Soil Chemical Methods – Australasia describes over 200 laboratory and field chemical tests relevant to Australasia and beyond. The information and methodology provided across 20 chapters is comprehensive, systematic, uniquely coded, up-to-date and designed to promote chemical measurement quality. There is guidance on the choice and application of analytical methods from soil sampling through to the reporting of results. In many cases, optional analytical ‘finishes’ are provided, such as flow-injection analysis, electro-chemistry, multiple flame technologies, and alternatives to chemical testing offered by near-range and mid-range infrared diffuse reflectance spectroscopy. The book supersedes and updates the soil chemical testing section of the 1992 Australian Laboratory Handbook of Soil and Water Chemical Methods of Rayment and Higginson, while retaining method codes and other strengths of that Handbook. Chapters cover soil sampling, sample preparation and moisture content; electrical conductivity and redox potential; soil pH; chloride; carbon; nitrogen; phosphorus; sulphur; gypsum; micronutrients; extractable iron, aluminium and silicon; saturation extracts; ion-exchange properties; lime requirements; total miscellaneous elements; miscellaneous extractable elements; alkaline earth carbonates and acid sulfate soils. In addition, there are informative Appendices, including information on the accuracy and precision of selected methods. This book targets practising analysts, laboratory managers, students, academics, researchers, consultants and advisors involved in the analysis, use and management of soils for fertility assessments, land use surveys, environmental studies and for natural resource management.

Cadmium (Cd) has been identified as a potential contaminant in foods posing health risks to humans and, in Australia, potatoes (Solanum tuberosum L.) have been identified as contributing a large proportion of the average dietary Cd intake. To assess the concentrations of Cd in Australian potatoes and soil factors likely to lead to high Cd concentrations, commercial crops and soils were sampled at 352 sites throughout potato production areas in Australia. Across all states, fresh weight (FW) tuber Cd concentrations ranged from 0.004 to 0.232 mg kg−1 with an overall mean value of 0.041 and a median of 0.033 mg kg−1 (FW). Approximately 92 samples out of 359 (25.6%) exceeded the current maximum permitted concentration (MPC) of 0.05 mg kg−1 (FW) and 18 (5.0%) exceeded 0.1 mg kg−1 (FW). Concentrations of Cd (EDTA‐extractable) in topsoils ranged from 0.01 to 0.59 mg kg−1 with mean and median values of 0.14 and 0.10 mg kg−1, respectively. There was no relationship between Cd concentrations in soil and tubers. Stepwise forward multiple regression analysis of the data indicated that Cl and Zn concentrations in the topsoil, soil pH, and potato cultivar accounted for 57% of the variation in tuber Cd concentrations, with Cl being the dominant factor. Comparison of soil‐plant transfer coefficients (TCs) for Cd with limited international data sets suggests that TCs for Australian soils used for potato production are relatively high.

Vegetables were collected near peak harvest from the main production regions in Queensland and were analysed for residues of nitrate and nitrite. A small sample of hydroponic produce was also included in the survey. Nitrite-N from 1 to 4 mg kg-' was found only in dwarf beans and in lettuces. Levels of nitrate in potatoes, cabbages and beets were higher than those reported in other surveys and exceeded threshold limits set in one other country. The median nitrate-N concentration measured in hydroponic lettuce (465 mg kg-nitrate-N) was more than twice the median concentration for field-grown lettuce. Poor correlation between total N and nitrate in vegetables raises doubts about the use of total N alone as an indicator of N status.

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Water quality condition and trend are important indicators of the impact of land use on the environment, as degraded water quality causes unwelcome changes to ecosystem composition and health. These concerns extend to the sea, where discharges of nutrients, sediments and toxicants above natural levels are unwelcome, particularly when they drain to the Great Barrier Reef World Heritage Area and other coastal waters of Queensland. Sugarcane is grown in 26 major river catchments in Queensland, most in environmentally sensitive areas. This puts pressure on the Queensland Sugar Industry to manage the land in ways that have minimum adverse off-site impacts. Sugar researchers including CRC Sugar have been associated with water quality studies in North Queensland. These include investigations and reviews to assess the role of groundwater as a pathway for nitrate loss from canelands in the Herbert Catchment, to find causes of oxygen depletion in water (including irrigation runoff) from Ingham to Mackay, to use residues of superseded pesticides as indicators of sediment loss to the sea, and to assemble information on water quality pressure and status in sugar catchments. Key findings, plus information on input pressures are described in this paper, and areas of concern and opportunities discussed.