No abstract

Lyday performed all modifications to the PF-COMP computer program, made the initial production runs of the program, and was assisted by Mr. Bu L W. Howard in the formulation and progranmning of the analytical routine for improving shelters in basement areas on a cost/effectiveness basis; Mr. Philip S. McIullan reviewed the background for OCD use of PF 40 as the minimum acceptable for fallout shelter space; Mr. Milton D. Wright progranmmed the shelter boundary procedure routine and made the hand computations required for the program test problem. liii BIBLIOGRAPHY

Using geographic information system techniques, hydrology of soil types (HOST) classes were combined with slope, rockiness, flood hazard and soil moisture deficit classes within a risk matrix to produce a slurry acceptance map for Northern Ireland (NI) on a 50 m grid. Moreover, due to the whole territory of NI being designated as a nitrate vulnerable zone, a nitrates action programme is to be implemented across the region in the near future and this is likely to restrict slurry applications to the growing season. To assess the risk classes associated with slurry applications during the growing season, an additional slurry acceptance map for NI was created in which the HOST factor was excluded from the analysis. The maps created showed that, for the period January–December, the majority (80%) of agricultural soils in NI were in the severe risk category following application of 50 m3 ha−1 of slurry. However, this proportion was reduced to only 29% when the same volume of slurry was applied during the growing season, when the soils were not saturated and significant rainfall was not received in the period immediately after slurry application.

SUMMARYThe soils of on area around Llangadog (mid-Wales) have been systematically sampled on a grid basis at 0–8 cm and 30–35 cm depths.A P-sorption index was determined for these samples as were Fe and Al extractable by both 0·1 M K-pyrophosphate solution and 0·2 M-NH4-oxalate solution at pH 3. The reactivities of the soils with 1 M-NaF solution at pH 6·8 and pH 8 were also measured.The results were stratified in terms of parent material, soil classification at subgroup level and soil series, and correlation coefficients calculated between the P-sorption index and the other variables (singly and in combination).Only pyrophosphate-extractable Fe, i.e. ‘organically bound’, correlated reasonably well with the P-sorption index. However, the correlation was such that tolerably good estimates of P-sorption in an agronomic context could be made from pyrophosphate-extractable Fe values only for previously uncultivated brown podzolic soils (Manod series).Fluoride reactivities at both pH values were poor predictors of P-sorption in these soils. Fluoride reactivity at pH 6·8 and oxalate-extractable Al, which have both been proposed as indices of the amounts of ‘poorly-ordered’ Al compounds in soils, failed to group these soils in similar ways. Doubt exists therefore as to whether these variables are measures of the same (or similar) property in these soils.