Leaching of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) in mor humus as affected by temperature and pH

Andersson, Stefan; Nilsson, Staffan; Saetre, Peter

doi:10.1016/s0038-0717(99)00103-0

Cited by 251 publications

(123 citation statements)

References 26 publications

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“…Furthermore, the role of enzymatic activity, i.e., a primary biological control over DOC production, is consistent with the negative correlation between molecular weight of dissolved organic matter and ␤-glucosidase activity (r ϭ Ϫ0.64, P ϭ 0.03; n ϭ 12) as well as with the positive correlation between CO 2 emission and final DOC concentration (r ϭ 0.63, P ϭ 0.03; n ϭ 12) (28,29).…”

Section: Figsupporting

confidence: 65%

Atmospheric nitrogen deposition promotes carbon loss from peat bogs

Bragazza

Freeman

Jones

et al. 2006

Proc. Natl. Acad. Sci. U.S.A.

385

260

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Peat bogs have historically represented exceptional carbon (C) sinks because of their extremely low decomposition rates and consequent accumulation of plant remnants as peat. Among the factors favoring that peat accumulation, a major role is played by the chemical quality of plant litter itself, which is poor in nutrients and characterized by polyphenols with a strong inhibitory effect on microbial breakdown. Because bogs receive their nutrient supply solely from atmospheric deposition, the global increase of atmospheric nitrogen (N) inputs as a consequence of human activities could potentially alter the litter chemistry with important, but still unknown, effects on their C balance. Here we present data showing the decomposition rates of recently formed litter peat samples collected in nine European countries under a natural gradient of atmospheric N deposition from Ϸ0.2 to 2 g⅐m ؊2 ⅐yr ؊1 . We found that enhanced decomposition rates for material accumulated under higher atmospheric N supplies resulted in higher carbon dioxide (CO2) emissions and dissolved organic carbon release. The increased N availability favored microbial decomposition (i) by removing N constraints on microbial metabolism and (ii) through a chemical amelioration of litter peat quality with a positive feedback on microbial enzymatic activity. Although some uncertainty remains about whether decay-resistant Sphagnum will continue to dominate litter peat, our data indicate that, even without such changes, increased N deposition poses a serious risk to our valuable peatland C sinks.decomposition ͉ global change ͉ litter peat ͉ CO2 P eatlands cover 2-3% of the land's surface, store approximately one-third of all soil carbon (C) (390-455 Pg), and currently act as sinks for atmospheric C (1, 2). The ability of peatlands to sequester atmospheric C resides in the long-term accumulation of partially decomposed organic matter (i.e., peat). Indeed, acidic water conditions, low soil temperature, frequent waterlogging, and low nutrient quality of plant litter impair decomposition of plant litter, favoring its accumulation (3). In peatlands exclusively fed by atmospheric deposition (i.e., bogs) (1), the accumulated peat is dominated by the remnants of the mosses of the genus Sphagnum, which produce a litter poor in nutrients and highly enriched in organochemical compounds such as uronic acids (4) and polyphenols (5) with a strong inhibitory effect on microbial activity and vascular plants (3). As such, Sphagnum plants form the bulk of living and dead biomass in bog ecosystems (3).Because of the strict dependence of bogs on atmospheric deposition as a source of nutrients (1), the increasing availability of biologically reactive nitrogen (N) from industrial and agricultural activities (6) could potentially alter the chemical quality of plant litter with consequent effects on the amount of C released during litter decomposition. Accordingly, an understanding of the mechanisms of bog soil C response to changing N availability is essential for assessing the capa...

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Section: Figsupporting

confidence: 65%

Atmospheric nitrogen deposition promotes carbon loss from peat bogs

Bragazza

Freeman

Jones

et al. 2006

Proc. Natl. Acad. Sci. U.S.A.

