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Artigo Acesso aberto

Florence Annie Mockeridge,

... that the presence of a certain amount of humus in soil is essential to complete fertility, and ... fresh. This has been attributed to the soluble humus formed during the rotting, but wherein lies the peculiar merit of this soluble humus has long been a debatable point, some considering ... well known that raw peat, although rich in humus, is practically useless as a manure, on account of its acid and insoluble nature. This insoluble humus can be neutralised and rendered largely soluble by ... almost all experiments on the effect of soluble humus on bacteria have hitherto been carried out with ...

Tópico(s): Peatlands and Wetlands Ecology

1917 - Royal Society | Proceedings of the Royal Society of London Series B Containing Papers of a Biological Character

Periodico Acesso aberto

Periódicos nacionais

Jornais Acesso aberto

Ernest Newman, Stephen Gwynn, A. B., James McDOWALL "Sunday Times" Special Correspondent, W. W. H., A. J. Temple, H. H., A. T. Johnson, Ernest A. Lbblewhite, C. Williams Wood, R. Harrison, Wyndham Deedes, Floyd S. Chalmers "Sunday Times" Special Correspondent, Capt Russell Grenfell "Sunday Times" Naval Correspondent, Stanley G. R. Holman, Walter Lippmann, Yarborough, W. Kay Robinson, Sir John Russell F. R. S., Ralph Straus, George Chambers, E. G. Farrow, (The Rev.) P. R. Harvey, R. W. Cilento, Bryan Pontifex, S. M. Collins, Eric Newton, Norman Crump City Editor, Iain Lang, James Agate, H. L. L. Denny, Julia Herrick, R. H., E. L. Bowley, K. H. Davison, D. R. Gent, Lord Rennell, Sir Howard Kelly, G. L. Schwartz, H. G. Occomore Headmaster, G. J. Marson, Frank MacDermot Special Correspondent of "The Sunday Times", Harold Robson, G. Leveson Gower, D McFairlane, W. L. Portsmouth, A. McLeod, (Rev.) D. Stedman Davies, the Rev S. M. Berry D. D., Sir Eric Phipps H. M. Minister, Arthur C. Wardle, Arthur MacHen, Dilys Powell, Alexander Werth Special Correspondent of "The Sunday Times", George Mills, H. H. Gairdner, W. T. Stuttard Special Correspondent of "The Sunday Times", Harold M. Abrahams, William Courtenay "Sunday Times" Special Correspondent, Professor V. de Sola Pinto, Laelius, E. L. Cohrane, W. G. Corp, A. P. Wells, O. H. Brandon "Sunday Times" Special Correspondent, Alan H. Brodrick,

... Darton & Co., Ltd. A Darwin Discovery Darwin on Humus and the Earthworm. (Faber. 8s. 6d.) New Novels ...

1945 - Gale Group | Sunday Times HA GDA

Artigo

R. J. Swaby,

Summary S everal methods were used for extracting humus from a number of widely different soil types. ... cements were rapidly restored; chernozems containing much colloidal humus and clay took longer, but other types showed ... after prolonged treatment. Sterilization of soil rendered the humus more available for micro‐organisms, which were then ... humate. This paper examines the possibility of colloidal humus constituents acting as soil cements. Geltsef (1936, 1937, ... physical condition of soil. She considers that resistant humus is practically inert and plays little part in ...

Tópico(s): Turfgrass Adaptation and Management

1950 - Wiley | Journal of Soil Science

Artigo

AE Martin, Ronald C. Reeve,

... carbon/aluminium ratio on the flocculation of podzol humus by aluminium is reported. Portions of resin‐treated humus extracts were adjusted to selected pH values (which ... C/Al ratios of 16, using B‐horizon humus from an Australian podzol, complete precipitation of C ... Al ratio of 16, only partial precipitation of humus and Al occurred which was maximal at pH 2·5. Similar results were obtained for humus from a New Zealand podzol although it was ... of C/Al ratio, degree of flocculation, or humus type, but which depended on the mean pH ...

