Soil microbial attributes in rangelands with diferents grazing intensities

  • J. K. Fedrigo Programa de Pós-graduação em Zootecnia. Faculdade de Agronomia, Universidade Federal do Rio Grande do Sul.
  • P. F. Ataide Programa de Pós-graduação em Zootecnia. Faculdade de Agronomia, Universidade Federal do Rio Grande do Sul.
  • J. C. R. Azambuja Filho Programa de Pós-graduação em Zootecnia. Faculdade de Agronomia, Universidade Federal do Rio Grande do Sul.
  • C. Nabinger Programa de Pós-graduação em Zootecnia. Faculdade de Agronomia, Universidade Federal do Rio Grande do Sul.
  • M. A. Barbosa Programa de Pós-graduação em Zootecnia. Faculdade de Agronomia, Universidade Federal do Rio Grande do Sul.
  • I. Anghinoni Programa de Pós-graduação em Ciência do Solo, UFRGS.

Keywords:

Soil organic matter, microbial biomass, microbial respiration, CO2 emission

Abstract

The soil microbial biomass is the living fraction of organic matter, being responsible for several biological and biochemical processes of the soil and influenced by the conditions imposed by the environment. To evaluate the effect of grazing on changes in soil microbial attributes we studied four grazing intensities based on natural grassland of Pampa Biome: 4, 8, 12 and 16 kg of dry matter per day per 100 kg of animal live weight, compared to an area without grazing. We used randomized block design with two replications. Samples were taken on 11/23/2011 and analyzed to determine the levels of soil organic matter (SOM), microbial biomass, nitrogen, respiration and metabolic quotient. The results showed that at intermediate grazing intensities, such as 12%, minor disturbances occur in soil microbial biomass compared to other intensities, emit less CO2 into the atmosphere for each animal unit produced. The levels of organic matter and soil microbial biomass systems are lower in grazed than in areas excluded from grazing for a long period.

Downloads

Download data is not yet available.

References

Alef K. & P. Nannipieri. 1995. Methods in applied soil microbiology and brochemistry. London: Academic Press.

Anderson J.P.E. & K.H.Domsh. 1993. The metabolic quocient (qCO2) as a specific activity parameter to assess the effects of environment conditions, such as pH, on te microbial biomass of forest soils. Soil Biol. Biochem. 25: 393- 395.

Bardegett R.D., D.A. Wardle & G.W. Yeates. 1998. Linking aboveground and belowground food webs: how plant responses to foliar herbivory influence soil organisms. Soil Biol. Biochem. 30: 1867-1867.

Bertol I., K.E. Gomes, R.B.N. Denardin, L.A.Z. Machado & G.E. Maraschin. 1998. Propriedades físicas do solo relacionadas a diferentes níveis de oferta de forragem numa pastagem natural. Rev. Bras. Zootec. 33:779-786.

Blair N., R.D. Faulkner,A.R. Till & G.J. Crocker. 2006. Long-term management impacts on soil C, N and physical fertility. Part III: Tamworth crop rotation experiment. Soil Till. Res. 91: 48-56.

Brookes P.C., A. Landman, G. Pruden, D.S. Jenkinson. 1985. Chloroform fumigation and the release of soil nitrogen: a rapid direct extraction method to measure microbial biomass nitrogen in the soil. Soil Biol. Biochem. 17: 837-842.

Camargo O.C. 1983. Compactação do solo e densidade de plantas. Fundação CARGILL.Campinas,BR. pp. 45.

Cattelan A. J. & C. Vidor 1990. Sistemas de cultura e a população microbiana no solo. Rev. Bras. Ciênc. Solo 14: 125-132.

Conte O., C.L. Wesp, I. Anghinoni, P.C.F. Carvalho, R. Levien & C. Nabinger. 2011. Densidade, agregação e frações e carbono de um argissolo sob pastagem natural submetida a níveis de ofertas de forragem por longo tempo. Rev. Bras. Ciênc. Solo 35:

-587.

Côrrea F.L. & G.E. Maraschin. 1994. Crescimento e desaparecimento de uma pastagem nativa sob diferentes níveis de oferta de forragem. Pesqui. Agropecu. Bras. 29: 1617-1623.

Cruz P., F.L.F. DE Quadros, J.P. Theau, A. Frizzo, C. Jouany, M. Duru & P.C.F. Carvalho. 2010. Leaf Traits as Functional

escriptors of the Intensity of Continuous Grazing in Native Grasslands in the South of Brazil. Rangeland Ecol. Manag. 63: 350- 358.

Garnier E., S. Lavorel, P. Ansquer, H. Castro, P. Cruz, J. Dolezal, O. Eriksson, C. Fortunel , H. Freitas , C. Golodets, K. Grigulis, C. Jouany, E. Kazakou, J. Kigel, M. Kleyer, V. Lehsten, J. Leps, T.A. Meier, R. Pakeman, M. Papadimitriou, V.P. Papanastasis, H. Quested, F. Que´tier, M. Robson, C. Roumet, G. Rusch, C. Skarpe, M. Sternberg, J. Theau, A. Bault, D. Vile & M.P. Zarovali. 2006. Assessing the effects of land-use change on plaits traits, communities and ecosystems functioning in grasslands: a standardized methodology and lessons from an application to 11 European sites. Ann. Bot. 99: 967-985.

Goret, T. 2005. Influence de l'intensité de pâturage et de la richesse du sol sur la biodiversité des prairies naturelles du Campos au sud du Brésil. Mémoire d’études en Agronomie Université Catholique de Louvain. pp.151.

Holt J.A. 1997. Grazing pressure and soil carbon, microbial biomass and enzyme activities in semi-arid northeastern Australia. Appl. Soil Ecol. 5:143-149.

Lemaire G. 2007. Research priorities for grassland science: the need of long term integrated experiments networks. Rev. Bras. Zootec. 36: 93-100.

Moreira F.M.S. & J.O. Siqueira. 2003. Microbiologia e bioquímica do solo. Lavras, Universidade Federal de Lavras.

pp. 625.

Mott G.O. & H.L. Lucas. 1952. The desing, conduct and interpretation of grazing trials on cultivated or improved pastures. In: International Grassland Congress, 6, Pensylvania. Proceedings Pensylvania. pp. 1380-1385.

Murphy D.V., W.R. Cookson, M. Braimbridge, P. Marschner, D.L. Jones, E.A. Stockdale & L.K. Abbott. 2011. Relationships between soil organic matter and the soil microbial biomass (size, functional diversity, and community structure) In: crop and pasture systems in a semi-arid environment. Soil Res. 49: 582-594.

Neves F.P., P.C.F. Carvalho, C. Nabinger, A.V.A. Jacques, I. Carassai, F. Tentardini. 2009. Estratégias de manejo da oferta de forragem para recria de novilhas em pastagem natural. Rev. Bras. Zootec. 38: 1532-1542.

Vance E.D., P.C. Brookes & D.S. Jenkinson. 1987. An extraction method for measuring soil microbial biomass. Soil Biol.Biochem. 19: 703-707.

Published

2020-03-21