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.

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.

scholarly journals Variability of Cation-Exchange Capacity (CEC) of Fen Peats in Vertical Profiles from Eastern and Central Poland in Relation to Function of Peatlands as Natural Geological Barriers

2016 ◽  
Vol 33 (2) ◽  
pp. 111-116
Author(s):  
Paweł Rydelek ◽  
Anna Bąkowska ◽  
Piotr Zawrzykraj
Keyword(s):  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Exchange Capacity ◽  
Vertical Profiles ◽  
Central Poland ◽  
Type 3

Abstract An analysis of cation-exchange capacity(CEC) variability of peats is presented in vertical pro files from eastern and central Po land. CEC values were com pared with ash con tent (Ac), pH and CaCO3 content. Eight peatlands were selected for re search in the fol lowingareas: War saw Plateau (2 objects), Siedlce Plateau (2 objects), Lubartów Plateau (2 objects), Nałęczów Table land (1 object) and Dobrohusk Depression (1 object). The peatlands represented a fen peat type of similar botanic compositions of sediments, but they differed in the area, peat thickness and drain age conditions. Characteristic regular i ties in CEC variability were noted in the peatlands and there were three types of CEC variability in vertical pro files. Carbonate peats (types 1 and 2) had the high est pH and definitely the high est values of CEC. In vertical pro files, there was also a zonation, but the regularities similar to non-carbonate peats were not observed. Different distribution of phys i cal and chem i cal parameters were establishedin vertical pro files in partly drained peatlands (with a muck layer on top) with non-carbonate peats (type 3) and there were three distinct zones in vertical pro files, with different Ac and CEC. Determination of the vertical CEC variability and other phys i cal and chem i cal parameters in peatlands made it possible to distinguish zones with potentially most beneficial isolation conditions.

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 A Type 3 Prophage of ‘Candidatus Liberibacter asiaticus’ Carrying a Restriction-Modification System

2018 ◽  
Vol 108 (4) ◽  
pp. 454-461 ◽  
Author(s):  
Zheng Zheng ◽  
Minli Bao ◽  
Fengnian Wu ◽  
Christopher Van Horn ◽  
Jianchi Chen ◽  
...  
Keyword(s):  
Southern China ◽  
Lytic Cycle ◽  
Candidatus Liberibacter Asiaticus ◽  
Specific Pcr ◽  
Candidatus Liberibacter ◽  
Liberibacter Asiaticus ◽  
Type 3 ◽  
Restriction Modification

Prophages, the lysogenic form of bacterial phages, are important genetic entities of ‘Candidatus Liberibacter asiaticus’ (CLas), a nonculturable α-proteobacterium associated with citrus Huanglongbing. Two CLas prophages have been described, SC1 (NC_019549.1, Type 1) and SC2 (NC_019550.1, Type 2), which involve the lytic cycle and the lysogenic cycle, respectively. To explore the prophage repertoire, 523 CLas DNA samples extracted from leaf petioles of CLas-infected citrus were collected from southern China and surveyed for Type 1 and Type 2 prophages by specific PCR. Eighteen samples were found lacking both prophages. One sample, JXGC, sequenced using Illumina HiSeq, generated >100 million short sequence reads (150 bp per read). Read mapping to known prophage sequences showed a sequence coverage of 46% to SC1 and 50% to SC2. BLAST search using SC1 and SC2 as queries identified three contigs from the JXGC de novo assembly that form a circular P-JXGC-3 (31,449 bp), designated as a new Type 3 prophage. Chromosomal integration of P-JXGC-3 was detected to occur within a helicase gene, resulting in a duplication of this gene. P-JXGC-3 had 36 open reading frames (ORFs), 10 of which were not found in Type 1 or Type 2 prophages, including four genes that encoded a restriction-modification (R-M) system (hsdR, hsdS, hsdM1, and hsdM2). Typed by prophage-specific PCR, the CLas strains in southern China contained all combinations of the three prophage types with the exception of a Type 2−Type 3 combination, suggesting active ongoing prophage−phage interactions. Based on gene annotation, P-JXGC-3 is not capable of reproduction via the lytic cycle. The R-M system was speculated to play a role against Type 1 prophage−phage invasion.