Tópico(s): Mine drainage and remediation techniques

1960 - Wiley | Journal of Soil Science

Artigo Acesso aberto

AE Martin,

Summary Resin‐treated humus extracts, adjusted to predetermined pH values, were mixed with solutions of FeCl 3 , FeCl 2 , or NiCl 2 , at ... ratios of 3 and 6, maximum precipitation of humus and Fe occurred at pH 2‐3, i. ... pH of hydrous ferric oxide. Above pH 3, humus was almost completely dispersed; Fe was partially precipitated at pH 5 without extensive co‐precipitation of humus. At ratios of C to Fe(III) found ... podzol (C/Fe(III) = 22), no flocculation of humus occurred at any pH value from 1 to ... C/Fe(III) = 5·8) complete flocculation of humus occurred from pH 1·8 to pH 4. ...

Tópico(s): Environmental Toxicology and Ecotoxicology

1960 - Wiley | Journal of Soil Science

Jornais Acesso aberto

Wm. Power,

... Stock Sale, Johannesburg's Waste Johannesburg, March 23, Humus in the Soll, Buying Seeds, Major Griffiths London, ...

1908 - Gale Group | NCCO EuropeAfrica

Artigo

Beryl C. Barratt,

Summary The humus form is recognized in a soil profile as the group of A horizons in which organic matter is ... thus the upper part only of the genetic humus type, the true measure of which is the ... profile extending into B and C horizons. Grassland humus forms are subdivided on a basis of field ... residues are largely incorporated as an intimate clay‐humus mixture, and mor, in which organic residues in ... variation in horizon thickness, structure, and consistence, sixteen humus forms are recognized: strongly granular, weakly granular, massive ...

Tópico(s): Soil Carbon and Nitrogen Dynamics

1964 - Wiley | Journal of Soil Science

Jornais Acesso aberto

... Jurymen Indignant, The Burglar's Escape, Peas as Humus, A New Evil Stock Disease, Royal Visitor to ...

1907 - Gale Group | NCCO EuropeAfrica

Artigo Acesso aberto Revisado por pares

Sadao Shoji, Masahiko Saigusa,

... silica, or these minerals and allophane in the humus horizons, and allophane in the non-humus ones. Towada-b soils overlain by the Towada- ... of the main clay minerals in all the humus horizons as well as non-humus ones. The main clay minerals of Chuseri soils ... chiefly of chloritic intergrades and chlorite in the humus horizons, and allophane in the non-humus ones. Opaline silica was present in minor amounts in the humus horizons of Chuseri soils, but nearly absent in ... Were dominant in the clay fractions of both humus and non-humus horizons of very shallowly buried ...

Tópico(s): Iron oxide chemistry and applications

1977 - Taylor & Francis | Soil Science & Plant Nutrition

Artigo Revisado por pares

George Nakos,

... of urea or NH 4 NO 3 with humus from stands of fir ( Abies cephalonica , Loudon) growing ... developed from flysch (shales) and limestone and with humus from stands of black pine ( pinus nigra , Arn.) ... from peridotites, limestone and schists were investigated. Fir humus from stands on flysch and limestone and black pine humus from limestone showed nitrification but it was absent from black pine humus from stands on peridotites and on schists. Humus from stands on schists showed appreciable ammonification. Increasing ...

Tópico(s): Phosphorus and nutrient management

1976 - Elsevier BV | Soil Biology and Biochemistry

Artigo Revisado por pares

Sadao Shoji, Yasushi Fujiwara,

... significance of active Al and Fe in the humus horizons of Andosols from northeastern Japan and formed ... layer silicates and in minor amounts in Al-humus complex. The Fe of weathering products, however, consisted ... the "free"form, which is largely complexed with humus. A small portion of this element was contained ... in small amounts in allophanelike constituents and Al-humus. The Fe of weathering products in these soils ... of "free" Fe, which is partly complexed with humus. We indicated that the formation of Al- and ...

