CLAY ILLUVIATION IN SOME ORTHIC PODZOLS OF EASTERN CANADA

1965 ◽  
Vol 45 (2) ◽  
pp. 127-138 ◽  
Author(s):  
J. E. Brydon
Keyword(s):  
Organic Matter ◽  
New Brunswick ◽  
Iron Oxides ◽  
Clay Content ◽  
Granular Structure ◽  
Charge Component ◽  
Eastern Canada ◽  
Free Iron ◽  
Fine Clay ◽  
Ph Dependent

The Arago, Barney, and Holmesville soils, Podzols from Quebec, Nova Scotia, and New Brunswick, respectively, each had friable Bfh horizons with moderate granular structure, and with organic matter and free Fe2O3 contents greater than the Ae and C horizons. The Arago and Holmesville had thin Bhft horizons containing over 10% organic matter and 5% free iron oxides. The C horizons of these two soils had some features characteristic of fragipans.The B horizons of the three soils had a high "pH-dependent charge component" in the C.E.C. values. The "permanent charge component" was similar throughout the Arago profile except for the Bhft horizon where clay accumulation had occurred.Translocation of clay from the Ae to the upper B horizons was indicated by the twofold increase in clay content and the relative enrichment of fine clay in the B horizons. Removal of free iron affected the clay contents differently in the different: horizons but the maximum clay content in the upper B horizons remained. The definitions of Orthic Podzols, Textural Podzols, and t horizons should be re-examined.

SOME CATION-EXCHANGE PROPERTIES OF SOILS CONTAINING FREE OXIDES

1964 ◽  
Vol 44 (2) ◽  
pp. 203-211 ◽  
Author(s):  
J. S. Clark
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
New Brunswick ◽  
Cation Exchange ◽  
Iron Oxides ◽  
Extraction Procedure ◽  
Salt Solutions ◽  
Dependent Component ◽  
Ph Dependent ◽  
Exchange Properties

Low C.E.C. values were obtained for the B horizon of a Concretionary Brown soil from British Columbia and a Podzol from New Brunswick, when CaCl2 was used to saturate the cation-exchange complex. Higher CE.C.'s were obtained if Ca(OAc)2 + CaCl2 was used and this showed that the soils had a large pH-dependent component of the C.E.C. Both soils had a high proportion of pH-dependent charge after the destruction of the soil organic matter. Extraction of free iron oxides increased the C.E.C. of the inorganic exchange fractions and eliminated or decreased the pH-dependent component of the C.E.C. Relatively large amounts of iron and aluminum were removed from the soils by the free oxide extraction procedure. These results suggest that the fixation of aluminum and iron was responsible for the low permanent charge values obtained for the soils. The precipitation of the fixed Al and Fe as Al(OH)3 and Fe(OH)3 when the soils were treated with base or extracted with buffered salt solutions released exchange sites and gave an effect equivalent to the release of exchangeable H so that the soils had a large pH-dependent component of the C.E.C.

NATIVE CLAY-FIXED AMMONIUM CONTENT, AND THE FIXATION OF ADDED AMMONIUM OF SOME SOILS OF EASTERN CANADA

1978 ◽  
Vol 58 (1) ◽  
pp. 27-38 ◽  
Author(s):  
F. J. SOWDEN ◽  
G. J. ROSS ◽  
A. A. MacLEAN
Keyword(s):  
New Brunswick ◽  
Clay Mineralogy ◽  
Sandy Soils ◽  
Clay Content ◽  
Lower Percentage ◽  
Slight Effect ◽  
Eastern Canada ◽  
Surface Soils ◽  
Close Relationship ◽  
Cultivated Soils

