Paramètres physiques d’évaluation du comportement des feux de végétation au Togo

Au Togo, le brûlage de la végétation est une pratique agricole et culturelle très courante. Mais, au-delà de certaines normes, le feu échappe au contrôle et devient néfaste aux écosystèmes et au cadre de vie. Cette étude se propose de comprendre le comportement des feux pour une meilleure maîtrise des brûlages. Spécifiquement, les paramètres de biomasse combustible, vitesse de propagation et intensité ont été analysés pour chaque régime de feu. Le dispositif expérimental est constitué de 81 parcelles (30x80 m²) installées dans les savanes d’aires protégées. La vitesse de propagation est plus élevée en savane soudanienne (11±1 cm/s) qu’en zone guinéenne (9±1 cm/s). L’intensité va de 1972±192 à 2218±357 kW/m. La vitesse et l’intensité des feux précoces sont faibles et à portée de contrôle comparativement aux feux tardifs et de mi-saison. La connaissance des paramètres d’occurrence devient une étape incontournable dans la gestion des feux. Dans un contexte tropical et face aux défis de gestion durable des écosystèmes forestiers et d’amélioration du cadre de vie, la prévention des feux incontrôlés et la maitrise des feux utilitaires exigent une bonne compréhension du comportement des feux.© 2015 International Formulae Group. All rights reserved.Mots clés: Intensité des feux, régimes de feu, vitesse de propagation, biomasse combustibleEnglish AbstractIn Togo, burning vegetation is very common as farming and cultural practice. But, beyond some standards, fires escape from human control and become harmful to forest ecosystems and the whole environment. This study aims at a better understanding of the fires behaviours. Specifically, parameters such as combustible biomass, propagation speed and intensity have been analyzed for each fire regime. The experimental device includes 81 land plots (30x80 m²) located in the savannas of protected areas. It is pointed out that the propagation speed is higher in sudanian savannah (11±1 cm/s) than guinean’s (9±1 cm/s). The intensity varies between 1972±192 to 2218±357 kW/m. Both speed and intensity are lower and easier to be under control in the case of early fire compared to middle-season and late fires. Knowing  better fire parameters becomes an important goal to be reached in order to well address fire issues in the country. In tropical context, the prevention of wildfires and the control of utilitarian fires depend on a better comprehension of fire movement. Fire control remains important in targeting a sustainable management of forests ecosystems and for the sake of  populations’ well-being.© 2015 International Formulae Group. All rights reserved.Keywords: Intensity of fires, fire regimes, speed of propagation, combustible biomas

Usefulness of Plant Biodiversity in the Cities of Togo

In an increasingly urbanized environment, the need for greenery and flowers is being more and more felt for esthetic reasons and ecological benefits. In Togo, more than six hundred species of horticultural plants are identified and composed of approximately 59% of dicotyledons (49 families, 145 genera, and 315 species) and 37.37% of monocotyledons. Pteridophytes and gymnosperms account for less than 6%. The spectrum of morphological types indicates that herbs are account for 55%, while trees and shrubs represent 15%. More than 50% of the species of this flora is exotic horticulture. A species distribution is made according to their decorative parts and their place of use. Across the country, 55 plantings are recorded and unevenly distributed in cities. Apart from their ornamental purpose, ornamental plants are used for feeding, traditional and industrial cosmetics in psychotherapy, horticultural therapy, and in traditional and conventional medicine. In this study, 79 species from 39 families are reported as medicinal plants. The Apocynaceae and Fabaceae (six species), the Euphorbiaceae and Liliaceae (five species), the Arecaceae and Verbenaceae (four species) are the best represented families. Production systems in ornamental horticulture in Togo are very diverse in terms of speculation, access to land (variable surfaces, direct or indirect forms of tenure, acquisition methods, land use, etc.) and socio-economic profiles of farmers (men, women, young, old, people with little or no qualifications, rural to urban, etc.). The family horticultural production system, which represents over 90% of 55 horticultural farms of this study, is the main production system. It is characterized by areas of less than 0.1 hectare and farms in relative land insecurity (97% of land used belongs to the state). Throughout the system, there is a salaried labor representing 5–8% of turnover. Temporary and permanent employees are paid on weekends or at the end of the month. Farmers use gardening equipment and processing plant more or less modern including clippers, shears, pruners, and sprayers. Production units provide direct employment (more than 3 employees per unit) and directly to several hundred people. Horticulture in urban and peri-urban areas improves the living conditions of farmers (income) and the population (embellishment of streets, maintenance or creation of green area buffer) despite some negative externalities associated particularly with the use of prohibited pesticides and uncontrolled use of spaces along the roads. Its survival is threatened by many constraints, including the extension of urban housing and road building. In Togo, beneficial effects of ornamental horticulture may be more noticeable if the political authorities, private stakeholders, and the researchers work together to organize the sector. It could thus participate effectively in the formal economy and the emergence of true development plans at the municipal level

