Hydraulic lift as a determinant of tree-grass coexistence on savannas
© 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.
Veröffentlicht in: | The New phytologist. - 1979. - 207(2015), 4 vom: 30. Sept., Seite 1038-51 |
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Format: | Online-Aufsatz |
Sprache: | English |
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2015
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Zugriff auf das übergeordnete Werk: | The New phytologist |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. coexistence competition facilitation fire hydraulic lift savanna Soil mehr... |
Zusammenfassung: | © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust. The coexistence of woody plants and grasses in savannas is determined by a complex set of interacting factors that determine access to resources and demographic dynamics, under the control of external drivers and vegetation feedbacks with the physical environment. Existing theories explain coexistence mainly as an effect of competitive relations and/or disturbances. However, theoretical studies on the way facilitative interactions resulting from hydraulic lift affect tree-grass coexistence and the range of environmental conditions in which savannas are stable are still lacking. We investigated the role of hydraulic lift in the stability of tree-grass coexistence in savannas. To that end, we developed a new mechanistic model that accounts for both competition for soil water in the shallow soil and fire-induced disturbance. We found that hydraulic lift favors grasses, which scavenge the water lifted by woody plants. Thus, hydraulic lift expands (at the expenses of woodlands) the range of environmental conditions in which savannas are stable. These results indicate that hydraulic lift can be an important mechanism responsible for the coexistence of woody plants and grasses in savannas. Grass facilitation by trees through the process of hydraulic lift could allow savannas to persist stably in mesic regions that would otherwise exhibit a forest cover |
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Beschreibung: | Date Completed 04.05.2016 Date Revised 30.09.2020 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 1469-8137 |
DOI: | 10.1111/nph.13431 |