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The present study aims to focus on the possibility of developing new eco-friendly azo dyes with good colouristic application properties, exhibiting biological and pharmacological activities.

Coupling of 4-hydroxycoumarin with a variety of aromatic diazonium salts of 2-aminothiazole, 2-aminobenzothiazole, 4-aminoantipyrine, 4-aminoacetophenone, adenine sulphate, a-naphthylamine and sulphadimidine to produce novel azo dyes. The compounds were fully characterised using spectroscopic and analytical methods. All of the compounds were tested for their antimicrobial, anticancer and antioxidant activities. The prepared dyestuffs were dyed on polyester fabrics and subsequently their dyeing properties, light, washing, perspiration, rubbing and sublimation fastness were determined.

The spectroscopic data of the synthesised compounds have provided decisive evidence that such compounds exist in the solid state as the azo-dike to form C and in solution in equilibrium tautomer forms A, B and D. The prepared dyestuffs are suitable for either heat transfer printing or traditional printing on polyester and nylon 6 fabrics. The prints obtained from the dyes possess high colour strength, as well as good overall fastness properties. Also the synthesised compounds exhibit good biological and pharmacology activity.

Synthesis of these seven azo dyes for textile dyeing had never been reported previously.

The dyestuffs derived from 4-hydroxycoumarin are reasonable azo disperse dyestuffs giving good all round fastness properties on polyester fabrics.

Production of less expensive and new eco-friendly dyes exhibit antimicrobial and anticancer activity.

It provided a potentially simple way to synthesize novel coumarin azo-dyes exhibit good biological and pharmacology activity and also exhibit good overall fastness properties.

The purpose of this paper is to illustrate the benefits of reintroducing traditional grazing systems practices for improving arid rangelands. Grazing is the most extensive land use in southern Tunisia, but the rangelands have suffered many decades of severe degradation due to profound socioeconomic changes and the emergence of an agro-pastoral society in place of the former pastoral one. Traditional grazing systems (gdel and herd mobility), which had historically allowed for grazing deferment and control of grazing livestock were abandoned. Yet grazing management strategies are important tools to sustain integrated livestock rangeland production systems in dry areas in the face of ongoing climate change and human pressure.

This study assesses the revival of traditional best practices of rangeland resting in a representative community. Total plant cover, species composition, flora richness and range production were determined in six rangeland sites subjected respectively to one, two and three years of rest; one and two years of light grazing after rest; and free grazing (control).

Results showed that dry rangelands keep their resilience to the negative effects of climate change once human pressure is controlled. A maximum of two years of rest is enough to sustainably manage the rangelands in southern Tunisia, as this protection showed considerable and positive effects on the parameters scored.

The revival of the traditional best practices under new arrangements adapted to current biophysical and socioeconomic conditions would be an excellent tool to mitigate the negative effects of frequent droughts and reduce the animal feed costs that poor farmers face.