Plant Species and Defoliation Efects on Soil Nitrogen Mineralization in a Semiarid Rangeland of Argentina
The objective of this study was to evaluate the efects of moderate defoliation and grass species on soil nitrogen (N) mineralization in a semiarid grassland of northeastern Patagonia, Argentina. Studied species were Poa ligularis and Nassella tenuis (desirable/preferred by cattle) and Amelichloa amb...
| Authors: | ; ; ; ; ; ; |
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| Format: | Article |
| Status: | Published version |
| Publication date: | 2021 |
| Country: | Argentina |
| Institution: | CICBA |
| Repository: | CIC Digital (CICBA) |
| Language: | English |
| OAI Identifier: | oai:digital.cic.gba.gob.ar:11746/11335 |
| Online Access: | https://digital.cic.gba.gob.ar/handle/11746/11335 |
| Access Level: | Open access |
| Keyword: | Agronomía, reproducción y protección de plantas Poa ligularis Nassella tenuis Amelichloa ambigua Perennial grasses Inorganic soil N |
| Summary: | The objective of this study was to evaluate the efects of moderate defoliation and grass species on soil nitrogen (N) mineralization in a semiarid grassland of northeastern Patagonia, Argentina. Studied species were Poa ligularis and Nassella tenuis (desirable/preferred by cattle) and Amelichloa ambigua (undesirable/non preferred). Two defoliations were made to a 5 cm stubble height during the growing season. Hypotheses were that (1) net N mineralization and N availability in the soil are increased by a moderate defoliation and greater species forage quality, and (2) potential N mineralization is higher in the soil beneath the desirable than undesirable species. In 2013 and 2014, in situ net N mineralization was estimated using the tube incubation technique under feld conditions. Potential N mineralization was estimated by long-term laboratory incubations. Defoliation treatments did not afect the soil inorganic N dynamics. The soil under A. ambigua showed a greater in situ net N mineralization than other species, but only in 2013. Poa ligularis presented the highest initial inorganic N and potentially mineralizable N values. However, the opposite was recorded in this specie for the mineralization constant rate. These results demonstrated that moderate defoliations did not afect soil N availability, and presence of the desirable perennial grasses increased the potential N mineralization pool. Sustainable management practices that promote the persistence of these species in plant community are important to maintain soil fertility on semiarid grasslands. |
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