Early recruitment responses to interactions between frequent fires, nutrients, and herbivory in the southern Amazon

14 de fevereiro de 2015

fev 14, 2015

Tara Joy Massad, Jennifer K. Balch, Cândida Lahís Mews, Pábio Porto, Ben Hur Marimon Junior, Raimundo Mota Quintino, Paulo M. Brando, Simone A. Vieira, Susan E. Trumbore

Understanding tropical forest diversity is a long-standing challenge in ecology. With global change, it has become increasingly important to understand how anthropogenic and natural factors interact to determine diversity.

Anthropogenic increases in fire frequency are among the global change variables affecting forest diversity and functioning, and seasonally dry forest of the southern Amazon is among the ecosystems most affected by such pressures. Studying how fire will impact forests in this region is therefore important for understanding ecosystem functioning and for designing effective conservation action.

We report the results of an experiment in which we manipulated fire, nutrient availability, and herbivory. We measured the effects of these interacting factors on the regenerative capacity of the ecotone between humid Amazon forest and Brazilian savanna. Regeneration density, diversity, and community composition were severely altered by fire. Additions of P and N + P reduced losses of density and richness in the first year post-fire. Herbivory was most important just after germination.

Diversity was positively correlated with herbivory in unburned forest, likely because fire reduced the number of reproductive individuals. This contrasts with earlier results from the same study system in which herbivory was related to increased diversity after fire. We documented a significant effect of fire frequency; diversity in triennially burned forest was more similar to that in unburned than in annually burned forest, and the community composition of triennially burned forest was intermediate between unburned and annually burned areas. Preventing frequent fires will therefore help reduce losses in diversity in the southern Amazon’s matrix of human-altered landscapes.

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Indigenous Peoples and the Reducing Emissions from Deforestation and Forest Degradation (REDD+) mechanism in the Brazilian Amazon – Subsidies to the Discussion of Benefits Sharing

Indigenous Peoples and the Reducing Emissions from Deforestation and Forest Degradation (REDD+) mechanism in the Brazilian Amazon – Subsidies to the Discussion of Benefits Sharing

The purpose of this publication is to provide a better understanding on the contribution of indigenous perspectives to the discussion of REDD+ benefit sharing, based on some indig- enous’ points of view and experiences of the Amazon indigenous peoples in Brazil. More specifically, the aim from a participatory and consultative process is to provide support for the construction benefit sharing models for REDD+ programs, which actually promotes inclu- sion of these people, focusing on the Brazilian context.