A filter-paper technique that can be used to measure the matric potential of field soil is described in detail. When a calibrated batch of filter papers is used, the precision is limited by the variability between individual papers and the limitation of weighing to the nearest mg. The absolute accuracy is also limited by the instruments used for calibration. There was reasonable agreement between batches of the same type of paper, suggesting that our generalized calibration curves can be used for Whatman No. 42 filter papers where accuracy is not paramount.For potentials 2 -2.5 MPa, papers need to be equilibrated with the soil for 6 d. To achieve the same accuracy at lower potentials longer equilibration periods are required. Results suggest that the technique should be effective down to at least -100 MPa if soils are allowed to equilibrate fully with the papers. Coefficients of determination (r2) for the calibration lines were all 20.92. A regression of log( -matric potential) measured by the filter paper technique against measurements made using tensiometers and a psychrometer over a range of potentials between -1 kPa and -10 MPa gave an r2 value of 0.995.

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Small Island Developing States (SIDS) have high and increasing rates of diet-related diseases. This situation is associated with a loss of food sovereignty and an increasing reliance on nutritionally poor food imports. A policy goal, therefore, is to improve local diets through improved local production of nutritious foods. Our aim in this study was to develop methods and collect preliminary data on the relationships between where people source their food, their socio-demographic characteristics and dietary quality in Fiji and Saint Vincent and the Grenadines (SVG) in order to inform further work towards this policy goal. We developed a toolkit of methods to collect individual-level data, including measures of dietary intake, food sources, socio-demographic and health indicators. Individuals aged ≥15 years were eligible to participate. From purposively sampled urban and rural areas, we recruited 186 individuals from 95 households in Fiji, and 147 individuals from 86 households in SVG. Descriptive statistics and multiple linear regression were used to investigate associations. The mean dietary diversity score, out of 10, was 3.7 (SD1.4) in Fiji and 3.8 (SD1.5) in SVG. In both settings, purchasing was the most common way of sourcing food. However, 68% (Fiji) and 45% (SVG) of participants regularly (>weekly) consumed their own produce, and 5% (Fiji) and 33% (SVG) regularly consumed borrowed/exchanged/bartered food. In regression models, independent positive associations with dietary diversity (DD) were: borrowing/exchanging/bartering food (β = 0.73 (0.21, 1.25)); age (0.01 (0.00, 0.03)); and greater than primary education (0.44 (0.06, 0.82)). DD was negatively associated with small shop purchasing (−0.52 (95% CIs −0.91, −0.12)) and rural residence (−0.46 (−0.92, 0.00)). The findings highlight associations between dietary diversity and food sources and indicate avenues for further research to inform policy actions aimed at improving local food production and diet.

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