relationship between plant growth and exchangeable AP+.…”