EVALUASI PERUBAHAN KUALITAS TANAH PADA LAHAN BEKAS PENAMBANGAN NIKEL DI PULAU GEBE

2018 ◽  
Vol 4 (1) ◽  
Author(s):  
Mardi Wibowo
Keyword(s):  
Organic Carbon ◽  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Exchange Capacity ◽  
Mining Activity ◽  
Evaluation Activity ◽  
Land Quality ◽  
Environment Quality

Since year 1977 until 2005, PT. ANTAM has been exploited nickel ore resources at Gebe Island – Center ofHalmahera District – North Maluku Province. Mining activity, beside give economically advantages also causedegradation of environment quality espicially land quality. Therefore, it need evaluation activity for change ofland quality at Gebe Island after mining activity.From chemical rehabilitation aspect, post mining land and rehabilitation land indacate very lack and lackfertility (base saturated 45,87 – 99,6%; cation exchange capacity 9,43 – 12,43%; Organic Carbon 1,12 –2,31%). From availability of nutrirnt element aspect, post mining land and rehabilitation land indicate verylack and lack fertility (nitrogen 0,1 – 1,19%). Base on that data, it can be concluded that land reclamationactivity not yet achieve standart condition of chemical land.Key words : land quality, post mining lan

FUNCTIONAL STATUS AND ADAPTIVE POTENTIAL IN FOREIGN STUDENTS WITH DIFFERENT TYPES OF VEGETATIVE REGULATION DURING TUITION

2020 ◽  
pp. 118-126
Author(s):  
A.M. Satarkulova
Keyword(s):  
Heart Rate ◽  
Foreign Students ◽  
Autonomic Regulation ◽  
The Body ◽  
Functional Changes ◽  
Different Types ◽  
Type 3 ◽  
Adaptive Abilities

The assessment and dynamic control over students’ status is a very important task. It allows timely detection of prenosological status prior to pathology and health maintenance in students. The objective of the paper is to assess the adaptive abilities of the body, to analyze changes in heart rate variability indicators in students with various types of autonomic regulation, to identify prenosological status and precursory pathological symptoms. Materials and Methods. The study enrolled 302 students from India, aged 21.54±1.43. Programming complex «Psychophysiologist» was used to register the main HRV parameters within 5 minutes. Health status was evaluated according to the index of functional changes and the scale of functional states. Results. N.I. Shlyk (2009) distinguished two groups of students with different types of autonomic regulation: type 1 (53 %) with moderate and type 2 (5 %) with marked characteristics of central regulation profile, type 3 (35 %) with moderate and type 4 (7 %) with marked characteristics of autonomous regulation profile. Main parameters of HRV and adaptation potential were defined for each student.All the parameters characterized functional and health status. Conclusions. It was shown that 82 % of trial subjects (type 1), 53 % (type 2), 94 % (type 3) and 95 % (type 4) demonstrated satisfactory adaptation and their physiological processes were at an optimal level. 18 % of students (type 1) demonstrated reduced adaptive abilities of the body. Moreover, they were under moderate stress. 47 % of subjects (type 2) were also under a significant stress, which was proven by excessively high SI, low SDNN and TP, and an increased index of functional changes. 5 % of students (type 4) revealed dysfunctional characteristics in the heart rhythm, peculiar to pathology. Keywords: foreign students, heart rate variability, types of autonomic regulation, adaptation potential, functional status. Оценка состояния студентов и динамический контроль за ним является важной задачей, поскольку позволяет своевременно выявлять у студентов донозологические состояния, предшествующие патологии, и способствовать сохранению здоровья. Цель. Оценка адаптивных возможностей организма, анализ изменений показателей вариабельности сердечного ритма у студентов с различными типами вегетативной регуляции, выявление донозологических состояний и ранних признаков патологии. Материалы и методы. В исследовании участвовало 302 студента в возрасте 21,54+1,43 года из Индии. Регистрировались основные параметры ВСР в течение 5 мин с использованием программно-аппаратного комплекса «Психофизиолог». Состояние и уровень здоровья оценивались по индексу функциональных изменений и шкале функциональных состояний. Результаты. По способу, предложенному Н.И. Шлык, выделены группы студентов с различными типами вегетативной регуляции: I (53 %) и II типы (5 %) – с умеренным и выраженным преобладанием центрального контура регуляции соответственно, III (35 %) и IV типы (7 %) – с умеренным и выраженным преобладанием автономного контура регуляции соответственно. У каждого из студентов определены основные параметры ВСР и адаптационного потенциала, характеризующие функциональное состояние и уровень здоровья. Выводы. Показано, что для 82 % обследуемых с I типом, 53 % со II типом, 94 % c III типом и 95 % с IV типом регуляции характерно состояние удовлетворительной адаптации, физиологические процессы сохраняются на оптимальном уровне. В группе студентов I типа у 18 % студентов адаптивные возможности организма снижены, выявлено состояние умеренного напряжения. У 47 % обследуемых II типа также зафиксировано состояние резко выраженного напряжения, индикатором которого является чрезмерно высокое значение SI, низкие величины SDNN и ТP, повышенное значение индекса функциональных изменений. В группе студентов с IV типом у 5 % учащихсяв регуляции ритма сердца выявлены дисфункциональные признаки, характерные для патологии. Ключевые слова: иностранные студенты, вариабельность сердечного ритма, типы вегетативной регуляции, адаптационный потенциал, функциональное состояние.

