Ion behavior in plant cell walls. II. Measurement of the Donnan free space, anion-exclusion space, anion-exchange capacity, and cation-exchange capacity in delignified Sphagnum russowii cell walls

1989 ◽  
Vol 67 (2) ◽  
pp. 460-465 ◽  
Author(s):  
Conrad Richter ◽  
Jack Dainty
Keyword(s):  
Cation Exchange ◽  
Anion Exchange ◽  
Free Space ◽  
Cell Walls ◽  
Cation Exchange Capacity ◽  
Dry Weight ◽  
Exchange Capacity ◽  
Anion Exchange Capacity ◽  
Anion Exclusion ◽  
Donnan Free Space

Isolated delignified cell walls from Sphagnum russowii Warnsdorf were incubated in various chloride salt solutions at neutral pH (pH 7 – 8), and ion sorption was measured directly by neutron activation analysis. The anion-exchange capacity was estimated to be 63 – 66 μequiv./g dry weight of wall material in the protonated form. The volume of the anion-exclusion space was 2.63 ± 0.21 (± SD, n = 3) and 1.65 ± 0.35 (± SD, n = 2) mL/g dry weight in NaCl and CaCl2, respectively. A novel approach to measure the Donnan free space is proposed: for walls equilibrated in a salt mixture containing 10 mequiv./L NaCl and 10 mequiv./L CaCl2, the Na+ ions can be considered "uncondensed" in the Manning sense. From the Donnan relationship for Na+ and Cl− ions in the internal and external phases, the Donnan free space was calculated to be 1.77 mL/g dry weight. Titrating walls from pH 2.1 to 9.1 in the presence of 10 mequiv./L NaCl and 10 mequiv./L CaCl2 revealed a maximum cation-exchange capacity above pH 6 of ca. 1900 μequiv./g dry weight. This corresponds to a fixed anionic charge concentration in the Donnan free space of 1.1 M. Key words: ion exchange, cell wall, Donnan free space.

Trifluralin Interactions with Soil Constituents

Weed Science ◽  
1971 ◽  
Vol 19 (1) ◽  
pp. 11-16 ◽  
Author(s):  
R. L. Hollist ◽  
C. L. Foy
Keyword(s):  
Organic Matter ◽  
Cation Exchange ◽  
Surface Area ◽  
Anion Exchange ◽  
Cation Exchange Capacity ◽  
Active Sites ◽  
Foxtail Millet ◽  
Exchange Capacity ◽  
Anion Exchange Capacity ◽  
Nutrient Culture

Concentrations ofα,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine (trifluralin) causing 50% growth reduction (hereinafter referred to as GR50) were determined in nutrient culture and 64 simulated soils using foxtail millet (Setaria italica(L.) Beau.) as an indicator species. The relative order of effectiveness of soil components in reducing trifluralin phytotoxicity was steamed organic matter ≫ organic matter ≫ steamed montomorillonite ≥ steamed kaolinite ≃ kaolinite ≃ montmorillonite. Steaming the organic matter more than doubled the anion exchange capacity. Anion exchange capacity was a better parameter than cation exchange capacity for assessing the potential of an adsorbent to reduce phytotoxicity. Surface area, cation exchange capacity, and adsorption of trifluralin from solution were less reliable indices. The effectiveness of organic matter in reducing phytotoxicity may be due to the exchange capacity and high surface area. Montomorillonite apparently interacted synergistically with other adsorbents to reduce phytotoxicity. Trifluralin did not adsorb on the internal surfaces of montmorillonite as judged by surface area comparisons and X-ray diffraction determinations. Increasing moisture content appeared to block the active sites of trifluralin adsorption. This may be concluded from greater vapor movement and decreased adsorption from a xylene solvent system for moist compared to air dry soils.

scholarly journals Cation exchange capacity of an oxisol amended with an effluent from domestic sewage treatment

2005 ◽  
Vol 62 (6) ◽  
pp. 552-558 ◽  
Author(s):  
Adriel Ferreira da Fonseca ◽  
Luís Reynaldo Ferracciú Alleoni ◽  
Adolpho José Melfi ◽  
Célia Regina Montes
Keyword(s):  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Sewage Treatment ◽  
Barium Chloride ◽  
Dry Weight ◽  
Tropical Soils ◽  
Exchange Capacity ◽  
Strong Positive Correlation ◽  
Ionic Force ◽  
Barium Chloride Solution

The addition of Na-rich anthropogenic residues to tropical soils has stimulated the scientific community to study the role of sodium in both the soil solution and the exchange complex. In this study, several different methods were used to calculate the concentration of exchangeable and soluble cations and this data was then used to establish correlations between the level of these cations and both the accumulation of various elements and the dry weight of maize grown in a greenhouse under different conditions. In the closed environments of the pots, the most suitable method for calculating the effective cation exchange capacity (ECEC) was the cation exchange capacity calculated by cations removed with barium chloride solution (CEC S). Then again, the actual cation exchange capacity (CEC A) should be measured by using Mg adsorption to prevent ionic force from influencing electric charges. A strong positive correlation was obtained between the concentrations of Na in the 1:2 soil:water extracts and the accumulation of Na in the maize plants, indicating saline or double acid extractors are not needed when monitoring the Na concentration only.