Politique publique de gestion des espaces verts de la ville de Lomé au Togo

Lomé, capitale du Togo, a connu des études qui ont montré que les espaces verts qui étaient inséparables de la ville à l’origine n’ont pas suivi l’extension spatiale et ont même disparu.  Ainsi, Lomé est caractérisée par un environnement de plus en plus urbanisé où le besoin de verdure et de fleurs est de plus en plus ressenti. Cela pose donc un problème de gestion de ces espaces verts en l’occurrence un problème de politique publique de gestion des espaces verts. Une prospection de la ville de Lomé a permis de répertorier, quantifier et de dresser la typologie des espaces verts. Des interviews ont permis d’établir le diagnostic du cadre institutionnel et juridique de ces espaces verts. Il ressort de cette étude que chaque habitant  de la ville de Lomé dispose de 0,75 m2 d’espace vert contre une norme de 10 m2 préconisée par l’Organisation Mondiale de la Santé. Et pourtant, des cadres institutionnel et juridique de mise en valeur et gestion des espaces verts existent et sont incarnés par des services publics (la direction des espaces verts, des monuments historiques et de l’embellissement ; l’atelier espaces verts de la municipalité et le service technique de la préfecture du Golfe) et la loi n°2008-005 du 30 mai 2008 portant loi-cadre sur l’environnement. Cette étude fait un bilan de la politique publique et de l’état des lieux de la gestion des espaces verts et analyse les dysfonctionnements et manquements liés aux cadres institutionnel et juridique.© 2015 International Formulae Group. All rights reserved.Mots clés: Espaces verts, politique publique, gestion municipale, LoméEnglish AbstractSome studies done in Lomé, the capital city of Togo, have shown that the green spaces which at the beginning were inseparable from the city did not follow the space extension and have even disappeared today. Therefore, Lomé is characterized today by an environment that is more and more urbanized and where the need for greenery and the flowers is more felt. This leads to a problem that is the management of these green spaces known as the problem of public of green spaces management policy. A prospecting of the city of Lomé made it possible to index, quantify and to draw up the typology of green spaces. Interviews let to establish the diagnosis of the institutional and legal framework of the green spaces. From this study it  comes out that each inhabitant of Lomé only has 0,75 m2 of green spaces against a norm of 10 m2 that is recommended by the World Health Organization. Yet, the executive and law  institutions that regularize the management of green spaces exist and are incarnated by public services (management of green spaces, historic monuments and embellishment) and the law n°2008-005 of 30 may 2008 concerning the framework law on the environment. This study is an assessment of the public policy and the inventory management of green spaces. It also analyzes the dysfunctioning and failures related to the institutional and legal framework.© 2015 International Formulae Group. All rights reserved.Keywords: Green spaces, public policies, municipal management, Lom

IN VITRO MICROPROPAGATION OF NAUCLEA DIDERRICHII (DE WILD &T. DURAND) MERRILL: EFFECT OF NODES POSITION ON PLANTLETS GROWTH AND ROOTING

In tissue culture, the reactivity of explants in culture depends on their position on mother –plant or their physiological development level. This study aims to determine the regenerative potentialities of nodes according to their position for suitable in vitro micropropagation of N. diderrichii’s seedlings. Thus the effect of uninodal explants position of Nauclea diderrichii on seedling growth and rooting was studied in vitro. Three types of nodes (apical, middle and basal node) excised from two months old seedlings were tested using Woody Plant Medium (WPM) containing 30 g/L of sucrose and solidified with agar-agar at 8 g/L. The mean number of roots and shoots per plant was scored as well as the shoots and roots length was measured after six weeks of culture. Apical nodes produced seedlings with highest number of roots (6.80 ± 2.44 roots / plant) followed by basal (5.70 ± 2.68 roots / plant) and middle nodes (4.50 ± 2.12 roots / plant). But middle and basal nodes produced the best number of shoots (1.90 ±0.31 shoots / plantlet) than that obtained with apical nodes (1.30 ±0.57 shoots / plantlet). Seedlings obtained from apical nodes expressed efficient growth (4.70 ± 1.70 cm) compared to the middle (2.18 ± 0.97 cm) and basal nodes (2.33 ± 1.08 cm). So, for a rapid in vitro production of N. diderrichii’s seedlings, apical nodes of in vitro plants are more suitable

