Short communication: Biochemically active humic substances in contrasting agricultural managements

Emilio Benitez, Rogelio Nogales, Serena Doni, Grazia Masciandaro, Beatriz Moreno

Abstract


 

Because their crucial role in several soil biochemical cycles and their fast response to changes in soil management, extracellular enzymes activities are widely used as sensitive indicators of ecological change and soil quality. The aim of this work was to determine the effects of soil management on the stable pool of soil carbon cycling enzymes as indicators of essential functions. For this, extracellular β-glucosidase enzymes bounded by humic acids (C higher than 104 Da) were used to compare four long-term contrasting agricultural managements in a rainfed olive orchard representative of semi-arid Mediterranean habitats. The study was conducted for 30 years by designing a random-block of four treatments (nude vs. covered soils) and four replicates. Maintaining cover crops through fall, winter and early spring provoked a more stable and active pool of extracellular β-glucosidase in soils only if spontaneous vegetation was managed with mechanical methods. When herbicides were used during 30 years, the pattern of the molecular composition and activity of humus β-glucosidase complexes were similar in covered and nude soils, although higher activity was retrieved in the former. Tillage management increased carbon mineralization and the level of humic substances and the activity of β-glucosidase humic-bound were quite lower than in the rest of treatments. Given the ecological role of extracellular soil carbon cycling enzymes, the characterization of humus β-glucosidase complexes could be an adequate indicator of sustainability of agricultural management systems.



Keywords


Olea europaea; β-glucosidase enzyme; humic substances; sustainability; cover spontaneous vegetation

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References


Benítez E, Nogales R, Masciandaro G, Ceccanti B, 2000. Isolation by isoelectric focusing of humic urease complexes from earthworm (Eisenia fetida)-processed sewage sludges. Biol Fertil Soils 31: 489-493. http://dx.doi.org/10.1007/s003740000197

Ceccanti B, Nannipieri P, Cervelli S, Sequi P, 1978. Fractionation of humus–urease complexes. Soil Biol Biochem 10: 39-45. http://dx.doi.org/10.1016/0038-0717(78)90008-1

Ceccanti B, Alcaniz-Baldellou JM, Gispert-Negrell M, Gassiot-Matas M, 1986. Characterization of organic matter from two different soils by pyrolysis–gas chromatography and isoelectric focusing. Soil Sci 142: 83-90. http://dx.doi.org/10.1097/00010694-198608000-00004

Ceccanti B, Bonmati-Pont M, Nannipieri P, 1989. Microdetermination of protease activity in humic bands of different sizes after analytical isoelectric focusing. Biol Fert Soils 7: 202-206. http://dx.doi.org/10.1007/BF00709649

Ceccanti B, Masciandaro G, 2003. Stable humus-enzyme nucleus: the last barrier against soil desertification. In: Preserving soil quality and soil biodiversity-the role of surrogate indicators; Lobo MC, Ibanez JJ (eds), pp: 77-82. CSIC-IMIA, Madrid.

Ceccanti B, Doni S, Macci C, Cercignani G, Masciandaro G, 2008. Characterization of stable humic–enzyme complexes of different soil ecosystems through analytical isoelectric focusing technique (IEF). Soil Biol Biochem 40: 2174-2177. http://dx.doi.org/10.1016/j.soilbio.2008.02.004

Doni S, Macci C, Chen H, Masciandaro G, Ceccanti B, 2012. Isoelectric focusing of β-glucosidase humic-bound activity in semi-arid Mediterranean soils under management practices. Biol Fertil Soils 48: 183-190. http://dx.doi.org/10.1007/s00374-011-0615-8

FAO, 1998. World Reference Base for Soil Resources. World Soil Resources Reports 84. FAO-ISRIC-ISSS, Roma. http://www.fao.org/docrep/W8594E/w8594e00.htm.

Fedtke C, 1982. Biochemistry and physiology of herbicide action. Springer, Berlin. http://dx.doi.org/10.1007/978-3-642-68375-6

Garcia C, Hernandez T, Costa F, Ceccanti B, Masciandaro G, Calcinai M, 1993. Evaluation of the organic matter of raw and composted municipal wastes. Soil Sci Plant Nutr 39: 99-108. http://dx.doi.org/10.1080/00380768.1993.10416979

Govi M, Ciavatta C, Gessa C, 1994. Evaluation of the stability of the organic matter in slurries, sludges and composts using humification parameters and isoelectric focusing. In: Humic substances in the global environment and implications on human health; Senesi S, Miano TM (eds). pp: 1311-1316. Elsevier Sci., Amsterdam.

Hayano K, Tubaki K, 1985. Origin and properties of β-glucosidase activity of a tomato-field. Soil Biol Biochem 17: 553-557. http://dx.doi.org/10.1016/0038-0717(85)90024-0

Kane D, 2015. Carbon sequestration potential on agricultural lands: A review of current science and available practices. In association with National Sustainable Agriculture Coalition, Breakthrough Strategies and Solutions, LLC. http://sustainableagriculture.net/publications/

Moreno B, Garcia-Rodriguez S, Cañizares R, Castro J, Benitez E. 2009. Rainfed olive farming in south-eastern Spain: Long-term effect of soil management on biological indicators of soil quality. Agric Ecosyst Environ 131: 333-339. http://dx.doi.org/10.1016/j.agee.2009.02.011

Nannipieri P, Sequi P, Fusi P, 1996. Humus and enzyme activity. In: Humic substances in terrestrial ecosystems; Piccolo A (ed), pp: 293-328. Elsevier, Amsterdam. http://dx.doi.org/10.1016/B978-044481516-3/50008-6

Nannipieri P, Giagnoni L, Renella G, Puglisi E, Ceccanti B, Masciandaro G, Fornasier F, Moscatelli MC, Marinari S, 2012. Soil enzymology: classical and molecular approaches. Biol Fertil Soils 48: 743-762. http://dx.doi.org/10.1007/s00374-012-0723-0

Riah W, Laval K, Laroche-Ajzenberg E, Mougin C, Latour X, Trinsoutrot-Gattin I, 2014. Effects of pesticides on soil enzymes: A review. Environ Chem Lett 12: 257-273. http://dx.doi.org/10.1007/s10311-014-0458-2

Tabatabai MA, Bremner JM, 1969. Use of ρ-nitrophenol phosphate in assay of soil phosphatase activity. Soil Biol Biochem 1: 301-307. http://dx.doi.org/10.1016/0038-0717(69)90012-1

Tiemann LK, Grandy AS, Atkinson EE, Marin-Spiotta E, McDaniel MD, 2015. Crop rotational diversity enhances belowground communities and functions in an agroecosystem. Ecol Lett 18: 1461-0248. http://dx.doi.org/10.1111/ele.12453

Yeomans JC, Bremner JM, 1988. A rapid and precise method for routine determination of organic carbon in soil. Soil Sci Plant Anal 19: 1467-1476. http://dx.doi.org/10.1080/00103628809368027




DOI: 10.5424/sjar/2016143-8431