Chemical fertility of krasnozems - a review

Soil Research ◽  
1994 ◽  
Vol 32 (5) ◽  
pp. 1015
Author(s):  
PW Moody
Keyword(s):  
Organic Matter ◽  
Cation Exchange ◽  
Anion Exchange ◽  
Cation Exchange Capacity ◽  
Clay Fraction ◽  
Exchange Capacity ◽  
Published Data ◽  
Total N ◽  
Eastern Australia ◽  
Ph Buffer

Krasnozems (Ferrosols) characteristically have high contents of citrate-dithionite extractable Fe and moderate to high contents of clay throughout the profile. They typically have low cation exchange capacity (2-20 cmolc kg-1), high P sorbing ability, and a significant anion exchange capacity at depth. The chemistry of krasnozems is dominated by the variable charge characteristics of the organic matter and the oxy-hydroxides of Fe and Al which occur in the predominantly kaolinitic clay fraction. The effects of surface charge characteristics, organic matter, and extractable iron and aluminium on the cation and anion exchange capacities, P sorbing abilities and pH buffer capacities of Australian krasnozems are reviewed. A selection of reports of nutrient deficiencies and toxicities in these soils is presented and briefly discussed. Published data on the chemical composition of the soil solutions of krasnozems are reviewed. Data from a suite of paired (undeveloped and developed) krasnozem profiles from eastern Australia indicate that exchangeable Ca and Mg, effective cation exchange capacity (ECEC), pH buffer capacity (pHBC) and total N decrease significantly (P < 0.05) in the A horizon following development, while exchangeable K, ECEC and pHBC decrease (P < 0-05) in the B horizon. The decreases in the A horizon are shown to be a direct consequence of the decline in organic matter which occurs following development. Because of the crucial role that organic matter plays in the chemical fertility of krasnozems, they are less likely to maintain their fertility under exploitative conditions than other productive clay soils such as Vertosols. It is concluded that the sustainable use of krasnozems will depend on maintenance or enhancement of organic matter levels, maintenance of surface and subsoil pH by regular application of amendments, minimization of erosion, and replacement of nutrients removed in harvested products.

The grouping of soils with similar charge properties as a basis for agrotechnology transfer

Soil Research ◽  
1987 ◽  
Vol 25 (3) ◽  
pp. 275 ◽  
Author(s):  
GP Gillman ◽  
DF Sinclair
Keyword(s):  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Southern China ◽  
Exchange Capacity ◽  
Eastern United States ◽  
Anion Exchange Capacity ◽  
Basic Cation ◽  
Type 3

A set of 94 variable charge soils (Oxisols and Ultisols) from humid tropical Queensland has been formed into three groups on the basis of their surface charge characteristics. Mean curves of basic cation exchange capacity (CECB) against pH, total cation exchange capacity (CECT) against pH, and anion exchange capacity (AEC) against pH for each group at various soil depths were derived, to describe the essential features of each group, designated as Type 1, Type 2 and Type 3 soils. Type 1 soils have high CEC and low AEC, Type 2 soils have low CEC and low AEC, and Type 3 soils have low CEC and high AEC. A number of statistical devices were employed to illustrate the clear separation of the three groups. Additional Oxisol and Ultisol soils from southern China, Peru and the south-eastern United States were successfully allocated to our three groups, but this was not possible for some Andisols from Papua New Guinea. Aspects of possible different management requirements of each group are discussed.

scholarly journals The Location of the Donnan Free Space in Disks of Beetroot Tissue

1965 ◽  
Vol 18 (3) ◽  
pp. 547 ◽  
Author(s):  
MG Pitman
Keyword(s):  
Cation Exchange ◽  
Free Space ◽  
Cell Walls ◽  
Donnan Free Space

This paper describes experiments which show that the cell walls of beetroot tissue contain sufficient cation�exchange sites to account for at least 95% of the Donnan free space (D.F.S.) as measured by Briggs, Hope, and Pitman (1958). The contribution of the cytoplasm to the D.F.S. in their measurements was therefore less than 5%. The exchange sites in the D.F.S. of the tissue and in the cell walls have the same pKa of about 2�8, and are considered to be due to bound Ilronic acids.

Biosynthèse des pectines et différenciation des fibres cellulosiques au cours de la croissance du lin

1989 ◽  
Vol 67 (1) ◽  
pp. 135-139 ◽  
Author(s):  
O. Morvan ◽  
A. Jauneau ◽  
C. Morvan ◽  
H. Voreux ◽  
M. Demarty
Keyword(s):  
Cell Wall ◽  
Cation Exchange ◽  
Cell Walls ◽  
Cation Exchange Capacity ◽  
Stem Elongation ◽  
Exchange Capacity ◽  
Pectin Content ◽  
Cellulose Deposition ◽  
Cellulosic Fibres ◽  
Elongation Phase

During the first stage of flax growth, stem elongation reaches 2.4 cm per day and the percentage of cell wall remains quite constant (4–15%). Cellulosic fibres develop principally during capsule formation and seed maturation. During the latter stage, the proportion of walls increases from 15 to 60% and the elongation is diminished to 0.5 cm per day. The lowering of the cation exchange capacity and of the pectin content of the cell walls during growth results principally from increased cellulose deposition in the fibre cells. The changes in the cation exchange capacity and in the percentage of cell wall show that when cellulose biosynthesis predominates, there is a continuous synthesis of pectins (10–15%) during the development of the plant. Methylated pectins are synthesized during the elongation phase. During maturation, the relative amounts of highly and less methylated pectins remain the same and thus it is not possible to determine what type of pectin is preferentially synthesized.

