Changes of the forest-savanna boundary in Brazilian Amazonia during the Holocene revealed by stable isotope ratios of soil organic carbon
The possibility of ecosystem boundary changes in northern Brazilian Amazonia during the Holocene period was investigated using soil organic carbon isotope ratios. Determination of past and present fluctuations of the forest-savanna boundary involved the measurement of natural 13C isotope abundance,...
| Autor principal: | Desjardins, Thierry |
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| Outros Autores: | Carneiro Filho, Arnaldo, Mariotti, André, Chauvel, Armand, Girardin, Cyril |
| Grau: | Artigo |
| Idioma: | English |
| Publicado em: |
Oecologia
2020
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| Acesso em linha: |
https://repositorio.inpa.gov.br/handle/1/19419 |
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oai:repositorio:1-19419 |
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oai:repositorio:1-19419 Changes of the forest-savanna boundary in Brazilian Amazonia during the Holocene revealed by stable isotope ratios of soil organic carbon Desjardins, Thierry Carneiro Filho, Arnaldo Mariotti, André Chauvel, Armand Girardin, Cyril Forest/savanna Boundary Forest/savanna Boundary Holocene Palaeoecology Soil Organic Carbon Stable Isotope Ratio Brazil, Amazonia The possibility of ecosystem boundary changes in northern Brazilian Amazonia during the Holocene period was investigated using soil organic carbon isotope ratios. Determination of past and present fluctuations of the forest-savanna boundary involved the measurement of natural 13C isotope abundance, expressed as δ13C, in soil organic matter (SOM). SOM 13C analyses and radiocarbon dating of charcoal fragments were carried out on samples derived from soil profiles taken along transects perpendicular to the ecotonal boundary. SOM δ13C values in the upper soil horizons appeared to be in equilibrium with the overlying vegetation types and did not point to a movement of the boundary during the last decades. However, δ13C values obtained from deeper savanna and forest soil layers indicated that the vegetation type has changed in the past. In current savanna soil profiles, we observed the presence of mid-Holocene charcoals derived from forest species: fire frequency at that time was probably greater, and more extensive savanna may have resulted. Isotope data and the presence of these charcoals thus suggest that the forest-savanna boundary has shifted significantly in the recent Holocene period, forest being more extensive during the early Holocene than today. During the middle Holocene, the forest could have strongly regressed, and fires appeared, with a maximum development of the savanna vegetation. At the beginning of the late Holocene, the forest may have invaded a part of this savanna, and fires occurred again. 2020-06-15T22:08:26Z 2020-06-15T22:08:26Z 1996 Artigo https://repositorio.inpa.gov.br/handle/1/19419 10.1007/BF00329051 en Volume 108, Número 4, Pags. 749-756 Restrito Oecologia |
| institution |
Instituto Nacional de Pesquisas da Amazônia - Repositório Institucional |
| collection |
INPA-RI |
| language |
English |
| topic |
Forest/savanna Boundary Forest/savanna Boundary Holocene Palaeoecology Soil Organic Carbon Stable Isotope Ratio Brazil, Amazonia |
| spellingShingle |
Forest/savanna Boundary Forest/savanna Boundary Holocene Palaeoecology Soil Organic Carbon Stable Isotope Ratio Brazil, Amazonia Desjardins, Thierry Changes of the forest-savanna boundary in Brazilian Amazonia during the Holocene revealed by stable isotope ratios of soil organic carbon |
| topic_facet |
Forest/savanna Boundary Forest/savanna Boundary Holocene Palaeoecology Soil Organic Carbon Stable Isotope Ratio Brazil, Amazonia |
| description |
The possibility of ecosystem boundary changes in northern Brazilian Amazonia during the Holocene period was investigated using soil organic carbon isotope ratios. Determination of past and present fluctuations of the forest-savanna boundary involved the measurement of natural 13C isotope abundance, expressed as δ13C, in soil organic matter (SOM). SOM 13C analyses and radiocarbon dating of charcoal fragments were carried out on samples derived from soil profiles taken along transects perpendicular to the ecotonal boundary. SOM δ13C values in the upper soil horizons appeared to be in equilibrium with the overlying vegetation types and did not point to a movement of the boundary during the last decades. However, δ13C values obtained from deeper savanna and forest soil layers indicated that the vegetation type has changed in the past. In current savanna soil profiles, we observed the presence of mid-Holocene charcoals derived from forest species: fire frequency at that time was probably greater, and more extensive savanna may have resulted. Isotope data and the presence of these charcoals thus suggest that the forest-savanna boundary has shifted significantly in the recent Holocene period, forest being more extensive during the early Holocene than today. During the middle Holocene, the forest could have strongly regressed, and fires appeared, with a maximum development of the savanna vegetation. At the beginning of the late Holocene, the forest may have invaded a part of this savanna, and fires occurred again. |
| format |
Artigo |
| author |
Desjardins, Thierry |
| author2 |
Carneiro Filho, Arnaldo Mariotti, André Chauvel, Armand Girardin, Cyril |
| author2Str |
Carneiro Filho, Arnaldo Mariotti, André Chauvel, Armand Girardin, Cyril |
| title |
Changes of the forest-savanna boundary in Brazilian Amazonia during the Holocene revealed by stable isotope ratios of soil organic carbon |
| title_short |
Changes of the forest-savanna boundary in Brazilian Amazonia during the Holocene revealed by stable isotope ratios of soil organic carbon |
| title_full |
Changes of the forest-savanna boundary in Brazilian Amazonia during the Holocene revealed by stable isotope ratios of soil organic carbon |
| title_fullStr |
Changes of the forest-savanna boundary in Brazilian Amazonia during the Holocene revealed by stable isotope ratios of soil organic carbon |
| title_full_unstemmed |
Changes of the forest-savanna boundary in Brazilian Amazonia during the Holocene revealed by stable isotope ratios of soil organic carbon |
| title_sort |
changes of the forest-savanna boundary in brazilian amazonia during the holocene revealed by stable isotope ratios of soil organic carbon |
| publisher |
Oecologia |
| publishDate |
2020 |
| url |
https://repositorio.inpa.gov.br/handle/1/19419 |
| _version_ |
1787141943472422912 |
| score |
11.755432 |