Soil organic carbon content and mineralization controlled by the composition, origin and molecular diversity of organic matter: A study in tropical alpine grasslands

The present study attempts to relate the soil organic carbon content with four different land uses (Faculty of Agriculture Teaching and Research farm, cashew plantation and Agricultural and Bioresources experimental farm and oil palm plantation) which come under South west, Nigeria. The objective of the study was to assess the effects of different land uses on soil organic carbon. The sampled soils were collected from different land uses at 0–15 cm (surface), 15 – 30 cm and 30 - 45 cm (sub-surface) depth and were analyzed for soil physical properties with standard procedures. Data were analysed using descriptive statistics and analysis of variance (ANOVA). The results indicated that the oil palm plantation land use recorded the highest mean of soil organic carbon content compared with other land use types at 0 – 15 cm soil depth (23 ±4 g kg-1), which was 1.5, 2.6 and 53.3 % more than in the Faculty of Agriculture Teaching and Research farm land, the cashew plantation land and the Agricultural and Bioresources experimental farm land. This is attributed to more inputs of litter fall and reduced decomposition of organic matter. Similarly, the lowest soil organic carbon content under Agricultural and Bioresorces engineering as compared to others was attributed to reduce of organic matter and frequent tillage which encouraged oxidation of organic matter. The finding indicated that the means of soil organic carbon were significantly different (P < 0.05) between the land use types. Conservation farming should be practiced

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A plant ecology approach to digital soil mapping, improving the prediction of soil organic carbon content in alpine grasslands

Geoderma ◽

10.1016/j.geoderma.2012.04.002 ◽

2012 ◽

Vol 187-188 ◽

pp. 102-116 ◽

Cited By ~ 14

Author(s):

Cristiano Ballabio ◽

Francesco Fava ◽

Alexandra Rosenmund

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Carbon Content ◽

Plant Ecology ◽

Soil Mapping ◽

Digital Soil Mapping ◽

Organic Carbon Content ◽

Alpine Grasslands ◽

Soil Organic Carbon Content

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Adsorption of atrazine, simazine, and glyphosate in soils of the Gnangara Mound, Western Australia

Soil Research ◽

10.1071/sr9960599 ◽

1996 ◽

Vol 34 (4) ◽

pp. 599 ◽

Cited By ~ 69

Author(s):

RG Gerritse ◽

J Beltran ◽

F Hernandez

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Soil Organic Carbon ◽

Carbon Content ◽

Adsorption Isotherms ◽

Western Australia ◽

Batch Adsorption ◽

Organic Carbon Content ◽

Soil Organic Carbon Content ◽

Adsorption Sites

Sandy soils were sampled from second rotation sites of Pinus pinaster Ait. on the Gnangara Mound in Western Australia. Adsorption isotherms were measured for atrazine [6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine], simazine [6-chloro-N,N'-diethyl-1,3,5-triazine-2,4-diamine], and glyphosate [N-phosphonomethyl-aminoaceticacid]. Adsorption isotherms were also measured for degradation products of atrazine: hydroxyatrazine [6-hydroxy-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine] (HA), desethylatrazine [6-chloro-N-isopropyl-1,3,5-triazine-2,4-diamine] (DEA); and of glyphosate: aminomethylphosphonic acid (AMPA). The adsorption of the 2 triazines was proportional to soil organic carbon content and was not affected significantly by other soil parameters. The affinity for soil organic carbon was in the order atrazine = simazine = DEA > HA. Affinity of atrazine for the type of organic matter in the Gnangara Mound soils (expressed as Koc) was significantly greater than is commonly reported for other soils. The adsorption of glyphosate and AMPA increased strongly with iron and aluminium content of soils and decreased with increasing soil organic carbon content. This would indicate that glyphosate and AMPA are mainly adsorbed by clay minerals, while soil organic matter competes for adsorption sites and inhibits adsorption. Contrary to what is usually reported for batch adsorption of pesticides in soils, significant increases in adsorption of the triazines and glyphosate were measured after 1 day of equilibration.

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