Effect of Soil Respiration on Light Fraction-C and N Availability in Soil Applied with Organic Matter

Soil organic matter is considered a key attribute for a sustainable agricultural production and is influenced by the quantity and quality of the crop residue deposited on the soil surface. Therefore, different crop rotations could change the soil organic matter pools. The objectives of this study were to evaluate the soil carbon pools obtained by chemical and physical fractionation methods and the humification index under different crop rotations in a no-till system. We test the following hypothesis: a) the distribution of C and N among the soil organic matter fractions depends on plant species rotation schemes and; b) labile fractions are more sensitive to the input of crop residues and therefore, more suitable for evaluating the impact of different crop rotations in the soil organic matter quality. We evaluated four crop sequences (corn/corn/corn; corn/wheat/corn; soybean/wheat/corn and soybean/corn/corn) in a no-till system. A five-year reforested area was used as reference. We determined the total C and N contents, the mineral-associated C and N, the light fraction of C and N, the labile carbon extracted with KMnO4 and the soil organic matter humification index. We found narrow differences between the crop rotation systems in the total C and N levels, the mineral-associated C and N fractions and the labile C extracted with KMnO4. The diversification of the agricultural system with soybean in crop rotation favored the accumulation of light fraction C and N in the soil that were more efficient to provide information about the changes in the soil organic matter quality.

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Effects of changing C and N availability on soil respiration dynamics in a temperate grassland in northern China

Geoderma ◽

10.1016/j.geoderma.2018.03.020 ◽

2018 ◽

Vol 329 ◽

pp. 20-26 ◽

Cited By ~ 1

Author(s):

Yunlong He ◽

Yuchun Qi ◽

Yunshe Dong ◽

Qin Peng ◽

Shufang Guo ◽

...

Keyword(s):

Soil Respiration ◽

Northern China ◽

Temperate Grassland ◽

N Availability ◽

C And N

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Free light fraction carbon and nitrogen, a physically uncomplexed soil organic matter distribution within subtropical grass and leucaena–grass pastures

Soil Research ◽

10.1071/sr18162 ◽

2018 ◽

Vol 56 (8) ◽

pp. 820 ◽

Cited By ~ 2

Author(s):

K. A. Conrad ◽

R. C. Dalal ◽

D. E. Allen ◽

R. Fujinuma ◽

Neal W. Menzies

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Soil Depth ◽

Light Fraction ◽

Grass Species ◽

Pasture Grass ◽

Total N ◽

Δ13c And Δ15n ◽

Organic C ◽

C And N

Quantifying the size and turnover of physically uncomplexed soil organic matter (SOM) is crucial for the understanding of nutrient cycling and storage of soil organic carbon (SOC). However, the C and nitrogen (N) dynamics of SOM fractions in leucaena (Leucaena leucocephala)–grass pastures remains unclear. We assessed the potential of leucaena to sequester labile, free light fraction (fLF) C and N in soil by estimating the origin, quantity and vertical distribution of physically unprotected SOM. The soil from a chronosequence of seasonally grazed leucaena stands (0–40 years) was sampled to a depth of 0.2m and soil and fLF were analysed for organic C, N and δ13C and δ15N. On average, the fLF formed 20% of SOC and 14% of total N stocks in the upper 0.1m of soil from leucaena rows and showed a peak of fLF-C and fLF-N stocks in the 22-year-stand. The fLF δ13C and fLF δ15N values indicated that leucaena produced 37% of fLF-C and 28% of fLF-N in the upper 0.1m of soil from leucaena rows. Irrespective of pasture type or soil depth, the majority of fLF-C originated from the accompanying C4 pasture-grass species. This study suggests that fLF-C and fLF-N, the labile SOM, can form a significant portion of total SOM, especially in leucaena–grass pastures.

