Nutrient cycling between soil and leaf litter in the Cerrado (Brazilian savanna) on eutrophic and dystrophic Neosols

Abstract

We evaluated nutrient cycling by measuring leaf litter production and decomposition in the Brazilian savanna (cerrado sensu stricto) on eutrophic (calcareous) and dystrophic (arenitic) Neosols over the same spatiotemporal scale. We installed three transects in the Cerrado with plots in each Neosol type. Areas along the transects were randomly chosen for determining soil chemical properties, and accumulated leaf litter was collected monthly for a year for analysis. We used litter bags to test for a correlation between loss of dry mass and nutrient release. Th e calcareous cerrado had higher levels of macronutrients, higher pH, and lower Al compared to the arenitic cerrado. Th e estimated annual release of leaf litter nutrients in kg ha -1 yr -1 was higher in the calcareous cerrado. Nutrient concentration was signifi cantly higher in diff erent months in the calcareous cerrado, except for S and N. In general, the loss of dry mass was not correlated with nutrient release. Calcareous Neosol is unique to the cerrado sensu stricto, and retains more nutrients and facilitates higher leaf litter chemical quality than cerrado of the same physiognomy on dystrophic soils. Nutrient release is not always related to loss of dry mass, regardless of the amount of leaf litter.

Nitrogen dynamics in small watersheds in the Atlantic Forest and Cerrado in Northeastern Brazil

“…The biogeochemical processes that occur in the soil reflect the availability of nutrients within an ecosystem, with the production and decomposition of litter being an important way of exporting nutrients from terrestrial to aquatic ecosystems (García-Palacios, McKie, Handa, Frainer, & Hättenschwiler, 2015). In general, leaves are the predominant fractions in the litterfall and provide an important role in the availability of nutrients in the soil (Alves et al, 2018;Oliveira et al, 2015) as well as in streams, constituting more than 50% of the allochthonous particulate organic material (Gonçalves et al, 2006).…”

Geoambientes e relação solo-vegetação no norte de Minas Gerais

“…Elevados teoresde Ca 2+ no solo podem proporcionar aumento no pH e, consequentemente aumento na capacidade de troca catiônica; o que resulta no aumento da disponibilidade de macronutrientes para espécies vegetais, principalmente as calcífilas(DE SOUZA et al,2019). Entretanto, de acordo comAlves et al (2018), altos teores do cátion no solo podem causar estresse fisiológico e problemas de crescimento às espécies vegetais. De acordo com os autores, nutrientes como, P, K + e Fe em contato do cálcio podem originar sais solúveis e torná-los indisponíveis às plantas.O segundo grupo corresponde às espécies que apresentaram alta correlação com solos ácidos, arenosos, com as maiores concentrações de Fe e Al 3+ , as quais apresentam as maiores abundâncias no geoambiente com a maior altitude (CENR).…”