385

260

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“…It is commonly known that pH has a major influence on the amount of organic matter present in the soil. According to literature, an increase in pH leads to an increase in organic matter solubility, while soil acidification can have either a positive or negative effect (Andersson et al, 2000). However, the content of soil organic matter depends on the balance between many environmental processes and factors that could be the cause of the low dependence between C org and pH in this study.…”

Section: Resultsmentioning

confidence: 71%

Analysis of the sorption properties of different soils using water vapour adsorption and potentiometric titration methods

Skic¹,

Boguta²,

Sokołowska³

2016

International Agrophysics

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A b s t r a c t. Parameters of specific surface area as well as surface charge were used to determine and compare sorption properties of soils with different physicochemical characteristics. The gravimetric method was used to obtain water vapour isotherms and then specific surface areas, whereas surface charge was estimated from potentiometric titration curves. The specific surface area varied from 12.55 to 132.69 m 2 g -1 for Haplic Cambisol and Mollic Gleysol soil, respectively, and generally decreased with pH (R=0.835; α = 0.05) and when bulk density (R=-0.736; α = 0.05) as well as ash content (R=-0.751; α = 0.05) increased. In the case of surface charge, the values ranged from 63.00 to 844.67 µmol g -1 Haplic Fluvisol and Mollic Gleysol, respecively. Organic matter gave significant contributions to the specific surface area and cation exchange capacity due to the large surface area and numerous surface functional groups, containing adsorption sites for water vapour molecules and for ions. The values of cation exchange capacity and specific surface area correlated linearly at the level of R=0.985; α = 0.05. K e y w o r d s: potentiometric titration, water vapour isotherms, cation exchange capacity, specific surface area INTRODUCTION

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“…This, however, depends on the rate and time of waste or fertilizer application. Anderson et al [12] found organic nitrogen leaching The total amount of inorganic nitrogen (NH 4 , NO 2 and NO 3 nitrogen) applied to each soil was 55 mg. However, between 59.00-76.30 mg were collected in the leachates, depending on the soil type and soil column depth.…”

Section: Discussionmentioning

confidence: 98%

Potential Air and Groundwater Pollution from Continuous High Land Application of Cheese Whey

Ghaly¹,

Rushton²,

Mahmoud³

2007

American J. of Applied Sciences

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Experiments were performed, using eighteen 280 cm deep soil columns with 20 cm inside diameter, to determine the relative amounts of nitrogenous compounds leached and volatilized from soils receiving high application rates of cheese whey during two seasons. Three soils (loamy sand, sandy loam and sandy clay loam) and two cheese whey application rates (560 and 840 kg-N ha¯1), that provided twice and three times the nitrogen requirement for corn crop, were investigated. The leaching and volatilization processes were monitored over a period of five months each season. The concentrations of nitrogenous compounds in the leachates obtained from three soils decreased with time and the soil type and whey application rate did not have any significant effect on the soil removal efficiency of these compounds. However, higher concentrations were observed in the second season of application. The decline in the ammonium nitrogen concentrations in the absence of plants and the initial increase in the nitrite nitrogen and nitrate nitrogen concentrations indicated that the nitrification process had taken place. The organic nitrogen losses in the leachates were 3.02-4.14 kg h¯1 (0.54-0.74 % of the initial total nitrogen). The total inorganic (NH 4 , NO 2 , NO 3 ) nitrogen losses in the leachates were 59-76 mg which is higher than the initial concentration of 55 mg indicating that the mineralization process had taken place. Volatilization of NH 3 was independent of soil type and whey application rate. About 3.41 g¯1ha¯1 (0.59 % of the initial total nitrogen) of nitrogen was lost to the atmosphere through volatilization Nitrite and nitrate are highly soluble and easily leach out of soil solution. Therefore, continuous application of cheese whey at higher rates may result in ground water contamination and eventually becomes a threat to human and animal health.

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Leaching of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) in mor humus as affected by temperature and pH

Cited by 251 publications

References 26 publications

Atmospheric nitrogen deposition promotes carbon loss from peat bogs

Atmospheric nitrogen deposition promotes carbon loss from peat bogs

Analysis of the sorption properties of different soils using water vapour adsorption and potentiometric titration methods

Potential Air and Groundwater Pollution from Continuous High Land Application of Cheese Whey

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