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Cao J, Li B, Qi R, Liu T, Chen X, Gao B, Liu K, Baskin CC, Zhao Z. Negative impacts of human disturbances on the seed bank of subalpine forests are offset by climatic factors. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 851:158249. [PMID: 36028043 DOI: 10.1016/j.scitotenv.2022.158249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 08/19/2022] [Accepted: 08/20/2022] [Indexed: 06/15/2023]
Abstract
Precipitation and temperature in the subalpine region have increased dramatically in recent decades due to global warming, and human disturbances have continued to impact the vegetation in the region. Seed bank plays an important role in population recovery, but there are few studies on the synergistic effects of human disturbances and climate change on seed bank. We analyzed the synergistic effects of human disturbances and climate change on seed bank samples from 20 sites in the subalpine coniferous forest region using grazing and logging as the disturbance intensity gradient and precipitation and temperature as climate variables. The species diversity of aboveground vegetation all changed significantly (p < 0.05) with precipitation, temperature and disturbance level, while the seed bank richness and density did not. Furthermore, the species composition of the seed bank varied significantly less than that of the aboveground vegetation at different levels of disturbance (p < 0.001). Thus, seed bank showed a strong buffering capacity against the risk of local extinction caused by environmental changes that shift the species composition and diversity of aboveground vegetation. In addition, soil and litter are important influences controlling seed bank density in subalpine forests, and the results of structural equation modelling suggest that both disturbance and climate change can indirectly regulate the seed bank by changing the physicochemical properties of soil and litter. We conclude that increases in precipitation and temperature driven by climate change can buffer the negative effects of disturbances on the seed bank.
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Affiliation(s)
- Jiahao Cao
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, LanZhou University, Lanzhou 730070, China; Institute of Forestry Science of Bailongjiang in Gansu Province, Lanzhou 730046, China; Gansu Bailongjiang National Forest Ecosystem Research Station, Zhouqu 746300, China
| | - Bo Li
- Institute of Forestry Science of Bailongjiang in Gansu Province, Lanzhou 730046, China; Gansu Bailongjiang National Forest Ecosystem Research Station, Zhouqu 746300, China.
| | - Rui Qi
- Institute of Forestry Science of Bailongjiang in Gansu Province, Lanzhou 730046, China; Gansu Bailongjiang National Forest Ecosystem Research Station, Zhouqu 746300, China
| | - Ting Liu
- Institute of Forestry Science of Bailongjiang in Gansu Province, Lanzhou 730046, China; Gansu Bailongjiang National Forest Ecosystem Research Station, Zhouqu 746300, China
| | - Xuelong Chen
- Institute of Forestry Science of Bailongjiang in Gansu Province, Lanzhou 730046, China; Gansu Bailongjiang National Forest Ecosystem Research Station, Zhouqu 746300, China
| | - Benqiang Gao
- Institute of Forestry Science of Bailongjiang in Gansu Province, Lanzhou 730046, China; Gansu Bailongjiang National Forest Ecosystem Research Station, Zhouqu 746300, China
| | - Kun Liu
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, LanZhou University, Lanzhou 730070, China
| | - Carol C Baskin
- Department of Biology, University of Kentucky, Lexington, USA; Department of Plant and Soil Sciences, University of Kentucky, Lexington, USA
| | - Zhigang Zhao
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, LanZhou University, Lanzhou 730070, China.
