Methode zur Analyse von raumrelevanten Prozessen in Entwicklungsländern: Das Beispiel des Küstenraums von Benin. Méthode d\u27analyse de processus spatiaux dans les pays en développement: l\u27exemple de la zone côtière du Bénin

In developing countries there is a lack of space-oriented data. This complicates the implementation of different measures in existing social, economical and ecological systems and also restricts the estimation of future risks. Since systematic and periodical surveys in the sense of a census concept are mostly unrealistic, a method is needed to produce sufficiently adequate estimations of processes by random samples and indicators. This case study aims at developing a method on the basis of the combination of the representative samples and the indicator-based approaches for analyzing space relevant socioeconomic and ecological processes in Benin. In total we identified three main processes in the coastal area of Benin: the migration into coastal zone, the environment changes (land use, climate change and natural risks) and the vulnerability of local residents. Method consisted to two types of surveys: the interrogation of responsible persons in public office (32 semi-structured interviews) and of the population groups (667 structured interviews). These groups were distinguished according to ethnicity, gender, age as well as location of the dwelling place (rural or urban zone). In total, 262 women and 405 men belonging to the ethnic groups Fon, Yoruba, Houedah, Xla, Toffinou, Wéménou and Gun were interviewed. Members of each ethnic group were grouped according to sex (men and women), marital status and age (young adults, adults and elderly persons). For the data analysis, we used the log (x+1), the analysis variance using 4 factors, the Principal Component Analysis (PCA), the Factor Analysis (AFC) and Log-linear analysis. Multivariate analysis was applied to define the spatial variability of the vulnerability in the area of investigation. Results showed that: (1) the coastal area of Benin have the highest population density in the country, which can be attributed to migration and an increase in population, (2) there is a relationship between ethnicity and incidence of occupation as well as between religious affiliation and incidence of occupation, (3) the coastal area experiences numerous environmental problems and the effects of climate change, (4) all this has an impact on the socioeconomic components of the coastal area and increase the vulnerability of the coastal inhabitants, (5) this leads to the marginalization of actor groups and social problems, (6) the local population has certain patterns to explain natural and coastal risks and of vulnerability, (7) therefore, their reasoning of possible actions in response to issues which arise differs markedly from that of public administration, (8) taking into account this rationality is crucial in the participative coastal zone management. The method used is applicable for the analysis of regional processes when dealing with insufficient data. In addition it is transferable to other tropical coastal regions with a similar set of data problems. Therewith, the conducted methodology has successfully proven to be a suitable alternative under the specified conditions. In the end the new approach to detect spatially relevant processes with heterogeneous data sets, combing remote sensing, GIS and socioeconomic surveys for further research is identified to overcome the limitations of the achieved results that still exist

Methode zur Analyse von raumrelevanten Prozessen in Entwicklungsländern: Das Beispiel des Küstenraums von Benin = Méthode d\u27analyse de processus spatiaux dans les pays en développement: l\u27exemple de la zone côtière du Bénin

