Divergent Accumulation of Microbial Residues and Amino Sugars in Loess Soil after Six Years of Different Inorganic Nitrogen Enrichment Scenarios

Amino sugars are key microbial biomarkers for determining the contribution of microbial residues in soil organic matter (SOM). However, it remains largely unclear as to what extent inorganic nitrogen (N) fertilization can lead to the significant degradation of SOM in alkaline agricultural soils. A six-year field experiment was conducted from 2013 to 2018 to evaluate the effects of chronic N enrichment on microbial residues, amino sugars, and soil biochemical properties under four nitrogen (urea, 46% N) fertilization scenarios: 0 (no-N, control), 75 (low-N), 225 (medium-N), and 375 (high-N) kg N ha−1. The results showed that chronic N enrichment stimulated microbial residues and amino sugar accumulation over time. The medium-N treatment increased the concentration of muramic acid (15.77%), glucosamine (13.55%), galactosamine (18.84%), bacterial residues (16.88%), fungal residues (11.31%), and total microbial residues (12.57%) compared to the control in 2018; however, these concentrations were comparable to the high-N treatment concentrations. The ratio of glucosamine to galactosamine and of glucosamine to muramic acid decreased over time due to a larger increase in bacterial residues as compared to fungal residues. Microbial biomass, soil organic carbon, and aboveground plant biomass positively correlated with microbial residues and amino sugar components. Chronic N enrichment improved the soil biochemical properties and aboveground plant biomass, which stimulated microbial residues and amino sugar accumulation over time.

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Nitrate fertilization may delay autumn leaf senescence, while amino acid treatments do not

10.1101/2021.11.09.467959 ◽

2021 ◽

Author(s):

Nazeer Fataftah ◽

Erik Edlund ◽

Jenna Lihavainen ◽

Pushan Bag ◽

Lars Björkén ◽

...

Keyword(s):

Inorganic Nitrogen ◽

Soluble Sugar ◽

N Fertilization ◽

Winter Survival ◽

Sugar Accumulation ◽

Molecular Signaling ◽

Delayed Senescence ◽

Fertilization Effect ◽

Autumn Leaf ◽

Autumn Senescence

Fertilization with nitrogen (N)-rich compounds leads to increased growth, but may compromise phenology and winter survival of trees in boreal regions. During autumn, N is remobilized from senescing leaves and stored in other parts of the tree to be used in the next growing season. However, the mechanism behind the N fertilization effect on winter survival is not well understood and it is unclear how N levels or forms modulate autumn senescence. We performed fertilization experiments and showed that treating Populus saplings with high or low levels of inorganic nitrogen resulted in a delay in senescence. In addition, by using precise delivery of solutes into the xylem stream of Populus trees in their natural environment, we found that delay of autumn senescence was dependent on the form of N administered: inorganic N (NO3-1) delayed senescence but amino acids (Arg, Glu, Gln, and Leu) did not. Metabolite profiling of leaves showed that the levels of tricarboxylic acids (TCA), arginine catabolites (ammonium, ornithine), glycine, glycine-serine ratio and overall carbon-to-nitrogen (C/N) ratio were affected differently by the way of applying NO3-1 and Arg treatments. In addition, the onset of senescence did not coincide with soluble sugar accumulation in any of the treatments. Taken together, metabolomic rearrangement under different N forms or experimental setups could modulate senescence process, but not initiation and progression in Populus. We propose that the different regulation of C and N status through direct molecular signaling of NO3-1 could account for the contrasting effects of NO3-1 and Arg on senescence.

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Variation of 13C and 15N enrichments in different plant components of labeled winter wheat (Triticum aestivum L.)

PeerJ ◽

10.7717/peerj.7738 ◽

2019 ◽

Vol 7 ◽

pp. e7738

Author(s):

Zhaoan Sun ◽

Shuxia Wu ◽

Biao Zhu ◽

Yiwen Zhang ◽

Roland Bol ◽

...

