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A Kjeldahl digestion method normally used for total nitrogen (N) was compared with NaOH fusion and dry ashing methods for determination of total phosphorus (P). Overall there was good correlation between the methods (r2=0.996). Results from the digestion method were on average 3.7% lower than the fusion and dry ashing methods, but there were significant differences between methods as shown by the regression analysis. The digestion method proved suitable for analysis of highly organic soils and some soils from the Pacific Islands. It was also useful for estimation of total ? in well‐weathered soils such as Oxisols and in A horizons, but not suitable for less weathered mineral soils.

The organic carbon in New Zealand's vegetation and soils has been estimated for 1992 from updated national databases of vegetative cover and soil carbon. These databases were augmented by inclusion of vegetation and soils information for Stewart Island, and addition of carbon estimates for upland and high‐country soils of South Island. Plant biomass estimates from literature were combined with the Vegetative Cover Map of New Zealand to give an estimate of 2420 Mt carbon for vegetation carbon above and below ground, including litter and humus. More than 80% of this carbon occurs in indigenous forested ecosystems on less than 26% of the land area, with only about 5% in planted forests. Soil organic carbon estimates for two depth ranges (0–0.25 m, 0–1 m) were derived from the N.Z. Land Resource Inventory, the Soil Map of Stewart Island, and the National Soils Database. Totals were 2500 ± 77 Mt and 4260 ± 190 Mt C respectively. Yellow‐brown earths made the largest contribution, with 727 Mt C in North Island a...

Levels of cadmium (Cd) in New Zealand pastoral soils have increased due to Cd impurities in applied fertilisers. As there is little information on the interaction of Cd with soil mineral‐organic matter complexes, the sorption of Cd by complexes of kaolinite with humic acid has been investigated. Sorption was measured at pH and ionic strength values typically found for solutions of pastoral soils in New Zealand. Sorption increased with the content of humic acid in the complex, and as the pH of the medium was raised from 4.2 to 6.3. Sorption was also influenced by the ionic strength of the ambient solution, notably by the nature of the cation in the added electrolyte. The experimental data were interpreted in terms of the effect of solution pH and ionic composition on the charge characteristics of kaolinite and humic acid. These factors, in turn, influence clay particle association as well as the clay‐humic and metal‐humic interaction.

A synthesis of 6-amino-7-cyclohexyl-3,5-heptanediol 1 (CDH) and related amino 1,3-diols involving a nucleophilic ring opening of N-acyl activated lactams is described. Stereochemical proof of the 1,3-diol moiety is also presented.

The single crystal x-ray structure of NECA (1-(6-amino-9H-pu-rin-9-yl)-1-deoxy-N-ethyl-β-D-ribofuranuronamide), a 5′-modified adenosine analogue, is reported. Crystallized from methanol as the monohydrate, NECA exists in a syn conformation (sugar syn to purine) in the solid state, consistent with both solution measurements and theoretical calculations. The biological profile of NECA may result from this conformational preference.