In developing countries there is a lack of space-oriented data. This complicates the implementation of different measures in existing social, economical and ecological systems and also restricts the estimation of future risks. Since systematic and periodical surveys in the sense of a census concept are mostly unrealistic, a method is needed to produce sufficiently adequate estimations of processes by random samples and indicators. This case study aims at developing a method on the basis of the combination of the representative samples and the indicator-based approaches for analyzing space relevant socioeconomic and ecological processes in Benin. In total we identified three main processes in the coastal area of Benin: the migration into coastal zone, the environment changes (land use, climate change and natural risks) and the vulnerability of local residents. Method consisted to two types of surveys: the interrogation of responsible persons in public office (32 semi-structured interviews) and of the population groups (667 structured interviews). These groups were distinguished according to ethnicity, gender, age as well as location of the dwelling place (rural or urban zone). In total, 262 women and 405 men belonging to the ethnic groups Fon, Yoruba, Houedah, Xla, Toffinou, Wéménou and Gun were interviewed. Members of each ethnic group were grouped according to sex (men and women), marital status and age (young adults, adults and elderly persons). For the data analysis, we used the log (x+1), the analysis variance using 4 factors, the Principal Component Analysis (PCA), the Factor Analysis (AFC) and Log-linear analysis. Multivariate analysis was applied to define the spatial variability of the vulnerability in the area of investigation. Results showed that: (1) the coastal area of Benin have the highest population density in the country, which can be attributed to migration and an increase in population, (2) there is a relationship between ethnicity and incidence of occupation as well as between religious affiliation and incidence of occupation, (3) the coastal area experiences numerous environmental problems and the effects of climate change, (4) all this has an impact on the socioeconomic components of the coastal area and increase the vulnerability of the coastal inhabitants, (5) this leads to the marginalization of actor groups and social problems, (6) the local population has certain patterns to explain natural and coastal risks and of vulnerability, (7) therefore, their reasoning of possible actions in response to issues which arise differs markedly from that of public administration, (8) taking into account this rationality is crucial in the participative coastal zone management. The method used is applicable for the analysis of regional processes when dealing with insufficient data. In addition it is transferable to other tropical coastal regions with a similar set of data problems. Therewith, the conducted methodology has successfully proven to be a suitable alternative under the specified conditions. In the end the new approach to detect spatially relevant processes with heterogeneous data sets, combing remote sensing, GIS and socioeconomic surveys for further research is identified to overcome the limitations of the achieved results that still exist

Effets De La Variabilite Climatique Sur Le Rendement De Quelques Cultures Vivrieres Dans Le Nord-Est Du Benin

Plusieurs études effectuées ces dernières années au Bénin révèlent que l’agriculture est de plus en plus affectée par les effets néfastes de la variabilité climatique. La présente étude vise à déterminer les effets de la variabilité climatique sur les rendements agricoles des spéculations telles que le maïs, le niébé, le sorgho, et l’arachide dans le Nord-est du Bénin et d’évaluer la conformité entre les données climatiques et la perception des producteurs de la variabilité climatique. La méthodologie adoptée est l’analyse de régression linéaire entre les anomalies de températures, de pluviométrie et de rendements préalablement calculés pour les quatre cultures et par Commune d’étude sous le logiciel R 3.3.1, suivie des entretiens structurés sur la perception des producteurs face à la variabilité climatique et le rendement agricole, effectués auprès de 240 producteurs répartis dans quatre Communes du milieu d’étude. Une AFC et un test Chi2 ont été effectués sur les données de perception. Ainsi, de l’analyse des modèles linéaires simples réalisés entre les anomalies de rendements et les anomalies de paramètres agro climatiques, il ressort une significativité globale des variables de la température et de la pluviométrie sur le rendement du maïs, du sorgho, du niébé et de l’arachide. Les paramètres de températures (T max, Tmoy, Tmin) et de précipitations qui influent sur les rendements de cultures varient en fonction du milieu et de la spéculation agricole. De plus, en se référant à la perception des producteurs de l’effet de la variabilité climatique sur la production agricole, l’inondation et la mauvaise répartition des pluies sont les manifestations observées à Kandi et Nikki tandis qu’à Bembèrèkè et Tchaourou, c’est plutôt la rareté des pluies et les vents violents. Ces manifestations ont pour causes, selon les enquêtés, la déforestation (90 %), les phénomènes naturels (57,92 %), le non-respect des interdits (42,92 %), avec pour conséquences sur les cultures, la baisse des rendements de maïs, sorgho, niébé et arachide. Different studies show that these last years in Benin the agriculture is affected harshly by the climatic variability. The present work aims at determining the effects of climate variability on agricultural yields of foodcrops, such as maize, cowpea, sorghum, and groundnut in the North-east of Benin and to assessing the compliance between the climate data and the perception of farmers regarding climate variability. For this purpose two types of data were used. There were agricultural statistics of crop yields and meteorological data. In addition structured interviews were conducted with 240 farmers in the four districts of the study area. Questions of the interviews were related to the perception of the farmer of climate variability and effects on agricultural production. Data processing consisted of the calculation of anomalies as well a annual crops yields indexes for each of the four (04) targeted crops. A regression analysis had been carried out using crops yields and meteorological parameters for the period 1981 to 2012. The analysis was performed in the R software 3.3.1 for regression analysis moreover AFC and Chi2 test for perception data. Results, showed that the linear models using the anomalies of crop yields and the anomalies of climate parameter revealed a high link between both parameters. It stands out an over significance of the variables of temperature and rainfall on the yield of maize, cowpea, sorghum, and groundnut. In fact, the meteorological data (T max, Tmoy, Tmin, Pmoy) influence yields of foodcrops varied regardind districts and crops. Farmers perceive climate variability and their perceptions were the flooding, rain irregularity observed in Kandi and Nikki while in Bembèrèkè and Tchaourou are the rarity of the rains and the strong winds. These events are caused, according to the respondents, deforestation (90%), natural phenomena (57.92%), non-compliance with prohibitions (42.92%), with consequences for crops, the decline in maize, cowpea, sorghum, and groundnut yields

