Le Bienfaiteur Takougoum Sagang, Imma Tcheferi, Pierre Ploton, Moses Libalah, Murielle Simo-Droissart, Nelly Sirri, Gilles Dauby, Eric Ngansop, Jean Pierre Bissek, Narcisse Kamdem, Gislain I I Mofack, Donatien Zebaze, Hugo Leblanc, Fabrice Djonko, Bonaventure Sonké, Nicolas Barbier, Pierre Couteron
{"title":"土壤与其他环境变量之间的相互作用调节了中非潮湿热带草原的森林扩张和生态区动态。","authors":"Le Bienfaiteur Takougoum Sagang, Imma Tcheferi, Pierre Ploton, Moses Libalah, Murielle Simo-Droissart, Nelly Sirri, Gilles Dauby, Eric Ngansop, Jean Pierre Bissek, Narcisse Kamdem, Gislain I I Mofack, Donatien Zebaze, Hugo Leblanc, Fabrice Djonko, Bonaventure Sonké, Nicolas Barbier, Pierre Couteron","doi":"10.1098/rspb.2024.1120","DOIUrl":null,"url":null,"abstract":"<p><p>Forest expansion into savanna is a pervasive phenomenon in West and Central Africa, warranting comparative studies under diverse environmental conditions. We collected vegetation data from the woody and grassy components within 73 plots of 0.16 ha distributed along a successional gradient from humid savanna to forest in Central Africa. We associated spatially collocated edaphic parameters and fire frequency derived from remote sensing to investigate their combined influence on the vegetation. Soil texture was more influential in shaping savanna structure and species distribution than soil fertility, with clay-rich soils promoting higher grass productivity and fire frequency. Savanna featuring woody aboveground biomass surpassing 40 Mg ha<sup>-1</sup> could escape the grass-fire feedback loop, by depressing grass biomass below 4 Mg ha<sup>-1</sup>. This thicker woody layer also favoured the establishment of fire-tolerant forest pioneers, which synergically contributed to the expansion of forests. Conversely, savannas below this fire suppression threshold sustained a balance between trees and grasses through the grass-fire feedback mechanism. This hysteresis loop, particularly pronounced on clayey soils, suggests that the contrast between grassy savanna and young forests might represent alternative ecosystem states, although savannas with low woody biomass remained vulnerable to forest edge encroachment.</p>","PeriodicalId":20589,"journal":{"name":"Proceedings of the Royal Society B: Biological Sciences","volume":"291 2033","pages":"20241120"},"PeriodicalIF":3.8000,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11521620/pdf/","citationCount":"0","resultStr":"{\"title\":\"Interactions between soil and other environmental variables modulate forest expansion and ecotone dynamics in humid savannas of Central Africa.\",\"authors\":\"Le Bienfaiteur Takougoum Sagang, Imma Tcheferi, Pierre Ploton, Moses Libalah, Murielle Simo-Droissart, Nelly Sirri, Gilles Dauby, Eric Ngansop, Jean Pierre Bissek, Narcisse Kamdem, Gislain I I Mofack, Donatien Zebaze, Hugo Leblanc, Fabrice Djonko, Bonaventure Sonké, Nicolas Barbier, Pierre Couteron\",\"doi\":\"10.1098/rspb.2024.1120\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>Forest expansion into savanna is a pervasive phenomenon in West and Central Africa, warranting comparative studies under diverse environmental conditions. We collected vegetation data from the woody and grassy components within 73 plots of 0.16 ha distributed along a successional gradient from humid savanna to forest in Central Africa. We associated spatially collocated edaphic parameters and fire frequency derived from remote sensing to investigate their combined influence on the vegetation. Soil texture was more influential in shaping savanna structure and species distribution than soil fertility, with clay-rich soils promoting higher grass productivity and fire frequency. Savanna featuring woody aboveground biomass surpassing 40 Mg ha<sup>-1</sup> could escape the grass-fire feedback loop, by depressing grass biomass below 4 Mg ha<sup>-1</sup>. This thicker woody layer also favoured the establishment of fire-tolerant forest pioneers, which synergically contributed to the expansion of forests. Conversely, savannas below this fire suppression threshold sustained a balance between trees and grasses through the grass-fire feedback mechanism. This hysteresis loop, particularly pronounced on clayey soils, suggests that the contrast between grassy savanna and young forests might represent alternative ecosystem states, although savannas with low woody biomass remained vulnerable to forest edge encroachment.</p>\",\"PeriodicalId\":20589,\"journal\":{\"name\":\"Proceedings of the Royal Society B: Biological Sciences\",\"volume\":\"291 2033\",\"pages\":\"20241120\"},\"PeriodicalIF\":3.8000,\"publicationDate\":\"2024-10-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11521620/pdf/\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Proceedings of the Royal Society B: Biological Sciences\",\"FirstCategoryId\":\"99\",\"ListUrlMain\":\"https://doi.org/10.1098/rspb.2024.1120\",\"RegionNum\":1,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"2024/10/30 0:00:00\",\"PubModel\":\"Epub\",\"JCR\":\"Q1\",\"JCRName\":\"BIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Proceedings of the Royal Society B: Biological Sciences","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1098/rspb.2024.1120","RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/10/30 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"BIOLOGY","Score":null,"Total":0}
Interactions between soil and other environmental variables modulate forest expansion and ecotone dynamics in humid savannas of Central Africa.
Forest expansion into savanna is a pervasive phenomenon in West and Central Africa, warranting comparative studies under diverse environmental conditions. We collected vegetation data from the woody and grassy components within 73 plots of 0.16 ha distributed along a successional gradient from humid savanna to forest in Central Africa. We associated spatially collocated edaphic parameters and fire frequency derived from remote sensing to investigate their combined influence on the vegetation. Soil texture was more influential in shaping savanna structure and species distribution than soil fertility, with clay-rich soils promoting higher grass productivity and fire frequency. Savanna featuring woody aboveground biomass surpassing 40 Mg ha-1 could escape the grass-fire feedback loop, by depressing grass biomass below 4 Mg ha-1. This thicker woody layer also favoured the establishment of fire-tolerant forest pioneers, which synergically contributed to the expansion of forests. Conversely, savannas below this fire suppression threshold sustained a balance between trees and grasses through the grass-fire feedback mechanism. This hysteresis loop, particularly pronounced on clayey soils, suggests that the contrast between grassy savanna and young forests might represent alternative ecosystem states, although savannas with low woody biomass remained vulnerable to forest edge encroachment.
期刊介绍:
Proceedings B is the Royal Society’s flagship biological research journal, accepting original articles and reviews of outstanding scientific importance and broad general interest. The main criteria for acceptance are that a study is novel, and has general significance to biologists. Articles published cover a wide range of areas within the biological sciences, many have relevance to organisms and the environments in which they live. The scope includes, but is not limited to, ecology, evolution, behavior, health and disease epidemiology, neuroscience and cognition, behavioral genetics, development, biomechanics, paleontology, comparative biology, molecular ecology and evolution, and global change biology.