Freshwater bodies are natural resources that should be exploited to the fullest, while maintaining the sustainability of ecosystems and ecosystem services which they support. Riparian forests are more important as the...Freshwater bodies are natural resources that should be exploited to the fullest, while maintaining the sustainability of ecosystems and ecosystem services which they support. Riparian forests are more important as they contain rivers which are vital sources of fresh water for local populations. However, the quality and quantity of water issued from the watershed depend on the structural state of these forests. The aim of this work was to assess the physico-chemical and structural state of the Akono gallery forest. To achieve this, fieldwork consisted of selecting six major streams of the watershed including Ndjolong, Menyeng adzap, Emomodo, Mvila, Negbe and Ossoé kobok. On each of these, two stations, one intact and one degraded, were marked by transects. The method involved measuring Hydrometric parameters (depth, length, width) of the stream and Physico-chemical parameters of water in the streams while dendrometric parameters were measured along 100 m-transects laid using the point-centred quarter method modified for water bodies to collect tree, shrub and palm variables such as trunk diameter, crown diameter and height. Macrophytes and species identification were carried out using standard botanical procedures. Results showed that, the majority of physico-chemical parameters measured differed significantly between intact and degraded stations (P Pentachletra mancrophylla, whereas on degraded sites, this index was low and characterized by the relative dominance of species Piptadeniastrum africanum. Sorensen’s index (0.56) and CFA showed that the different stands were homogeneous. We can affirm that the riparian forests of Akono watershed are towards a state of stability notwithstanding the perpetuation of anthropological actions.展开更多
Prunus africana is a species of great economic, medicinal and ecological importance. Due to its multiple uses, unsustainable exploitation methods and low regeneration capacity in tropical rainforests, this species is ...Prunus africana is a species of great economic, medicinal and ecological importance. Due to its multiple uses, unsustainable exploitation methods and low regeneration capacity in tropical rainforests, this species is threatened with extinction. Present and exploited in the eastern part of DR Congo, knowledge of the dynamics of post-bark regeneration of Prunus africana remains fragmentary and poorly known. In North Kivu province, this species thrives in both afromontane forest and lowland tropical rainforest habitats. In order to contribute to the rational and sustainable exploitation of Prunus africana in this province, this paper was carried out with the objective of contributing to the knowledge of the dynamics of the regeneration of post-harvest bark of Prunus africana in two exploitation sites (low and high altitude). To achieve this objective, the inventory was conducted on 16 plots of 25 hectares each, with 8 plots per site. Dendrometric parameters (diameter at breast height (DBH), total tree height) and tree growth and regeneration parameters, i.e., stem bark thickness of the unharvested and harvested portions of the trees (bark reconstitution) were measured. A total of 716 barked stems of Prunus africana in 2016 in 25 hectares constituted the study sample. Results show that sites do not influence diameter at breast height of P. africana trees (p > 0.05) or total tree height. The bark diameter of harvested trees and the bark diameter of unharvested trees varied significantly by site (p 0.05). In contrast, the annual growth rate of bark differed with altitude;the highest rate was observed in trees growing at high altitude (2.97 ± 0.9 mm/yr) compared to 2.23 ± 0.74 mm/yr at low altitude. In view of these results, this study indicates that a half-rotation of 7 years could allow an effective reconstitution of the bark of Prunus africana at the second passage on the remaining side of the same stem.展开更多
文摘Freshwater bodies are natural resources that should be exploited to the fullest, while maintaining the sustainability of ecosystems and ecosystem services which they support. Riparian forests are more important as they contain rivers which are vital sources of fresh water for local populations. However, the quality and quantity of water issued from the watershed depend on the structural state of these forests. The aim of this work was to assess the physico-chemical and structural state of the Akono gallery forest. To achieve this, fieldwork consisted of selecting six major streams of the watershed including Ndjolong, Menyeng adzap, Emomodo, Mvila, Negbe and Ossoé kobok. On each of these, two stations, one intact and one degraded, were marked by transects. The method involved measuring Hydrometric parameters (depth, length, width) of the stream and Physico-chemical parameters of water in the streams while dendrometric parameters were measured along 100 m-transects laid using the point-centred quarter method modified for water bodies to collect tree, shrub and palm variables such as trunk diameter, crown diameter and height. Macrophytes and species identification were carried out using standard botanical procedures. Results showed that, the majority of physico-chemical parameters measured differed significantly between intact and degraded stations (P Pentachletra mancrophylla, whereas on degraded sites, this index was low and characterized by the relative dominance of species Piptadeniastrum africanum. Sorensen’s index (0.56) and CFA showed that the different stands were homogeneous. We can affirm that the riparian forests of Akono watershed are towards a state of stability notwithstanding the perpetuation of anthropological actions.
文摘Prunus africana is a species of great economic, medicinal and ecological importance. Due to its multiple uses, unsustainable exploitation methods and low regeneration capacity in tropical rainforests, this species is threatened with extinction. Present and exploited in the eastern part of DR Congo, knowledge of the dynamics of post-bark regeneration of Prunus africana remains fragmentary and poorly known. In North Kivu province, this species thrives in both afromontane forest and lowland tropical rainforest habitats. In order to contribute to the rational and sustainable exploitation of Prunus africana in this province, this paper was carried out with the objective of contributing to the knowledge of the dynamics of the regeneration of post-harvest bark of Prunus africana in two exploitation sites (low and high altitude). To achieve this objective, the inventory was conducted on 16 plots of 25 hectares each, with 8 plots per site. Dendrometric parameters (diameter at breast height (DBH), total tree height) and tree growth and regeneration parameters, i.e., stem bark thickness of the unharvested and harvested portions of the trees (bark reconstitution) were measured. A total of 716 barked stems of Prunus africana in 2016 in 25 hectares constituted the study sample. Results show that sites do not influence diameter at breast height of P. africana trees (p > 0.05) or total tree height. The bark diameter of harvested trees and the bark diameter of unharvested trees varied significantly by site (p 0.05). In contrast, the annual growth rate of bark differed with altitude;the highest rate was observed in trees growing at high altitude (2.97 ± 0.9 mm/yr) compared to 2.23 ± 0.74 mm/yr at low altitude. In view of these results, this study indicates that a half-rotation of 7 years could allow an effective reconstitution of the bark of Prunus africana at the second passage on the remaining side of the same stem.
