Impact of invasion by molasses grass (Melinis minutifloraP. Beauv.) on native species and on fires in areas of campo-cerrado in Brazil

Abstract

In the Cerrado Biome of Brazil, African grasses constitute a serious problem, occurring in virtually all protected areas. Molasses grass (Melinis minutiflora P. Beauv.) accumulates more biomass than do most other species of the herbaceous stratum vegetation native to the Cerrado. In this study, our aim was to determine the impact of M. minutiflora on native vegetation, as well as (using simulations of fire traits) on the characteristics of fires, in invaded areas of the Serra do Rola-Moça State Park (Parque Estadual da Serra do Rola-Moça, PESRM), a protected area where fires are frequent, in the state of Minas Gerais, Brazil. Our main results are that M. minutiflora considerably increases the amount of biomass, becoming the main combustible plant in the campo-cerrado (grassy-woody savanna) fires in the PESRM; that the native monocot biomass is inversely correlated with the M. minutiflora biomass, suggesting suppression of the native herbaceous stratum; that eudicots are diminished by M. minutiflora, both in number of individuals and number of species; and that fires are more severe in M. minutiflora-invaded areas.

Synergistic impacts of co‐occurring invasive grasses cause persistent effects in the soil‐plant system after selective removal

“…In contrast, the removal of M. minutiflora alone resulted in more considerable changes in plant community (Figure ) and soil properties (Figure ). Past research has demonstrated large effects of invasive M. minutiflora on biodiversity and ecosystem processes (Hoffmann & Haridasan, ; Klink, ; Martins et al, ; Martins, Leite, & Haridasan, ; Rossi et al, ; Yelenik & D’Antonio, ; Zenni et al, ). The species has been shown to decrease native species abundance and biomass, to exclude some biological groups, to increase fire frequency and intensity, and to increase soil fertility.…”

“…However, far fewer studies have evaluated the impacts of biological invasions (Lowry et al, ; Zenni, de Dechoum, & Ziller, ); most of them have assessed temperate and Mediterranean ecosystems (Stroud & Feeley, ), and there has been very little research into impacts in tropical ecosystems (Hulme et al, ; Zenni, Ziller, Pauchard, Rodriguez‐Cabal, & Nuñez, ). For example, in savanna ecosystems such as the Cerrado, we currently have some understanding of the community‐level impact of invasive grasses (Abreu, de Assis, Frison, Aguirre, & Durigan, ; Almeida‐Neto et al, ; Hoffmann & Haridasan, ; Rossi, Martins, Viana, Rodrigues, & Figueira, ), but we lack research into ecosystem‐level impacts.…”

“…Previous research has documented severe impacts of plant invasions, mainly African grasses, in different Cerrado formations (from grassland, savanna to forest formations). For instance, plant invasions in the Cerrado have caused local extinction of native species, homogenized habitats, altered fire regimes, hindered secondary succession and altered soil properties (Abreu et al, ; Almeida‐Neto et al, ; Cava, Pilon, Ribeiro, & Durigan, ; Gorgone‐Barbosa et al, ; Hoffmann & Haridasan, ; Martins et al, ; Rossi et al, ). However, none of these studies teased apart impacts of co‐occurring invasives or evaluated the ecological consequences of their removal.…”

Impact of invasive grasses on Cerrado under natural regeneration

“…and M. minutiflora have been described as very aggressive, and the most common invasive species in Cerrado (Pivello et al 1999b; Zenni and Ziller 2011; Ziller and Dechoum 2013; Sampaio and Schmidt 2014). Some authors had already shown negative impacts of these species on the invaded systems (Klink 1994;Pivello et al 1999a;Almeida-Neto et al 2010;Martins et al 2011;Rossi et al 2014). The presence of M. minutiflora, for example, inhibited the establishment of native tree species (Hoffmann and Haridasan 2008), hindering the recovery of degraded areas by increasing its abundance and excluding native species (Martins et al 2004).…”

Species composition, community and population dynamics of two gallery forests from the Brazilian Cerrado domain

“…Although the Brazilian Cerrado is a hotspot of biodiversity (Mendonça et al 2008, Myers et al 2000) and holds carbon stocks of nearly 300 Mg per hectare (Batlle-Bayer et al 2010, Paiva et al 2011), its species richness, diversity and biomass are still threatened by habitat loss, fragmentation, biological invasion and climate change (e.g., Lapola et al 2013, Jantz et al 2015, Rossi et al 2014). Within the Cerrado domain, gallery forests accompany the borders of rivers, creeks and streams, forming important corridors for wildlife among patches of remaining vegetation (Silveira et al 2014) that also protect aquatic ecosystems from substrate input, reducing water temperatures and erosion of river banks (Monteiro et al 2016, Londe and Silva 2014).…”