Understanding Coastal Citizens Perception on Urban Green Spaces: Evidence from Benin Republic in West Africa

Urban Green Spaces (UGS) have several benefits for humans and environment. Despite these numerous benefits and important roles, UGS are often disregarded because their ecosystem services are not quantified and well-understood in developing countries. Until now, no study was carried out regarding the local perception, urban green spaces use values, threats and management strategies in Benin. This study was undertaken to assess the importance of UGS to citizens’ communities, to identify threats to viability and communities’ commitment or willing to adhere participatory suitable management in three cities (Ouidah, Cotonou and Porto-Novo) located in the coastal area of Benin. Surveys were conducted with a questionnaire and respondent were selected randomly in communities. A total of 360 informants were selected, 120 per district (40 users, 40 household and 40 key informants). The survey assessed residents’ perception of UGS with reference to key socioeconomic variables (age, gender, educational levels). Data were analyzed using Chi-square test, chordDiagram, correlations through corrplot packages and Principal Component Analysis under R software. It came out from this study, six positive aspects: shading, air pollutants absorption, aesthetics, recreation, medicinal uses and economic benefit and four incivility or negative aspects: waste dump, mosquito lodges, threat to roads and buildings cracking with roots. These benefits and disturbance inputted to trees differed significantly between the three cities (χ2 = 110.65; P <0.001) and three categories of interviewees (χ2 = 25.32; P = 0.004). Urban green spaces were also subject to anarchic exploitation which consisted of illegal logging, debarking, pruning, topping and root harvesting. This study allowed concluding that UGS plays an important socioeconomic role for surrounding communities. Therefore, it seems urgent to ensure the viability of these ecosystems. It also reported that communities expressed their will to participate in UGS protection and conservation

Understanding Coastal Citizens Perception on Urban Green Spaces: Evidence from Benin Republic in West Africa

Urban Green Spaces (UGS) have several benefits for humans and environment. Despite these numerous benefits and important roles, UGS are often disregarded because their ecosystem services are not quantified and well-understood in developing countries. Until now, no study was carried out regarding the local perception, urban green spaces use values, threats and management strategies in Benin. This study was undertaken to assess the importance of UGS to citizens’ communities, to identify threats to viability and communities’ commitment or willing to adhere participatory suitable management in three cities (Ouidah, Cotonou and Porto-Novo) located in the coastal area of Benin. Surveys were conducted with a questionnaire and respondent were selected randomly in communities. A total of 360 informants were selected, 120 per district (40 users, 40 household and 40 key informants). The survey assessed residents’ perception of UGS with reference to key socioeconomic variables (age, gender, educational levels). Data were analyzed using Chi-square test, chordDiagram, correlations through corrplot packages and Principal Component Analysis under R software. It came out from this study, six positive aspects: shading, air pollutants absorption, aesthetics, recreation, medicinal uses and economic benefit and four incivility or negative aspects: waste dump, mosquito lodges, threat to roads and buildings cracking with roots. These benefits and disturbance inputted to trees differed significantly between the three cities (χ2 = 110.65; P <0.001) and three categories of interviewees (χ2 = 25.32; P = 0.004). Urban green spaces were also subject to anarchic exploitation which consisted of illegal logging, debarking, pruning, topping and root harvesting. This study allowed concluding that UGS plays an important socioeconomic role for surrounding communities. Therefore, it seems urgent to ensure the viability of these ecosystems. It also reported that communities expressed their will to participate in UGS protection and conservation