Keyword(s):

Triticum Aestivum ◽

Winter Wheat ◽

Grain Filling ◽

Triticum Aestivum L ◽

N Fertilization ◽

Wheat Growth ◽

Filling Stage ◽

N Enrichment ◽

Two Stages ◽

Grain Filling Stage

Information on the homogeneity and distribution of 13carbon (13C) and nitrogen (15N) labeling in winter wheat (Triticum aestivum L.) is limited. We conducted a dual labeling experiment to evaluate the variability of 13C and 15N enrichment in aboveground parts of labeled winter wheat plants. Labeling with 13C and 15N was performed on non-nitrogen fertilized (−N) and nitrogen fertilized (+N, 250 kg N ha−1) plants at the elongation and grain filling stages. Aboveground parts of wheat were destructively sampled at 28 days after labeling. As winter wheat growth progressed, δ13C values of wheat ears increased significantly, whereas those of leaves and stems decreased significantly. At the elongation stage, N addition tended to reduce the aboveground δ13C values through dilution of C uptake. At the two stages, upper (newly developed) leaves were more highly enriched with 13C compared with that of lower (aged) leaves. Variability between individual wheat plants and among pots at the grain filling stage was smaller than that at the elongation stage, especially for the −N treatment. Compared with those of 13C labeling, differences in 15N excess between aboveground components (leaves and stems) under 15N labeling conditions were much smaller. We conclude that non-N fertilization and labeling at the grain filling stage may produce more uniformly 13C-labeled wheat materials, whereas the materials were more highly 13C-enriched at the elongation stage, although the δ13C values were more variable. The 15N-enriched straw tissues via urea fertilization were more uniformly labeled at the grain filling stage compared with that at the elongation stage.

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Divergent responses of biomass accumulation and its allocation to the altered precipitation regimes among different degraded grasslands in China

10.21203/rs.3.rs-243440/v1 ◽

2021 ◽

Author(s):

Tianxue Yang ◽

Junda Chen ◽

Xiaoyue Zhong ◽

Xuechen Yang ◽

Gui Wang ◽

...

Keyword(s):

Climate Models ◽

Plant Biomass ◽

Inorganic Nitrogen ◽

Precipitation Amount ◽

Soil Layer ◽

Ecosystem Functions ◽

Precipitation Frequency ◽

Positive Effects ◽

Altered Precipitation ◽

Precipitation Regimes

Abstract Purpose Climate models predict shifts in precipitation patterns characterized by increased precipitation amount and decreased frequency for semi-arid grasslands in northeast China. However, under these novel climatic conditions, potential differences in plant biomass and its allocation among different degraded grasslands remain unclear.Methods We conducted a mesocosm experiment to test the effects of higher precipitation amount (increased by 50% from the long-term mean) and lower frequency (decreased by 50%) on plant biomass and allocation in the lightly degraded (LDG), moderately degraded (MDG), and severely degraded grasslands (SDG).Results Lower precipitation frequency promoted belowground biomass (BGB), while reducing aboveground biomass (AGB) allocation through enhancing soil water variability. Higher precipitation amount enhanced AGB in LDG and MDG, but not in SDG due to less soil inorganic nitrogen. Lower precipitation frequency weakened the positive effects of higher precipitation amount on biomass. Under altered precipitation, adjustment of AGB vs. BGB allocation was the primary biomass allocation strategy in LDG and SDG. However, to maintain water acquirement, plants in MDG preferred to adjust root vertical distribution, and allocated more roots to the deep soil layer where had a relatively stable water source. This strategy was driven by the changes in plant community composition of the dominant species in MDG.Conclusions The findings of this research emphasized the importance of considering the degradation level of grasslands when predicting the responses of the ecosystem functions to the projected changes in precipitation regime. These findings are critical for making feasible decisions for the sustainable management of degraded grasslands.

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Soil properties after 36 years of N fertilization under continuous corn and corn-soybean management

10.5194/soil-2021-26 ◽

2021 ◽

Author(s):

Nakian Kim ◽

Gevan D. Behnke ◽

María B. Villamil

Keyword(s):

