International communication of soil knowledge is reliant upon soil classifications that encompass all known soils, but Australia has been reluctant to use such soil classifications due to their perceived unsuitability to Australian conditions. This study applied international soil classifications to soils on the NSW north coast, finding that some important soil groups were not discriminated. The study will contribute to the consideration of Australian soils in future revisions of international soil classifications, ensuring better, more informed communication between soil scientists.    

The vertical variability of soil texture influences water movement and solute transfer. Our study investigated the soil-profile textures in an arid region of north-western China, and found that the transitions between adjoined textural layers in soil profiles can be quantitatively described by a Markov chain-log-normal distribution model. This research will serve for the insight into the relationship between soil textures and hydraulic properties in soil profiles in the study area.

Although the susceptibility of tropical soils to compaction has been discussed in various scientific articles, the knowledge of soils with various textures is scarce. In this paper, informations of Brazilian Soils used to support decision toward more sustainable use and management of agricultural land were determined and we verified more susceptibility to soil compaction with the increasing clay content, being practically inevitable some additional compaction in clayey and very clayey soils. Our results increase the understanding on the highly weathered Brazilian soils behaviour.

In Australia, the acidity harzard in Acid Sulfate Soils (ASS) is routinely assessed using two techniques called Net Acid Soluble Sulfur (S_NAS) and Residual Acid Soluble Sulfur (S_RAS). The present study evaluated these two techniques and discovered that both techniques were unable to provide a reliable estimation of poorly soluble iron hydroxy sulfate minerals such as schwertmannite and jarosite. Thus, the management practices derived from the assessments of these two techniques would require careful consideration before their application in ASS.

Most studies of nutrient cycling in strongly weathered tropical soils assume that phosphorus is physically protected, or occluded, and thus it is not readily available to plants for growth. This paper examined changes in amounts of phosphorus in several different places in soils, seasonally and in response to phosphorus fertilisation, and showed that some of the physically bound forms can be quite active and changing. The results highlight the importance of poorly studied occluded forms of phosphorus in maintaining productivity of lowland tropical forests.

Surface charge of soil particles can influence some processes, such as adsorption-desorption of nutrients in the soils. The effects of Fe oxides and organic matter interaction on surface charge of tropical red soils have not been well explained. Results of this study indicated that negatively charged sites of red soils could partly be blocked by organic matter or metal-organic matter complexes, and these soils can have net negative charges at natural soil pH which are useful for fertilizer management planning.

Leaching of nutrients from compost can reduce the benefits of compost to soils and plants. We tested if mixing of fine-texted soil with the compost (0–20% w/w) can reduce leaching in a sandy soil. Mixing of fine-texted soil reduced leaching of N and P from compost and thereby the risk of eutrophication.

The discovery of ammonia oxidising archaea (AOA) in 2004 changed our understanding of the microbiology of the nitrogen cycle. Until then, the conversion of ammonia to nitrite was thought to be carried out only by ammonia oxidising bacteria (AOB). This work shows that both AOB and AOA are widespread in soils in South Australia and Western Australia. Both microbial groups contribute to nitrification rates and, if soil fertility is high, then nitrification rates will be high regardless of whether AOA or AOB dominate. A greater understanding of the soil microbial community will increase our ability to manage nitrogen in agricultural systems.