Soil physical measurements are essential for solving many natural resource management problems. This operational laboratory and field handbook provides, for the first time, a standard set of methods that are cost-effective and well suited to land resource survey. It provides: practical guidelines on the soil physical measurements across a range of soils, climates and land uses; straightforward descriptions for each method (including common pitfalls) that can be applied by people with a rudimentary knowledge of soil physics, and guidelines on the interpretation of results and integration with land resource assessment. Soil Physical Measurement And Interpretation for Land Evaluation begins with an introduction to land evaluation and then outlines procedures for field sampling. Twenty detailed chapters cover pore space relations, water retention, hydraulic conductivity, water table depth, dispersion, aggregation, particle size, shrinkage, Atterburg limits and strength. The book includes procedures for estimating soil physical properties from more readily available data and shows how soil physical data can be integrated into land planning and management decisions.

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The water-vapor permeability (WVP) and mechanical properties of edible films formed from dry blends or co-dried preparations of protein-polysaccharide powders prepared from whey protein concentrate ( WPC)-45 and alginate, pectin, carrageenan, or konjac flour ( WPC-45-to-polysaccharide ratio of 95:5 w/w) were investigated. Films were prepared from 8% WPC using WPC-45 (45% protein powder), consisting of 17.76 g of WPC-45 in 82.84 g of water per 100 g solution to give 8% protein w/w. Films formed from co-dried powders had lower WVP and higher tensile strength (TS), elastic modulus (EM) (P < 0.05), and elongation (EL) than equivalent films formed from the dry blended powders. Films containing alginate had lower WVP and higher TS, EM, and EL than films containing pectin, carrageenan, or konjac flour. There is potential to alter the physical properties of hydrophilic films by combining whey protein and polysaccharide components.

In recent years, a number of physically based models have been developed for soil loss predictions. GUEST is one such model based on fundamental physical principles and the current understanding of water erosion processes. GUEST is mainly used to determine a soil erodibility parameter. To apply the model in a predictive mode, the model is simplified in a physically meaningful manner for flow-driven erosion processes, and 2 essential hydrologic variables are identified, namely total runoff amount and an effective runoff rate. These variables are required to determine soil loss for individual runoff events. A simple water balance model was developed and used to predict runoff amount from rainfall amount. The efficiency of this runoff amount model in prediction was over 90% using field data. A 1-parameter regression model (r2 ~ 0·9) for the effective runoff rate was also established which uses peak rainfall intensity in addition to rainfall and runoff amounts. The prediction of peak rainfall intensity for a given rainfall amount and storm type was also sought. The field data were from Goomboorian, near Gympie, in south-east Queensland and these data were used to test and validate both models. Results overall are satisfactory and the approach adopted is promising. A framework for soil loss prediction is established within which individual parts can be further refined and improved.

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