Soil Properties ◽

Crop Rotation ◽

Crop Yields ◽

Inorganic Nitrogen ◽

Block Design ◽

N Fertilization ◽

Total Carbon ◽

Nitrous Oxide Emissions ◽

Continuous Corn

Abstract. Modern agricultural systems rely on inorganic nitrogen (N) fertilization to enhance crop yields, but its overuse may negatively affect soil properties. Our objective was to investigate the effect of long-term N fertilization on key soil properties under continuous corn [Zea mays L.] (CCC) and both the corn (Cs) and soybean [Glycine max L. Merr.] (Sc) phases of a corn-soybean rotation. Research plots were established in 1981 with treatments arranged as a split-plot design in a randomized complete block design with three replications. The main plot was crop rotation (CCC, Cs, and Sc), and the subplots were N fertilizer rates of 0 kg N ha−1 (N0, controls), and 202 kg N ha−1, and 269 kg N ha−1 (N202, and N269, respectively). After 36 years and within the CCC, the yearly addition of N269 compared to unfertilized controls significantly increased cation exchange capacity (CEC, 65 % higher under N269) and acidified the top 15 cm of the soil (pH 4.8 vs. pH 6.5). Soil organic matter (SOM) and total carbon stocks (TCs) were not affected by treatments, yet water aggregate stability (WAS) decreased by 6.7 % within the soybean phase of the CS rotation compared to CCC. Soil bulk density (BD) decreased with increased fertilization by 5 % from N0 to N269. Although ammonium (NH4+) did not differ by treatments, nitrate (NO3−) increased eight-fold with N269 compared to N0, implying increased nitrification. Soils of unfertilized controls under CCC have over twice the available phosphorus level (P) and 40 % more potassium (K) than the soils of fertilized plots (N202 and N269). On average, corn yields increased 60 % with N fertilization compared to N0. Likewise, under N0, rotated corn yielded 45 % more than CCC; the addition of N (N202 and N269) decreased the crop rotation benefit to 17 %. Our results indicated that due to the increased level of corn residues returned to the soil in fertilized systems, long-term N fertilization improved WAS and BD, yet not SOM, at the cost of significant soil acidification and greater risk of N leaching and increased nitrous oxide emissions.

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Effects of nitrogen enrichment on zooplankton biomass and N:P recycling ratios across a DOC gradient in northern-latitude lakes

Hydrobiologia ◽

10.1007/s10750-021-04689-5 ◽

2021 ◽

Author(s):

A.-K. Bergström ◽

A. Deininger ◽

A. Jonsson ◽

J. Karlsson ◽

T. Vrede

Keyword(s):

Community Composition ◽

Resource Use ◽

Phytoplankton Biomass ◽

Phytoplankton Community ◽

N Fertilization ◽

Zooplankton Biomass ◽

Nitrogen Enrichment ◽

C:N:P Stoichiometry ◽

Food Quantity ◽

N Enrichment

AbstractWe used data from whole-lake studies to assess how changes in food quantity (phytoplankton biomass) and quality (phytoplankton community composition, seston C:P and N:P) with N fertilization affect zooplankton biomass, community composition and C:N:P stoichiometry, and their N:P recycling ratio along a gradient in lake DOC concentrations. We found that despite major differences in phytoplankton biomass with DOC (unimodal distributions, especially with N fertilization), no major differences in zooplankton biomass were detectable. Instead, phytoplankton to zooplankton biomass ratios were high, especially at intermediate DOC and after N fertilization, implying low trophic transfer efficiencies. An explanation for the observed low phytoplankton resource use, and biomass responses in zooplankton, was dominance of colony forming chlorophytes of reduced edibility at intermediate lake DOC, combined with reduced phytoplankton mineral quality (enhanced seston N:P) with N fertilization. N fertilization, however, increased zooplankton N:P recycling ratios, with largest impact at low DOC where phytoplankton benefitted from light sufficiently to cause enhanced seston N:P. Our results suggest that although N enrichment and increased phytoplankton biomass do not necessarily increase zooplankton biomass, bottom-up effects may still impact zooplankton and their N:P recycling ratio through promotion of phytoplankton species of low edibility and altered mineral quality.

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Synthesis of Amino Sugars and Amino Sugar Derivatives

Non-Glycolytic Pathways of Metabolism of Glucose ◽

10.1016/b978-0-12-395650-7.50013-0 ◽

1964 ◽

pp. 139-152

Author(s):

SIEGFRIED HOLLMANN

Keyword(s):

Amino Sugar ◽

Amino Sugars ◽

Sugar Derivatives

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Substitution of Inorganic Nitrogen Fertilizer with Green Manure (GM) Increased Yield Stability by Improving C Input and Nitrogen Recovery Efficiency in Rice Based Cropping System

Agronomy ◽

10.3390/agronomy9100609 ◽

2019 ◽

Vol 9 (10) ◽

pp. 609 ◽

Cited By ~ 3

Author(s):

Qaswar ◽

Jing ◽

Ahmed ◽

Shujun ◽

Dongchu ◽

...

