Chemistry of rainfall, throughfall and stemflow in a eucalypt forest and a pine plantation in south-eastern Australia: 1. Rainfall

✍ Scribed by R. H. Crockford; D. P. Richardson; R. Sageman

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 801 KB
• Volume: 10
• Category: Article
• ISSN: 0885-6087
• DOI: 10.1002/(sici)1099-1085(199601)10:1<1::aid-hyp295>3.0.co;2-v

✦ Synopsis

Rainfall samples were collected from several hundred rainfall events. Up to nine samples per event were collected TI-om sites 3-500 m apart. They differed substantially in both concentration and composition, even though great cLire w a s taken to wash all collectors beforehand. Dryfall, storage and analytical procedures could not explain the variation.

When data for rainfall events of similar size (but very different cation inputs) were examined, the major diffei-ewes were associated with the prevailing wind direction. Events leading to high concentrations were associated with easterly winds and showed the influence of a marine source.

Chemical concentration and composition were not altered by the occurrence of a drought year followed by a very wet year. The mean pH was 5.3 and ranged from 4.6 to 5.8. For a given event, a difference of 0.5 often occurred between collection sites. Regular seasonal variations in the concentration of N03-N and the NO3/NH4 ratio occurred. with the ratio being higher in summer due primarily to bush fires. Organic nitrogen comprised 14% of total nitrogen.