Socioeconomic determinants of organic cotton adoption in Benin, West Africa

Organic cotton relies on ecological processes and the use of natural resources to sustain the production system, unlike conventional cotton, mainly characterized by massive utilization of synthesis chemicals. In West Africa, where rural livelihoods are particularly vulnerable, organic cotton is expected to contribute not only to poverty reduction but also to strengthen households’ resilience. The objective of this study was to assess institutional and socioeconomic factors determining farmers’ decisions to adopt organic cotton. For this purpose, we applied a probit model on empirical data collected from producers of the Centre and the Northern parts of Benin. Overall, we found that organic cotton adoption is mainly determined by farmers’ socioeconomic characteristics, the physical distance between farm and house, and contact with extension and advisory services. Organic farming is more attractive to women compared to conventional farming. This because such type of cotton farming enables women to hold a separate cotton farm and thus increase their economic independence, whereas with the conventional system they depend mainly on the farm of the (male) head of the household. Older, less educated and low-income farmers who express environmental concern are more likely to adopt organic cotton. Subsequently, organic cotton should be considered as a prospective policy option to reach the poor and strengthen their livelihoods conditions while contributing to preserve the environment and natural resources. Furthermore, farmers who have their farm near home are more likely to adopt organic farming than those who have the farm far from their home. It also came out that organic farmers have more contacts with advisory and extension services. Finally, the study noted that there is still a need to enhance the extension system by: (1) exploring, designing, and upgrading innovative pedagogic tools such as videos and mobile phone technology to foster learning; and (2) strengthening organic farmer’s organizations and the linkage with agricultural research organizations for technology development

Assessment of heavy metals in sediment and in suspended particles affected by multiple anthropogenic contributions in harbours

La Goulette, Rades and Sidi Bou Said harbours are considered as the most important commercial and tourist ports in the Gulf of Tunis. They are located on the northeast coast of Tunis and receive industrial and municipal wastewaters from Tunis city. The contamination level of copper, lead, zinc, cadmium, manganese, iron, total nitrogen and total organic carbon in the surface sediments was assessed on the basis of the enrichment index factors and corresponding to sediment quality guidelines. The results revealed moderate to highly elevated concentrations near to the sites of intense industrial, shipping and/or commercial activities suggesting a direct influence of these sources. In winter and summer, concentrations varied for cadmium, 0.28–1.40 mg kg-1; lead, 18–217 mg kg-1; zinc, 87–459 mg kg-1; copper, 8–121 mg kg-1; manganese, 208–254 mg kg-1; and for iron, 24–40 g kg-1. Furthermore, in summer the concentration of the total organic carbon and the total nitrogen contents range between 4.3–6.5 % and 0.06–0.49 % with an average value of 5.9 and 0.15 %, respectively. Whereas, in winter, total organic carbon and the total nitrogen concentrations varied between 2.3–9.6 % and 0.03–0.22 % with an average value of 6.1 and 0.14 %, respectively. The levels of lead, copper, zinc and iron in suspended particulate matter content range between 3.1–27.5 mg kg-1; 0.4–11.7 mg kg-1; 1–1.5 mg kg-1; 1.2–1.7 g kg-1, respectively. This study revealed that heavy metals pollution is mainly localized in the commercial (Rades) and fishing (La Goulette) harbours and not in the yachting (Sidi Bou Said) harbour

Determination of Synthetic Musks in Surface Sediment from the Bizerte Lagoon by QuEChERS Extraction Followed by GC-MS

