Volatile fatty acids (VFAs) represent the major organic constituent of landfill leachate and provide the greatest potential for leachate induced organic contamination of groundwater (e.g. as represented by an increase in the concentration of dissolved organic carbon and chemical oxygen demand). Long-term diffusion tests were performed for laboratory-compacted clayey soil plugs exposed to contin...

One motivation for our study concerns an environmental application that regards the identification of pollution sources in surface water: in a river, for example, the introduction of organic matter which could have as origin city sewages, industrial wastes,... usually drops to too low the level of the dissolved oxygen in the water. Since the lack of dissolved oxygen represents a serious threat ...

The toxicity of chromium (Cr) to biota is related to its chemical forms and consequently to the redox conditions of soils. Hexavalent Cr[Cr(VI)] may undergo natural attenuation through reduction processes. In this study, the reduction kinetics of Cr(VI) in seven soils and its relationships with soil properties were investigated with laboratory incubation experiments. The results indicate that t...

Considering the importance of lignocellulose macrophyte-derived for the energy flux in aquatic ecosystems and the nutrient concentrations as a function of force which influences the decomposition process, this study aims to relate the enzymatic activity and lignocellulose hydrolysis in different trophic statuses. Water samples and two macrophyte species were collected from the littoral zone of ...

One motivation for our study concerns an environmental application that regards the identification of pollution sources in surface water: in a river, for example, the introduction of organic matter which could have as origin city sewages, industrial wastes,... usually drops to too low the level of the dissolved oxygen in the water. Since the lack of dissolved oxygen represents a serious threat ...

The pelagic ocean harbors one of the largest ecosystems on Earth. It is responsible for approximately half of global primary production, sustains worldwide fisheries, and plays an important role in the global carbon cycle. Ocean warming caused by anthropogenic climate change is already starting to impact the marine biota, with possible consequences for ocean productivity and ecosystem services....

Increasing wildfire activity in the Alaskan Arctic may result in new sources of black carbon (BC) to arctic watersheds. Black carbon, primarily comprised of condensed aromatics, is one of the most chemically recalcitrant fractions of organic carbon. However, lateral transfer of particulate and dissolved BC from soils to sunlit surface waters is increasingly suggested to result in the photochemi...

............................................................................. 1 Humic acids....................................................................... 3 Introduction.................................................................... 1 Field studies....................................................................... 4 Analytical developments..........................................

New stainless steel active fogwater collectors were designed and used in Davis (CA, USA) to collect fogwater for the speciation of organic matter. Organic compounds in fog samples were extracted by liquid–liquid extraction and analyzed by gas chromatography coupled to mass spectrometry. Numerous organic compounds, including various alkanes, polycyclic aromatic hydrocarbons (PAH) and alkanoic ac...