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Le nord-ouest du Togo, est caractérisé par une forte pression sur les sols, entrainant une régression de parcs agroforestiers et une diminution rendements agricoles. Dans un tel milieu, l’appréciation des producteurs de ces changements ainsi que les méthodes qu’ils adoptent pour y faire face restent moins connus. C’est pour cet objectif qu’une enqu...
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... Si l'on s'attache aux éléments climatiques, 40% des agriculteurs enquêtés indiquent que les températures ont augmenté et que les pluies sont plus rares et les périodes de déficit hydrique pour les cultures se sont allongées. Les plus instruits évoquent des conséquences en termes d'ensablement de cours d'eau alimentant le plateau irrigué, de baisse des rendements et d'accélération de la dégradation des sols comme le stipulent les travaux deMagamana et al. (2021). Les versants (37,5%) sont exploités sans structures antiérosives. ...
En vue d’évaluer l’impact des pratiques agricoles sur les sols, les approches d’expérimentation de longue durée et de simulation à partir de modèles numériques sont de plus en plus fréquentes. Cependant, dans le contexte des pays du Sud, elles sont souvent difficiles à mettre en œuvre, faute de moyens. Cette étude avait pour objectif de décrire la diversité des systèmes (SC) de culture rencontrés dans une petite région d’altitude d’Haïti, afin d’utiliser ces connaissances, pour raisonner dans une deuxième étape, un dispositif d’évaluation « on-farm » de leurs effets sur les sols. Le concept de système de culture met en avant les interactions fortes existant entre les décisions techniques que prennent les agriculteurs sur leurs parcelles, aussi bien en termes de successions et associations culturales, de gestion de leur disponibilité en nutriments et en eau, et de contrôle des bioagresseurs des cultures. Notre étude s’était appuyée sur 78 parcelles d’agriculteurs sélectionnées avec l’aide de personnes ressources de la région, pour représenter la diversité des unités pédo- bioclimatiques. Chaque parcelle a fait l’objet d’une enquête auprès de son exploitant en vue de décrire ses choix techniques de ces 10 dernières années. On a mis en évidence la coexistence de quatre systèmes de culture (SC) : un système intensif (SI), un système semiintensif (SSI), un système agroforestier (SA) et un système de pâturage permanent (SSU). Ils étaient répartis suivant le pédoclimat avec le SI dominant dans le périmètre irrigué, le SSI dans le plateau non irrigué, le SA dans les vallées et le SSU dans les versants. Le labour n’était absent qu’en SSU. Les indicateurs de ces systèmes étaient facilement accessibles et peuvent être mobilisés en vue de raisonner un dispositif d’évaluation des performances agro-environnementales des pratiques des agriculteurs et concevoir des améliorations de gestion. English title: Legumes, Agroforestry, ploughing and pasture: determinants of the cropping systems diversity in Saint-Raphael, Haiti In order to assess the impact of agricultural practices on soils, long-term experimental and simulation approaches based on numerical models are becoming increasingly common. However, in the context of Southern countries, they are often difficult to implement due to lack of financial resources. The objective of this study was to describe the diversity of cropping systems (SC) encountered in a small highland region of Haiti, in order to use this knowledge to reason, in a second step, an "on-farm" evaluation system of their effects on soils. The concept of cropping systems highlights the strong interactions between the technical decisions that farmers make on their plots, both in terms of crop succession and associations, management of nutrient and water availability, and control of crop pests. Our study was based on 78 farmers' plots selected with the help of resource persons in the region, to represent the diversity of soil- bioclimatic units. Each plot was surveyed to describe the technical choices made by the farmer over the last 10 years. Four cropping systems (SC) were found to coexist: an intensive system (SI), a semi-intensive system (SSI), an agroforestry system (SA) and a permanent pasture system (SSU). They were distributed according to the pedoclimate, with the SI system dominating in the irrigated perimeter, the SSI system in the non-irrigated plateau, the SA system in the valleys and the SSU system on the slopes. Plowing was absent only in SSU. The indicators of these systems were easily accessible and can be used to reason out an evaluation system of the agro-environmental performance of farmers' practices and to design management improvements.
... Farmers face the challenges of climate change, biodiversity loss, and food insecurity. Against this backdrop, more attention needs to be paid to ecosystem stability by implementing agroecological restoration projects to achieve the Sustainable Development Goals [8]. ...
In the context of climate change, the need to contribute to achieving Sustainable Development Goal (SDG) 2 is no longer in doubt, especially in sub-Saharan Africa. In this study of the landscape within 10 km of the Donomadé model farm, southeastern Togo, researchers sought to assess vegetation health in ecosystems and agrosystems, including their capacity to produce biomass for agroecological practices. Sentinel-2 sensor data from 2015, 2017, 2020, and 2022 were preprocessed and used to calculate the normalized vegetation fire ratio index (NBR), the vegetation fire severity index (dNBR), and CASA-SEBAL models. From these different analyses, it was found that vegetation stress increased across the landscape depending on the year of the time series. The research estimated that 9952.215 ha, 10,397.43 ha, and 9854.90 ha were highly stressed in 2015, 2017, and 2020, respectively. Analysis of the level of interannual severity revealed the existence of highly photosynthetic areas that had experienced stress. These areas, which were likely to have been subjected to agricultural practices, were estimated to be 8704.871 ha (dNBR2017-2015), 8253.17 ha (dNBR2020-2017), and 7513.93 ha (dNBR2022-2020). In 2022, the total available biomass estimated by remote sensing was 3,741,715 ± 119.26 kgC/ha/y. The annual average was 3401.55 ± 119.26 kgC/ha/y. In contrast, the total area of healthy vegetation was estimated to be 4594.43 ha, 4301.30 ha, and 4320.85 ha, in 2015, 2017, and 2022, respectively. The acceptance threshold of the net primary productivity (NPP) of the study area was 96%. The coefficient of skewness (0.81 ± 0.073) indicated a mosaic landscape. Productive and functional ecosystem components were present, but these were highly dispersed. These findings suggest a great opportunity to promote agroecological practices. Mulching may be an excellent technique for enhancing overall ecosystem services as targeted by the SDGs, by means of reconversion of plant biomass consumed by vegetation fires or slash-and-burn agricultural practices.
The ecosystem-based adaptation (EbA) strategy is considered an effective approach to address the impact of climate change while ensuring the continued provision of ecosystem services on which farming depends. However, understanding the EbA's effectiveness for smallholder farmers in the Savannah region remains limited. The focus of this study is to explore the EbA practices that have been implemented by farming communities in the Savannah region of Togo. The study aims to evaluate the effectiveness of these practices and the perceived co-benefits reported by 425 smallholder farmers who participated in the survey. Our findings show that five practices, namely agroforestry, crop rotation, grass hedge/stone bunds, in-field water drainage channel, and intercropping, were practiced mainly by smallholder farmers and perceived as effective in reducing their vulnerability to climate risks. In addition, the benefits observed were linked to all five EbA practices. As a result, we can determine the suitable combination of EbA practices that fulfil the requirements of smallholder farmers, including co-benefits such as food security, adaptation advantages, and ecosystem service provisions. Such findings provide insights for developing integrated agriculture and climate change policies suitable for weather-induced disaster-prone areas such as the Savannah region.
