Contrasting Soil pH Effects on Fungal and Bacterial Growth Suggest Functional Redundancy in Carbon Mineralization

Applied and Environmental Microbiology - Tập 75 Số 6 - Trang 1589-1596 - 2009
Johannes Rousk1, Philip C. Brookes2, Erland Bååth1
1Department of Microbial Ecology, Lund University, Ecology Building, SE-223 62 Lund, Sweden
2Soil Science Department, Rothamsted Research, Harpenden, Hertfordshire ALS 2JQ, United Kingdom

Tóm tắt

ABSTRACT The influence of pH on the relative importance of the two principal decomposer groups in soil, fungi and bacteria, was investigated along a continuous soil pH gradient at Hoosfield acid strip at Rothamsted Research in the United Kingdom. This experimental location provides a uniform pH gradient, ranging from pH 8.3 to 4.0, within 180 m in a silty loam soil on which barley has been continuously grown for more than 100 years. We estimated the importance of fungi and bacteria directly by measuring acetate incorporation into ergosterol to measure fungal growth and leucine and thymidine incorporation to measure bacterial growth. The growth-based measurements revealed a fivefold decrease in bacterial growth and a fivefold increase in fungal growth with lower pH. This resulted in an approximately 30-fold increase in fungal importance, as indicated by the fungal growth/bacterial growth ratio, from pH 8.3 to pH 4.5. In contrast, corresponding effects on biomass markers for fungi (ergosterol and phospholipid fatty acid [PLFA] 18:2ω6,9) and bacteria (bacterial PLFAs) showed only a two- to threefold difference in fungal importance in the same pH interval. The shift in fungal and bacterial importance along the pH gradient decreased the total carbon mineralization, measured as basal respiration, by only about one-third, possibly suggesting functional redundancy. Below pH 4.5 there was universal inhibition of all microbial variables, probably derived from increased inhibitory effects due to release of free aluminum or decreasing plant productivity. To investigate decomposer group importance, growth measurements provided significantly increased sensitivity compared with biomass-based measurements.

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Tài liệu tham khảo

10.1016/j.soilbio.2007.10.014

10.1016/j.soilbio.2008.03.020

Anderson, J. P. E., and K. H. Domsch. 1973. Quantification of bacterial and fungal contributions to soil respiration. Arch. Microbiol.93:113-127.

10.1016/S0038-0717(99)00103-0

10.1002/jpln.200321302

10.1016/S0038-0717(99)00015-2

The soil at Rothamsted Lawes Agricultural Trust. 1995

10.1016/0038-0717(92)90066-7

Bååth, E. 1994. Thymidine and leucine incorporation in soil bacteria with different cell-size. Microb. Ecol.27:267-278.

10.1007/s002489900118

10.1016/S0038-0717(01)00137-7

10.1016/S0038-0717(03)00154-8

Bååth, E., and K. Arnebrant. 1995. Growth rate and response of bacterial communities to pH in limed and ash-treated forest soils. Soil Biol. Biochem.26:995-1001.

10.1016/S0038-0717(01)00073-6

10.1016/S0038-0717(01)00086-4

10.2307/2937317

10.1016/S0038-0717(98)00050-9

10.1016/j.soilbio.2007.09.007

10.1111/j.2006.0030-1299.15178.x

10.3354/ame013141

10.1007/BF00011055

10.1016/j.soilbio.2006.01.008

10.1073/pnas.0507535103

10.1128/aem.46.3.758-761.1983

10.1016/0038-0717(93)90066-K

Technical paper ISRIC 20. 1989

10.1007/BF00384433

10.1016/0038-0717(93)90113-P

10.1007/BF00397184

10.1016/S0929-1393(01)00141-X

Griffiths, B. S., K. Ritz, N. Ebblewhite, and G. Dobson. 1999. Soil microbial community structure: effects of substrate loading rates. Soil Biol. Biochem.31:145-153.

Han, W., S. J. Kemmitt, and P. C. Brookes. 2008. Soil microbial biomass and activity in Chinese tea gardens of varying stand age and productivity. Soil Biol. Biochem.39:1468-1478.

10.1016/j.baae.2004.09.002

10.1046/j.1469-8137.2003.00867.x

10.1007/s00442-006-0562-5

10.2307/1939274

Hunt, H. W., D. C. Coleman, E. R. Ingham, R. E. Ingham, E. T. Elliott, J. C. Moore, S. L. Rose, C. P. P. Reid, and C. R. Morley. 1987. The detrital food web in a shortgrass prairie. Biol. Fertil. Soils3:57-68.

10.1016/S0038-0717(99)00191-1

10.1016/j.soilbio.2008.08.017

10.1016/j.soilbio.2007.06.021

10.1016/j.soilbio.2004.10.001

10.1016/j.soilbio.2005.08.006

10.1128/aem.49.3.599-607.1985

10.1016/j.soilbio.2008.05.021

10.1016/S0038-0717(99)00210-2

10.1016/j.pedobi.2005.05.008

10.2307/1940954

10.1007/s00442-007-0735-x

10.1046/j.1469-8137.2003.00810.x

10.1128/AEM.64.6.2173-2180.1998

10.1016/j.femsec.2004.10.002

10.1128/AEM.70.5.2966-2973.2004

10.1111/j.1574-6941.2007.00398.x

10.1016/j.soilbio.2007.03.023

10.1111/j.1574-6941.2008.00440.x

10.1007/s00248-008-9444-1

10.1016/S0038-0717(00)00009-2

Saetre, P., and J. M. Stark. 2005. Microbial dynamics and carbon and nitrogen cycling following re-wetting of soils beneath two semi-arid plant species. Oeologia142:247-260.

10.1016/S0038-0717(03)00015-4

10.2136/sssaj2004.0347

10.1016/j.soilbio.2005.07.010

SMSS technical monograph 19. 1992

10.1016/j.soilbio.2007.03.009

10.1007/s003740050325

10.1016/j.foreco.2005.11.002

10.1007/s003740050533

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Applied and Environmental Microbiology

Tập 75 Số 6

1589-1596

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