| Autor: |
G. F. Barkle, Terry N. Brown, D. J. Painter |
| Rok vydání: |
1999 |
| Předmět: |
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| Zdroj: |
Soil Science. 164:252-263 |
| ISSN: |
0038-075X |
| DOI: |
10.1097/00010694-199904000-00005 |
| Popis: |
In New Zealand, regulatory authorities have selected controlled application of dairy farm effluent onto pasture as the best practical treatment option. Nitrogen leaching studies have found undissolved or particulate (>0.2 μm in size) as well as dissolved organic material in drainage waters as a result of the application of this effluent onto poorly drained soils. This paper describes a detailed investigation into the leaching behavior of the particulate fraction of dairy farm effluent applied onto a poorly drained soil. The study entailed dividing the particulate fraction of dairy farm effluent into a number of arbitrary size-classes and determining the amounts of organic carbon present in each of these classes by physical filtration and carbon measurement. This effluent was then applied to a number of undisturbed soil cores from soil horizons of a poorly drained soil. The filtration characteristics of the soil horizons were determined by differences between the carbon in the applied effluent and the leachate for each size-class. Results show that when the upper horizons of the soil are at water contents greater than field capacity, between 27 and 34% of the carbon applied in dairy farm effluent can be leached through the top horizons. As expected, most of the material that was filtered out came from the larger size-classes; 84% of the carbon applied was greater than 2.7 μm in size, and more than 83% of this was retained in the top soil horizons. In the smaller size-classes ( |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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