Enzymatic Activity Measured By Microcalorimetry In Soil Amended With Organic Residues [atividade Enzimática Avaliada Por Microcalorimetria Em Solo Tratado Com Diferentes Resíduos Orgânicos]

Enzymatic activity is an important property for soil quality evaluation. Two sequences of experiments were carried out in order to evaluate the enzymatic activity in a soil (Rhodic Eutrudox) amended with cattle manure, earthworm casts, or sewage sludges from the municipalities of Barueri and Franca. The activity of commercial enzymes was measured by microcalorimetry in the same soil samples after sterilization. In the first experiment, the enzyme activities of cellulase, protease, and urease were determined in the soil samples during a three month period. In the second sequence of experiments, the thermal effect of the commercial enzymes cellulase, protease, and urease on sterilized soil samples under the same tretaments was monitored for a period of 46 days. The experimental design was randomized and arranged as factorial scheme in five treatments x seven samplings with five replications. The treatment effects were statistically evaluated by one-way analysis of variance. Tukey ́s test was used to compare means at p ≤ 0.05. The presence of different sources of organic residues increased the enzymatic activity in the sampling period. Cattle manure induced the highest enzymatic activity, followed by municipal sewage sludge, whereas earthworm casts induced the lowest activity, but differed from control treatment. The thermal effect on the enzyme activity of commercial cellulase, protease, and urease showed a variety of time peaks. These values probably oscillated due to soil physical-chemical factors affecting the enzyme activity on the residues.35411671175Albiach, R., Canet, R., Pomares, F., Ingelmo, F., Microbial biomass content and enzymatic activities after the application of organic amendments to a horticultural soil (2000) Biores. Technol., 75, pp. 43-48Barros, N., Feijóo, S., A combined mass and energy balance to provide bioindicators of soil microbiological quality (2003) Biophys. Chem., 104, pp. 561-572Benitez, E., Sainz, H., Nogales, R., Hydrolytic enzyme activities of extracted humic substances during the vermicomposting of a lignocellulosic olive waste (2005) Biores. Technol., 96, pp. 785-790Caldwell, B.A., Enzyme activities as a component of soil biodiversity: A review (2005) Pedobiology, 49, pp. 637-644. , In: INTERNATIONAL SYMPOSIUM ON IMPACTS OF SOIL BIODIVERSITY ON BIOGEOCHEMICAL PROCESSES IN ECOSYSTEMS, 2004, Taipei, TaiwanCarter, M.R., Organic matter and sustainability (2001) Sustainable management of soil organic matter, pp. 9-22. , In: REES, B.C.BALL, B.C.CAMPBELL, C.D. & WATSON, C.A., eds, Wallingford, CAB InternationalCenciani, K., Freitas, S.S., Critter, S.A.M., Airoldi, C., Microbial enzymatic activity and thermal effect in a tropical soil treated with organic materials (2008) Sci. Agric., 65, pp. 674-680Critter, S.A.M., Freitas, S.S., Airoldi, C., Calorimetry versus respirometry for the monitoring of microbial activity in a tropical soil (2001) Appl. Soil Ecol, 18, pp. 217-227Critter, S.A.M., Freitas, S.S., Airoldi, C., Microbial biomass and microcalorimetric methods in tropical soils (2002) Thermochim. Acta, 394, pp. 145-154Critter, S.A.M., Freitas, S.S., Airoldi, C., Comparison of microbial activity in some Brazilian soils by microcalorimetric and respirometric methods (2004) Thermochim. Acta, 410, pp. 35-46Critter, S.A.M., Freitas, S.S., Airoldi, C., Microcalorimetric measurements of the metabolic activity by bacteria and fungi in some Brazilian soils amended with different organic matter (2004) Thermochim. Acta, 417, pp. 275-281Dick, R.P., Kandeler, E., Enzymes in soils (2004) Encyclopedia of soils in the environment, pp. 448-455. , In: HILLEL, D., ed, Oxford, ElsevierDilly, O., Nannipieri, P., Response of ATP content, respiration rate and enzyme activities in an arable and a forest soil to nutrient additions (2001) Biol. Fert. Soils, 34, pp. 34-64Dinesh, R., Suryanarayana, M.A., Chaudhuri, S.G., Sheeja, T.E., Long-term of leguminous cover crops on the biochemical properties of a sandy clay loam Fluventic Sulfaquent in a humid tropical region of India (2004) Soil Tillage Res., 77, pp. 69-77Gattinger, A., Höfle, M.G., Schloter, M., Embacher, A., Böhme, F., Munch, J.C., Labrenz, M., Traditional cattle manure application determines abundance, diversity and activity of methanogenic Archaea in arable European soil (2007) Environ. Microbiol., 9, pp. 612-624Hope, C.F.A., Burns, R.G., Activity, origins and location of cellulase in a silt loam soil (1987) Biol. Fert. Soils, 5, pp. 164-170Kandeler, E., Tscherko, D., Bruce, K.D., Stemmer, M., Hobbs, P.J., Bardgett, R.D., Amelung, W., Structure and function of the soil microbial community in microhabitats of a heavy metal polluted soil (2000) Biol. Fert. Soils, 32, pp. 390-400Kunito, T., Saeki, K., Shigeko Goto, S., Hayashi, H., Oyaizu, H., Matsumoto, S., Copper and zinc fractions affecting microorganisms in long-term sludge amended soils (2001) Biores. Technol., 79, pp. 135-146Ladd, J.N., Butler, J.H.A., Short-term assays of soil proteolytic enzyme activities using proteins and dipeptide derivatives as substrates (1972) Soil Biol. Biochem., 4, pp. 19-30Laor, Y., Raviv, M., Borisover, M., Evaluating microbial activity in composts using microcalorimetry (2004) Termochim. Acta., 420, pp. 119-125Marinari, S., Masciandaro, G., Ceccanti, B., Grego, S., Influence of organic and mineral fertilizers on soil biological and physical properties (2000) Biores. Technol., 72, pp. 9-17Marzadori, C., Francioso, O., Ciavatta, C., Gessa, C., Activity and stability of jack bean urease in the presence of peat humic acids obtained using different extractants (2000) Biol. Fert. Soils, 32, pp. 415-420Núñez-Regueira, L., Núñez-Fernandez, O., Rodriguez Añón, J.A., Castiñeiras, J.P., The influence of some physicochemical parameters on the microbial growth in soils (2002) Termochim. Acta, 394, pp. 1232-2131Pascual, J.A., Moreno, J.L., Hernández, T., García, C., Persistence of immobilised and total urease and phosphatase activities in a soil amended with organic wastes (2002) Biores. Technol., 82, pp. 73-78Prado, A.G.S., Airoldi, C., Effect of the pesticide 2,4-D on microbial activity of the soil monitored by microcalorimetry (2000) Thermochim. Acta, 349, pp. 17-22Schloter, M., Dilly, O., Munch, J.C., Indicators for evaluating soil quality (2003) Agric. Ecosyst. Environ., 98, pp. 255-262Shukla, M.K., Lal, R., Ebinger, M., Determining soil quality indicators by factor analysis (2006) Soil Tillage Res., 87, pp. 194-204(1996) Keys to soil taxonomy, p. 644. , SOIL SURVEY STAFF, 7. ed. Washington, DC, U.S. Department of AgricultureTabatabai, M.A., Bremner, J.M., Assay of urease activity in soil (1972) Soil Biol. Biochem., 4, pp. 479-48