Cation-exchange capacity of plant cell walls at neutral pH

1985 ◽  
Vol 36 (11) ◽  
pp. 1065-1072 ◽  
Author(s):  
Michael S. Allen ◽  
Michael I. McBurney ◽  
Peter J. Van Soest
Keyword(s):  
Cation Exchange ◽  
Plant Cell ◽  
Cell Walls ◽  
Cation Exchange Capacity ◽  
Exchange Capacity ◽  
Plant Cell Walls ◽  
Neutral Ph

Corrigenda - Chemical fertility of krasnozems - a review

Soil Research ◽  
1994 ◽  
Vol 32 (5) ◽  
pp. 1015
Author(s):  
PW Moody
Keyword(s):  
Organic Matter ◽  
Cation Exchange ◽  
Anion Exchange ◽  
Cation Exchange Capacity ◽  
Clay Fraction ◽  
Exchange Capacity ◽  
Published Data ◽  
Total N ◽  
Eastern Australia ◽  
Ph Buffer

Krasnozems (Ferrosols) characteristically have high contents of citrate-dithionite extractable Fe and moderate to high contents of clay throughout the profile. They typically have low cation exchange capacity (2-20 cmolc kg-1), high P sorbing ability, and a significant anion exchange capacity at depth. The chemistry of krasnozems is dominated by the variable charge characteristics of the organic matter and the oxy-hydroxides of Fe and Al which occur in the predominantly kaolinitic clay fraction. The effects of surface charge characteristics, organic matter, and extractable iron and aluminium on the cation and anion exchange capacities, P sorbing abilities and pH buffer capacities of Australian krasnozems are reviewed. A selection of reports of nutrient deficiencies and toxicities in these soils is presented and briefly discussed. Published data on the chemical composition of the soil solutions of krasnozems are reviewed. Data from a suite of paired (undeveloped and developed) krasnozem profiles from eastern Australia indicate that exchangeable Ca and Mg, effective cation exchange capacity (ECEC), pH buffer capacity (pHBC) and total N decrease significantly (P < 0.05) in the A horizon following development, while exchangeable K, ECEC and pHBC decrease (P < 0-05) in the B horizon. The decreases in the A horizon are shown to be a direct consequence of the decline in organic matter which occurs following development. Because of the crucial role that organic matter plays in the chemical fertility of krasnozems, they are less likely to maintain their fertility under exploitative conditions than other productive clay soils such as Vertosols. It is concluded that the sustainable use of krasnozems will depend on maintenance or enhancement of organic matter levels, maintenance of surface and subsoil pH by regular application of amendments, minimization of erosion, and replacement of nutrients removed in harvested products.

Measurement of Cation Exchange Capacity (CEC) of Plant Cell Walls by X-Ray Microanalysis (EDX) in the Transmission Electron Microscope

2007 ◽  
Vol 13 (4) ◽  
pp. 233-244 ◽  
Author(s):  
Eberhard Fritz
Keyword(s):  
Electron Microscope ◽  
Cation Exchange ◽  
Plant Cell ◽  
Transmission Electron Microscope ◽  
Cell Walls ◽  
Cation Exchange Capacity ◽  
Exchange Capacity ◽  
Root Tissue ◽  
Plant Cell Walls ◽  
Transmission Electron

Cation exchange capacity (CEC) characterizes the number of fixed negative charges of plant cell walls and is an important parameter in studies dealing with the uptake of ions into plant tissues, especially in roots. Conventional methods of CEC determination use bulk tissue, the results are the mean of many cells, and differences in the CEC of different tissue types are masked. Energy-dispersive microanalysis (EDX) in the transmission electron microscope allows CEC determinations on much finer scales. Shoot and fine root tissue ofPicea abieswas acid washed to remove exchangeable cations. Tissue blocks or semithin tissue sections were loaded with 0.2 mM CaCl2, AlCl3, or Pb(NO3)2at pH 4.0. The amount of Ca, Al, or Pb adsorbed to the exchange sites of cell walls was determined by EDX. The CEC of cell walls of different tissue types was highly different, ranging in shoot tissues from 0 to 856 mM Ca and 5.8 to 1463 mM Al (block loading) or 4.3 to 1116 mM Ca and 0 to 2830 mM Al (section loading). In root tissue, Pb adsorption to semithin sections yielded CEC values between 29.1 and 954 mM Pb. In mostP. abiesshoot tissues, the binding capacity was clearly higher for Al than for Ca.

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