Compost derived from olive mill cake: Effects on isohumic soil quality based on humic acids characterization.

The compost effects on soil organic matter (SOM) stability were evaluated. Manure at 10 % ratio and compost at 10 %, 20 % and 40 % ratios (v/v) were added to the soil and their effects were compared to unamended control soil after 90-days of greenhouse-experiment. Humic acids (HA) and fulvic acids (FA) were extracted from two different soil-sample layers at 0-15 and 15-30 cm depth.

Biocontrol and plant growth-promoting potentiality of bacteria isolated from compost extract.

The use of compost extracts is steadily increasing, offering an attractive way for plant growth enhancement and disease management replacing chemical pesticides. In this study, potential mechanisms involved in plant growth promotion and suppressive activity against fungal diseases, of a compost extract produced from poultry manure/olive husk compost, were investigated. Results of physico-chemical and microbiological investigations showed high ability to reduce Fusarium oxysporum, Alternaria alternata, Aspergillus niger and Botrytis cinerea growth.

Geochemical behaviour of PM10 aerosol constituents under the influence of succeeding anticyclonic/cyclonic situations: case of Sfax City, southern Tunisia.

The present study investigates the geochemical behaviour of PM10 aerosol constituents (Cl, Na, Si, Al, Ca, Fe, Mg, Mn, Pb, Zn, S) at Sfax City (Tunisia) under succeeding meteorological conditions, including short-lived anticyclonic, cyclonic and prolonged anticyclonic situations. The results revealed daily total concentrations fluctuating between 4.07 and 88.

Polyphenolic compounds progress during olive mill wastewater sludge and poultry manure co-composting, and humic substances building (Southeastern Tunisia).

In Mediterranean areas, olive mill wastes pose a major environmental problem owing to their important production and their high polyphenolic compounds and organic acids concentrations. In this work, the evolution of polyphenolic compounds was studied during co-composting of olive mill wastewater sludge and poultry manure, based on qualitative (G-50 sephadex) and quantitative (Folin-Ciocalteu), as well as high pressure liquid chromatography analyses. Results showed a significant polyphenolic content decrease of 99% and a noticeable transformation of low to high molecular weight fraction during the compost maturation period.

Characterization of olive mill wastes composts and their humic acids: stability assessment within different particle size fractions.

Compost stability assessment within different particle size fractions was studied. Humic acids (HAs) were extracted from two kinds of co-composts prepared using evaporated olive mill wastewater (OMSW) or solid waste from olive oil extraction (OC) and poultry manure (PM). The elemental composition, Fourier-transform infrared spectroscopy (FTIR) and 13C-NMR (nuclear magnetic resonance) analysis and molecular weight distribution were investigated to assess the composted organic matter stability in different fractions.

Climatological aspects of aerosol physical characteristics in Tunisia deduced from sun photometric measurements.

Atmospheric and climatic data measured at Thala site (Tunisia) for a long-time period (1977-2001) are used to analyse the monthly, seasonal, and annual variations of the aerosol optical depth at 1 μm wavelength. We have shown that aerosol and microphysical properties and the dominating aerosol types depend on seasons. A comparison of the seasonal cycle of aerosol optical characteristics at Thala site showed that the contribution of long-range transported particles is expected to be larger in summer as a consequence of the weather stability typical of this season.

Biological activity during co-composting of sludge issued from the OMW evaporation ponds with poultry manure-Physico-chemical characterization of the processed organic matter.

Olive mill sludge (OMS), a by-product resulting from natural evaporation of olive oil processing effluent, poses a major environmental threat. A current cost-effective practice of OMS management is composting. A mixture of OMS (60%) with poultry manure (PM) was successfully composted for 210 days.

Elimination of polyphenols toxicity from olive mill wastewater sludge by its co-composting with sesame bark.

Olive mill wastes represent a significant environmental problem in Mediterranean areas where they are generated in huge quantities in a short period of time. Their high phenol, lipid and organic acid concentrations turn them into phytotoxic materials, but these wastes also contain valuable resources such as a large proportion of organic matter and a wide range of nutrients that could be recycled. Composting is one of the technologies used for the valorization of this effluent, producing a fertilizer useful for poor soils.

Maturity assessment of composted olive mill wastes using UV spectra and humification parameters.

In this study, two olive mill wastes - exhausted olive cake (EOC) and paste of olive mill wastewater naturally dehydrated (POMW) - were co-composted and mixed with 25% sesame bark (SB). The humification process was evidenced by quantifying the humic substances and the generally accepted humification indices: (i) the ratio of humic acid (HA) carbon to fulvic acid (FA) carbon (CHA/CFA), (ii) the ratio of water soluble organic carbon (CW) to total organic nitrogen (Cw/Norg), (iii) and the ratio of humic acid carbon to total organic carbon CHA/Corg and by determining the absorbance ratios: E2/E4, E2/E6 and E4/E6. The results showed that the time required to reach maturity was dependant on the chemical properties of the initial raw materials used.

Quality assessment of composts prepared with olive mill wastewater and agricultural wastes.

The co-composting of solid residue from olive oil production process, exhausted olive cake (EOC), with poultry manure (PM) watered with olive mill wastewater (OMW) was considered as an efficient method for the treatment of olive oil extraction effluent having high organic content including phenolic polluting compounds. The process was carried out by using three aerated windrows of variable compositions. OMW was used continuously during the bio-oxidative period, which lasted three months, to replace water for windrow moistening.