Keyword(s):

Crop Yield ◽

Green Manure ◽

Inorganic Nitrogen ◽

Cropping System ◽

N Fertilization ◽

Yield Stability ◽

N Fertilizer ◽

Yield Variability ◽

Variability Index ◽

Double Rice

A long-term field experiment was carried out (since 2008) for evaluating the effects of different substitution rates of inorganic nitrogen (N) fertilizer by green manure (GM) on yield stability and N balance under double rice cropping system. Treatments included, (1) N0 (no N fertilizer and no green manure); (2) N100 (recommended rate of N fertilizer and no green manure); (3) N100-M (recommended rate of N fertilizer and green manure); (4) N80-M (80% of recommended N fertilizer and green manure); (5) N60-M (60% of recommended N fertilizer and green manure); and (6) M (green manure without N fertilization). Results showed that, among all treatments, annual crop yield under N80-M treatment was highest. Crop yield did not show significant differences between N100-M and N80-M treatments. Substitution of different N fertilizer rates by GM reduced the yield variability index. Compared to the N0 treatment, yield variability index of early rice under N100-M, N80-M, and N60-M treatments was decreased by 11%, 26%, and 36%, respectively. Compared to the N0 treatment, yield variability index of late rice was decreased by 12%, 38%, 49%, 47%, and 24% under the N100, N100-M, N80-M, N60-M, and M treatments, respectively. During period of 2009–2013 and 2014–2018, nitrogen recovery efficiency (NRE) was highest under N80-M treatment and N balance was highest under N100 treatment. NRE of all treatments with GM was increased over the time from 2009–2013 to 2014–2018. All treatments with GM showed increasing trend of SOC over the years. Substitution of N fertilizer by GM also increased C inputs and soil C:N ratio compared to the N100 and N0 treatments. Boosted regression model indicated that C input, N uptake and AN were most influencing factors of crop yield. Thus, we concluded that N fertilization rates should be reduced by 20% under GM rotation to attain high yield stability of double rice cropping system through increasing NRE and C inputs.

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Biochar and Its Effects on Plant–Soil Macronutrient Cycling during a Three-Year Field Trial on Sandy Soil with Peppermint (Mentha piperita L.). Part I: Yield and Macro Element Content in Soil and Plant Biomass

Agronomy ◽

10.3390/agronomy10121950 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1950

Author(s):

Urszula Sadowska ◽

Iwona Domagała-Świątkiewicz ◽

Andrzej Żabiński

Keyword(s):

Sandy Soil ◽

Nitrogen Fertilization ◽

Plant Biomass ◽

Biomass Productivity ◽

Crop Productivity ◽

N Fertilization ◽

Mentha Piperita ◽

Plant Soil ◽

Applied Dose ◽

Fertilizer Rates

Pyrolyzed organic residues can be incorporated as a soil additive to improve their properties, crop productivity, or to increase retention or absorption of different compounds. However, in agronomy, the practice of biochar application is still under examination. The interactions between plant, soil, and biochar can be complex, and determines the agronomic effects obtained. A three-year field experiment was conducted to determine the effects of biochar addition and nitrogen (N) fertilization on biomass productivity and nutrient uptake of Mentha piperita L. The experiment was conducted with a three-factorial design in triplicate at N fertilizer rates of 75, 100, and 125 kg N ha−1 and biochar rates of 0, 5, 15, and 45 t ha−1. Commercial wood-based biochar produced at 650 °C was incorporated into sandy soil in 2017. Generally, our results demonstrated potential for treating a sandy soil, since biochar improved the nutrient availability for peppermint. However, on average, during a three-year mint-yielding period, no significant effect of the applied dose of biochar on this parameter was found. Significantly more soluble Ca, K, and SO4-S was found in the soil amended with biochar as compared with the control soil. Biochar, in doses of 15 and 45 t ha−1, increased the NH4-N concentration in the soil in the second and third year of the study, as well as NO3-N in 2018. The greatest amount of N and P was contained in the peppermint biomass after using 15 and 45 t biochar ha−1. The highest dose of biochar (45 t ha−1) also increased the contents of K and S in plants. Nitrogen fertilization increased the dry matter yield of peppermint on the harvest sampling dates. The N content in the mint increased proportionally to the nitrogen dose in fertilization, regardless of the biochar dose applied. The use of biochar in doses of 15 and 45 t ha−1 in coarse-textured soil contributed to increased use of nitrogen by plants after nitrogen fertilization at doses of 100 and 125 kg N ha−1. These findings suggest that the time-dependent responses of soil to biochar amendment are strongly influenced by plant, microbial, and soil feedback; if so, then practical long-term biochar effectiveness requires further study.

