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001-es BibID:BIBFORM056995
Első szerző:Kotroczó Zsolt (biológus, ökológus)
Cím:Soil enzyme activity in response to long-term organic matter manipulation / Zsolt Kotroczó, Zsuzsa Veres, István Fekete, Zsolt Krakomperger, János Attila Tóth, Kate Lajtha, Béla Tóthmérész
Megjegyzések:Enzymes are considered to be a key soil component catalysing important transformations related todecomposition and nutrient turnover, and their activity in soil can be used as a measure of soil health. Aspart of the Síkf}okút DIRT (Detritus Input and Removal Treatments) Project in a temperate deciduousforest in northern Hungary, we examined the extent to which enzyme activity in soil is influenced byboth the quality and quantity of plant detrital inputs. DIRT treatments include doubling of leaf litter andwoody debris inputs as well as removal of litter and trenching to prevent root inputs. Our objective wasto examine seasonal dynamics of soil phosphatase and b-glucosidase activities and to determine theeffects of detrital manipulations on these dynamics. We found that the litter additions did not affectenzyme activities, but removal of roots caused significant decreases in enzyme activities. We concludethat plant-induced changes to soil enzyme activities are driven primarily by readily available, labilecarbon provided by root turnover and root exudation rather than by aboveground detrital inputs.However, these results could also have been affected by changes in soil chemistry with detrital inputremoval: after only 6 years of litter removal, soil cation content decreased and soils became more acidic,both of which could inhibit enzyme activity. The soil phosphatase and b-glucosidase enzymes measuredshowed similar seasonal dynamics. Both enzymes showed the highest activities in spring coincident withhigh soil moisture and, presumably, high root activity. The minimal response of soil enzyme activity todramatic litter additions suggests a level of resilience in ecosystem function in this forest, and suggeststhat aboveground litter is not a significant source of labile carbon to microbes in the mineral soil.
Tárgyszavak:Természettudományok Környezettudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Soil Biology & Biochemistry. - 70 (2014), p. 237-243. -
További szerzők:Veres Zsuzsa (1984-) (környezetkutató) Fekete István Krakomperger Zsolt (1980-) (biológia tanár) Tóth János Attila (1945-) (ökológus) Lajtha, Kate Tóthmérész Béla (1960-) (ökológus)
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001-es BibID:BIBFORM031266
Első szerző:Tóth János Attila (ökológus)
Cím:Effect of Litter Fall on Soil Nutrient Content and pH, and its Consequences in View of Climate Change (Síkfőkút DIRT Project) / János Attila Tóth, Péter Tamás Nagy, Zsolt Krakomperger, Zsuzsa Veres, Zsolt Kotroczó, Sándorné Kincses, István Fekete, Mária Papp, Kate Lajtha
ISSN:1786-691X 1787-064X
Megjegyzések:In the DIRT (Detritus Input and Removal Treatment) field experiments established at the Síkfőkút Site (North Hungary) in October 2000, an experiment was initiated to study the long-termeffects of litter quality and quantity on pH and nutrient content (organic carbon, N forms, PO43?, K+,Mg2+, Ca2+) of soil in a Quercetum petraeae-cerris forest. An eight-year litter manipulationdemonstrated a close connection between the changes in pH and Mg2+ and Ca2+ concentration. Thedecline of litter production, the decrease of the soil pH due to lower Mg2+ and Ca2+ input lead toconsequent reduction of soil buffering capacity. The acidification interferes with the decompositionprocess of litter and humus compounds. Our results suggest decreases in organic matter content, totalN, Ca2+ and Mg2+ concentrations in the soil as a consequence of decline in forest litter productioninduced by climate change and a resulting degradation of the soil over a longer period.
Tárgyszavak:Természettudományok Környezettudományok idegen nyelvű folyóiratközlemény hazai lapban
Megjelenés:Acta Silvatica et Lignaria Hungarica. - 7 (2011), p. 75-86. -
További szerzők:Nagy Péter Tamás (1970-) (vegyész) Krakomperger Zsolt (1980-) (biológia tanár) Veres Zsuzsa (1984-) (környezetkutató) Kotroczó Zsolt (1975-) (biológus, ökológus) Kincses Sándorné (1964-) (agrokémia) Fekete István Papp Mária (1952-) (biológus, botanikus) Lajtha, Kate
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001-es BibID:BIBFORM057922
Első szerző:Veres Zsuzsa (környezetkutató)
Cím:Soil extracellular enzyme activities are sensitive indicators of detrital inputs and carbon availability / Zsuzsa Veres, Zsolt Kotroczó, István Fekete, János Attila Tóth, Kate Lajtha, Kimberly Townsend, Béla Tóthmérész
Megjegyzések:In a litter manipulation experiment in a temperate deciduous oak forest in Central Europe, we examinedsoil carbon contents and density fractions, as well as b-glucosidase and polyphenol oxidase enzymeactivities, which play central roles in the degradation of litter and soil organic matter. Our measurementswere taken in the DIRT (detritus input and removal treatments) plots, where manipulations includedoubling of leaf litter or woody debris inputs, as well as removal of litter, trenching to prevent root inputs,and removal of all litter inputs. After 10 years of manipulation, soil C content did not vary predictablyamong plots, although the amount of light fraction material was greater in control and litter additionplots compared to litter removal plots. Even after 10 years of litter addition, there were no significantdifferences in activities of either enzyme in double litter plots compared to control plots, a resultconsistent with other observed measures of microbial activity. However, removal of roots and littercaused significant decreases in b-glucosidase activities very quickly, and these differences increased overtime. However, polyphenol oxidase activities were not significant different among treatments. Enzymeactivities were not correlated with total soil carbon contents, but activities of both enzymes weresignificantly and positively related to the amount of light fraction carbon, suggesting that enzymesrespond to increases in labile carbon availability.
Tárgyszavak:Természettudományok Környezettudományok idegen nyelvű folyóiratközlemény külföldi lapban
Extracellular enzymes
Litter manipulation
Polyphenol oxidase
Megjelenés:Applied Soil Ecology. - 92 (2015), p. 18-23. -
További szerzők:Kotroczó Zsolt (1975-) (biológus, ökológus) Fekete István Tóth János Attila (1945-) (ökológus) Lajtha, Kate Townsend, Kimberly Tóthmérész Béla (1960-) (ökológus)
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