A study was made of the native clay-fixed NH4+ of some typical soils of Eastern Canada. Usually the amount of fixed NH4+ was related to the clay contents and increased down the profile but there were frequent exceptions to both of these generalizations. The amounts found ranged from 12 to 450 μg fixed NH4+–N/g soil. In general, with some cultivated soils, the cropped areas had lower native fixed NH4+ contents than areas that were in sod. The capacity to fix added NH4+ was usually low in the sandy soils and in general the B and C horizons fixed more NH4+ than the A horizons. For the soils that did fix NH4+, a larger amount but lower percentage was fixed as the amount of added NH4+ was increased. The amount of water in which the NH4+ was added had a slight effect on the percentage fixed, being a little lower as the amount of water was increased. The cultivated New Brunswick surface soils had low NH4+ fixing capacities. Analysis of the clay mineralogy of some soils showed a fairly close relationship between vermiculitic clay content and NH4+ fixation.

CATION EXCHANGE AND ASSOCIATED PROPERTIES OF SOME SOILS FROM VANCOUVER ISLAND, BRITISH COLUMBIA

1967 ◽  
Vol 47 (3) ◽  
pp. 187-202 ◽  
Author(s):  
J. S. Clark ◽  
A. J. Green ◽  
W. E. Nichol
Keyword(s):  
British Columbia ◽  
Organic Matter ◽  
Cation Exchange ◽  
Clay Content ◽  
Vancouver Island ◽  
Southeastern Part ◽  
Ph Dependent ◽  
High Base ◽  
Highly Correlated ◽  
Extractable Al

Studies of the cation exchange properties of the soils of Vancouver Island, British Columbia showed that, in general, the soils had high base saturation even though the precipitation was high. There was no consistent relation between the corrected lime potential values for the soils and the annual precipitation. The pH-dependent CEC values of the soils were highly correlated with organic matter and oxalate-extractable Al but poorer correlations were obtained with the clay content and oxalate-extractable Fe. The correlation between pH-dependent CEC and citrate-dithionite-extractable Fe was not significant. Complexes of Al with organic matter appeared to be the main source of the pH-dependent CEC in the soils.Soils from the drier southeastern part of the Island with fragipans had as low or lower corrected lime potential values in the upper part of the profile than did soils from the more humid and more densely forested parts of the Island. Although oxalate-extractable Al was accumulated in the upper solum of soils with fragipans there was no pronounced enrichment of either oxalate- or citrate-dithionite-extractable Fe. The corrected lime potential pattern and the free oxide distribution of the soils with fragipans differed from the soils without fragipans.

Evidence for genetic hybridization between Ixodes scapularis and Ixodes cookei

2017 ◽  
Vol 95 (8) ◽  
pp. 527-537 ◽  
Author(s):  
James W. Patterson ◽  
Anna M. Duncan ◽  
Kelsey C. McIntyre ◽  
Vett K. Lloyd
Keyword(s):  
Mitochondrial Dna ◽  
Genetic Analysis ◽  
New Brunswick ◽  
Nuclear Dna ◽  
Ixodes Scapularis ◽  
Companion Animals ◽  
Genetic Introgression ◽  
Eastern Canada ◽  
As Species ◽  
Intermediate Traits

Ixodes scapularis Say, 1821 (the black-legged tick) is becoming established in Canada. The northwards expansion of I. scapularis leads to contact between I. scapularis and Ixodes cookei Packard, 1869, a well-established tick species in Eastern Canada. Examination of I. cookei and I. scapularis collected from New Brunswick revealed ticks with ambiguous morphologies, with either a mixture or intermediate traits typical of I. scapularis and I. cookei, including in characteristics typically used as species identifiers. Genetic analysis to determine if these ticks represent hybrids revealed that four had I. cookei derived mitochondrial DNA but I. scapularis nuclear DNA. In one case, the nuclear sequence showed evidence of heterozygosity for I. scapularis and I. cookei sequences, whereas in the others, the nuclear DNA appeared to be entirely derived from I. scapularis. These data strongly suggest genetic hybridization between these two species. Ixodes cookei and hybrid ticks were readily collected from humans and companion animals and specimens infected with Borrelia burgdorferi Johnson et al., 1984, the causative agent of Lyme disease, were identified. These findings raise the issue of genetic introgression of I. scapularis genes into I. cookei and warrant reassessment of the capacity of I. cookei and I. cookei × I. scapularis hybrids to vector Borrelia infection.

