Decomposition of ground biomass of secondary forest and yield of annual crops in no tillage

ABSTRACT The objective of this work was to evaluate the dynamics of decomposition process of chopped secondary forest system, previously enriched with legumes Inga velutina Willd. and Stryphnodendron pulcherrimum (Willd.) Hochr. and the contribution of this process to the nutrient input to the cultivation of corn and bean under no-tillage. The experimental design was a randomized block, split plot with four replications. The plots were two species (I. velutina and S. pulcherrimum) and the subplots were seven times of evaluation (0, 7, 28, 63, 189, 252, 294 days after experiment installation). There was no difference (p ≥ 0.05) between the secondary forest systems enriched and no interaction with times for biomass waste, decomposition constant and half-life time. The waste of S. pulcherrimum trees had higher (p < 0.05) C/N ratio than that I. velutina. However, this one was higher (p < 0.05) in lignin content. Nevertheless, the dynamics of residue decomposition was similar. The corn yield was higher (p < 0.05) in cultivation under I.velutina waste. Meanwhile, the beans planted after corn, shows similar (p > 0.05) yield in both areas, regardless of the waste origin.

Biomass and abundance of termites in three remnant areas of Atlantic Forest in northeastern Brazil

Termite biomass and abundance were estimated in three remnant areas of Atlantic Forest in northeastern Brazil: Reserva Biológica de Pedra Talhada-RBPT (Alagoas State), Parque Estadual Dois Irmãos-PEDI (Pernambuco State), and Área de Proteção Ambiental Mata do Buraquinho-APMB (Paraíba State). A quantitative sampling of the termite assemblages present on trunks and leaf litter, in nests, and in the soil was undertaken during the months of June and July (rainy season) and November and December (dry season) of 2000. Thirty seven species of termites were encountered and quantified in the three remnant forest areas. The termite biomass varied from 10.09 to 11.30 g (fresh weight)/m² and abundance varied from 4911 to 5663 individuals/m². The subfamily Nasutitermitinae was dominant in terms of the number of species, biomass, and abundance. The soil-feeders were the most abundant at the three sites, while wood-feeders had the largest biomass at least at the PEDI and APMB sites. Among the microhabitats quantified, termites were most frequently encountered in the soil, being most heavily concentrated at depths of 0-20 cm. Two species stood out in terms of their biomass and abundance: Embiratermes parvirostris Constantino, on the soil, and Nasutitermes corniger (Motschulsky), on decomposing trunks and in nests. Estimates of biomass and abundance suggest that termites play an important role in the decomposition of the plant necromass in remnant forest areas of the Atlantic Forest in northeastern Brazil.

Bacteria diversity and microbial biomass in forest, pasture and fallow soils in the southwestern Amazon basin

It is well-known that Amazon tropical forest soils contain high microbial biodiversity. However, anthropogenic actions of slash and burn, mainly for pasture establishment, induce profound changes in the well-balanced biogeochemical cycles. After a few years the grass yield usually declines, the pasture is abandoned and is transformed into a secondary vegetation called "capoeira" or fallow. The aim of this study was to examine how the clearing of Amazon rainforest for pasture affects: (1) the diversity of the Bacteria domain evaluated by Polymerase Chain Reaction and Denaturing Gradient Gel Electrophoresis (PCR-DGGE), (2) microbial biomass and some soil chemical properties (pH, moisture, P, K, Ca, Mg, Al, H + Al, and BS), and (3) the influence of environmental variables on the genetic structure of bacterial community. In the pasture soil, total carbon (C) was between 30 to 42 % higher than in the fallow, and almost 47 % higher than in the forest soil over a year. The same pattern was observed for N. Microbial biomass in the pasture was about 38 and 26 % higher than at fallow and forest sites, respectively, in the rainy season. DGGE profiling revealed a lower number of bands per area in the dry season, but differences in the structure of bacterial communities among sites were better defined than in the wet season. The bacterial DNA fingerprints in the forest were stronger related to Al content and the Cmic:Ctot and Nmic:Ntot ratios. For pasture and fallow sites, the structure of the Bacteria domain was more associated with pH, sum of bases, moisture, total C and N and the microbial biomass. In general microbial biomass in the soils was influenced by total C and N, which were associated with the Bacteria domain, since the bacterial community is a component and active fraction of the microbial biomass. Results show that the genetic composition of bacterial communities in Amazonian soils changed along the sequence forest-pasture-fallow.

EFFECT OF WATER AVAILABILITY ON SOIL MICROBIAL BIOMASS IN SECONDARY FOREST IN EASTERN AMAZONIA

Soil microbial biomass (SMB) plays an important role in nutrient cycling in agroecosystems, and is limited by several factors, such as soil water availability. This study assessed the effects of soil water availability on microbial biomass and its variation over time in the Latossolo Amarelo concrecionário of a secondary forest in eastern Amazonia. The fumigation-extraction method was used to estimate the soil microbial biomass carbon and nitrogen content (SMBC and SMBN). An adaptation of the fumigation-incubation method was used to determine basal respiration (CO2-SMB). The metabolic quotient (qCO2) and ratio of microbial carbon:organic carbon (CMIC:CORG) were calculated based on those results. Soil moisture was generally significantly lower during the dry season and in the control plots. Irrigation raised soil moisture to levels close to those observed during the rainy season, but had no significant effect on SMB. The variables did not vary on a seasonal basis, except for the microbial C/N ratio that suggested the occurrence of seasonal shifts in the structure of the microbial community.

