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.

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.

Recent changes to sugarcane management practices may have the potential to increase soil organic carbon and help reduce greenhouse gas emissions.  We examined changes to soil organic carbon in response to trash retention and no-till management at 4 sites throughout Queensland, but observed no increase in organic carbon stocks over the top 0.1 m or 0.3 m of the soil profile.  The use of such practices is thus unlikely to lead to significant carbon sequestration for the purposes of greenhouse gas abatement.

Quantifying the different effects of environmental parameters, land-use history, and management practices on soil organic carbon nitrogen, and bulk density is required to better inform management of agricultural soils. Cropping sites had one third less carbon than pasture sites and clay-rich soils contained the greatest carbon stocks. Farmers can influence SOC more by their choice of land use than their day-to-day soil management but they are able to select practices for their ability to retain more SOC.

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.

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.

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.

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.    

Changes to crop management practices may have the potential to increase soil carbon storage and decrease the emission of greenhouse gasses. This study found that management practices such as no-till, stubble retention and nitrogen fertiliser addition were not capable of increasing soil carbon stocks under the climatic conditions found throughout Queensland, Australia. To increase soil carbon stocks in this region a period of carbon input in the form of a pasture ley is likely to be required.