Phenological cycles in the Pantanal woody communities: Responses to climate and soil moisture seasonality

RESEARCH ARTICLE Phenological cycles in the Pantanal woody communities: Responses to climate and soil moisture seasonality Julia ArieiraID1,2*, Karl-L. SchuchmannID2,3,4, Arnildo Pott5, Michelle D. Lanssanova6, Ana Silvia O. TissianiID2, Osvaldo Borges Pinto JuniorID6, Marinêz Isaac Marques2,4 1 Science Panel for the Amazon, São Jose´ dos Campos, São Paulo, Brazil, 2 National Institute for Science and Technology in Wetlands (INCT-INAU), Centro de Pesquisa do Pantanal–CPP, Federal University of Mato Grosso (UFMT), Computational Bioacoustics Research Unit (CO.BRA), Cuiaba´ , Mato Grosso, Cuiaba´, Brazil, 3 Zoological Research Museum A. Koenig (ZFMK), Ornithology, Bonn, Germany, 4 Institute of Biosciences, Postgraduate Program in Zoology, Federal University of Mato Grosso, Cuiaba´, Mato Grosso, Brazil, 5 Institute of Biosciences, Federal University of Mato Grosso do Sul (UFMS), Campo Grande, Mato Grosso do Sul, Brazil, 6 University of Cuiaba´-UNIC, Cuiaba´ , Mato Grosso, Brazil * juarieira@gmail.com Abstract This study investigated the influences of regional climate and soil moisture conditions on the vegetative and reproductive cycles of seven savanna and forest vegetation communities of the Pantanal Mato-grossense. Circular analysis of the phenological data revealed the occur- rence of interspecific synchronism and seasonal responses in vegetative and reproductive activities, with flowering patterns differing the most between communities. Leaf shedding intensity events in communities were closely linked to climatic seasonality. Over half of the

individuals were semideciduous or deciduous, with leaf drop intense events predominantly triggered by drier, warmer conditions. The annual flood pulse further constrains woody plants, influencing deciduousness and serving as a strategy to mitigate soil water stress. The preceding climatic signal announcing cold fronts was a relevant determinant of flower- ing events for many communities. Climate and soil seasonality had limited influences on fruiting phenology across the various vegetation communities. The asynchronous response of phenological cycles to surface soil moisture seasonality highlights the diverse habitat hydrodynamics and its interactions with the plant communities that may decouple leaf fall, flowering, and fruiting from surface soil water availability. The unique phenological response of the Pantanal’s woody communities to the hydro-climatic cycle sets it apart from other non-flooded savannas of tropical South America. This response involves the intricate inter- play between phenological dynamism and alternating drought and wet-flooded phases. Introduction Tropical ecosystems face unprecedented crises. Accelerated changes in global and regional cli- mate and land cover degradation driven by unsustainable models of development are now PLOS ONE PLOS ONE | https://doi.org/10.1371/journal.pone.0316011 February 7, 2025 1 / 30 a1111111111 a1111111111 a1111111111 a1111111111 a1111111111 OPEN ACCESS Citation: Arieira J, Schuchmann K-L, Pott A, Lanssanova MD, Tissiani ASO, Pinto Junior OB, et al. (2025) Phenological cycles in the Pantanal

woody communities: Responses to climate and soil moisture seasonality. PLoS ONE 20(2): e0316011. https://doi.org/10.1371/journal. pone.0316011 Editor: Angelina Martı´nez-Yrı´zar, UNAM, MEXICO Received: April 4, 2024 Accepted: December 4, 2024 Published: February 7, 2025 Peer Review History: PLOS recognizes the benefits of transparency in the peer review process; therefore, we enable the publication of all of the content of peer review and author responses alongside final, published articles. The editorial history of this article is available here: https://doi.org/10.1371/journal.pone.0316011 Copyright: © 2025 Arieira et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All relevant data are within the manuscript and its Supporting Information files.