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Comprehensive assessment of precursors, diagenesis, and reactivity to water treatment of dissolved and colloidal organic matter

Water Science & Technology Water Supply ◽

10.2166/ws.2004.0054 ◽

2004 ◽

Vol 4 (4) ◽

pp. 1-9 ◽

Cited By ~ 18

Author(s):

J.A. Leenheer

Keyword(s):

Organic Matter ◽

Water Treatment ◽

Condensed Tannins ◽

Drinking Water Treatment ◽

Amino Sugar ◽

Amino Sugars ◽

Research Approach ◽

Soil Aquifer Treatment ◽

Treatment Processes ◽

High Yields

A comprehensive isolation, fractionation, and characterization research approach was developed for dissolved and colloidal organic matter (DOM) in water, and it was applied to various surface- and groundwaters to assess DOM precursors, DOM diagenesis, and DOM reactivity to water treatment processes. Major precursors for natural DOM are amino sugars, condensed tannins, and terpenoids. Amino sugar colloids derived from bacterial cell walls are incompletely removed by drinking water treatment and foul reverse osmosis membranes, but are nearly quantitatively removed by soil/aquifer treatment. When chlorinated, amino sugars produce low yields of regulated disinfection by-products (DBPs) but they produce significant chlorine demand that is likely caused by chlorination of free amino groups. Condensed tannins are major precursors for ,blackwater- DOM such as that found in the Suwannee River. This DOM produces high yields of DBPs upon chorination, and is efficiently removed by coagulation/flocculation treatment. Terpenoid-derived DOM appears to be biologically refractory, infiltrates readily into groundwater with little removal by soil/aquifer treatment, gives low DBP-yields upon chlorination and is poorly removed by coagulation/flocculation treatments. Peptides derived from proteins are major components of the base DOM fraction (10% or less of the mass of DOM), and this fraction produces large yields of haloacetonitriles upon chorination.

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Response of the Illinois Soil Nitrogen Test to liquid and composted dairy manure applications in a corn agroecosystem

Canadian Journal of Soil Science ◽

10.4141/s05-048 ◽

2006 ◽

Vol 86 (4) ◽

pp. 655-663 ◽

Cited By ~ 23

Author(s):

J H Klapwyk ◽

Q M Ketterings ◽

G S Godwin ◽

D. Wang

Keyword(s):

New York ◽

Soil Nitrogen ◽

Nutrient Management ◽

Amino Sugar ◽

Dairy Manure ◽

Corn Yield ◽

Potentially Mineralizable N ◽

Manure Amendments ◽

N Management ◽

Over Time

Dairy manure is important for corn (Zea mays L.) production in New York. Optimizing corn yield while minimizing environmental loss with manure nutrients is often a challenge. A potential tool for improving N management is the Illinois Soil Nitrogen Test (ISNT), which estimates amino sugar N, a pool of potentially mineralizable N for corn uptake. The objectives of this study were to determine (1) the short-term effects of manure applications on ISNT-N, and (2) the longer-term impacts of annual additions of composted and liquid dairy manure on ISNT-N. A 6-wk incubation study showed that NH4-N from manure temporarily (< 2 wk) increased ISNT results. A 4-yr field study was conducted with annual spring applications of two rates of composted dairy manure (45 and 77 Mg ha-1) and two liquid dairy manure rates (63.5 and 180 kL ha-1). Results showed that ISNT-N slightly decreased over time in check plots (no manure or fertilizer additions) and that increases in ISNT-N over time in compost and liquid manure amended plots were consistent with changes in N credits currently given to manures in New York. Our results suggest that the ISNT accounts for N in previously applied compost and manure amendments, but that samples should not be taken within 2-wk following manure addition. Key words: Amino sugar, compost, Illinois Soil Nitrogen Test, nitrogen, manure, nutrient management

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