Impact of invasive grasses on Cerrado under natural regeneration

Damasceno, Gabriella; Souza, Lara; Pivello, Vânia Regina; Gorgone‐Barbosa, Elizabeth; Giroldo, Paula Z.; Fidelis, Alessandra

doi:10.1007/s10530-018-1800-6

Cited by 55 publications

(35 citation statements)

References 59 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Non‐native grass invasion can represent a huge threat to tropical grasslands, due to the negative impact caused by exotic grasses on native grasses and forbs (e.g. Pivello, Shida & Meirelles, ; Damasceno et al ., in press; Dresseno et al ., in press). In addition to suppressing native species, invasive grasses can lead to a high biomass accumulation, with consequences for fire regimes, including increased fire intensity (Mistry & Berardi, ; Setterfield et al ., ; Gorgone‐Barbosa et al ., ).…”

Section: Resiliencementioning

confidence: 99%

Resilience and restoration of tropical and subtropical grasslands, savannas, and grassy woodlands

et al. 2018

Self Cite

View full text Add to dashboard Cite

Despite growing recognition of the conservation values of grassy biomes, our understanding of how to maintain and restore biodiverse tropical grasslands (including savannas and open‐canopy grassy woodlands) remains limited. To incorporate grasslands into large‐scale restoration efforts, we synthesised existing ecological knowledge of tropical grassland resilience and approaches to plant community restoration. Tropical grassland plant communities are resilient to, and often dependent on, the endogenous disturbances with which they evolved – frequent fires and native megafaunal herbivory. In stark contrast, tropical grasslands are extremely vulnerable to human‐caused exogenous disturbances, particularly those that alter soils and destroy belowground biomass (e.g. tillage agriculture, surface mining); tropical grassland restoration after severe soil disturbances is expensive and rarely achieves management targets. Where grasslands have been degraded by altered disturbance regimes (e.g. fire exclusion), exotic plant invasions, or afforestation, restoration efforts can recreate vegetation structure (i.e. historical tree density and herbaceous ground cover), but species‐diverse plant communities, including endemic species, are slow to recover. Complicating plant‐community restoration efforts, many tropical grassland species, particularly those that invest in underground storage organs, are difficult to propagate and re‐establish. To guide restoration decisions, we draw on the old‐growth grassland concept, the novel ecosystem concept, and theory regarding tree cover along resource gradients in savannas to propose a conceptual framework that classifies tropical grasslands into three broad ecosystem states. These states are: (1) old‐growth grasslands (i.e. ancient, biodiverse grassy ecosystems), where management should focus on the maintenance of disturbance regimes; (2) hybrid grasslands, where restoration should emphasise a return towards the old‐growth state; and (3) novel ecosystems, where the magnitude of environmental change (i.e. a shift to an alternative ecosystem state) or the socioecological context preclude a return to historical conditions.

show abstract

Section: Resiliencementioning

confidence: 99%

Resilience and restoration of tropical and subtropical grasslands, savannas, and grassy woodlands

et al. 2018

Self Cite

View full text Add to dashboard Cite

show abstract

“…The accumulated biomass was two-fold higher in areas without fire for seven years and three-fold higher in areas without fire for 12 years (Zanzarini, unpublished data). The amount of dead biomass tends to increase with a longer fire return interval [41] and with an abundance of invasive grasses, which produce much biomass and significantly increase the fuel load [44], leading to more intense fires [45]. Therefore, we believe that the high amount of accumulated fuel due to the zero-fire policy in the RNST was the main reason for the megafires.…”

Section: The "Zero-fire" Policy In the Cerrado And Its Consequencesmentioning

confidence: 99%

The Year 2017: Megafires and Management in the Cerrado

Fidelis

Alvarado

Barradas

et al. 2018

Fire

Self Cite

View full text Add to dashboard Cite

The year 2017 was a megafire year, when huge areas burned on different continents. In Brazil, a great extension of the Cerrado burned, raising once more the discussion about the “zero-fire” policy. Indeed, most protected areas of the Cerrado adopted a policy of fire exclusion and prevention, leading to periodic megafire events. Last year, 78% of the Chapada dos Veadeiros National Park burned at the end of the dry season, attracting media attention. Furthermore, 85% of the Reserva Natural Serra do Tombador burned as a result of a large accumulation of fuel caused by the zero-fire policy. In 2014, some protected areas started to implement the Integrate Fire Management (IFM) strategy. During 2017, in contrast to other protected areas, the Estação Ecológica Serra Geral do Tocantins experienced no megafire events, suggesting that a few years of IFM implementation led to changes in its fire regime. Therefore, we intended here to compare the total burned area and number of fire scars between the protected areas where IFM was implemented and those where fire exclusion is the adopted policy. The use of fire as a management tool aimed at wildfire prevention and biodiversity preservation should be reconsidered by local managers and environmental authorities for most Cerrado protected areas, especially those where open savanna physiognomies prevail. Changing the paradigm is a hard task, but last year’s events showed the zero-fire policy would bring more damage than benefits to Cerrado protected areas.

show abstract

“…In addition to the native species, C 4 African grasses (such as Urochloa spp., previously Brachiaria) were introduced in Brazil for cattle forage (Pivello et al 1999a;Durigan et al 2007;Ziller & Dechoum 2013). Such African grasses have spread from the pastures and became a threaten to Cerrado native herbs by reducing their biomass and diversity (Pivello et al 1999a;Damasceno et al 2018).…”

Section: Introductionmentioning

confidence: 99%

Fire cues and germination of invasive and native grasses in the Cerrado

et al. 2020

Self Cite

View full text Add to dashboard Cite

Fire-related cues may enhance seed recruitment in flammable ecosystems and differences in fire-germination responses of invasive vs. native species can drive the invasion process. We evaluated the effects of heat shock and smoke water solution treatment on seed germination of invasive (Melinis minutiflora, Urochloa decumbens, U. brizantha) and native grasses (Axonopus pressus, Aristida setifolia, Gymnopogon foliosus) of the Cerrado. The effect of fire temperature was tested by exposing seeds to heat shock treatments of 60, 100, and 200 °C for one minute, comparing them to untreated seeds. The effect of smoke was tested by soaking seeds for 24-h in an aqueous smoke comparing them to seeds soaked in distilled water. Differences among treatments were evaluated by ANOVA and randomization tests. None of the tested species had germination stimulated by the temperature or smoke. Both species of Urochloa experienced decreased viability with increasing temperature, while seeds of native species and M. minutiflora tolerated heat shock up to 200 °C. The invasive grasses usually germinated faster than the native grasses. Germination time is therefore a crucial trait driving the invasion process, irrespective of fire-related cues. Other seed traits (e.g. dormancy) and higher resprouting capacity may help invasive species to persist in frequently burned savannas.

show abstract

Impact of invasive grasses on Cerrado under natural regeneration

Cited by 55 publications

References 59 publications

Resilience and restoration of tropical and subtropical grasslands, savannas, and grassy woodlands

Resilience and restoration of tropical and subtropical grasslands, savannas, and grassy woodlands

The Year 2017: Megafires and Management in the Cerrado

Fire cues and germination of invasive and native grasses in the Cerrado

Contact Info

Product

Resources

About