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Soil Respiration, Microbial Biomass C and N Availability in a Sandy Soil Amended with Clay and Residue Mixtures

Pedosphere ◽

10.1016/s1002-0160(15)60073-x ◽

2016 ◽

Vol 26 (5) ◽

pp. 643-651 ◽

Cited By ~ 5

Author(s):

Sharmistha PAL ◽

Petra MARSCHNER

Keyword(s):

Microbial Biomass ◽

Soil Respiration ◽

Sandy Soil ◽

Microbial Biomass C ◽

N Availability ◽

C And N

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Straw removal increases the light fraction and mineralizable C and N compared with moldboard ploughing

Canadian Journal of Soil Science ◽

10.4141/s06-035 ◽

2007 ◽

Vol 87 (1) ◽

pp. 113-115 ◽

Cited By ~ 4

Author(s):

Y K Soon

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Microbial Biomass ◽

Crop Production ◽

Light Fraction ◽

Straw Management ◽

N Retention ◽

Cereal Straw ◽

C And N ◽

Straw Incorporation

An earlier study indicated that cereal straw may be removed after harvest without affecting crop production, soil organic matter and microbial biomass. Further measurements of early indicators of changes in soil organic matter, viz., the light fraction and mineralizable C and N, confirm that straw removal is superior to straw incorporation with moldboard ploughing, and comparable to straw incorporation by disking, in C and N retention and turnover. Key words: Carbon, light fraction, mineralization, nitrogen, straw management

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Changes in Soil Labile Organic Matter as Affected by 50 Years of Fertilization with Increasing Amounts of Nitrogen

Agronomy ◽

10.3390/agronomy11102026 ◽

2021 ◽

Vol 11 (10) ◽

pp. 2026

Author(s):

Nikola Koković ◽

Elmira Saljnikov ◽

Frank Eulenstein ◽

Dragan Čakmak ◽

Aneta Buntić ◽

...

Keyword(s):

Organic Matter ◽

Microbial Biomass ◽

Quality Parameters ◽

Light Fraction ◽

Microbial Biomass C ◽

Microbial Biomass N ◽

Sensitivity Index ◽

Strong Impact ◽

Labile Organic Matter ◽

C And N

Microbially mediated soil organic matter is an extremely sensitive pool that indicates subtle changes in the quality parameters responsible for the soil’s ecological and productive functions. Fifty years of mineral fertilization of a wheat-corn cropping system has a strong impact on soil quality parameters. The goal of the research was to study the dynamics and quality of soil biological parameters affected by increasing amounts of mineral nitrogen. Soil respiration, potentially mineralizable C and N, microbial biomass C and N and light-fraction OM on Cambisol were analyzed in the following treatments: (1) Control (without fertilization); (2) NPK (60/51/67); (3) NPK (90/51/67); (4) NPK (120/51/67); (5) NPK (150/51/67 kg ha−1). The parameters studied were significantly affected by the long-term application of mineral fertilizer compared with both the control and the adjacent native soil. The highest amounts of nitrogen (N150) did not significantly differ from N120 and N90 for most of the parameters studied. Potentially mineralizable C represented the largest labile carbon pool, while microbial biomass N was the largest labile nitrogen pool. The mineralization rates for C and N were oppositely distributed over the seasons. The sensitivity index correlated with the amount of light-fraction OM. The results give a deeper insight into the behavior and distribution of different pools of labile SOM in the agro-landscapes and can serve as a reliable basis for further research focused on zero soil degradation.

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Cultivation and grassland type effects on light fraction and total organic C and N in a Dark Brown Chernozemic soil

Canadian Journal of Soil Science ◽

10.4141/s02-028 ◽

2003 ◽

Vol 83 (2) ◽

pp. 145-153 ◽

Cited By ~ 36

Author(s):

S. S. Malhi ◽

S. Brandt ◽

K. S. Gill

Keyword(s):

