Savannas can functionally turn into forests in the Amazonia/Cerrado transition
DOI:
https://doi.org/10.37002/biodiversidadebrasileira.v11i3.1764Keywords:
Cerradão, Dense Cerrado, Marimon-Hay, decomposition constant k, root matAbstract
Adjacent forest formations are ecotones that can reveal changes in the vertical structure of tropical biomes e.g., Cerrado (brazilian Savanna). Litterfall is a metric that shows some of these alterations. Thus, we investigated key functional aspects of a Cerradão (savanna forest) and a savanna (Dense Cerrado) in the Amazonia/Cerrado transition. We evaluated the litter layer, leaf decomposition, and root mat to verify to what extent these parameters are related to ecosystem functioning of the two distinct formations, savanna, and forest. The integrated litter layer/root mat system is the main pre-condition for ecosystem functioning and trophic balance of tropical forests on dystrophic soils. The litter layer, root mat, and leaf decomposition rates were very similar in both ecosystems, including carbon release from the litter layer, despite the differences in floristic and structure of both vegetations. These similarities indicate densification of the adjacent Cerrado with a pre-structuration of a forest-like ecosystem functioning, mainly due to the no fire event. Our findings suggest that savanna ecosystems on dystrophic soils of the Amazonia/Cerrado transition have high potential to establish the trophic functional conditions to support a forest community in the absence of fire and climate changes. As long as the current climate does not change to drier and hotter conditions (e.g., increased El Niño anomalies), ecological succession can be triggered and savannas can functionally turn into forests, with an increase in carbon stocks of the ecosystem.
References
Andrade EM, Guerreiro MJS, Palácio HAQ, Campos DA. Ecohydrology in a Brazilian tropical dry forest: thinned vegetation impact on hydrological functions and ecosystem services, Journal of Hydrology: Regional Studies, 27(100649):1-13, 2020.
Barbosa RI, Silva SJR, Souza CM, Pimentel TP, Fearnside PM. Root biomass, root:shoot ratio and belowground carbon stocks in the open savannahs of Roraima, Brazilian Amazonia. Australian Journal of Botany, 60(5): 405-416, 2012.
Bocock KL, Gilbert OJ. The disappearance of litter under different woodland conditions. Plant Soil, 9: 179-185, 1957.
Brasil LS, Giehl NFS, Santos JO, Santos AO, Marimon BS, Marimon-Junior BH. Efeito de borda sobre a camada de serapilheira em área de Cerradão no leste de Mato Grosso. Biotemas, 37: 37-47, 2013.
Doughty EC, et al. Drought impact on forest carbon dynamics and fluxes in Amazonia. Nature, 519(7041): 78-82, 2015.
Empresa Brasileira de Pesquisa Agropecuária - EMBRAPA. 2018. Sistema brasileiro de classificação de solos. 5 ed. Embrapa. 356p.
Garcia AS et al. Assessing land use/cover dynamics and exploring drivers in the Amazon's arc of deforestation through a hierarchical, multi-scale and multi-temporal classification approach. Remote Sensing Applications: Society and Environment, 15: 100233, 2019.
Franczak DD, Marimon BS, Marimon-Junior BH, Mews HA, Maracahipes L. Oliveira EA. Changes in the structure of a savanna forest over a six-year period in the Amazon-Cerrado transition, Mato Grosso state, Brazil. Rodriguésia, 62(2): 425-436, 2011.
Higuchi N, Santos J, Ribeiro RJ, Minette L, Biot Y. Biomassa da parte aérea da vegetação de floresta tropical úmida de terra firme da Amazônia Brasileira. Acta Amazon, 28(2): 153-165, 1998.
Hobbie SE. Plant species effects on nutrient cycling: revisiting litter feedbacks. Trends Ecology Evolution, 30(6): 357-363, 2015.
Hoffmann WA, Geiger EL, Gotsch SG, Rossato, DR, Silva LCR, Lau OL. Ecological thresholds at the savanna-forest boundary: how plant traits, resources and ï¬re govern the distribution of tropical biomes. Ecology Letters, 15(7): 759-768, 2012a.
Hoffmann WA, Jaconis SY, Mckinley KL, Geiger EL, Gotsch SG, Franco AC. Fuels or microclimate? Understanding the drivers of ï¬re feedbacks at savanna-forest boundaries. Austral Ecology, 37(6): 634-643, 2012b.
Hoffmann WA, Orthen B, Franco AC. Constraints to seedling success of savanna and forest trees across the savanna-forest boundary. Oecologia, Berlin, 140: 252-260, 2004.
Jacobson TKB, Bustamante MMC. 2014. Leaf litter decomposition and nutrient release under nitrogen, phosphorus and nitrogen plus phosphorus additions in a savanna in Central Brazil, p. 155-163. In: Sutton MA, Manso KE, Sheppard LJ, Sverdrup H, Haeuber R, Hicks, WK (eds.). Nitrogen deposition, critical loads and biodiversity. Springer Dordrecht. 535p.
Jobbágy EG, Jackson RB. The vertical distribution of soil organic carbon and its relation to climate and vegetation. Ecological Applications, 10(2): 423-436, 2000.
Malhi Y, Doughty C, Galbraith D. The allocation of ecosystem net primary productivity in tropical forests. Philosophical Transactions of the Royal Society B: Biological Sciences, 366: 3225-3245, 2011.