Enzymatic activity measured by microcalorimetry in soil amended with organic residues

Enzymatic activity is an important property for soil quality evaluation. Two sequences of experiments were carried out in order to evaluate the enzymatic activity in a soil (Rhodic Eutrudox) amended with cattle manure, earthworm casts, or sewage sludges from the municipalities of Barueri and Franca. The activity of commercial enzymes was measured by microcalorimetry in the same soil samples after sterilization. In the first experiment, the enzyme activities of cellulase, protease, and urease were determined in the soil samples during a three month period. In the second sequence of experiments, the thermal effect of the commercial enzymes cellulase, protease, and urease on sterilized soil samples under the same tretaments was monitored for a period of 46 days. The experimental design was randomized and arranged as factorial scheme in five treatments x seven samplings with five replications. The treatment effects were statistically evaluated by one-way analysis of variance. Tukey´s test was used to compare means at p < 0.05. The presence of different sources of organic residues increased the enzymatic activity in the sampling period. Cattle manure induced the highest enzymatic activity, followed by municipal sewage sludge, whereas earthworm casts induced the lowest activity, but differed from control treatment. The thermal effect on the enzyme activity of commercial cellulase, protease, and urease showed a variety of time peaks. These values probably oscillated due to soil physical-chemical factors affecting the enzyme activity on the residues

Bacteria diversity and microbial biomass in forest, pasture and fallow soils in the southwestern Amazon basin Diversidade de bacteria e biomassa microbiana em solos sob floresta, pastagem e capoeira no sudoeste da Amazônia

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.<br>Os solos da floresta tropical amazônica supostamente abrigam elevada biodiversidade microbiana. Entretanto, as ações antrópicas de corte e queima, especialmente para o estabelecimento de pastagens, induzem mudanças profundas nos ciclos biogeoquímicos. Após alguns anos de uso, a produtividade da gramínea declina, a pastagem é abandonada, tornando-se uma vegetação secundária, denominada "capoeira" ou pousio. O objetivo deste trabalho foi avaliar como o desmatamento da floresta amazônica para o estabelecimento de pastagem altera: a diversidade do domínio Bacteria avaliada por PCR-DGGE; a biomassa microbiana e alguns atributos químicos do solo (pH, umidade, P, K, Ca, Mg, Al, H + Al e SB); e a influência de variáveis ambientais na estrutura genética de comunidades bacterianas. A pastagem continha entre 30 e 42 % mais carbono total (C) do que a capoeira e aproximadamente 47 % mais C do que a floresta ao longo do ano. O mesmo padrão foi observado para o nitrogênio total (N). A biomassa microbiana na pastagem foi 38 e 26 % maior do que nas áreas de capoeira e floresta, respectivamente, durante a estação chuvosa. O padrão de bandas em DGGE revelou menor número de bandas por área na estação seca, porém as diferenças na estrutura de comunidades bacterianas entre as áreas de estudo foram mais bem definidas do que na estação chuvosa. O perfil de bandas encontrado na floresta esteve mais associado ao teor de Al e às taxas Cmic:Ctot e Nmic:Ntot. Em relação às áreas de pastagem e capoeira, a estrutura do domínio Bacteria esteve mais associada a pH, soma de bases, umidade, C e N totais e à biomassa microbiana. De modo geral, a biomassa microbiana em solos é influenciada pelos teores de C e N totais, os quais estiveram associados ao domínio Bacteria, visto que a comunidade bacteriana é uma fração componente e ativa da biomassa microbiana. Os resultados indicam que a composição genética das comunidades microbianas dos solos da Amazônia mudou ao longo da sequência floresta-pastagem-capoeira