International audienceA new analytical method for the simultaneous determination of eight synthetic musks compounds (SMs) including five polycyclic musks (PCMs) and three nitro musks (NMs) was validated for sediment samples based on a simple QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) sample preparation procedure followed by gas chromatography–mass spectrometry (GC–MS). Good analytical performances were obtained for all the target compounds. For the validation of the method, internal calibration (IC) and internal calibration with QuEChERS (ICQ) were compared. Good linearity was obtained for both calibration methods with determination coefficients (R2) ranging between 0.990 for Musk Xylene (MX) and 0.999 for Tonalide (AHTN) with IC and between 0.991 for Musk Ketone (MK) and 0.999 for Traseolide (ATII) with ICQ. The repeatability ranges were 0.1 %–1.9 % with the IC and 0.1 %–2.6 % with the ICQ. The apparent recoveries obtained for SMs in the standard reference sediment (SRM1944) varied in the range of 70 %–98 % and 75 %–103 % in the sediment from the Bizerte Lagoon (Tunisia). The absolute recoveries ranged between 61 % and 92 % for the SRM1944 and between 61 % and 89 % in the sediment from the Bizerte Lagoon. The limits of detection (LOD) calculated for the two main compounds, Galaxolide (HHCB) and Tonalide (AHTN) were 0.3 and 0.1 ng g−1 respectively. The LODs obtained for ADBI (Celestolide), AHMI (Phantolide), ATII (Traseolide), MM (Muks mosken), MK (Musk Ketone) and MX (Musk Xylene) were 0.08, 0.12, 0.03, 0.34, 0.11, 0.08, 0.10 and 0.15 ng g−1 respectively. The levels of ∑SMs in surface sediments from the Bizerte Lagoon ranged from 1.4 to 4.5 ng g−1, which are 1000 times lower that the predicted no effect concentration (PNEC) for marine organisms

Distributions of organochlorine pesticides and polychlorinated biphenyl in surface water from Bizerte Lagoon, Tunisia

The contamination of the marine environment by organic pollutants is a matter of great concern. Bizerte Lagoon is the second largest lagoon in Tunisia, and is known for different industry and fishing activities. The objective of this work is to investigate the distribution of seven polychlorinated biphenyls (PCBs) and nine organochlorine (OCPs) pesticides in water samples collected from the Lagoon of Bizerte. Extraction of water samples was performed by liquid-liquid extraction with hexane. Gas chromatography with Ni-63 electron capture detector was used to perform qualitative and quantitative determinations. The average concentrations of OCPs were 0.42 and 14.92ngL(-1). For PCBs the concentrations range between 3 and 10.4ngL(-1). The predominant PCB congeners in the surface water were PCB 28 (0.2-1.4ngL(-1)) and PCB 52 (0.8-3.5ngL(-1)). The most widespread OCPs were DDTs with a concentration varied between ND and 8.51ngL(-1), heptachlor (ND and 7.83ngL(-1)), and endrin (ND and 1.51ngL(-1)). These concentrations are generally similar to the background levels from the Mediterranean Sea

Inorganic mercury and methylmercury in surface sediments and mussel tissues from a microtidal lagoon (Bizerte, Tunisia)

cited By 18International audienceThe aim of this study was to investigate the distribution of mercury compounds in marine sediments and mussel tissues collected in the lagoon of Bizerte, Tunisia, during two seasons (summer and winter). Inorganic mercury (Hg2+) concentrations in sediments were found to be highly variable, ranging from 0.04 nmol.g-1 to 3.22 nmol.g-1 (dry weight) with a mean value of 0.52 nmol.g-1. Anthropogenic sources of Hg2+, most probably metallurgy or tire production industries, have been evidenced. The mean concentration of monomethylmercury (MeHg+) in the surface sediments is 2.32 pmol g-1 ranging from below the detection limit (0.45 pmol.g-1) to 14.6 pmol.g-1. No significant variation was observed between winter and summer seasons for both mercury species concentration in the sediments. The Hg2+ concentrations in mussel tissues are also variable, ranging from 0.007 to 1.347 nmol.g-1 (dry weight). The mean concentration is 0.70 nmol.g-1. In these tissues, Hg2+ is generally the major compound, making up ca. 88% of total mercury concentrations. However, methylmercury concentrations are significant and homogeneous, ranging from 62 to 121 pmol.g-1 (mean 96 pmol.g-1 . The results suggest that a fraction of the inorganic mercury load in the sediments of the lagoon undergoes methylation pathways. MeHg+ produced is assimilated in the mussels more readily than Hg2+

Contaminated sediment resuspension induces shifts in phytoplankton structure and function in a eutrophic Mediterranean lagoon

International audienc