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The search for the mediaeval philosopher’s stone and the search for effective phosphate solubilizing microorganisms are analogous. Both are based on an erroneous assumption about nature. Advocates for phosphate solubilizing microorganisms think that P is present in soils as discrete compounds of iron, aluminium, and calcium. This is not consistent with many observations. Rather, P is adsorbed on, and penetrates, into variable-...
Deliberately introduced dung beetles in A ustralia: 12 years of occurrence and abundance records from 2001 to 2022NARA Subscribed
Since 1968, the Australian Dung Beetle Project has carried out field releases of 43 deliberately introduced dung beetle species for the biological control of livestock dung and dung‐breeding pests. Of these, 23 species are known to have become established. For most of these species, sufficient time has elapsed for population expansion to fill the extent of their potential geographic range through both natural and human‐assiste...
Chickpea ( Cicer arietinum ) is known to secrete organic anions. We investigated its effectiveness in obtaining P over a range of pH values. Methods We grew two cultivars of chickpea, supplied with either ammonium or nitrate nitrogen, at 10 levels of applied P, and at four initial pH values. We measured plant weight, P concentration in the tops, and rhizosphere pH. We compared the results with those previously obtained for luc...
Investigating the dissolution of soil phosphateNARA Subscribed
Aims The effectiveness of phosphate fertilisers decreases with increasing period of reaction. One explanation for this is that the phosphate (P) has changed its chemical form. Evidence for this is provided by fractionation schemes which include extraction with alkali, followed by extraction with acid. Our aim was to test whether alkali and acid extracted different moieties and to test their ability to reflect changes in phosph...
The effects of pH on nutrient availability are not solely caused by to the effects on reaction with soils but are an interaction between these effects and the effects on rate of uptake by plants. Some effects are specific to particular ions, but an important aspect is that plant roots and soil particles both have variable charge surfaces. This influences availability, but in opposite directions. Sulfate is an example of this i...
Evaluating the benefits of legacy phosphateNARA Subscribed
Aims Many soils in the developed world have been fertilized with phosphate for several decades. Appreciable phosphate has accumulated in such soils. This is referred to as “legacy P”. The benefits of legacy P are not widely appreciated. Here, we report the effects of legacy P on buffering capacity and the consequent effects on the effectiveness of plant growth, and its effects on the continuing reaction between soil and P and...
How understanding soil chemistry can lead to better phosphate fertilizer practice: a 68 year journey (so far)NARA Subscribed
This paper describes a journey which started with the question: why do farmers reapply phosphate? This led to understanding how phosphate and other specifically sorbed ions, both cations and anions react with soil. Under most soil conditions, they do not precipitate to give specific compounds. Rather they are specifically adsorbed onto the surface of soil particles and then penetrate the particles via diffusion mechanisms. The...
The soil phosphate fractionation fallacyNARA Subscribed
Evaluating hypotheses of expansion from refugia through comparative phylogeography of south‐eastern Coastal Plain amphibiansNARA Subscribed
Aim Early genetic studies in the south‐eastern United States provided the foundation for ideas in the field of comparative phylogeography, but few direct comparisons with consistent sampling across taxa exist for this region. We investigate the influence of historical processes and species‐level characteristics on phylogeographic structure within four anuran species, evaluate previously described biogeographic patterns, and te...