scholarly journals The changes of soil nitrogen and carbon contents in a long-term field experiment under different systems of nitrogen fertilization

2008 ◽  
Vol 54 (No. 11) ◽  
pp. 463-470 ◽  
Author(s):  
V. Nedvěd ◽  
J. Balík ◽  
J. Černý ◽  
M. Kulhánek ◽  
M. Balíková
Keyword(s):  
Field Experiment ◽  
N Fertilization ◽  
Hot Water ◽  
Control Treatment ◽  
Organic N ◽  
Total N ◽  
C And N ◽  
N Compounds ◽  
Term Field

Content of N and C in soil were investigated in a long-term field experiment under different systems of N fertilization. Chernozem and Cambisol were extracted using hot water (N<sub>hws</sub>, C<sub>hws</sub>) and 0.01M CaCl<sub>2</sub> (N<sub>CaCl2</sub>, C<sub>DOC</sub>). The C<sub>t</sub>/N<sub>t</sub> ratio in Chernozem was 9.6:1 and in Cambisol 6.1:1. The lowest C<sub>t</sub>/N<sub>t</sub> ratio in both experiments was found in the control treatment. Results showed that C and N compounds are less stable in Cambisol, which leads to a higher rate of mineralization. In the Chernozem, N<sub>hws</sub> formed 3.66% from the total N content in the soil whereas N<sub>CaCl2</sub> formed only 0.82%. C<sub>hws</sub> formed 2.98% and C<sub>DOC</sub> 0.34% from total C content. Cambisol contains 4.81% of N<sub>hws</sub> and 0.84% of N<sub>CaCl2</sub> from the total N amount and 5.76% of C<sub>hws</sub> and 0.70% of C<sub>DOC</sub> from the total C content, respectively. Nitrogen extracted by 0.01M CaCl2 formed only 22.4% of N extractable by hot water in Chernozem and 17.5% in Cambisol. The lowest C/N ratios were obtained after the CaCl<sub>2</sub> extraction (3.0–6.2:1). The application of manure increased the content of soil organic N and C compared to the sewage sludge treatments.

scholarly journals Aliphatic compounds, organic C and N and microbial biomass and its activity in long-term field experiment

2011 ◽  
Vol 51 (No. 6) ◽  
pp. 276-282 ◽  
Author(s):  
T. Šimon
Keyword(s):  
Microbial Biomass ◽  
Field Experiment ◽  
Basal Respiration ◽  
Aliphatic Compound ◽  
Hydrophobicity Index ◽  
Organic C ◽  
Aliphatic Compounds ◽  
C And N ◽  
Term Field

The content of aliphatic compounds, hydrophobicity index, organic C and N content and the microbial biomass and respiration activity were analysed in soil samples originating from different plots of a long-term field experiment (variants: nil, NPK &ndash; mineral fertilization: 64.6&ndash;100 kg/ha/year, FYM &ndash; farmyard manure and FYM + NPK) from three blocks (III, IV and B) with different crop rotation. Samples were taken from 0&ndash;200 mm layer in 2002 and 2003 (spring and autumn). The plots without any fertilization had the significantly lowest aliphatic compound content compared to variants fertilized by FYM or FYM + NPK in all the evaluated blocks in both years. The variants fertilized only by mineral NPK without any organic fertilization had the slightly increased aliphatic compound content but they did not exceed significantly the control variants in most cases. The aliphatic compound contents correlated significantly with the organic C contents in 2002 and 2003, as well. The values of the hydrophobicity index showed a similar trend like the data mentioned above. Organic manure increased the soil organic nitrogen content, similarly to the carbon content. In variants fertilized by FYM and FYM + NPK the higher microbial biomass content was found comparing to unfertilized variants. Correlations between aliphatic compound content and biomass differed in spring (2002: r = 0.065, 2003: r = 0.068) and autumn (2002: r = 0.407, 2003: r = 0.529). Organically fertilized variants had increased basal respiration, in autumn 2002 the basal respiration was higher in variants fertilized by mineral NPK, too. The highest specific respiration was recorded in the unfertilised plot in block B (autumn 2002 and 2003), where low microbial biomass exhibited high activity. Increased specific respiration was found also in plots fertilized by FYM and FYM&nbsp;+ NPK (block III and IV, autumn samplings). Positive significant correlations between microbial biomass content and basal respiration were found in 2002 (spring: r = 0.716) and 2003 (spring: r = 0.765, autumn: r = 0.671).

