Growth and establishment of monodominant stands affected by ENSO and flooding in the Pantanal

Abstract

Climatic factors can influence the establishment and growth of wood species, but little is known about the effect of these factors on monodominant communities in wetlands. Therefore, we asked how climatic factors, such as ENSO (El Niño-Southern Oscillation), precipitation and flooding, influence growth and establishment of the dominant species Erythrina fusca in the Pantanal. We determined the age of sampled individuals, the age of the population and evaluated the effects of climate on tree growth. We obtained samples for dendrochronological analyses using destructive (seven individuals) and non-destructive methods. We cross-dated and built a chronology, correlating results with climatic factors. We sampled 0.6 ha of the population and separated individuals into diameter classes to determine age based on diameter/age ratio obtained through dendrochronological analyses. We obtained a chronology with individuals up to 34 years old, while in the population sample, the oldest individual was 54 years old. The factors that influenced growth during the study period were precipitation (positive correlation) and El Niño (negative correlation). E. fusca individuals seem to grow more during the period of highest precipitation, and El Niño events reduce precipitation in the Pantanal, resulting in a decrease in the growth of E. fusca individuals. We detected a decrease of young individuals in the last nine years, which seems to be related to the decrease in minimum flood levels. This indicates a future decline in the number of individuals. These results allow us to propose measures to protect these monodominant formations, which mainly involve avoiding further anthropic activities, that could reduce flooding levels.

Linking regeneration niche to monodominance in biodiverse tropical forest landscapes

“…Although most previous studies highlighted the importance of local factors, such as fire, soil water‐holding capacity, herbivory and ectomycorrhizal associations, on monodominance patterns (Arieira & Cunha, 2006; S. P. Ribeiro & Brown, 2006; Steenbock et al, 2011; Ibanez & Birnbaum, 2014; Kazmierczak et al, 2016; Marimon et al, 2016; Ebenye et al, 2017; Sansevero et al, 2017; Pivello et al, 2018; Steege et al, 2019), our results underscore the importance of taking into account factors that limit species dominance, particularly temperature, over a broad geographical scale. Recently, Tovar et al (2019) and Gris et al (2020) pointed out the importance of precipitation for the maintenance of monodominant forests. Previously, Leathwick and Austin (2001) also demonstrated the influence of mean annual temperature on single‐species Nothofagus dominance in New Zealand forests.…”

“…Nevertheless, particularly at a regional scale (e.g., biomes; sensu Bailey, 1996), few studies have devoted attention to how abiotic factors could influence the occurrence of monodominant forest patches (Tovar et al, 2019;Gris et al, 2020).…”

“…In sites affected by fire and deforestation, species with functional traits such as the massive production of small seeds, rapid growth in open environments and fire resistance could form large monodominant forest patches in tropical forest regions (Ibanez & Birnbaum, 2014; Arroyo‐Rodríguez et al, 2017; Pivello et al, 2018). Nevertheless, particularly at a regional scale (e.g., biomes; sensu Bailey, 1996), few studies have devoted attention to how abiotic factors could influence the occurrence of monodominant forest patches (Tovar et al, 2019; Gris et al, 2020).…”

Morphological-anatomical and chemical features of Copernicia alba fruits and seeds, a palm from Brazilian Pantanal

“…Copernicia alba is one of these palms, native to South America, and is found in Brazil, northern Argentina, Paraguay, and southern Bolivia [5][6][7]. In Brazil, this species is regionally known as carandá and is widely distributed in wetlands, in large monodominant formations along the Paraguay River known as carandazais [8]. The estimated carandá area in the Pantanal vegetation is 2.3%, the second most representative monotypic formation [9].…”