Studies of Predators of the Balsam Woolly Aphid, Adelges piceae (Ratz.) (Homoptera: Adelgidae): XI. Cremifania nigrocellulata Cz. (Diptera: Chamaemyiidae), An Introduced Predator in Eastern Canada

1962 ◽  
Vol 94 (11) ◽  
pp. 1171-1175 ◽  
Author(s):  
R. C. Clark ◽  
N. R. Brown
Keyword(s):  
Biological Control ◽  
New Brunswick ◽  
Eastern Canada ◽  
Introduced Predator ◽  
Woolly Aphid ◽  
Commonwealth Institute ◽  
Adelges Piceae ◽  
Research Institute

Cremifania nigrocellulata Cz. is one of the complex of predators that attacks A. piceae (Ratz.) in Europe. After studies on its morphology, biology, and distribution were made by Delucchi and Pschorn-Walcher (1954), C. nigrocellulata was reared in Europe by the Commonwealth Institute of Biological Control and introduced into New Brunswick via the Entomology Research Institute for Biological Control, Belleville, Ontario.

scholarly journals Soil fertility status of some of the intensive crop growing areas under major agroecological zones of Bangladesh

2016 ◽  
Vol 41 (4) ◽  
pp. 735-757 ◽  
Author(s):  
NC Shil ◽  
MA Saleque ◽  
MR Islam ◽  
M Jahiruddin
Keyword(s):  
Organic Matter ◽  
Soil Fertility ◽  
Calcareous Soils ◽  
Clay Content ◽  
Soil Samples ◽  
Exchangeable K ◽  
Low Level ◽  
Fertility Status ◽  
Agroecological Zones ◽  
High Level

Laboratory studies on soil fertility evaluation was carried out across major agroecological zones (AEZs) of Bangladesh to know the nutrient status of soils and to relate those with soil properties like pH, organic matter, CEC, and clay content. Thirty five composite soil samples were collected from intensive crop growing sites, which covered 17 AEZs of Bangladesh. After proper processing, the samples were analyzed for texture, pH, organic carbon, CEC, exchangeable cations (K, Ca, Mg and Na), total N, available P and S following standard methods. The textural class of the soils collected from AEZ 12 and 13 appeared to be mostly clay. Clay loam soil was found in AEZ 4, 8, 9, 11, 25 and 28. Loamy soil was seen in AEZ 1 while AEZ 22, 23 and 29 were mostly sandy textured. The results revealed that 65.7% of the tested soil was acidic while 25.7% was alkaline in nature. All the tested soils showed lower pHKCl compared to pHH2O thus possessed negative charge. About 68.6% of the collected soils contained low (1.10-1.70%) level of organic matter, 25.7% soils retained it at medium level (1.71-2.40) and 5.7% soils at very low level (<1.0%). All the tested soils appeared to be deficient (< 0.12%) in nitrogen content. 68.6% soil samples had the low level of available P while only 8.6% retained it an optimum amount. About 80% of the tested soils contained low level of available S (7.9- 14.7 mg kg -1) although coastal regions soils hold higher amount of available S. High CEC (20-38 cmol kg-1) was found in clay rich soils of AEZ 10, 11, 12, and 13. Study revealed that 40% of the collected soils were very low, 31.4% were low, 8.6% each of medium and optimum, and 11.4% contained high level of exchangeable K. The calcareous soils (AEZ 10, 11, 12 and 13) contained very high level of Ca. Non calcareous soils also showed fairly good level of Ca content except AEZ 1, 3, 23 and 29. Sandy textured soils of greater Dinajpur, Rangpur, Moulvibazar showed lower level of exchangeable Mg. About 86% of the tested soils had the lower (< 2%) potassium saturation percentage (KSP), which needs K application for sustainable crop production. Estimate showed that 44% variability for CEC may be attributed by clay content and the relationship was significant (p = 0.05). Again, 50.4 and 65.6% variability in exchangeable K and Mg, respectively may be governed by clay content of the soils, while such relationship for Ca was non-significant. CEC may contribute 62.2, 92.3 and 83.9% variability for exchangeable K, Ca and Mg content in soils, respectively. The fertility status of most of the studied soils (except AEZ 10, 12, 13 and to some extent 11) appeared to be low to very low, which demand judicious management in order to achieve food security and to conserve the soil fertility.Bangladesh J. Agril. Res. 41(4): 735-757, December 2016