Marimon BS, et al. Disequilibrium and hyperdynamic tree turnover at the forest-cerrado transition zone in southern Amazonia. Plant Ecology Diversity, 7(1-2): 281-292, 2014.
Marimon-Junior BH, Haridasan M. Comparação da vegetação arbórea e características edáficas de um cerradão e um cerrado sensu stricto em áreas adjacentes sobre solo distrófico no leste de Mato Grosso, Brasil. Acta Botanica Brasilica, 19: 913-926, 2005.
Marimon-Junior BH, Hay JD. A new instrument and protocol for measurement and collection of quantitative samples of the litter layer in forests. Forest Ecology Management, 255(7): 2244-2250, 2008.
Marques EQ, Marimon-Junior BH, Matricardi EAT, Mews HA, Colli GR. Redefining the Cerrado-Amazonia transition: implications for conservation. Biodiversity and Conservation, 29: 501-1517, 2019.
Morandi OS, et al. Vegetation succession in the Cerrado-Amazonian forest transition zone of Mato Grosso state, Brazil. Edinburgh Journal of Botany, 73(1): 83-93, 2015.
Neves LFS, Marimon BS, Anderson LO, Neves SMAS. Dinâmica de fogo no parque estadual do Araguaia, zona de transição Amazônia-Cerrado. Raega - O Espaço Geográfico em Análise, 44: 85-103, 2018.
Oliveira B, Marimon-Junior BH, Mews HA, Valadão MBX, Marimon BS. Unraveling the ecosystem functions in the Amazonia-Cerrado transition: evidence of hyperdynamic nutrient cycling. Plant Ecology, 218(2): 225-239, 2017.
Oliveira, RS, et al. Deep root function in soil water dynamics in cerrado savannas of central Brazil. Functional Ecology, 19(4): 574-581, 2005.
Olson JS. Energy storage and the balance of producers and decomposers in ecological systems. Ecology 44(2): 322-332, 1963.
Passos FB, et al. Savanna turning into forest: concerted vegetation change at the ecotone between the Amazon and "Cerrado" biomes. Brazilian Journal of Botany, 41: 611-619, 2018.
Peixoto KS, et al. Assessing the effects of rainfall reduction on litterfall and the litter layer in phytophysiognomies of the Amazonia-Cerrado transition. Brazilian Journal of Botany, 41: 589-600, 2018.
Ratter JA, Richards PW, Argent G, Gifford DR. Observations on the vegetation of the northeastern Mato Grosso: I. The woody vegetation types of the Xavantina-Cachimbo Expedition area. Philosophical Transactions of the Royal Society of London B, 266: 449-492, 1973.
Ribeiro JF, Walter BMT. 1998. Fitofisionomias do Bioma Cerrado. p. 87-166. In: Sano SM, Almeida SP. (eds.). Cerrado: ambiente e flora. Brasília, Embrapa Cerrados. 556p.
Ribeiro JF, Walter BMT. 2008. As principais fitofisionomias do Bioma Cerrado. p.151-212. In: Sano SM, Almeida SP, Ribeiro JF (eds.). Cerrado: ecologia e flora. Planaltina, Embrapa. 406p.
Ribeiro FP, et al. Litter Dynamics in Eucalyptus and Native Forest in the Brazilian Cerrado. Journal of Agricultural Science, 10(11): 1-15, 2018.
Sayer EJ, Tanner EVJ, Cheesman AW. Increased litterfall changes fine root distribution in a moist tropical forest. Plant and Soil, 281(1-2): 5-13, 2006.
Silva FMA, Evangelista BA, Malaquias JV, Muller AG, Oliveira AD. 2017. Boletim de Pesquisa e Desenvolvimento 340: análise temporal de variáveis climáticas monitoradas entre 1974 e 2013 na Estação Principal da Embrapa. Embrapa Cerrados. 121p.
Sitch S, et al. Recent trends and drivers of regional sources and sinks of carbon dioxide. Biogeosciences 12(3): 653-679, 2015.
Sochacki SJ, Ritson P, Brand B, Harper RJ, Dell B. Accuracy of tree root biomass sampling methodologies for carbon mitigation projects. Ecological Engineering, 98: 264-274, 2017.
Souza JV, Ribeiro FC, Bussinguer, AP, Hodecker BER, Valadão MBX, Gatto A. Stock and litter decomposition in different vegetation types and eucalypt plantations in the Cerrado region, Brazil. Australian Journal of Basic and Applied Sciences 10(18): 74-81, 2016.
Speleta JFE, Clark, DA. Multi-scale variation in fine-root biomass in a Tropical Rain Forest: a seven-year study. Ecological Monographs, 77(3): 377-404, 2007.
Valadão MBX, Marimon-Junior BH, Oliveira B, Lucio NW, Souza MGR, Marimon BS. Biomass hyperdynamics as a key modulator of forest self-maintenance in a dystrophic soil in the Amazonia-Cerrado transition. Scientia Forestalis, 44(110): 475-485, 2016.
Vitousek PM, Sanford RL. Nutrient cycling in moist tropical forest. Annual Review of Ecology Systematics, 17: 137-167, 1986.
Xu X, Jia G, Zhang X, Riley WJ, Xue Y. Climate regime shift and forest loss amplify fire in Amazonian forests. Global Change Biology, 26(10): 5874-5885, 2020.
Zar JH. 2010. Biostatistical analysis. 5 ed. Prentice Hall. 718p.
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