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Colón Carrión N, Troche CL, Arnold AE. Communities of endophytic fungi in a Puerto Rican rainforest vary along a gradient of disturbance due to Hurricane Maria. Ecol Evol 2022; 12:e9618. [PMID: 36532133 PMCID: PMC9750846 DOI: 10.1002/ece3.9618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 09/18/2022] [Accepted: 11/17/2022] [Indexed: 12/23/2022] Open
Abstract
Increases in the frequency and intensity of hurricanes influence the structure, function, and resilience of Caribbean forests. Trees in such forests harbor diverse fungal endophytes within leaves and roots. Fungal endophytes often are important for plant health and stress responses, but how their communities are impacted by hurricanes is not well known. We measured forest disturbance in Carite State Forest in Puerto Rico ca. 16 months after the passage of Hurricane Maria, a Category 4 storm. In three sites, each comprising three plots representing a local gradient of hurricane disturbance, we evaluated soil chemistry and used culture-free analyses to measure richness, phylogenetic diversity, and composition of endophyte communities in leaves and roots. We found that endophyte richness did not vary significantly among plant families or as a function of soil chemistry. Instead, leaf endophytes peaked in richness and decreased in phylogenetic diversity at intermediate levels of disturbance. Root endophytes did not show such variation, but both leaf- and root endophyte communities differed in species composition as a function of disturbance across the forest. Locations with less disturbance typically hosted distinctive assemblages of foliar endophytes, whereas more disturbed locations had more regionally homogeneous endophyte communities. Together, our results show that changes in endophyte richness and phylogenetic diversity can be detected in aboveground tissues more than a year after major storms. In turn, pervasive shifts in endophyte community composition both aboveground and belowground suggest a subtle and lasting effect of hurricanes that merits further study, potentially contributing to the promotion of spatially heterogeneous endophyte assemblages at a landscape scale in these diverse island forests.
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Affiliation(s)
| | | | - A. Elizabeth Arnold
- School of Plant SciencesUniversity of ArizonaTucsonArizonaUSA
- Department of Ecology and Evolutionary BiologyUniversity of ArizonaTucsonArizonaUSA
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Bibbo S, Lodge DJ. A Preconditioning Paradox: Contrasting Effects of Initial Phyllosphere and Early Leaf Decomposer Microfungi on Subsequent Colonization by Leaf Decomposing Non-Unit-Restricted Basidiomycetes. J Fungi (Basel) 2022; 8:jof8090903. [PMID: 36135628 PMCID: PMC9501227 DOI: 10.3390/jof8090903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 08/20/2022] [Accepted: 08/23/2022] [Indexed: 11/30/2022] Open
Abstract
Fungal interactions during leaf decomposition can facilitate or inhibit other fungi. This experiment focused on whether preconditioning of leaf litter by microfungi that were confined to one leaf (Unit-Restricted) made leaf litter less likely to be colonized and decomposed by basidiomycetes that bind litter into mats (Non-Unit-Restricted) than non-preconditioned litter. Leaves of Manilkara bidentata in litterbags were preconditioned by incubating them for 0, 1, 2 or 3 months in flat litter/seed rain baskets 10 cm above the forest floor to avoid colonization by basidiomycete fungi. Preconditioned and non-preconditioned leaves were transferred to 5 replicate basidiomycete fungal mats of Gymnopus johnstonii for 6 weeks. Both attachment by basidiomycete fungi and percent mass loss after 6 weeks decreased significantly with increasing preconditioning time. In non-preconditioned leaves, gamma irradiation did not affect mass loss or percent white-rot despite having significantly increased numbers of basidiomycete fungal connections as compared to non-irradiated leaves. In non-preconditioned leaves, more basidiomycetes attachmented to non-irradiated than irradiated leaves suggest facilitation by phyllosphere microfungi. While basidiomycete colonization was initially facilitated by phyllosphere fungi, we inferred that degradation of resource quality led to fewer fungal attachments and less mass loss after 1–3 months of preconditioning by microfungi. The date suggest there is a 1-month time window for basidiomycete fungi to incorporate fallen leaves into their litter mats.
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Affiliation(s)
- Silvia Bibbo
- Plant Ecology & Evolution, Evolutionary Biology Center, Uppsala University, SE-751 05 Uppsala, Sweden
- Correspondence:
| | - D. Jean Lodge
- Department of Plant Pathology, Odum School of Ecology, University of Georgia, Athens, GA 30605, USA
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Moreno II, Barberena‐Arias MF, González G, Lodge DJ, Cantrell SA. Canopy opening increases leaf‐shredding arthropods and nutrient mineralization but not mass loss in wet tropical forest. Ecosphere 2022. [DOI: 10.1002/ecs2.4084] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Ivia I. Moreno
- Department of Biology Universidad Ana G Méndez, Gurabo Campus Gurabo Puerto Rico
| | | | - Grizelle González
- USDA Forest Service International Institute of Tropical Forestry Río Piedras Puerto Rico
| | - D. Jean Lodge
- USDA Forest Service, Northern Research Station Luquillo Puerto Rico
| | - Sharon A. Cantrell
- Department of Biology Universidad Ana G Méndez, Gurabo Campus Gurabo Puerto Rico
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