IN VITRO MICROPROPAGATION OF NAUCLEA DIDERRICHII (DE WILD &T. DURAND) MERRILL: EFFECT OF NODES POSITION ON PLANTLETS GROWTH AND ROOTING

In tissue culture, the reactivity of explants in culture depends on their position on mother –plant or their physiological development level. This study aims to determine the regenerative potentialities of nodes according to their position for suitable in vitro micropropagation of N. diderrichii’s seedlings. Thus the effect of uninodal explants position of Nauclea diderrichii on seedling growth and rooting was studied in vitro. Three types of nodes (apical, middle and basal node) excised from two months old seedlings were tested using Woody Plant Medium (WPM) containing 30 g/L of sucrose and solidified with agar-agar at 8 g/L. The mean number of roots and shoots per plant was scored as well as the shoots and roots length was measured after six weeks of culture. Apical nodes produced seedlings with highest number of roots (6.80 ± 2.44 roots / plant) followed by basal (5.70 ± 2.68 roots / plant) and middle nodes (4.50 ± 2.12 roots / plant). But middle and basal nodes produced the best number of shoots (1.90 ±0.31 shoots / plantlet) than that obtained with apical nodes (1.30 ±0.57 shoots / plantlet). Seedlings obtained from apical nodes expressed efficient growth (4.70 ± 1.70 cm) compared to the middle (2.18 ± 0.97 cm) and basal nodes (2.33 ± 1.08 cm). So, for a rapid in vitro production of N. diderrichii’s seedlings, apical nodes of in vitro plants are more suitable

Characterization of Rainwater Drainage Infrastructure in the City of Lomé (Togo, West Africa)

Despite Togo government’s efforts to maintain and expand its storm drainage networks, urban flood disasters remain recurrent. Beyond Shallow zones occupation for construction and climatic causes, it is essential to circumscribe the determinants linked to infrastructure. Based on the inventory and characterization of rainwater drainage infrastructure, this study is a contribution to the reduction of flood risk in the city of Lome in Togo. Surveys were conducted on rainwater drainage works of the 172 paved roads in Lome. A sample of each network group is selected by considering the areas of recurring hazards and broadest catchment areas in the city for the evaluation of their structural and functional states according to the readapted VIZIR method. The relationship between these two states was computed using multiple correspondence analysis (MCA). This study reveals notable insufficiencies in rainwater drainage management in the city, expressed by the existence of roads built without drains, gutters without outlets, and open gutters and makeshift trenches built by the population. Functionally and structurally, almost all the structures are constructed of reinforced concrete. The most cracked are the mainly open pit (92.02%) works of the lagoon complex. The retention basin network includes 36 retention ponds 18 of which are interconnected, 11 drained by gravity and 4 by pumping. The latter are inherently hazardous insofar as pumping energy is not guaranteed. The MCA has shown that the network of piping related to the retention ponds are in similar conditions, and that generally, the closed gutters are not cracked while the open gutters are cracked

Integrating smallholders into forest landscape restoration

ITTO is promoting the participation of smallholders in six West African countries in efforts to restore 20 million hectares of degraded land by 203

Nitrogen Moderate Rates’ Effects on the Performance of Cocoa Seedlings (Theobroma Cocoa Linn.) in the Forest Zone of Togo (West Africa)

The cocoa trees nutrient requirements coverage, especially in nitrogen (N), remains essential for a better growth of the seedlings. The objective of this study was to determine the effects of the moderate nitrogen doses on the agronomic performance of the nursery cocoa seedlings in Togo’s forest zone. Trials were conducted in a complete randomized plot design with four replicates to identify the optimal complementary nitrogen dose helpful for better growth and nutrition of cocoa seedlings. The doses tested were 0; 0.5; 1 and 1.5 g.plant-1 of urea (46% N). The results showed that the doses of 0.5 and 1 g.plant-1 were the most likely to provide the best agronomic performance of nursery cocoa seedlings in the forest zone of Togo. However, the dose of 1 g.plant-1 was optimal for good growth and balanced nutrition of cocoa seedlings and would therefore be recommended for the management of cocoa nurseries in the area