Djibrim ABDOULAYE

Abdou Moumouni University

PhD topic: Population dynamics and assessment of the carbon stock of Borassus aethiopum Mart.: case of the agroforestry park based on Borassus of Dallol Maouri, Gaya/Niger

Summary: This study focused on the population dynamics and assessment of the carbon stock of Borassus aethiopum Mart. : Case of the agroforestry park based on Borassus of Dallol Maouri, Gaya/ Niger.The insufficiency or even lack of information on the largest Borassus population in Niger, which has received particular attention from local authorities and development partners since the 1980s following its degradation and has since been subjected to planting as part of its restoration, is the main motivation for this research. To this end, a series of methods, such as remote sensing techniques (i), forest inventory (ii), carbon quantification by the Borassus allometric equation established for this purpose (iii) and a socio-economic survey (iv) were used. The diachronic study using remote sensing revealed that between 1987 and 2022, the parkland experienced a net increase of nearly 1,000 hectares in areas with medrate and high Borassus density and over 1,500 hectares in flood zones. However, the latter began to expand significantly from 2003 onwards, at the expense of the former two zones. According to the forest inventory, the species richness of this stand is moderate (Margalef index = 4.27), and Borassus, with an importance value index of 203%, is the largest dominant species among the 35 recorded species, distributed among 20 families. Across the five sub-parks that form the Dallol Maouri park, the diametrical structure of Borassus is bell-shaped, with Weibull shape parameter values ranging from 2.8 to 4.7. The sub-parks with high density are Bana and Tousseye, with 26 and 42 Borassus trees per hectare, respectively. Furthermore, the carbon sequestration study reveals that the amount of carbon contained in the aboveground biomass of Borassus averages 53.4%. The allometric equation for this biomass is defined by a synthetic variable including diameter and total height. Thus, the estimated amount of carbon stored exclusively by Borassus in its aboveground biomass is approximately 87,957tons. For the socio-economic aspect, the study showed that Borassus contributes on average 11% to household agricultural income, an amount ranging from €0 to €1,372, primarily from the sale of the hypocotyl. All parts of this palm are used in various ways in the region, but certain practices, such as logging and illegal harvesting of its leaves are becoming increasingly concerning. In sum, the Dallol Maouri palm grove has undergone remarkable restoration over the past 35 years and plays an important socio-economic and environmental role. However, flooding and certain human practices in recent times threaten this resource.

Supervisor(s) name(s): Pr. Larwanou MAHAMANE, Dr. Martin Wiehle

Area of interest: Agroforestry

Educational background: 

  • 2013: Complementary Master in Management of Animal and Plant Resources in Tropical Environments. Faculty of Veterinary Medicine / University of Liège/ BELGIUM.
  • 2011: Master II in Territory, Resources and Rural Development Strategy Option: Agroforestry. Faculty of Agronomy /Abdou Moumouni University of Niamey/ NIGER.
  • 2007: Master’s degree in Agricultural Sciences. Faculty of Agronomy /Abdou Moumouni University of Niamey/ NIGER.
  • 2004: University Diploma of Scientific Studies. Faculty of Sciences / Abdou Moumouni University of Niamey.

Professional experience: 

  • 2014–2022: Assistant, then Head of the Publication and Data Dissemination Division / Statistics Department / Ministry of the Environment, Urban Sanitation and Sustainable Development / Niamey / Niger;
  • 2014: General Supervisor at the Concerted Action Research Unit in Natural Resource Management (CRAC-GRN) /SOS Sahel International /Zinder/Niger

Awards/scholaships: 

  •  2021: Scholarship of the German Academic Exchange Service (DAAD) funded through the framework of Project ‘Promoting Academic Capacities for Sustainable Agricultural Resources Use in West Africa’ (Pro-RUWA), Project ID 57587014.
  • 2012: Scholarships of the Belgian Technical Cooperation (BCT).

Primary research keywords: Borassus aethiopum, Dallol Maouri, evolution, floristic composition, carbon sequestration,  agricultural income

Email address:djibrim22[at]yahoo[dot]fr