scholarly journals Factors Affecting Microbial Formation of Nitrate-Nitrogen in Soil and Their Effects on Fertilizer Nitrogen Use Efficiency

2001 ◽  
Vol 1 ◽  
pp. 122-129 ◽  
Author(s):  
Alan Olness ◽  
Dian Lopez ◽  
David Archer ◽  
Jason Cordes ◽  
Colin Sweeney ◽  
...  
Keyword(s):  
Organic Matter ◽  
Decision Aid ◽  
Pore Space ◽  
Organic Matter Content ◽  
Clay Content ◽  
Matter Content ◽  
N Fertilizer ◽  
Nitrate N ◽  
Soil Clay ◽  
Soil Clay Content

Mineralization of soil organic matter is governed by predictable factors with nitrate-N as the end product. Crop production interrupts the natural balance, accelerates mineralization of N, and elevates levels of nitrate-N in soil. Six factors determine nitrate-N levels in soils: soil clay content, bulk density, organic matter content, pH, temperature, and rainfall. Maximal rates of N mineralization require an optimal level of air-filled pore space. Optimal air-filled pore space depends on soil clay content, soil organic matter content, soil bulk density, and rainfall. Pore space is partitioned into water- and air-filled space. A maximal rate of nitrate formation occurs at a pH of 6.7 and rather modest mineralization rates occur at pH 5.0 and 8.0. Predictions of the soil nitrate-N concentrations with a relative precision of 1 to 4 μg N g–1of soil were obtained with a computerized N fertilizer decision aid. Grain yields obtained using the N fertilizer decision aid were not measurably different from those using adjacent farmer practices, but N fertilizer use was reduced by >10%. Predicting mineralization in this manner allows optimal N applications to be determined for site-specific soil and weather conditions.

scholarly journals Effect of Botanical Pesticides on Soil Fertility of Coffee-Orchards

2009 ◽  
Vol 9 ◽  
pp. 16-22 ◽  
Author(s):  
Bhanu B. Panthi ◽  
Bhupendra Devkota ◽  
Jyoti U. Devkota
Keyword(s):  
Organic Matter ◽  
Soil Fertility ◽  
Soil Nutrients ◽  
Soil Texture ◽  
Insect Pests ◽  
Clay Content ◽  
High Positive Correlation ◽  
Botanical Pesticides ◽  
Agriculture And Environment ◽  
Commercial Crop

Coffee (Coffea arabica; Rubiaceae) is a potential and emerging commercial crop. Coffee is planted in the midhills of Nepal (800 to 1250 meter above mean sea level) in Gulmi and Lalitpur districts. To control the major insect pests of coffee plant, locally prepared ‘jaibik bishadi’ (botanical pesticides) are used as alternatives of the synthetic insecticides. This study was undertaken to see the contribution of ‘jaibik bishadi’ in the fertility of the coffee orchards soil, for which soil samples from botanicals used and not used coffee orchards were collected to see the level of soil characteristics and soil nutrients such as soil texture, organic matter, soil nutrients (phosphorous and potassium). There was some difference in the soil texture of topsoil, but no difference could be seen in sand, silt and clay content of the subsoils from botanical used and not used orchards. The pH was significantly different between botanical used and not used soils, but such difference could not be observed between the topsoil and subsoil from the same sites. Jaibik bishadi used to control the coffee pests significantly contributed in the soil fertility, which could be seen in high positive correlation (r=0.9886) between organic matter and nitrogen in the soil.Keywords: Coffee, jaibik bishadi, topsoil, subsoil, soil fertilityThe Journal of Agriculture and Environment Vol:9, Jun.2008 page: 16-22

scholarly journals A small rainfall simulator for the determination of soil erodibility.