Tópico(s): Geology and Paleoclimatology Research

1984 - Lippincott Williams & Wilkins | Soil Science

Artigo Revisado por pares

Sadao Shoji, Toyoaki Ito, Masahiko Saigusa, Ichiro Yamada,

... allophanic Andosols in Japan: (1) very dark, thick humus horizons, (2) granular structure in the humus horizons, (3) friable to very friable consistence, and (4) abrupt or clear smooth boundaries between humus and nonhumus horizons. The clay mineralogy of the ... consists largely or wholly of Al complexed with humus (pyrophosphate-extractable Al). The nonallophanic Andosols had mostly ... the organic carbon content. A remarkable accumulation of humus took place in the nonallophanic Andosols and was closely correlated with the formation of Al-humus complex. The high CEC of these soils was ...

Tópico(s): Soil Carbon and Nitrogen Dynamics

1985 - Lippincott Williams & Wilkins | Soil Science

Jornais Acesso aberto

... Imperialism, Substantial Assistance, Natal Pioneer Dead, Peas as Humus, Heroes of the "Briton", Financial Crisis Anxiety in ...

1907 - Gale Group | NCCO EuropeAfrica

Artigo Revisado por pares

Gunnar Ogner,

Abstract Crust, felty, greasy and granular raw humus were analysed by wet chemical methods and by 13C NMR. The amounts of amino acids, monosaccharides and aliphatic dicarboxylic acids were determined and ... the total sample carbon. Degradation of greasy raw humus yields half the amount of monosaccharides and twice ... aliphatic dicarboxylic acids found in the other raw humus types. This result is confirmed by 13C NMR. ... indicate great similarity between crust and felty raw humus, whereas greasy raw humus differs clearly from those ...

Tópico(s): NMR spectroscopy and applications

1985 - Elsevier BV | Geoderma

Artigo Revisado por pares

J.A. Adams,

Samples of strongly acid forest litter and humus from beneath Sitka spruce, heather, Scots pine and larch from two sites in north-east Scotland were incubated aerobically at 20°C in ... the Glen Tanar site, spruce litter and larch humus showed significant nitrification and ammonification whereas spruce humus and Scots pine humus produced only NH4+-N. Heather humus showed no net mineralization. At the Fetteresso site, ... production of NO3−-N in both litter and humus. Amendment of the samples with organic N as ...

Tópico(s): Peatlands and Wetlands Ecology

1986 - Elsevier BV | Soil Biology and Biochemistry

Artigo Revisado por pares

J. Sevink, A.C. Imeson, J.M. Verstraten,

... soils have well developed mor or moder type humus forms. Mor type humus forms were observed in soils with a shallow ... water repellent Ae or E horizon. Moder type humus forms, with a gradual transition between the ectorganic ... that these conditions have a strong control over humus form development. Quantities of organic matter (ectorganic layer + ... mor to about 10 kg/m2 in moder humus forms, the difference being due to the presence ... simulator experiments showed that slopes with mor type humus forms are likely to produce hillslope runoff during ...

Tópico(s): Hydrology and Sediment Transport Processes

1989 - Elsevier BV | CATENA

Artigo Revisado por pares

Anders Hargeby, R. C. Petersen,

... 0) with three concentrations of XAD‐extracted aquatic humus was treated in the laboratory. 2. Exposure to pH6.0 water without humus added resulted in 92% mortality after 3 weeks. Humus, added at concentrations of 7 and 20 g ... than animals kept at pH 7.3. 4. Humus had no significant effects on growth, food conversion ... for body water content to decrease with increased humus concentration. The effects of humus on growth and food conversion of G. pulex ... this study do not support the contention that humus acts as a free coupler to lower metabolic ...

Tópico(s): Mollusks and Parasites Studies

1988 - Wiley | Freshwater Biology

Artigo Revisado por pares

Sayanti Datta, P. N. Takkar, U. K. Verma,

... of this investigation is to study how adsorbed humus on clay minerals affects kinetics of dissolution of ... in terms of K and Si release. Clay–humus complexes were isolated from soil samples collected from ... rice–wheat and maize–wheat cropping systems. Clay–humus complexes were subjected to repeat extraction with 100 ... tartaric acid solutions before and after removal of humus with 30% hydrogen peroxide and the resultant release ... potassium and silica was measured. Before removal of humus, K release followed Elovich kinetics for the maize– ...

Tópico(s): Soil and Unsaturated Flow

2009 - CSIRO Publishing | Soil Research