scholarly journals Hot-water-soluble Carbon and Surface Properties of Water Repellent Soils

2015 ◽  
Vol 3 (5) ◽  
pp. 165-171 ◽  
Author(s):  
Irena D. Atanassova ◽  
Stefan H. Doerr
Keyword(s):  
Surface Properties ◽  
Water Soluble ◽  
Hot Water ◽  
Water Repellent ◽  
Soluble Carbon

scholarly journals Carbon fraction concentrations in a haplic Luvisol as affected by tillage

2014 ◽  
Vol 60 (No. 6) ◽  
pp. 262-266 ◽  
Author(s):  
J. Horáček ◽  
E. Strosser ◽  
V. Čechová
Keyword(s):  
Cultural Practices ◽  
Fulvic Acids ◽  
Soil Samples ◽  
Water Soluble ◽  
Hot Water ◽  
Protection Measures ◽  
Humus Substances ◽  
Conventional Ct ◽  
Soluble Carbon

Changes of soil organic matter (SOM) parameters were investigated in a haplic Luvisol with medium-heavy texture. Soil samples were taken from several layers at minimum (MT) and conventional (CT) tillage plots of a field experiment in Sitzenhof (Germany). All cultural practices except for tillage (crop rotation, fertilizing, protection measures, etc.) were identical over the whole time of the experiment. The concentrations of oxidizable carbon C<sub>ox</sub> and its constituents (humic acids (HA), fulvic acids (FA), and hot-water soluble carbon) are comparable in layers&nbsp;15&ndash;20 cm in both variants. In 0&ndash;15 cm and 30&ndash;55 cm layers, these concentrations were higher in the MT variant. A similar trend was observed in the colour quotient values of humic substances Q4/6, which indicates increasing condensation of humus substances (HS) at deeper layers in both variants, and it is also confirmed by a humic to fulvic acids ratio HA:FA. Concentrations of SOM fractions were higher (except 15&ndash;20 cm layers) in the MT than CT treatment throughout the profile, especially below the 30 cm depth. The SOM did not accumulate markedly in the surface layer of long-term MT treatment.

scholarly journals A method to determine mineralization kinetics of a decomposable part of soil organic matter in the soil

2011 ◽  
Vol 49 (No. 1) ◽  
pp. 8-11 ◽  
Author(s):  
L. Kolář ◽  
F. Klimeš ◽  
R. Ledvina ◽  
S. Kužel
Keyword(s):  
Organic Matter ◽  
Control System ◽  
Soil Organic Matter ◽  
Oxygen Demand ◽  
Water Soluble ◽  
Hot Water ◽  
Organic Contamination ◽  
Mineralization Kinetics ◽  
Kinetics Of ◽  
Soluble Carbon

A new method was proposed that complements the value of active carbon in the soil expressed as hot-water soluble carbon Chws. The method is based on vacuum measurements of biochemical oxygen demand (BOD) of soil suspensions using an Oxi Top Control system manufactured by the WTW Merck Company that is destined for hydrochemical analyses of organically contaminated waters. Measurements will provide BOD values for particular days of incubation; total limit BODt can be determined from these values, and it is possible to calculate the rate constant k1 of mineralization of a decomposable part of soil organic matter. It is typical of soil organic matter (SOM) of a given soil sample and comparable with the BOD5:COD (chemical oxygen demand) ratio that is used to evaluate degradability of water organic contamination in hydrochemical analytics.

scholarly journals Photodriven Charge Accumulation and Carrier Dynamics in a Water‐Soluble Carbon Nitride Photocatalyst

ChemSusChem ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1728-1736
Author(s):  
Chunyu Li ◽  
Elisabeth Hofmeister ◽  
Igor Krivtsov ◽  
Dariusz Mitoraj ◽  
Christiane Adler ◽  
...  
Keyword(s):  
Carbon Nitride ◽  
Carrier Dynamics ◽  
Water Soluble ◽  
Charge Accumulation ◽  
Soluble Carbon

EXTRACTION OF BORON FROM CSSC REFERENCE SOILS BY HOT WATER, DILUTE CaCl2 AND MANNITOL-CaCl2 SOLUTIONS

1986 ◽  
Vol 66 (2) ◽  
pp. 377-381 ◽  
Author(s):  
P. A. SCHUPPLI
Keyword(s):  
Key Words ◽  
Soil Samples ◽  
Water Soluble ◽  
Hot Water ◽  
Distilled Water ◽  
Background Color ◽  
Color Development ◽  
Reference Soil ◽  
Highly Correlated