1987 ◽  
Vol 35 (3) ◽  
pp. 407-415 ◽  
Author(s):  
A. Kamphorst
Keyword(s):  
Organic Matter ◽  
Soil Conservation ◽  
Standard Procedure ◽  
Organic Matter Content ◽  
Clay Content ◽  
Matter Content ◽  
Soil Erodibility ◽  
Rainfall Simulator ◽  
Highly Sensitive

A small rainfall simulator is described, which can be used in the field as well as in the laboratory for the determination of infiltration and erosion characterisitcs of soils. It is particularly suitable for soil conservation surveys, as it is light to carry and easy to handle in the field. A description is given of a standard procedure for the determination of topsoil erodibilities in the field and some results are presented. The method appears to be highly sensitive to soil properties influencing soil erodibility, such as clay content, organic matter content and soil pH. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Relationship between soil oxidizable carbon and physical, chemical and mineralogical properties of umbric ferralsols

2011 ◽  
Vol 35 (1) ◽  
pp. 25-40 ◽  
Author(s):  
Flávio Adriano Marques ◽  
Márcia Regina Calegari ◽  
Pablo Vidal-Torrado ◽  
Peter Buurman
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Clay Content ◽  
Selective Extraction ◽  
Total Carbon ◽  
Soil Matrix ◽  
Soil Variables ◽  
Physical Chemical ◽  
Mineralogical Properties ◽  
Extractable Al

The occurrence of Umbric Ferralsols with thick umbric epipedons (> 100 cm thickness) in humid Tropical and Subtropical areas is a paradox since the processes of organic matter decomposition in these environments are very efficient. Nevertheless, this soil type has been reported in areas in the Southeast and South of Brazil, and at some places in the Northeast. Aspects of the genesis and paleoenvironmental significance of these Ferralsols still need a better understanding. The processes that made the umbric horizons so thick and dark and contributed to the preservation of organic carbon (OC) at considerable depths in these soils are of special interest. In this study, eight Ferralsols with a thick umbric horizon (UF) under different vegetation types were sampled (tropical rain forest, tropical seasonal forest and savanna woodland) and their macromorphological, physical, chemical and mineralogical properties studied to detect soil characteristics that could explain the preservation of high carbon amounts at considerable depths. The studied UF are clayey to very clayey, strongly acidic, dystrophic, and Al-saturated and charcoal fragments are often scattered in the soil matrix. Kaolinites are the main clay minerals in the A and B horizons, followed by abundant gibbsite and hydroxyl-interlayered vermiculite. The latter was only found in UFs derived from basalt rock in the South of the country. Total carbon (TC) ranged from 5 to 101 g kg-1 in the umbric epipedon. Dichromate-oxidizable organic carbon represented nearly 75 % of TC in the thick A horizons, while non-oxidizable C, which includes recalcitrant C (e.g., charcoal), contributed to the remaining 25 % of TC. Carbon contents were not related to most of the inorganic soil variables studied, except for oxalate-extractable Al, which individually explained 69 % (P < 0.001) of the variability of TC in the umbric epipedon. Clay content was not suited as predictor of TC or of the other studied C forms. Bulk density, exchangeable Al3+, Al saturation, ECEC and other parameters obtained by selective extraction were not suitable as predictors of TC and other C forms. Interactions between organic matter and poorly crystalline minerals, as indicated by oxalate-extractable Al, appear to be one of the possible organic matter protection mechanisms of these soils.

Sign in / Sign up

Export Citation Format

Share Document