POLIOMYELITIS IN CANADIAN ESKIMOS: LABORATORY STUDIES. V. TYPE 1 AND TYPE 3 POLIOMYELITIS ANTIBODY LEVELS IN BAFFIN ISLAND ESKIMOS

1954 ◽  
Vol 32 (1) ◽  
pp. 119-125
Author(s):  
W. Wood ◽  
Eina M. Clark ◽  
F. T. Shimada ◽  
A. J. Rhodes
Keyword(s):  
Medical Records ◽  
Baffin Island ◽  
Tissue Cultures ◽  
Laboratory Studies ◽  
Poliomyelitis Virus ◽  
Antibody Titers ◽  
Antibody Levels ◽  
Type 3

Studies on the basic immunology of poliomyelitis in Canadian Eskimos have been continued. Some 87 sera collected from Eskimos at Pangnirtung, Baffin Island, have been examined for the presence of Type 1 and Type 3 poliomyelitis antibody by quantitative tests in tissue cultures. The same sera were previously examined for Type 2 antibody by quantitative tests in mice. The results of the three determinations are now presented together for comparison. These sera came from Eskimos aged 2 to 72 years of age. None of the Eskimos showed any evidence of paralysis. Examination of the medical records did not suggest that any paralytic disease had been present in this part of Baffin Island. Very few of the sera showed the presence of poliomyelitis antibody; thus, Type 1 antibody was demonstrated in the sera of 8%, Type 2 antibody in the sera of 9%, and Type 3 antibody in the sera of 14%. No significant number of Eskimos below the age of 45 years had acquired poliomyelitis antibody. The antibody titers mostly ranged between 10−1.0 and 10−2.0, and were significantly lower than the titers customarily found in recently paralyzed cases. These findings suggest that poliomyelitis infection occurred in Pangnirtung Eskimos many years before the date on which the samples were taken (1951). These results point to the worldwide prevalence of the three types of poliomyelitis virus.

scholarly journals Attributes of the soil fertilized with sewage sludge and calcium and magnesium silicate

2015 ◽  
Vol 19 (11) ◽  
pp. 1107-1113 ◽  
Author(s):  
Geraldo R. Zuba Junio ◽  
Regynaldo A. Sampaio ◽  
Altina L. Nascimento ◽  
Luiz A. Fernandes ◽  
Natália N. de Lima ◽  
...  
Keyword(s):  
Sewage Sludge ◽  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Ricinus Communis ◽  
Block Design ◽  
Magnesium Silicate ◽  
Exchange Capacity ◽  
Sludge Compost ◽  
Sewage Sludge Compost ◽  
Randomized Block Design

ABSTRACTThis study aimed to evaluate the chemical attributes of an Inceptisol cultivated with castor bean (Ricinus communis L.), variety ‘BRS Energia’, fertilized with sewage sludge compost and calcium (Ca) and magnesium (Mg) silicate. The experiment was conducted at the ICA/UFMG, in a randomized block design, using a 2 x 4 factorial scheme with three replicates, and the treatments consisted of two doses of Ca-Mg silicate (0 and 1 t ha-1) and four doses of sewage sludge compost (0, 23.81, 47.62 and 71.43 t ha-1, on dry basis). Soil organic matter (OM), pH, sum of bases (SB), effective cation exchange capacity (CEC(t)), total cation exchange capacity (CEC(T)), base saturation (V%) and potential acidity (H + Al) were evaluated. There were no significant interactions between doses of sewage sludge compost and doses of Ca-Mg silicate on soil attributes, and no effect of silicate fertilization on these attributes. However, fertilization with sewage sludge compost promoted reduction in pH and increase in H + Al, OM and CEC. The dose of 71.43 t ha-1 of sewage sludge compost promoted the best soil chemical conditions.

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