| Autor: |
Giuffré, Lidia, Piccolo, Gabriel, Rosell, Ramón, Pascale, Carla, Heredia, Olga, Ciarlo, Esteban |
| Předmět: |
|
| Zdroj: |
Communications in Soil Science & Plant Analysis; 2001, Vol. 32 Issue 9/10, p1621, 8p |
| Abstrakt: |
Total organic phosphorus (P), labile organic P, and total carbon were determined in composite surface soil samples, with three replicates, in a Kandihumult from Misiones province, Argentina. The analysis was performed on <0.1 mm, 2-0.5 mm, and >8 mm aggregate fractions obtained by dry sieving. Representative situations were selected to evaluate changes in P dynamics by soil use: a native subtropical forest, a degraded agroecosystem with a 50-year yerba mate plantation (Ilex paraguariensis Saint Hill.), and a similar plantation with a 6-year associated elephant grass (Penniserum purpureum Schumach). Native pristine soil from the forest presented the highest content of phosphorus in more humified fractions (<0.1 mm). Fifty-year cultivation of "yerba mate" produced a degraded agroecosystem with 10% decrease of total organic phosphorus forms in humified fractions. Six-year-old elephant grass mulch incorporation increased total organic phosphorus both in more humified fractions and in macroaggregates (>8 mm), due to addition of decomposable organic materials. Labile organic phosphorus was higher under stress conditions. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