Quantifying Street Tree Regulating Heat Effects Using a Generalized Linear Mixed Model Approach

Climate change has emerged as a significant global environmental concern, prompting increased interest in utilizing trees as an alternative means to enhance human well-being and thermal comfort in urban settings. This study endeavors to assess the influence of street trees on the urban microclimate in tropical cities, employing a Generalized Linear Mixed Model (GLMM) approach. The investigation was carried out in Cotonou, Porto-Novo, and Ouidah within Benin. Data collection was conducted along thoroughfares, where a systematic inventory was performed to measure various characteristics of each street tree, including crown shape, shade form on the ground, crown diameter, diameter at breast height, and tree height. Meteorological data, encompassing air temperature, relative humidity, and wind speed, were recorded at three different heights, thrice an hour from 7 am to 7 pm. Subsequently, these datasets were analyzed using GLMMs. A total of 1127 street trees belonging to 20 species and 13 families were identified. The Shannon Diversity Index and Pielou Equitability values ranged from 2.33 to 2.92 bits and 0.17 to 0.64, respectively. The GLMM analysis revealed that the presence of trees, daytime, and height significantly influenced air temperature, relative humidity, and wind speed. The presence of street trees on both sides of roadways induced an air temperature decrease ranging from -0.6°C to -1.4°C and an increase in relative humidity ranging from +2.5% to +5.2% between 11 am and 5 pm, as compared to other layouts. Furthermore, closed canopy patterns exhibited the most favorable outcomes, resulting in an air temperature decrease ranging from -0.4°C to -1°C and an increase in relative humidity ranging from +2.4% to +5.5% between 11 am and 5 pm. These findings hold the potential to inform urban planners and policymakers in designing and implementing effective street tree planting strategies that optimize cooling effects and mitigate the impact of climate change on urban areas

Quantifying Street Tree Regulating Heat Effects Using a Generalized Linear Mixed Model Approach

Climate change has emerged as a significant global environmental concern, prompting increased interest in utilizing trees as an alternative means to enhance human well-being and thermal comfort in urban settings. This study endeavors to assess the influence of street trees on the urban microclimate in tropical cities, employing a Generalized Linear Mixed Model (GLMM) approach. The investigation was carried out in Cotonou, Porto-Novo, and Ouidah within Benin. Data collection was conducted along thoroughfares, where a systematic inventory was performed to measure various characteristics of each street tree, including crown shape, shade form on the ground, crown diameter, diameter at breast height, and tree height. Meteorological data, encompassing air temperature, relative humidity, and wind speed, were recorded at three different heights, thrice an hour from 7 am to 7 pm. Subsequently, these datasets were analyzed using GLMMs. A total of 1127 street trees belonging to 20 species and 13 families were identified. The Shannon Diversity Index and Pielou Equitability values ranged from 2.33 to 2.92 bits and 0.17 to 0.64, respectively. The GLMM analysis revealed that the presence of trees, daytime, and height significantly influenced air temperature, relative humidity, and wind speed. The presence of street trees on both sides of roadways induced an air temperature decrease ranging from -0.6°C to -1.4°C and an increase in relative humidity ranging from +2.5% to +5.2% between 11 am and 5 pm, as compared to other layouts. Furthermore, closed canopy patterns exhibited the most favorable outcomes, resulting in an air temperature decrease ranging from -0.4°C to -1°C and an increase in relative humidity ranging from +2.4% to +5.5% between 11 am and 5 pm. These findings hold the potential to inform urban planners and policymakers in designing and implementing effective street tree planting strategies that optimize cooling effects and mitigate the impact of climate change on urban areas