Organic Matter ◽

Soil Samples ◽

Light Fraction ◽

Organic C ◽

Soil Layers ◽

Chernozemic Soil ◽

Annual Crops ◽

Grassland Type ◽

C And N ◽

Total Organic C

Light fraction of organic matter is a source of nutrients for plants and a substrate for microbes, while total organic matter is critical for optimum physical conditions and retention of nutrients and other chemicals in soil. The objective of this study was to evaluate the effects of cultivation and grassland type on light fraction and total C and N in a Dark Brown Chernozemic soil. Three paired-sets of soil samples, in five replications, were collected from three cultivated field areas under annual crops [mostly wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.)] and from three adjacent grassland areas. The three sets were a 30-yr-old bromegrass (Bromus inermis Leyss.)/alfalfa (Medicago sativa L.) dominated stand cut annually for hay (Lm) and cultivated area 1 (Ct1), an unbroken native grass stand having no vegetation removed (Ng) and cultivated area 2 (Ct2) and a bromegrass/crested wheatgrass (A gropyron cristatum L. Gaertn.) dominated stand on a land reverted to grassland 60 yr ago having no vegetation removed (Og) and cultivated area 3 (Ct3). Soil samples from the 0- to 5-cm, 5- to 10-cm, 10- to 15-cm, 15- to 20-cm and 20- to 30-cm depths were taken using a 4-cm-diameter coring tube sampler. Total organic C (TOC), total N (TN), light fraction organic C (LFOC) and light fraction N (LFN) in soil were determined and the equivalent mass technique was used to calculate their masses in different soil layers. Total mass (for all soil layers) was less in the cultivated areas compared to the grassland areas by 31 to 43% for TOC, by 84 to 85% for LFOC, by 15 to 34% for TN and by 82 to 84% for LFN. The effect of cultivation was much greater in the surface 5-cm depth compared to deeper soil layers. The proportions of LFOC in TOC and LFN in TN as well as the TOC:TN ratios were lower in the cultivated areas than in the grassland areas, whereas the LFOC:LFN ratios were similar in cultivated and grassland areas. The light fractions of C and N were thus more responsive to change from grassland to cultivation of annual crops compared to the total C and N. Within the grassland areas, the mass of TOC and TN in most of the soil layers was greater in the Lm compared to both Ng and Og areas, while the LFOC and LFN did not show the effect of grassland type. The differences in the mass of both total and light fraction C and N in the cultivated areas were small and generally not significant. The findings suggest that including legume in grassland stands can sequester more organic C and N into the soil even when used for hay production. Key words: Cultivated land, light fraction C and N, native grassland, total organic C and N

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Soil organic matter and the extracellular microbial matrix show contrasting responses to C and N availability

Soil Biology and Biochemistry ◽

10.1016/j.soilbio.2015.05.025 ◽

2015 ◽

Vol 88 ◽

pp. 257-267 ◽

Cited By ~ 30

Author(s):

M.A. Redmile-Gordon ◽

R.P. Evershed ◽

P.R. Hirsch ◽

R.P. White ◽

K.W.T. Goulding

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

N Availability ◽

C And N

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Characterizing organic matter retention for surface soils in eastern Canada using density and particle size fractions

Canadian Journal of Soil Science ◽

10.4141/s01-087 ◽

2003 ◽

Vol 83 (1) ◽

pp. 11-23 ◽

Cited By ~ 118

Author(s):

M. R. Carter ◽

D. A. Angers ◽

E. G. Gregorich ◽

M. A. Bolinder

Keyword(s):