Long-term effects of tillage and nitrogen fertilization on soil C and N fractions in a corn-soybean rotation

2021 ◽  
Author(s):  
Mervin St. Luce ◽  
Noura Ziadi ◽  
Martin H. Chantigny ◽  
Justin Braun
Keyword(s):  
Organic Matter ◽  
N Fertilization ◽  
Interactive Effects ◽  
Long Term Effects ◽  
Total N ◽  
Soil C ◽  
Glycine Max L ◽  
C And N ◽  
N Rates

Tillage and nitrogen (N) fertilization can influence soil organic matter (SOM) dynamics, but their interactive effects remain contradictory. A long-term (25 yr) corn (Zea mays L.)-soybean (Glycine max L. Merr.) rotation was used to investigate the effect of tillage [moldboard plow (MP) and no-till (NT)] and N rates (0, 80 and 160 kg N ha-1) on soil organic carbon (SOC), total N (STN), respiration, and SOM fractions [particulate organic matter (POMC, POMN), mineral-associated organic matter (MAOMC, MAOMN), and microbial biomass (MBC, MBN)]. Results indicate that NT had 27% higher SOC and 24% higher STN than MP in the 0-20 cm depth. Furthermore, SOC and STN stocks (0-20 cm) were 22% and 20% higher, respectively, under NT than MP. There was significant stratification under NT, with a rather uniform distribution under MP. The SOM fractions and soil respiration were 28-275% and 20-83% higher at the 0-5 and 5-10 cm depths, respectively, under NT than MP. Interestingly, N fertilizer rate or its interaction with tillage had no impact, except for respiration (tillage × N rate and N rate × depth). Hence, while N addition was required for adequate grain production and increased cumulative plant C and N inputs, our findings indicate that the vertical distribution of SOC, STN and SOM fractions were affected by tillage, thereby influencing resource accessibility and subsequent dynamics of SOM fractions. Taken together, our results support the adoption of NT and judicious use of N fertilizers for enhancing topsoil SOM storage and fertility under humid temperate conditions.

EFFECT OF FERTILIZER ON SOIL PRODUCTIVITY IN LONG-TERM SPRING WHEAT ROTATIONS

1987 ◽  
Vol 67 (1) ◽  
pp. 165-174 ◽  
Author(s):  
H. H. JANZEN
Keyword(s):  
Organic Matter ◽  
N Fertilization ◽  
N Fertilizer ◽  
Organic N ◽  
Phosphorus Fertilization ◽  
Soil Productivity ◽  
Organic C ◽  
C And N ◽  
N Fertility

Surface soil samples taken from two long-term crop rotations at Lethbridge, Alberta were used to assess the influence of fertilizer N and P on total and mineralizable concentrations of organic C and N in a Dark Brown Chernozemic soil. Rotations sampled were continuous wheat and fallow-wheat-wheat initiated in 1912. In 1967 and 1972, N fertilizer and P fertilizer treatments, respectively, were superimposed over the rotation treatments (which had received no previous fertilizer) to produce a factorial of two N rates (0 and 45 kg N ha−1) by two P rates (0 and 20 kg P ha−1). After 18 yr of application, N fertilizers increased organic C content in both rotations by approximately 14% over that observed in soil receiving no N fertilizer. Organic N contents, similarly, were increased by 15 and 11% in the continuous wheat and fallow-wheat-wheat rotations, respectively. As well, N fertilization increased relative N mineralization potential by 22% in the continuous wheat rotation and by 44% in the fallow-wheat-wheat rotation. Phosphorus fertilization had no significant influence on either total or mineralizable C and N concentrations. Soil pH (measured in dilute CaCl2) was reduced, on average, from 7.2 to 6.9 by 18 annual N applications. These results demonstrate that N fertilization can make significant contributions to the replenishment of organic matter in soil and to the maintenance of indigenous soil N fertility. Key words: Organic matter, nitrogen, carbon, mineralizable nitrogen, mineralizable carbon, pH

scholarly journals Effect of fertilization on the potentially mineralize N forms of soil of long term field experiment was set in an acidic sandy soil

2007 ◽  
pp. 20-24
Author(s):  
Péter Tamás Nagy ◽  
János Lazányi ◽  
Jakab Loch ◽  
Ida Kincses ◽  
Andrea Balláné Kovács
Keyword(s):  
Field Experiment ◽  
Sandy Soil ◽  
Soil Samples ◽  
Organic N ◽  
Biological Interpretation ◽  
Mineralization Processes ◽  
Potentially Mineralizable N ◽  
Set Up ◽  
Term Field

