Distribution of phosphorus forms in surface soils of typical peatlands in northern Great Khingan Mountains and its potential to reconstruct paleo-vegetations

Boreal ecosystems contain a substantial fraction of the earth's soil carbon stores and are prone to frequent and severe wildfires. In this study, we examine changes in element and organic matter stocks due to a 1999 wildfire in Alaska. One year after the wildfire, burned soils contained between 1071 and 1420 g/m2 less carbon than unburned soils. Burned soils had lower nitrogen than unburned soils, higher calcium, and nearly unchanged potassium, magnesium, and phosphorus stocks. Burned surface soils tended to have higher concentrations of noncombustible elements such as calcium, potassium, magnesium, and phosphorus compared with unburned soils. Combustion losses of carbon were mostly limited to surface dead moss and fibric horizons, with no change in the underlying mineral horizons. Burning caused significant changes in soil organic matter structure, with a 12% higher ratio of carbon to combustible organic matter in surface burned horizons compared with unburned horizons. Pyrolysis gas chromatography mass spectroscopy also shows preferential volatilization of polysaccharide-derived organic matter and enrichment of lignin- and lipid-derived compounds in surface soils. The chemistry of deeper soil layers in burned and unburned sites was similar, suggesting that immediate fire impacts were restricted to the surface soil horizon.

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Effects of pH and ionic strength on the cation exchange capacity of soils with variable charge

Soil Research ◽

10.1071/sr9810093 ◽

1981 ◽

Vol 19 (1) ◽

pp. 93 ◽

Cited By ~ 30

Author(s):

GP Gillman

Keyword(s):

Ionic Strength ◽

Cation Exchange ◽

Cation Exchange Capacity ◽

Exchange Capacity ◽

Surface Soils ◽

Ph Values ◽

Variable Charge ◽

Effects Of Ph ◽

Variable Charge Soils

The cation exchange capacity of six surface soils from north Queensland and Hawaii has been measured over a range of pH values (4-6) and ionic strength values (0.003-0.05). The results show that for variable charge soils, modest changes in electrolyte ionic strength are as important in their effect on caton exchange capacity as are changes in pH values.

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Flint Implements from the Ploughlands of South-West Leicestershire

Proceedings of the Prehistoric Society of East Anglia ◽

10.1017/s0958841800023954 ◽

1918 ◽

Vol 2 (4) ◽

pp. 549-563 ◽

Cited By ~ 2

Author(s):

A. J. Pickering

Keyword(s):

Systematic Search ◽

Geological Survey ◽

Human Origin ◽

Surface Soils ◽

South West

In the autumn of 1913, Mr. T. C. Cantrill, F.G.S., of the Geological Survey, drew the writer's attention to the possibility of finding flint artefacts in the surface soils of Hinckley and neigh-bourhood wherever the chalky boulder clays and gravels were in evidence. During his survey of the drift in this district in that and the following year, he himself found a lozenge-shaped scraper (No. 163, Plate LXVIII) in a field at Sapcote, and also five spalls of unmistakable human origin in other neighbouring localities.In the winter of that year, Mr. F. C. Grimes and I began a systematic search which by the following spring had resulted in sufficient material to encourage us to further efforts, and the following notes are the result of a by no means exhaustive survey during that and the two following winters.

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