Organic Matter ◽

Soil Depth ◽

Light Fraction ◽

Degree Of Saturation ◽

Soil Organic C ◽

Eastern Canada ◽

Organic C ◽

Size Fractions ◽

Capacity Level ◽

C And N

Interest in the storage of organic matter in terrestrial ecosystems has identified a need to better understand the accumulation and retention of organic C and N in soil. The proportions of C and N associated with clay and silt particles (i.e., “capacity level”), water-stable macro-aggregates (WSA) (>250 µm), particulate (POM) (>53 µm), and light fraction (LF) organic matter, for the 0- to 10-cm soil depth, were assessed at 14 agricultural experimental sites established on Gleysolic, Podzolic, Luvisolic , and Brunisolic soils in the cool, humid region of eastern Canada. Organic C and N in the clay plus silt particles was at or near the capacity level for soils with clay plus silt content < 40%. For soils with >60% clay plus silt, the degree of saturation was 65–70% indicating a potential for further organic C and N retention. The mean proportion of C and N found in the POM was 22 and 27%, whil e the LF organic matter contained 7 and 5% C and N, respectively. Mean soil WSA content, determined by wet-sieving analysis, was 42% for air-dry soil and 54% for wetted soil, and was significantly (P < 0.05) related to both soil clay plus silt (r = 0.65) and organic C (r = 0.54). Water-stable macro-aggregate C content was proportional to soil organic C (r = 0.96, P < 0.01). At four of the sites, where soil C and N were influenced by management, an increasing level of soil organic C and N was associated with both the clay plus silt particles and the POM fraction until the former was saturated. Once the capacity level was saturated, further organic C and N accumulation was associated with the POM fraction. Although stabilized organic C and N in soil exists as a continuum, both soil particle and particulate fractions provided a practical approach to monitor, quantify and differentiate the storage and retention of C and N in soils of eastern Canada. Key words: Soil organic matter, clay plus silt associated organic C and N, size fractions, particulate organic matter, light fraction organic matter, water-stable macro-aggregates, organic amendments, Canada

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Soil organic matter quality and aggregate stability under eight potato cropping sequences in a fine sandy loam of Prince Edward Island

Canadian Journal of Soil Science ◽

10.4141/s98-033 ◽

1999 ◽

Vol 79 (3) ◽

pp. 411-417 ◽

Cited By ~ 50

Author(s):

Denis A. Angers ◽

Linnell M. Edwards ◽

J. Brian Sanderson ◽

Nicole Bissonnette

Keyword(s):

Organic Matter ◽

High Frequency ◽

Prince Edward Island ◽

Sandy Loam ◽

Solanum Tuberosum L ◽

Aggregate Stability ◽

Red Clover ◽

Light Fraction ◽

Fine Sandy Loam ◽

C And N

Soil degradation and soil organic matter (SOM) reduction have long been suspected to occur under intensive potato (Solanum tuberosum L.) production in Prince Edward Island. Thus, this study was conducted to evaluate the effect of eight potato cropping sequences involving barley (Hordeum vulgare L.), ryegrass (Lolium multiflorum L.), red clover (Trifolium pratense L.) and barley under-seeded with red clover on aggregate stability and SOM properties of a Charlottetown fine sandy loam (Orthic Humo-Ferric Podzol). Total C and N, light-fraction (density < 1.7 g cm−3) C (LF-C) and light-fraction N (LF-N), microbial biomass C (MBC), carbohydrate content, alkaline phosphatase activity (APA) and aggregate stability were determined in the 0- to 15-cm soil layer in the 6th and 10th years of the trial. Average C and N contents were 20 to 27% greater in sequences that included 3 or 4 yr of potatoes and a high frequency of red clover than in a 9-yr potato sequence; and were attributed to the less frequent tillage and higher organic matter inputs associated with the forage component. The response for MBC, LF-C, LF-N and APA was greater than those for total C and N suggesting that the former parameters may better reveal SOM changes caused by variations in potato management than the latter. Light-fraction N was particularly sensitive to the inclusion of perennial legumes in the cropping sequence. Wet-aggregate stability was 33% higher after 6 yr in the sequence with 50% frequency of red clover than in the continuous potato system, but no effect was noted after 10 yr. The results of this study indicate that sequences which are limited to 30 to 40% of potatoes and have a high frequency of perennial forage such as red clover, lead to greater SOM content and quality of a Charlottetown fine sandy loam compared to continuous potatoes. Trends in aggregate stability generally followed those of SOM fractions but the effects were relatively smaller and varied with time. Key words: Potato, Solanum tuberosum L., soil aggregation, organic matter, carbon, nitrogen, light fraction, microbial biomass

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