Kinetics of acid phosphatase in calcium chloride extractable soil organic matter

2008 ◽  
Vol 40 (9) ◽  
pp. 2076-2078 ◽  
Author(s):  
S. Marinari ◽  
G. Masciandaro ◽  
B. Ceccanti ◽  
S. Grego
Keyword(s):  
Organic Matter ◽  
Acid Phosphatase ◽  
Soil Organic Matter ◽  
Calcium Chloride ◽  
Kinetics Of ◽  
Extractable Soil

ASSESSMENT OF AVAILABLE SOIL SULPHUR IN AN 35S GROWTH CHAMBER EXPERIMENT

1974 ◽  
Vol 54 (3) ◽  
pp. 309-315 ◽  
Author(s):  
J. R. BETTANY ◽  
J. W. B. STEWART ◽  
E. H. HALSTEAD
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Growth Chamber ◽  
Yield Response ◽  
Laboratory Studies ◽  
Organic S ◽  
Chamber Experiment ◽  
Extractable Soil

Growth chamber and laboratory studies of four selected soils differing in C:N:S ratios and the percentage of total S present as HI-reducible S in the soil organic matter showed that: (1) the yield response of alfalfa to applied S occurred when the 0.01 M CaCl2-extractable soil SO4—S was less than 3.3 μg/g, (2) mineralization of soil organic S was unaffected by the addition of 25 μg S/g to the soils, and (3) the amount of S mineralized was not directly related to the quantity of total S, HI-S or the percentage of total S present as Hi-reducible S. It was noted that the largest amount of S mineralized occurred from the soil with the lowest C:N:S ratios.

scholarly journals Microbiological properties and oxidizable organic carbon fractions of an oxisol under coffee with split phosphorus applications and irrigation regimes

2013 ◽  
Vol 37 (1) ◽  
pp. 55-65 ◽  
Author(s):  
Adriana Rodolfo da Costa ◽  
Juliana Hiromi Sato ◽  
Maria Lucrécia Gerosa Ramos ◽  
Cícero Célio de Figueiredo ◽  
Géssica Pereira de Souza ◽  
...  
Keyword(s):  
Organic Matter ◽  
Acid Phosphatase ◽  
Soil Organic Matter ◽  
Organic Carbon ◽  
Microbial Biomass Carbon ◽  
Block Design ◽  
Phosphorus Fertilization ◽  
Carbon Fractions ◽  
Irrigation Regimes ◽  
Organic Carbon Fractions

Phosphorus fertilization and irrigation increase coffee production, but little is known about the effect of these practices on soil organic matter and soil microbiota in the Cerrado. The objective of this study was to evaluate the microbiological and oxidizable organic carbon fractions of a dystrophic Red Latossol under coffee and split phosphorus (P) applications and different irrigation regimes. The experiment was arranged in a randomized block design in a 3 x 2 factorial design with three split P applications (P1: 300 kg ha-1 P2O5, recommended for the crop year, of which two thirds were applied in September and the third part in December; P2: 600 kg ha-1 P2O5, applied at planting and then every two years, and P3: 1,800 kg ha-1 P2O5, the requirement for six years, applied at once at planting), two irrigation regimes (rainfed and year-round irrigation), with three replications. The layers 0-5 and 5-10 cm were sampled to determine microbial biomass carbon (MBC), basal respiration (BR), enzyme activity of acid phosphatase, the oxidizable organic carbon fractions (F1, F2, F3, and F4), and total organic carbon (TOC). The irrigation regimes increased the levels of MBC, microbial activity and acid phosphatase, TOC and oxidizable fractions of soil organic matter under coffee. In general, the form of dividing P had little influence on the soil microbial properties and OC. Only P3 under irrigation increased the levels of MBC and acid phosphatase activity.

