Long-term partial substitution of chemical fertilizer with green manure regulated organic matter mineralization in paddy soil dominantly by modulating organic carbon quality

Abstract Soil organic matter (SOM) and its fractions play an important role in maintaining or improving soil quality and soil fertility. Therefore, the effects of a 34-year long-term fertilizer regime on six functional SOM fractions under a double-cropping rice paddy field of southern China were studied in the current paper. The field experiment included four different fertilizer treatments: chemical fertilizer alone (MF), rice straw residue and chemical fertilizer (RF), 30% organic manure and 70% chemical fertilizer (OM) and without fertilizer input as control (CK). The results showed that coarse unprotected particulate organic matter (cPOM), biochemically, physically–biochemically and chemically protected silt-sized fractions (NH-dSilt, NH-μSilt and H-dSilt) were the main carbon (C) storage fractions under long-term fertilization conditions, accounting for 16.7–26.5, 31.1–35.6, 16.2–17.3 and 7.5–8.2% of the total soil organic carbon (SOC) content in paddy soil, respectively. Compared with control, OM treatment increased the SOC content in the cPOM, fine unprotected POM fraction, pure physically protected fraction and physico-chemically protected fractions by 58.9, 106.7, 117.6 and 28.3%, respectively. The largest proportion of SOC to total SOC in the different fractions was biochemically protected, followed by chemically and unprotected, and physically protected were the smallest. These results suggested that a physical protection mechanism plays an important role in stabilizing C of paddy soil. In summary, the results showed that higher functional SOM fractions and physical protection mechanism play an important role in SOM cycling in terms of C sequestration under the double-cropping rice paddy field.

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The effects of cultivation on the composition of organic-matter and structural stability of soils

Soil Research ◽

10.1071/sr9950975 ◽

1995 ◽

Vol 33 (6) ◽

pp. 975 ◽

Cited By ~ 124

Author(s):

A Golchin ◽

P Clarke ◽

JM Oades ◽

JO Skjemstad

Keyword(s):

Organic Matter ◽

Chemical Composition ◽

Organic Carbon ◽

Organic Materials ◽

Aggregate Stability ◽

Soil Samples ◽

Modulus Of Rupture ◽

Dispersible Clay ◽

Different Soils

Soil samples were obtained from the surface horizons of five untilled sites and adjacent sites under short- and long-term cultivation. The soil samples were fractionated based on density and organic materials were concentrated in various fractions which enabled comparative chemical composition of the organic materials in cultivated and uncultivated sites by solid-state C-13 CP/MAS NMR spectroscopy. Changes in the nature of organic carbon with cultivation were different in different soils and resulted from variations in the chemistry of carbon inputs to the soils and a greater extent of decomposition of organic materials in cultivated soils. Differences in the chemical composition of organic carbon between cultivated and uncultivated soils resided mostly in organic materials occluded within aggregates, whereas the chemistry of organic matter associated with clay particles showed only small changes. The results indicate a faster decomposition of O-alkyl C in the cultivated soils. Wet aggregate stability, mechanically dispersible clay and modulus of rupture tests were used to assess the effects of cultivation on structural stability of soils. In four of five soils, the virgin sites and sites which had been under long-term pasture had a greater aggregate stability than the cultivated sites. Neither total organic matter nor total O-alkyl C content was closely correlated with aggregate stability, suggesting that only a part of soil carbon or carbohydrate is involved in aggregate stability. The fractions of carbon and O-alkyl C present in the form of particulate organic matter occluded within aggregates were better correlated with aggregate stability (r = 0.86** and 0.88**, respectively). Cultivation was not the dominant factor influencing water-dispersible clay across the range of soil types used in this study. The amount of dispersible clay was a function of total clay content and the percentage of clay dispersed was controlled by factors such as clay mineralogy, CaCO3 and organic matter content of soils. The tendency of different soils for hard-setting and crusting, as a result of structural collapse, was reflected in the modulus of rupture (MOR). The cultivated sites had significantly higher MOR than their non-tilled counterparts. The soils studied had different MOR due to differences in their physical and chemical properties.

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Temperature sensitivity of soil organic matter mineralization decreases with long‐term N fertilization: Evidence from four Q 10 estimation approaches

Land Degradation and Development ◽

10.1002/ldr.3496 ◽

2020 ◽

Vol 31 (6) ◽

pp. 683-693 ◽

Cited By ~ 6

Author(s):

Huadong Zang ◽

Evgenia Blagodatskaya ◽

Yuan Wen ◽

Lingling Shi ◽

Fei Cheng ◽

...

