Potassium in soil and pasture and leaching of cations on an allophanic soil in New Zealand

Autor: C. G. Roach, M. J. Tong, A. H. C. Roberts, J. D. Morton
Rok vydání: 2004
Předmět:
Zdroj: New Zealand Journal of Agricultural Research. 47:147-154
ISSN: 1175-8775
0028-8233
DOI: 10.1080/00288233.2004.9513582
Popis: Potassium chloride (KCl) was applied at 0, 150, 450, and 750 kg ha−1 in May 2000 and April 2001 to an allophanic soil (Egmont brown loam) in South Taranaki to generate a range of soil and pasture potassium (K) levels typical of grazed dairy pastures. Initial mean soil quick test (QT) K levels of 7.0 increased to 7.3, 9.2, 13.6, and 18.5 respectively for each rate of K at the March 2001 sampling. In the March 2002 sampling, soil QT K decreased to 5.5, 7.8, 8.1, and 8.5 for each rate of K. There was only a small effect of rate of K on initial soil magnesium (Mg), calcium (Ca), and sodium (Na) soil QT levels of 30.8, 8.6, and 8.4. Pasture K content was significantly higher (P < 0.05) at the highest rate of K compared with control from July to December in Year 1 (July 2000‐May 2001) and January‐March in Year 2 (July 2001‐May 2002). Increasing rate of K did not significantly change pasture Mg and Ca in most months but significantly decreased pasture Na. Leachate collected at 1 m soil depth showed that...
Databáze: OpenAIRE
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