Utilisation of biomass for energy production in the North-West Russian forest industry

Traditionally, fossil fuels have always been the major sources of the modern energy production. However prices on these energy sources have been constantly increasing. The utilization of local biomass resources for energy production can substitute significant part of the required energy demand in different energy sectors. The introduction of the biomass usage can easily be started in the forest industry first as it possesses biomass in a large volume. The forest industry energy sector has the highest potential for the fast bioenergy development in the North-West Russia. Therefore, the question concerning rational and effective forest resources use is important today as well as the utilization of the forestry by-products. This work describes and analyzes the opportunities of utilising biomass, mainly, in the form of the wood by-products, for energy production processes in general, as well as for the northwest Russian forest industry conditions. The study also covers basic forest industry processes and technologies, so, the reader can get familiar with the information about the specific character of the biomass utilization. The work gives a comprehensive view on the northwest forest industry situation from the biomass utilisation point of view. By presenting existing large-scale sawmills and pulp and paper mills the work provides information for the evaluation of the future development of CHP investments in the northwest Russian forest industry.

Phenology, litterfall, growth, and root biomass in a tidal floodplain forest in the Amazon estuary

The dynamics of forests subject to inundation appears to be strongly influenced by the frequency and intensity of natural disturbances such as flooding. In a late successional tidal floodplain forest near the Amazon port of Belém, Brazil, we tested this prediction by measuring seasonal patterns of phenology and litterfall in relation to two key variables: rainfall and tide levels. In addition, we estimated the root biomass and the annual growth of the forest community by measuring stem increments over time. Our results showed high correlations between phenological events (flowering and fruiting) and rainfall and tide levels, while correlations between litterfall and these variations were generally weaker. Contrary to our prediction, root biomass to 1 m depth showed no significant differences along the topographic gradient, and the root biomass at all topographic levels was low to intermediate compared with other neotropical forests. Both litterfall and total stem increment were high compared to other tropical forest, indicating the high productivity of this ecosystem.

Elevated CO2 enrichment induces a differential biomass response in a mixed species temperate forest plantation

• In a free-air CO2 enrichment study (BangorFACE) Alnus glutinosa, Betula pendula and Fagus sylvatica were planted in areas of one, two and three species mixtures (n=4). The trees were exposed to ambient or elevated CO2 (580 µmol mol-1) for four years, and aboveground growth characteristics measured. • In monoculture, the mean effect of CO2 enrichment on aboveground woody biomass was +29, +22 and +16% for A. glutinosa, F. sylvatica, and B. pendula respectively. When the same species were grown in polyculture, the response to CO2 switched to +10, +7 and 0%, for A. glutinosa, B. pendula, and F. sylvatica respectively. • In ambient atmosphere our species grown in polyculture increased aboveground woody biomass from 12.9 ± 1.4 kg m-2 to 18.9 ± 1.0 kg m-2, whereas in an elevated CO2 atmosphere aboveground woody biomass increased from 15.2 ± 0.6 kg m-2 to 20.2 ± 0.6 kg m-2. The overyielding effect of polyculture was smaller (+7%) in elevated CO2 than in an ambient atmosphere (+18%). • Our results show that the aboveground response to elevated CO2 is significantly affected by intra- and inter-specific competition, and that elevated CO2 response may be reduced in forest communities comprised of tree species with contrasting functional traits.

Determination of anthropogenic and biogenic compounds on atmospheric aerosol collected in urban, biomass burning and forest areas in Sao Paulo, Brazil

This study was conducted at three sites of different characteristics in Sao Paulo State Sao Paulo (SPA), Piracicaba (PRB) and Mate Atlantica Forest (MAT) PM(10), n-alkanes. pristane and phytane, PAHs, water-soluble ions and biomass burning tracers like levoglucosan and retene, were determined in quartz fiber filters. Samplings occurred on May 8th to August 8th, 2007 at the MAT site; on August 15th to 29th in 2007 and November 10th to 29th in 2008 at the PRB site and, March 13th to April 4th in 2007 and August 7th to 29th in 2008 at the SPA site Aliphatic compounds emitted biogenically were less abundant at the urban sites than at the forest site, and its distribution showed the influence of tropical vascular plants Air mass transport front biomass burning regions is likely to impact the sites with specific molecular markers The concentrations of all species were variable and dependent of seasonal changes In the most dry and polluted seasons, n-alkane and canon total concentrations were similar between the megacity and the biomass burning site PAHs and inorganic ion abundances were higher at Sao Paulo than Piracicaba, yet, the site influenced by biomass burning seems lobe the most impacted by the organic anion abundance in the atmosphere Pristane and phytane confirm the contamination by petroleum residues at urban sites, at the MAT site, biological activity and long range transport of pollutants might influence the levels of pristane (C) 2010 Elsevier B V All rights reserved

Forest natural regeneration and biomass production after slash and burn in a seasonally dry forest in the Southern Brazilian Amazon

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Biomass consumption and CO2, CO and main hydrocarbon gas emissions in an Amazonian forest clearing fire

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Variation in liana abundance and biomass along an elevational gradient in the tropical Atlantic Forest (Brazil)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Size, taxonomic and biomass distributions of flying insects in Central Amazonia: Forest edge vs. understory

Significantly more individuals and biomass of flying insects were present at the forest edge than in the understory throughout the year, as monitored by flight interception traps, in Central Amazonia. Numbers and biomass of flying insects increased at higher rates at the edge with rainfall, associated with termite swarming behavior and increased Homopteran density. The most abundant insects were Diptera, Coleoptera, Hymenoptera and Isoptera, whose ranked abundances varied with respect to forest edge and understory, as well as with season.

Soil and biomass mercury emissions during a prescribed fire in the Amazonian rain forest

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)