Gbandi Djaneye-Boundjou

Contribution à la connaissance de l'écologie d'Eichhornia crassipes (Mart.) Solms-Laub. (Pontederiaceae) et de Pistia stratiotes L. (Araceae) dans la région maritime orientale du Togo

Abstract The water plans of the Togolese East maritime region are all invaded by floating weeds. Phytosociological study of these ones show two communities: Lemno paucicoctatae-Pistietum stratioitis, a Myriophyllum spicatum community. Eichhornia crassipes is quite rare despite its presence on the Lomé lagoon and on the Mono river. Water chemical analysis show that values of conductivity, hydrotimetric title (TH), chloride ions and phosphate ions measured at a youthful stage of Pistia were lower than those measured with its death. The reverse phenomenon is observed for nitrate and ammonium ions. Feeble values of conductivity, TH and chlorides favourish nitrates and ammonium assimilation by floating species. Statistical analysis of the hydro-chemical parameters permit to classify these water biotopes in ponds, swamps, streams and lagoons.

QUALITÉ ET POLLUTION DES EAUX D’UN HYDROSYSTÈME LITTORAL TROPICAL : CAS DU SYSTÈME LAGUNAIRE DE LOMÉ, TOGO

The field of Depth of Anaesthesia (DOA) is a very challenging area for neuro-fuzzy control since direct measurements are unavailable. During anaesthesia, the blood pressures (BP), the mean arterial blood pressure (MAP) and the heart rate (HR) are monitored to maintain hemodynamic stability and to assess the level of consciousness. The purpose of this study is to find the best input-output definitions in the Adaptive-Network-based Fuzzy Inference System (ANFIS) to control the Sevoflurane dose to patient under the general anaesthesia with the classical MAP and HR parameters. The best models have been found among many possible input combinations. This study helps to provide an alternate control for the dose of Sevoflurane which is widely used as an anaesthetic agent. The models have been trained and validated by clinical data. The results show that the patients can be modelled by ANFIS if sufficient HR and MAP data are provided. Furthermore, the model performance could be increased if the patients are grouped as adults and children. The performance (up to 0.99) in this study is comparable to recent works in similar subject which detect DOA by Electroencephalograms (EEG).

Assessment of pesticide residues and trace element contamination in market gardens of Togo

All intensive agriculture, like periurban agriculture, uses massive inputs such as agrochemicals. This study aims to assess the environmental impacts of agrochemical use in periurban agriculture in Togo. It was based on the chemical analyses of soil, water and vegetable samples. These analyses were carried out by gas chromatography on extracts from soil, water and vegetable samples. In soil samples, the concentrations of pesticide residues are lower than 20 ig/kg of dry material. For water samples, contamination levels vary from 0.02 to 1.1 ig/L of dry material with the highest levels for metalaxyl M (1.1 ig/L) and for dimethoate (1 ig/L). In vegetables, the concentrations measured are between 0.01 and 0.1 mg/kg of dry material. All these concentrations are affected by a positive factor of the maximum limits of residues. These agrochemicals, coupled with periurban environmental management led to the high concentrations of trace elements. Lead and cadmium concentrations in water are 10 and 21 times respectively higher than the maximum concentration allowable for drinking water by the WHO. The study showed that inappropriate use of agrochemicals in Togolese periurban agriculture creates ecological disturbances that could affect produce quality. Key words : Togo, periurban agriculture, agrochemicals, pesticide residues, trace element.