INTRODUCTION Complex organic compounds found in oil and sediments linked with a particular source (such as algae, bacteria or vascular plants) are defined as biomarkers and are useful dating indicators in organic geochemistry. METHODS AND RESULTS This paper presents the composition of the organic matter (OM) on marine surface sediments from a degraded Tunisian coast analysed by pyrolysis and ...

One of the greatest challenges in understanding the Amazon basin functioning is to ascertain the role played by floodplains in the organic matter (OM) cycle, crucial for a large spectrum of ecological mechanisms. Fatty acids (FAs) were combined with environmental descriptors and analyzed through multivariate and spatial tools (asymmetric eigenvector maps, AEM and principal coordinates of neighb...

Nitrification, the chemoautotrophic process by which NH4-N is converted to NO,-N, is an integral biogeochemical transformation in stream ecosystems. Previous research has shown that experimental addition of dissolved organic C inhibits rates of nitrification, and that NH4-N addition stimulates rates of nitrification. In many streams, large amounts of C and N may be present in particulate and so...

Lack of sufficient information on conservation tillage systems leads to the dominating use of conventional tillage practice in most parts of Iran. Testing other management practices may help in decision making regarding the types of tillage systems that reduce soil deterioration. A three- years field experiment was conducted to study the effects of conventional (CT), reduced (RT) and no-till (N...

The effect of different aeration rates on the organic matter (OM) degradation during the active phase of oil palm empty fruit bunch (EFB)-rabbit manure co-composting process under constant forced-aeration system has been studied. Four different aeration rates, 0.13 L min(-1) kg(DM)(-1),0.26 L min(-1) kg(DM)(-1),0.49 L min(-1) kg(DM)(-1) and 0.74 L min(-1) kg(DM)(-1) were applied. 0.26 L min(-1)...

24-hour samples of pm1 (submicron particles, aerodynamic diameters ≤1 μm) and pm2.5(fine particles, aerodynamic diameters ≤ 2.5 μm) were collected at a quasi-rural area in racibórz (1 january-30 june 2011). the samples were analysed for carbon (organic and elemental), water-soluble ions (na+,nh4 +, k+, mg2+, ca2+, cl-, no3 -, so4 2-) and concentrations of 21 elements with a carbon analyser (sun...

Cattle diet can impact manure quality and quantity, but has minimal impact on methane production from anaerobic digestion of manure. Quality of manure, measured as organic matter (OM) content, does affect methane production and is largely impacted by the environment cattle are housed in and methods used to collect manure. In three anaerobic digestion trials, as the amount of ash contamination o...

The main aim of this study was to examine the influence of exposure and consequently climate, on the chemical weathering of soils which had developed after the ice retreat of the last glaciation in Northern Italy. This was done by comparing soils developing at northand south-facing sites on siliceous parent material. There is very little data available on weathering rates and organic matter (OM...

Sorption-desorption experiments of fluorene (FLU) and fluoranthene (FLT) in soils were carried out and correlated to their removal from aged contaminated soils using aqueous solutions in the absence and in the presence of hydroxypropyl-β-cyclodextrin (HPBCD) as the extraction agent. FLU became more resistant to extraction in aged contaminated soils due to its initial adsorption onto the mineral...

lack of adequate organic matter (om) in the agricultural soils of iran is responsible for the poor physical condition of these soils. thus, increasing soil om is very important. on the other hand, the eutrophication of surface water caused by continuous use of phosphorus (p) fertilizer has created an interest in the combined use of organic wastes and p fertilizer. hence, the present study was u...