Different Patterns Of Nutrient Cycling In Contiguous Phytophysiognomies Of Atlantic Forest, Brazil

Abstract

The present study aimed to evaluate fine aboveground litterfall, deposition of nitrogen and phosphorus from total litterfall and leaf litter decomposition in areas of tall forest (Mata Alta) and low forest on sandy soils (Mussununga) in southeastern Brazil. Fine litterfall was collected monthly for two years (from June/2007 to May/2009) in 10 conical collectors (0.25 m 2) in each phytophysiognomy (1 ha plots). The material was subsequently separated into leaves, branches, flowers and fruits, and unidentified material. Leaf decomposition rates were evaluated using 15 litterbags, three of which were collected every 30 days. Higher litterfall occurred in both phytophysiognomies during the rainy season, with leaves predominating. The lowest litterfall, nutrient input, and leaf litter decomposition values appeared to be nutrient conservation strategies, contributing to the ecological functioning of the Mussununga where soil fertility was lower than in the Mata Alta.

Contribution of Pseudobombax aff. petropolitanum to Nutrient Cycling in Woody Vegetation from a Neotropical Inselberg

“…The continuous fine litterfall throughout the year in the inselberg woody vegetation, although seasonality is observed in this process, is a phenomenon commonly observed in the Atlantic Forest biome, regardless of phytophysiognomy, successional stage, altitude, and distance from the edge towards the interior of plant community (Martinelli et al, 2017;Sousa-Neto et al, 2017;Camara et al, 2018aCamara et al, , 2018bMachado et al, 2018;Schumacher et al, 2018;Carvalho et al, 2019;Araújo et al, 2020;Dick & Schumacher, 2020;Menezes et al, 2020;Câmara et al, 2021;Lagemann et al, 2022). The maximum monthly litterfall in inselberg (PP, OS, total litterfall) verified in March 2012 (end of the rainy season and beginning of the dry season) was probable a function of low accumulated precipitation, which was only 74.40 mm (approximately 7.2 % of annual precipitation).…”

“…This result showed the importance of woody vegetation for carbon cycling on inselberg, despite its small vegetation structure characterized by the predominance of herbaceous species (Couto et al, 2017), which reflects the strong environmental filters, such as shallow soil, limited water and nutrient levels, and direct exposure to strong winds (Porembski, 2007;Couto et al, 2016). Low soil fertility influences the lower structure of the woody plant community and, consequently, both factors are responsible for the lower primary productivity, which is reflected in lower litter production in the ecosystems (Camara et al, 2018a(Camara et al, , 2018bMenezes et al, 2020;Câmara et al, 2021).…”

“…Nutrient cycling is an important soil entry route for nutrients derived from senescent plant material, and studies have focused on litterfall and its nutrient concentration in forest ecosystems, such as Ombrophilous Forest (Bianchin et al, 2017;Camara et al, 2018a;2018b), Semideciduous Forest (Scheer et al, 2011;Machado et al, 2018;Carvalho et al, 2019;Dick & Schumacher, 2020;Menezes et al, 2020;Câmara et al, 2021;Lagemann et al, 2022), and Deciduous Forest (Schumacher et al, 2018;Araújo et al, 2020). Regardless of the forest typology being subject to greater or lesser seasonality, climate conditions influence nutrient cycling (Scheer et al, 2011;Bianchin et al, 2017;Dick & Schumacher, 2020).…”