Quantifying Street Tree Regulating Heat Effects Using a Generalized Linear Mixed Model Approach

Climate change has emerged as a significant global environmental concern, prompting increased interest in utilizing trees as an alternative means to enhance human well-being and thermal comfort in urban settings. This study endeavors to assess the influence of street trees on the urban microclimate in tropical cities, employing a Generalized Linear Mixed Model (GLMM) approach. The investigation was conducted in Cotonou, Porto-Novo, and Ouidah within Benin. Data collection was conducted along thoroughfares, where a systematic inventory was performed to measure various characteristics of each street tree. Meteorological data, encompassing air temperature, relative humidity, and wind speed, were recorded at three different heights thrice an hour from 7 a.m. to 7 p.m. Subsequently, these datasets were analyzed using GLMMs. A total of 1127 street trees belonging to 20 species and 13 families were identified. The Shannon Diversity Index and Pielou Equitability values ranged from 2.33 to 2.92 bits and 0.17 to 0.64, respectively. The GLMM analysis revealed that the presence of trees, daytime, and height significantly influenced air temperature, relative humidity, and wind speed. Street trees on both sides of roadways induced an air temperature decrease from -0.6°C to -1.4°C and an increase in relative humidity ranging from +2.5% to +5.2% between 11 am and 5 pm, as compared to other layouts. Furthermore, closed canopy patterns exhibited the most favorable outcomes, resulting in an air temperature decrease from -0.4°C to -1°C and an increase in relative humidity from +2.4% to +5.5% between 11 am and 5 pm

Composition floristique et potentiel fourrager des principaux ligneux des parcours d’accueil des transhumants dans la Basse et Moyenne Vallée de l’Ouémé en zone guinéo-soudanienne du Bénin