The aim of this paper was to provide further information about the nitrogen mineralization processes of soil. A modified incubation technique was applied to establish the amount of easily soluble mineral and organic N forms during the incubation period. An acidic sandy soil was used for incubation, which was sampled from the „Westsik” long-term field experiment. The incubation was carried out on fifteen selected soil samples which were received different treatments since the experiment was set up. From the obtained results, the amount of potentially mineralizable N and the mineralization rate constant were determined. Results of chemical analysis and biological interpretation of results are discussed.

scholarly journals Effects of two wood-based biochars on the fate of added fertilizer nitrogen—a 15N tracing study

2021 ◽  
Author(s):  
Subin Kalu ◽  
Gboyega Nathaniel Oyekoya ◽  
Per Ambus ◽  
Priit Tammeorg ◽  
Asko Simojoki ◽  
...  
Keyword(s):  
Plant Uptake ◽  
Plant Biomass ◽  
Application Rate ◽  
Control Treatment ◽  
Organic N ◽  
N Leaching ◽  
Soil N ◽  
Mineral N ◽  
Total N ◽  
Application Rates

AbstractA 15N tracing pot experiment was conducted using two types of wood-based biochars: a regular biochar and a Kon-Tiki-produced nutrient-enriched biochar, at two application rates (1% and 5% (w/w)), in addition to a fertilizer only and a control treatment. Ryegrass was sown in pots, all of which except controls received 15N-labelled fertilizer as either 15NH4NO3 or NH415NO3. We quantified the effect of biochar application on soil N2O emissions, as well as the fate of fertilizer-derived ammonium (NH4+) and nitrate (NO3−) in terms of their leaching from the soil, uptake into plant biomass, and recovery in the soil. We found that application of biochars reduced soil mineral N leaching and N2O emissions. Similarly, the higher biochar application rate of 5% significantly increased aboveground ryegrass biomass yield. However, no differences in N2O emissions and ryegrass biomass yields were observed between regular and nutrient-enriched biochar treatments, although mineral N leaching tended to be lower in the nutrient-enriched biochar treatment than in the regular biochar treatment. The 15N analysis revealed that biochar application increased the plant uptake of added nitrate, but reduced the plant uptake of added ammonium compared to the fertilizer only treatment. Thus, the uptake of total N derived from added NH4NO3 fertilizer was not affected by the biochar addition, and cannot explain the increase in plant biomass in biochar treatments. Instead, the increased plant biomass at the higher biochar application rate was attributed to the enhanced uptake of N derived from soil. This suggests that the interactions between biochar and native soil organic N may be important determinants of the availability of soil N to plant growth.

Exploring the Vis-NIR wavelength importance in SOC models under field and lab conditions in a long-term field experiment

2021 ◽  
Author(s):  
Javier Reyes ◽  
Mareike Ließ
Keyword(s):  
Field Experiment ◽  
Spectral Response ◽  
Nir Spectroscopy ◽  
Partial Least Square ◽  
Least Square ◽  
Field Conditions ◽  
Partial Least Square Regression ◽  
Preprocessing Technique ◽  
Term Field

&lt;p&gt;Soil organic carbon (SOC) is of particular interest in the study of agricultural systems as an indicator of soil quality and soil fertility. In the use of Vis-NIR spectroscopy for SOC detection, the interpretation of the spectral response with regards to the importance of individual wavelengths is challenging due to the soil&amp;#8217;s composition of multiple organic and minerals compounds. Under field conditions, additional aspects affect the spectral data compared to lab conditions. This study compared the spectral wavelength importance in partial least square regression (PLSR) models for SOC between field and lab conditions. Surface soil samples were obtained from a long-term field experiment (LTE) with high SOC variability located in the state of Saxony-Anhalt, Germany. Data sets of Vis-NIR spectra were acquired in the lab and field using two spectrometers, respectively. Four different preprocessing methods were applied before building the models. Wavelength importance was observed using variable importance in projection. Differences in wavelength importance were observed depending on the measurement device, measurement condition, and preprocessing technique, although pattern matches were identifiable, especially in the NIR range. It is these pattern matches that aid model interpretation to effectively determine SOC under field conditions.&lt;/p&gt;

Sign in / Sign up

Export Citation Format

Share Document