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Temperature Sensitivity ◽

N Fertilization ◽

Organic Matter Mineralization

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The carbon quality-temperature hypothesis does not consistently predict temperature sensitivity of soil organic matter mineralization in soils from two manipulative ecosystem experiments

Biogeochemistry ◽

10.1007/s10533-017-0384-z ◽

2017 ◽

Vol 136 (3) ◽

pp. 249-260 ◽

Cited By ~ 5

Author(s):

Lorien L. Reynolds ◽

Kate Lajtha ◽

Richard D. Bowden ◽

Bart R. Johnson ◽

Scott D. Bridgham

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Temperature Sensitivity ◽

Carbon Quality ◽

Organic Matter Mineralization

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Long-term measurements of carbonaceous aerosols in the Eastern Mediterranean: evidence of long-range transport of biomass burning

Atmospheric Chemistry and Physics ◽

10.5194/acp-8-5551-2008 ◽

2008 ◽

Vol 8 (18) ◽

pp. 5551-5563 ◽

Cited By ~ 126

Author(s):

J. Sciare ◽

K. Oikonomou ◽

O. Favez ◽

E. Liakakou ◽

Z. Markaki ◽

...

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Long Range ◽

Biomass Burning ◽

Water Soluble ◽

Long Range Transport ◽

Crete Island ◽

Yearly Average ◽

Range Transport

Abstract. Long-term (5-year) measurements of Elemental Carbon (EC) and Organic Carbon (OC) in bulk aerosols are presented here for the first time in the Mediterranean Basin (Crete Island). A multi-analytical approach (including thermal, optical, and thermo-optical techniques) was applied for these EC and OC measurements. Light absorbing dust aerosols were shown to poorly contribute (+12% on a yearly average) to light absorption coefficient (babs) measurements performed by an optical method (aethalometer). Long-range transport of agricultural waste burning from European countries surrounding the Black Sea was shown for each year during two periods (March–April and July–September). The contribution of biomass burning to the concentrations of EC and OC was shown to be rather small (20 and 14%, respectively, on a yearly basis), although this contribution could be much higher on a monthly basis and showed important seasonal and interannual variability. By removing the biomass burning influence, our data revealed an important seasonal variation of OC, with an increase by almost a factor of two for the spring months of May and June, whereas BC was found to be quite stable throughout the year. Preliminary measurements of Water Soluble Organic Carbon (WSOC) have shown that the monthly mean WSOC/OC ratio remains stable throughout the year (0.45±0.12), suggesting that the partitioning between water soluble and water insoluble organic matter is not significantly affected by biomass burning and secondary organic aerosol (SOA) formation. A chemical mass closure performed in the fine mode (Aerodynamic Diameter, A.D.<1.5μm) showed that the mass contribution of organic matter (POM) was found to be essentially invariable during the year (monthly average of 26±5%).

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EFFECT OF LONG-TERM PIG SLURRY AND SOLID CATTLE MANURE APPLICATION ON SOIL CHEMICAL AND BIOLOGICAL PROPERTIES

Canadian Journal of Soil Science ◽

10.4141/cjss89-005 ◽

1989 ◽

Vol 69 (1) ◽

pp. 39-47 ◽

Cited By ~ 57

Author(s):

A. NDAYEGAMIYE ◽

D. CÔTÉ

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Microbial Activity ◽

Humic Acids ◽

Organic Matter Content ◽

Biological Properties ◽

Matter Content ◽

Cattle Manure ◽

Pig Slurry

Chemical and biological properties were evaluated in 1987 on an acidic silty loam soil following a long-term field study established in 1978 and cultivated with silage corn. Treatments included a control, solid cattle manure (20, 40 and 60 Mg ha−1 FYM) and pig slurry (60, 120 m3 ha−1 SLU) applied every 2 yr and annually, respectively. No fertilizer was applied. The results of this study have shown that neither treatment significantly affected soil pH values, total-N contents and C:N ratios compared to the control. The cation exchange capacity (CEC) of the soil was significantly higher with FYM treatment than with control or SLU application. The highest rates of FYM and SLU have also increased (P < 0.05) soil organic carbon, microbial activity and potentially mineralizable nitrogen. The soil microflora populations (bacteria, fungi, actinomycetes, ammonifiers and nitrifiers) were greatly improved by both treatments. There were no significant differences in organic matter content or the relative amount of humic and fulvic acids between FYM and SLU plots. In spite of these results, FYM application (40 and 60 Mg ha−1) did affect more significantly the distribution of organic carbon in HA and the E4/E6 quotients than SLU additions. Humic acids extracted from SLU amended soils had a lower C content and lower E4/E6 ratios than humic acids from FYM soils. Long-term SLU application did not contribute to decreased organic matter content, CEC and humic acids yield, probably because of optimal organic residues returned to the soil by the corn crops. The FYM application generally improved soil chemical and biological properties. For a sustainable soil productivity, long-term SLU application should then be avoided in rotation in which small amounts of plant residues are returned, especially on soils with low organic matter contents. Key words: Organic matter, microbial activity, nitrogen mineralization potential, CEC, solid cattle manure, pig slurry

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