Changes in community composition and biomass inJuncus roemerianus scheele andSpartina bakeri merr. marshes one year after a fire

Abstract

Fires occur naturally in many wetlands and are widely used for marsh management. We examined the responses to fire ofJuncus roemerianus and Spartina bakeri marshes on Kennedy Space Center, Florida. In each marsh, we determined vegetation cover before burning on 5 permanent 15 m transects in the greater than 0.5 m and less than 0.5 m layers and sampled biomass on 25 plots (0.25 m2). One year after burning, we repeated the sampling.Species composition one year after burning was similar to that before the fire in both Juncus and Spartina marshes. Minor species tended to increase, but this was significant only in the less than 0.5 m layer. In mixed stands, f'tre appeared to favor Spartina bakeri. Total cover (sum of the cover values for each species) in both marshes reestablished by one year after burning. Biomass did not recover as rapidly. In the Juncus marsh one year after burning, live biomass was 47.2%, standing dead 18.7%, and total biomass 29.3% of that before burning.In the Spartina marsh, biomass one year after burning was live 42.3%, standing dead 21.4%, and total 30.7% of that before burning. Fire increased the ratio of live to dead biomass from 0.82 before burning to 1.85 one year ",ffter the fire in theJuncus marsh. In the Spartina marsh, the ratio of tire to dead biomass increased from 0.80 before burning to 1.59 one year after burning.

Cordgrass Biomass in Salt Marshes

“…Between "phalanx" growth species, S. bakeri accumulates ca. 400-700 g DW m -2 in the western Atlantic coast of North America (Chynoweth, 1975;Schmalzer et al, 1991). S. densiflora above-ground biomass accumulation changes markedly between different invaded marsh habitats in SW Iberian Peninsula.…”

“…In contrast, radial transects are applied when isolated clumps are easy to distinguish (Castellanos et al, 1994;Nieva et al, 2001a). The most frequent plot sizes are quadrants of 0.01 m2 (10 cm side) (Buchsbaum et al, 2009;Zhou et al, 2009a), 0.04 m 2 (20 cm side) (Castillo et al, 2008a;Culbertson et al, 2008;Buchsbaum et al, 2009;Charles & Dukes, 2009), 0.09 m 2 (30 cm side) (Holdredge et al, 2010) and 0.25 m 2 (50 cm side) (Schmalzer et al, 1991;Darby & Turner, 2008a,b;Krull & Craft, 2009;Wang et al, 2009;Zhou et al, 2009b) (Table 1). Larger plots normally show lower biomass values than smaller plots since they include both, areas with high and low shoot densities.…”

Diagnóstico ambiental das marismas no estuário da Lagoa dos Patos - RS

“…Figueroa et al (1988) e Nieva & Figueroa (1997) verificaram uma rápida produção de biomassa de S. densiflora após fogo, na Espanha, alcançando uma taxa média de recuperação de 64% ao ano, fazendo com que uma área queimada seja restabelecida em menos de 2 anos. Isacch et al (2004) verificaram a recuperação na estrutura da comunidade vegetal de J. acutus após 1 ano de um incêndio, similar ao relatado em marismas vegetadas por Juncus roemerianus nos EUA (Schmalzer et al 1991). Schmalzer et al (1991) e Hackney & De La Cruz (1981 estudando a ação do fogo sobre J. roemerianus nos EUA, verificaram que a recuperação da biomassa aérea ocorre em 3 anos após o incêndio.…”

The effect of fire on gas exchange and aboveground biomass production in annually vs biennially burnedSpartina pectinata wetlands

“…in Florida (Schmalzer et al 1991). This southeastern coastal species showed a similar increase in production after fire (Schmalzer et al 1991). Moreover, annual aboveground biomass production, estimated here as standing crop, in either annually or biennially burned S. pectinata wetlands is comparable with net primary production in eastern coastal congeners (Odum and Fanning 1973).…”