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Zirondi HL, Ooi MKJ, Fidelis A. Short-term fire exclusion affects germination and seed traits in tropical savannas. PLANT BIOLOGY (STUTTGART, GERMANY) 2024. [PMID: 38940062 DOI: 10.1111/plb.13678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 05/07/2024] [Indexed: 06/29/2024]
Abstract
In fire-prone ecosystems, plant traits are influenced by the fire regime, thus reproduction and establishment can be altered by this disturbance. Changes in fire frequency and history can therefore influence seed and germination traits. We investigated the effects of short-term fire exclusion on seed and germination traits of species from tropical open savannas. Seeds from 27 species were collected from two areas with distinct fire histories: recently and frequently burned (RB) or unburned for 5 to 7 years (E). Seeds from both areas underwent germination trials under optimal conditions for 30 days. Also, 10 species were exposed to high temperature treatments (100 or 200 °C) and seed and germination traits measured. Comparisons were then made for each trait, analysing each species separately, between the two areas. Approximately 85% of species studied had at least one of their germination traits altered in the RB area compared to the E area. Clear differences included lower viability and faster germination in seeds from RB areas. Seed traits of 70% of measured species differed between the two areas. Our results show species-specific trait response to different fire histories. For example, faster germination and lower viability of seeds from RB plots suggest selection for faster maturing individuals and differences in resourcing, respectively, under a regime of frequent fire. This study provides insights into fire effects on regeneration responses of tropical savanna species and also points to the need for more studies evaluating the effects of fire history on seed traits.
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Affiliation(s)
- H L Zirondi
- Laboratory of Vegetation Ecology, Instituto de Biociências, Universidade Estadual Paulista - UNESP, São Paulo, Brazil
| | - M K J Ooi
- Centre for Ecosystem Science, School of Biological, Earth and Environmental Sciences, University of New South Wales (UNSW), Kensington, Australia
| | - A Fidelis
- Laboratory of Vegetation Ecology, Instituto de Biociências, Universidade Estadual Paulista - UNESP, São Paulo, Brazil
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Wieczorkowski JD, Lehmann CER, Archibald S, Banda S, Goyder DJ, Kaluwe M, Kapinga K, Larridon I, Mashau AC, Phiri E, Syampungani S. Fire facilitates ground layer plant diversity in a Miombo ecosystem. ANNALS OF BOTANY 2024; 133:743-756. [PMID: 38468311 PMCID: PMC11082521 DOI: 10.1093/aob/mcae035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 03/07/2024] [Indexed: 03/13/2024]
Abstract
BACKGROUND AND AIMS Little is known about the response of ground layer plant communities to fire in Miombo ecosystems, which is a global blind spot of ecological understanding. We aimed: (1) to assess the impact of three experimentally imposed fire treatments on ground layer species composition and compare it with patterns observed for trees; and (2) to analyse the effect of fire treatments on species richness to assess how responses differ among plant functional groups. METHODS At a 60-year-long fire experiment in Zambia, we quantified the richness and diversity of ground layer plants in terms of taxa and functional groups across three experimental fire treatments of late dry-season fire, early dry-season fire and fire exclusion. Data were collected in five repeat surveys from the onset of the wet season to the early dry season. KEY RESULTS Of the 140 ground layer species recorded across the three treatments, fire-maintained treatments contributed most of the richness and diversity, with the least number of unique species found in the no-fire treatment. The early-fire treatment was more similar in composition to the no-fire treatment than to the late-fire treatment. C4 grass and geoxyle richness were highest in the late-fire treatment, and there were no shared sedge species between the late-fire and other treatments. At a plot level, the average richness in the late-fire treatment was twice that of the fire exclusion treatment. CONCLUSIONS Heterogeneity in fire seasonality and intensity supports diversity of a unique flora by providing a diversity of local environments. African ecosystems face rapid expansion of land- and fire-management schemes for carbon offsetting and sequestration. We demonstrate that analyses of the impacts of such schemes predicated on the tree flora alone are highly likely to underestimate impacts on biodiversity. A research priority must be a new understanding of the Miombo ground layer flora integrated into policy and land management.
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Affiliation(s)
- Jakub D Wieczorkowski
- School of GeoSciences, The University of Edinburgh, Edinburgh EH8 9XP, UK
- Tropical Diversity, Royal Botanic Garden Edinburgh, Edinburgh EH3 5LR, UK
| | - Caroline E R Lehmann
- School of GeoSciences, The University of Edinburgh, Edinburgh EH8 9XP, UK
- Tropical Diversity, Royal Botanic Garden Edinburgh, Edinburgh EH3 5LR, UK
- Centre for African Ecology, School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg 2050, South Africa
| | - Sally Archibald
- Centre for African Ecology, School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg 2050, South Africa
| | - Sarah Banda
- Herbarium, Division of Forest Research, Forestry Department, PO Box 22099, Kitwe, Zambia
| | - David J Goyder
- Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AE, UK
| | - Mokwani Kaluwe
- Herbarium, Division of Forest Research, Forestry Department, PO Box 22099, Kitwe, Zambia
| | - Kondwani Kapinga
- Dag Hammarskjöld Institute for Peace and Conflict Studies – Environment, Sustainable Development and Peace, Copperbelt University, PO Box 21692, Kitwe, Zambia
| | | | - Aluoneswi C Mashau
- Centre for African Ecology, School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg 2050, South Africa
- Foundational Research and Services, South African National Biodiversity Institute (SANBI), Private Bag X101, Pretoria 0184, South Africa
| | - Elina Phiri
- Herbarium, Division of Forest Research, Forestry Department, PO Box 22099, Kitwe, Zambia
| | - Stephen Syampungani
- Oliver R Tambo Africa Research Chair Initiative for Environment and Development, Copperbelt University, PO Box 21692, Kitwe, Zambia
- Department of Plant and Soil Sciences, University of Pretoria, Private Bag X20, Hatfield, Pretoria 0028, South Africa
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Buisson E, Archibald S, Fidelis A, Suding KN. Ancient grasslands guide ambitious goals in grassland restoration. Science 2022; 377:594-598. [PMID: 35926035 DOI: 10.1126/science.abo4605] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Grasslands, which constitute almost 40% of the terrestrial biosphere, provide habitat for a great diversity of animals and plants and contribute to the livelihoods of more than 1 billion people worldwide. Whereas the destruction and degradation of grasslands can occur rapidly, recent work indicates that complete recovery of biodiversity and essential functions occurs slowly or not at all. Grassland restoration-interventions to speed or guide this recovery-has received less attention than restoration of forested ecosystems, often due to the prevailing assumption that grasslands are recently formed habitats that can reassemble quickly. Viewing grassland restoration as long-term assembly toward old-growth endpoints, with appreciation of feedbacks and threshold shifts, will be crucial for recognizing when and how restoration can guide recovery of this globally important ecosystem.
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Affiliation(s)
- Elise Buisson
- Institut Méditerranéen de Biodiversité et d'Ecologie, Avignon Université, CNRS, IRD, Aix Marseille Université, 84911 Avignon, France
| | - Sally Archibald
- Centre for African Ecology, School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg 2050, South Africa
| | - Alessandra Fidelis
- Instituto de Biociências, Lab of Vegetation Ecology, Universidade Estadual Paulista (UNESP), Rio Claro 13506-900, Brazil
| | - Katharine N Suding
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA.,Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO, USA
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