Post-Disturbance Aboveground Biomass Accumulation in Global Secondary Forests

Abstract

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Applying biomass and stem fluxes to quantify temporal and spatial fluctuations of an old-growth forest in disturbance

“…The old-growth forest had stable stem recruitment and biomass growth. Results of stem fluxes were consistent with other previous observations (Sheil and May, 1996;Johnson et al, 2000;Davies, 2001). Disturbances such as drought, hurricanes, insect outbreaks or wind (Beard et al, 2005;Mascaro et al, 2005), and physical conditions such as temperature, light and topography, are the two primary factors, which affect the temporal fluctuation of pools (Miura and Yamamoto, 2003;Lewis et al, 2004;Phillips et al, 2004).…”

Evidence for a recent increase in forest growth

“…A steady lengthening of the growing season has been documented worldwide (7), and even a shift in the seasonal phase of surface temperatures has been detected (28). Growing degree days correlate with the speed of forest recovery from pasture in the Amazon (9,29) and increased plant growth in boreal forests (11,25). Fig.…”

“…Across forest types, the period of recovery consists of a rapid rise in above-ground biomass (AGB) followed by a leveling off as the canopy fills in and biomass shifts from the sum of many small stems to fewer, larger canopy trees. The rate and asymptote of this pattern of biomass recovery can differ across stands because of nutrient availability and species composition or can differ between regions because of climate and disturbance regimens; however, the functional form of this response remains similar across forest types and regions (9,10).…”

Integration of remotely sensed and ancillary data to assess the impacts of shifting cultivation / Integração de dados de detecção remota com dados complementares para a avaliação dos impates da agricultura de corte e queima

“…1) was estimated based on the equations developed by Zarin et al (2001). These authors used the data from Johnson et al (2000), which compiled global data on the aboveground biomass accumulation in secondary forests. Zarin et al (2001) developed global equations (for different soil texture: sandy and non-sandy) and tested their regional applicability with validation data from the Amazon, not included in the global data set from which equations were derived:…”

“…The product FP×T×L/365 is an index that represents the increase in metabolic processes commonly associated with increased temperature in the presence of adequate moisture ( JOHNSON et al, 2000).…”