Alkali-extractable soil organic matter: An important factor affecting the mycelial growth of ectomycorrhizal fungi

2008 ◽  
Vol 40 (1) ◽  
pp. 37-43 ◽  
Author(s):  
L. Soukupová ◽  
H. Hršelová ◽  
H. Gryndlerová ◽  
V. Merhautová ◽  
M. Gryndler
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Ectomycorrhizal Fungi ◽  
Mycelial Growth ◽  
Extractable Soil

Influence of water molecule bridges on sequestration of phenol in soil organic matter of sapric histosol

2019 ◽  
Vol 16 (7) ◽  
pp. 541 ◽  
Author(s):  
Pavel Ondruch ◽  
Jiri Kucerik ◽  
Daniel Tunega ◽  
Nadeesha J. Silva ◽  
Adelia J. A. Aquino ◽  
...  
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Water Molecule ◽  
Organic Molecules ◽  
Desorption Kinetics ◽  
Modulated Differential Scanning Calorimetry ◽  
Time Constants ◽  
Oh Groups ◽  
Solvation Energies ◽  
Kinetics Of

Environmental contextImmobilisation of organic chemicals in soil organic matter can strongly influence their availability in the environment. We show that the presence of water clusters, called water molecule bridges, hampers the release of organic molecules from soil organic matter. Moreover, water molecule bridges are sensitive to changes in environmental conditions (e.g., temperature or moisture) which affect the release of organic molecules into the environment. AbstractWater molecule bridges (WaMB) can stabilise the supramolecular structure of soil organic matter (SOM) by connecting individual SOM molecular units. WaMB are hypothesised to act as a desorption barrier and thus to physically immobilise molecules in SOM. To test this hypothesis, we prepared two sets of soil samples – aged samples with WaMB developed, and vacuumed samples, in which WaMB were disrupted. The samples were spiked with phenol and then stored under controlled humidity. The degree of phenol immobilisation in SOM was assessed by desorption kinetics of phenol into a gas phase. This was compared with the thermal stability (T*) of WaMB obtained by modulated differential scanning calorimetry (MDSC) and the results were related to computer modelling, which provided the stability and solvation energies of phenol-WaMB-SOM models. The desorption kinetics of phenol was best described by a first-order model with two time constants ranging between 1 and 10h. In aged samples, the time constants correlated with T*, which showed that the desorption time increased with increasing WaMB stability. Molecular modelling proposed that phenol molecules are preferentially locked in nanovoids with polar OH groups pointed to WaMB in the most stable configurations. Both findings support the hypothesis that WaMB can act as a desorption barrier for phenol.

scholarly journals Enzyme activities of urban soils under different land use in the Shenzhen city, China

2008 ◽  
Vol 54 (No. 8) ◽  
pp. 341-346 ◽  
Author(s):  
Z.J. Shi ◽  
Y. Lu ◽  
Z.G. Xu ◽  
S.L. Fu
Keyword(s):  
Organic Matter ◽  
Acid Phosphatase ◽  
Soil Organic Matter ◽  
Direct Effect ◽  
Soil Ph ◽  
Soil Enzymes ◽  
Urban Soils ◽  
Urban Park ◽  
Shenzhen City ◽  
Positive Direct

Urbanization has drastically changed soil properties, and an assessment of these changes is essential for soil management and soil health. The activities of urease, acid phosphatase, invertase and catalase, soil organic matter, pH, electrical conductivity (EC) and clay (< 0.01 mm) content of urban soils under two land-uses in the central built-up area of the Shenzhen city were investigated, and multivariate analysis was used to study the relationship between soil enzymes and soil physical-chemical properties. The results showed that invertase activity in roadside soil was significantly higher than that in urban park soil, whereas catalase activity was significantly higher in urban park soil. Soil organic matter had significant positive correlation with activities of invertase, urease and acid phosphatase but not with catalase. Soil pH had a significant negative direct effect on urease and acid phosphatase activity, but the effect was counteracted by positive indirect effect of soil organic matter. Soil EC had a positive direct effect on activities of catalase and there was a significant correlation between soil EC and soil catalase activities. Soil organic matter, soil pH and EC were the major factors influencing activities of soil enzymes.

Sign in / Sign up

Export Citation Format

Share Document