Objectifs: Les ligneux fourragers constituent une ressource alimentaire dans la zone d’accueille des bovins transhumants en saison sèche. L’objectif de cette étude était d’inventorier les ligneux fourragers des parcours des transhumants de la Basse et Moyenne Vallée de l’Ouémé, d’évaluer leur contribution pour l'alimentation des bovins transhumants en saison sèche et d’analyser leurs modes d’utilisation en vue de l'amélioration de la gestion de l'écosystème.Méthodologie et Résultats: Des suivis des troupeaux au pâturage ont été effectués pour identifier les principaux ligneux fourragers. Les mesures sur les ligneux ont été réalisées dans 181 placeaux de 50 m X 50 m installées au hasard selon le type de sol et de végétation. La méthode non destructive été a utilisée pour évaluer la biomasse foliaire. Pterocarpus santalinoides (Teck africain), Kigelia africana (Saucissonier), Lonchocharpus sericeus (Lilas du Sénégal) Mitragyna inermis (Pied d’éléphant), Daniellia oliveri (baumier d’Ilorin) et Vitex doniana (Prunier noir) étaient les ligneux présentant un grand intérêt pastoral. La biomasse foliaire a varié de 5 à 346,90 kg MS / ha et la capacité de charge de 0,003 à 0,185 unité de bétail tropical par hectare. Le mode d'exploitation des ligneux est basé sur l'élagage des branches et l'abattage.Conclusions et application des résultats: La présente étude a montré que les ligneux fourragers tels que D. oliveri, K. africana, L. sericeus, M. inermis, P. santalinoides et V. doniana sont prioritaires pour l'alimentation des bovins transhumants pendant la saison sèche. Cependant, les modes d'utilisation et le surpâturage compromettent leur régénération naturelle. Il est nécessaire d'améliorer la gestion durable des pâturages afin de continuer à alimenter le bétail pendant la saison sèche. Il est également important de développer des moyens efficaces de régénération de ces espèces ligneuses en utilisant des politiques de gestion participative des ressources mises en oeuvre pour assurer la durabilité des services sociaux et pastoraux.Mots clés: ligneux fourragers, caractéristique structurale, biomasse foliaire, capacité de charge, végétation, BéninEnglish Title: Floristic composition and forage potential of the main tree fodder of transhumant rangeland in the Lower and Medium Oueme Valley in the Guineo-Sudanean zone of BeninEnglish AbstractObjectives: Tree forage is a feed resource in area receiving the transhumant ruminants, during the dry season. The objective of this study was to inventory fodder trees of the rangelands of the Lower and Mean Valley of Oueme, to evaluate their contribution to animal feeding and to analyze the modes of use in order for better management of the ecosystem.Methodology and Results: Grazing surveys were conducted to identify the main forage trees. The data were collected in 181 plots of 50 m X 50 m installed randomly according to type of soil and vegetation. The nondestructive method was used to evaluate tree leaf biomass. Fodder tree plants such as Pterocarpussantalinoides (African teak), Kigelia africana (Sausage tree), Lonchocharpus sericeus (Senegal lilac) Mitragyna inermis(Elephant foot), Daniellia oliveri (West African copal) and Vitex doniana (Black plum tree) have shown great pastoral interest. Leaf biomass varied from 5 to 346.90 kg MS / ha and carrying capacity from 0.003 to 0,185 Tropical Livestock Unit per ha. The mode of use of the trees leaves is based on the pruning of the branches and the felling.Conclusions and application of findings: The present study showed that the fodder trees such as D. oliveri, K. africana, L. sericeus, M. inermis, P. santalinoides, and V. doniana are priorities for rangelands feeding during dry season by transhumant farmer. However, the modes of use and the overgrazing of trees, compromise their natural regeneration. There is a need to improve sustainable management of rangelands in order to continue to feed the cattle during the dry season. So, it’s also important to develop effective means of regeneration of these woody species by using participatory resource management policies implemented to ensure sustainability of social and pastoral services.Keywords: Ligneous forage, structural characteristic, leaf biomass, carrying capacity, vegetation, Beni

Diversité floristique, structure et distribution des groupements végétaux des parcours d’accueil des transhumants dans la Basse et Moyenne Vallée de l’Ouémé au Bénin

La perte de la biodiversité végétale, liée à la dégradation des parcours est l’un des défis pour les pays d’accueil des transhumants. La présente étude visait à analyser les caractéristiques structurales et la diversité floristique des groupements végétaux dans la Basse et Moyenne Vallée de l’Ouémé (BMVO). Les données phytosociologiques, collectées dans 113 relevés selon la méthode de Braun-Blanquet (1932), ont été soumises à une DCA avec le logiciel R 3.3.2. Ainsi, 173 espèces regroupées dans 127 genres et 45 familles ont été  recensées. Au total, 4 groupements végétaux ont été identifiés : les groupements GI à Andropogon gayanus var squamulatus et Mitragyna inermis ; GII à Paspalum notatum et Aeollanthus pubescens ; GIII à Panicum maximum et Calopogonium mucunoides et le groupement végétal GIV à Tridax procumbens et Daniellia oliveri. La diversité floristique est liée à la topographie, la nature du sol et son humidité, et l’intensité d’exploitation des terres. Les thérophytes et les phanérophytes ont été les plus abondants dans tous les groupements. Par contre, les hémicryptophytes ont été plus dominants dans le groupement GI. Les espèces à large distribution et à distribution continentale ont été plus abondantes et dominantes dans tous les groupements. Cette recherche servira de base pour l’analyse de la dynamique de la végétation des terres de parcours de la BMVO. Mots clés : Parcours, facteurs écologiques, types biologiques, types phytogéographiques, Bénin