Dynamique de la densité du « bambou de chine » et approvisionnement de la ville de Yaoundé

Abstract

The development of the commercialization of Chinese bamboo in the city of Yaoundé leads to a decline in the densities of the resource. This situation results in the unavailability of the product in production sites and in turn in points of sale. It is therefore a question in the present work, to highlight the evolution of the densities of Chinese Bamboo in the context of supply of the city of Yaoundé. We opted for a hypothetical-deductive approach, focused mainly on the consideration of structural characteristics (densities, age, stem diameter) as an indicator of the strong anthropization of The Chinese Bamboo forests in the geographical space of the supply of the city of Yaoundé. To do this, we carried out inventories through six plots in two types of bamboo forests in China (those exploited (3) and those not exploited (3)). In each plot (100m2 circular) each rod has been measured for its dendrometric characteristics. In addition, we conducted a survey on a sample of 91 individuals (producers, collectors, transporters, retail wholesalers) obtained from the non-probability sampling method, the snowball in the city of Yaoundé and in the selected production sites (Akono, Ngoumou, Mbankomo).The surveys show that 97.7% of the actors in the sector today denote a scarcity of the product in the production sites compared to 2021 when 80% rather noted a high availability of the resource. The data collected in all the plots show that there are 17,766 stems/ha in the forest area. Between the unexploited clumps and those that have been exploited, there is a difference of 8700 stems/ha or 32.87% of cut stems out of the initial total estimated at approximately 26466 stems/ha. In the felling sites, we went from a situation of 5033 stems/ha (≥ 3 years and 8 cm on average in diameter) to only 300 stems/ha. 76.46% of the stems are between 1 and 2 years old. Only 23.54% of stems are ≥ 3 years old. This is 89.03% of the total stems of the tufts exploited per hectare have between 4 cm and 6 cm in diameter. This regression of the structural parameters results in a reduction of the carbon stock potential. There is a difference of 2.11 t/ha between the exploited (3.111 t/ha) and unexploited clumps (1.001 t/ha). With regard to the potential of CO2 sequestered by aerial biomass, there is a regression in the quantities of CO2, there is a difference of 7.737 t per hectare of CO2 stock between the clumps exploited (3.673 t/ha) and not exploited (11.41 t/ha).