Soils were extracted by hot water, dilute CaCl2, and by mannitol-CaCl2 solutions and boron was determined by either azomethine-H or the curcumin method. Results were strongly method dependent; in particular results by the simplest method, mannitol-CaCl2, were generally lower and not highly correlated (r = 0.64) with those by the recommended procedure. This procedure involves extraction with hot distilled H2O (2:1 solution:soil), centrifugation, filtration, color development with azomethine-H and correction for background color. Extractable boron values by this procedure ranged from 0.1 to 1.4 mg kg−1. Background color can be further reduced by the substitution of 0.02 M CaCl2 for distilled water. Key words: CSSC reference soil samples, hot-water-soluble boron

Effect of previous cutting interval and of leaf area remaining after cutting on regrowth of Macroptilium atropurpureum cv. Siratro

1974 ◽  
Vol 14 (68) ◽  
pp. 343 ◽  
Author(s):  
RJ Jones
Keyword(s):  
Leaf Area ◽  
Practical Implication ◽  
Soluble Sugars ◽  
Ground Level ◽  
Fold Increase ◽  
Water Soluble ◽  
Hot Water ◽  
Lag Phase ◽  
Area Index ◽  
Plant Yield

Experiments with Siratro were conducted at Samford, south east Queensland to study the effects of previous cutting and defoliation treatments on regrowth. In the first experiment, swards of Siratro were cut at 7.5 cm above ground level every 4 weeks, every 8 weeks or cut once at 16 weeks during spring and summer. Regrowth of all treatments over ten weeks was measured after varying (by leaf removal) the stubble leaf area index (LAI) of the plots cut every four weeks. Pattern of regrowth yield was similar for all treatments with a pronounced lag phase after cutting. Regrowth yield after 10 weeks differed between treatments and was linearly related (P < 0.01 ) to residual LAI in the stubble at the start of regrowth. In the absence of stubble leaves, plots previously cut at 16 weeks or at 8 weeks yielded marginally more than those cut every 4 weeks. There were no marked treatment differences in gross root morphology other than a two fold increase in stolon rooting for the 16-week treatment. Nitrogen content of the roots (mean 1.38 per cent) was unaffected by treatment, but the per cent hot water soluble sugars were lower for the 16 week defoliation treatment than for the 8-week and the 4-week treatments. In the second experiment individual plants were cut to a uniform stubble every 4 weeks and either 0, 5, or 10 leaves were left. Dry weight of regrowth and stolon development were greatest when most leaves were left. Two thirds of the plants died after six cuttings with complete defoliation but none died when either 5 or 10 leaves were retained. Plant survival was not related to plant yield or degree of stoloniferous development. However, there was a strong correlation between stolon number and plant yield under this intensive cutting regime. The practical implication of the results in the management of Siratro is discussed.

scholarly journals Characteristics of the Water- and Alkali-Soluble Hemicelluloses Fractionated by Sequential Acidification and Graded-Ethanol from Sweet Maize Stems

Molecules ◽  
2019 ◽  
Vol 24 (1) ◽  
pp. 212 ◽  
Author(s):  
Xiaopeng Peng ◽  
Shuangxi Nie ◽  
Xiaoping Li ◽  
Xiong Huang ◽  
Quanzi Li
Keyword(s):  
Potassium Hydroxide ◽  
Ethanol Solution ◽  
Water Soluble ◽  
Hot Water ◽  
Fundamental Information ◽  
Composition And Structure ◽  
Structural Characterizations

Sweet maize stems were treated with hot water and potassium hydroxide to fractionate hemicellulosic polymers. The results showed that the water-soluble hemicelluloses were mainly composed of glucose (27.83%), xylose (27.32%), and galactose (16.81%). In comparison, alkali-soluble hemicelluloses fractionated by acidification and a graded ethanol solution (10%, 20%, 35%, 50%, 65%, and 80%) were mainly composed of xylose (69.73 to 88.62%) and arabinose (5.41 to 16.20%). More highly branched hemicelluloses tended to be precipitated in a higher concentration of ethanol solution, as revealed by the decreasing xylose to arabinose ratio from 16.43 to 4.21. Structural characterizations indicated that alkali-soluble hemicelluloses fractionated from sweet maize stems were mainly arabinoxylans. The results provided fundamental information on hemicelluloses composition and structure and their potential utilization in the fields of biofuels, biochemicals, and biomaterials.

Sign in / Sign up

Export Citation Format

Share Document