[ Ptéridophytes : Bio indicateurs des changements opérés sur la structure des forêts de zone de montagnes du Parc National de Kahuzi-Biega à l'Est de la R.D. Congo ]
Volume 16, Issue 2, July 2015, Pages 350–370
Jean de Dieu MANGAMBU MOKOSO1, François MUHASHY2, Elmar ROBBRECHT3, THOMAS JANSSEN4, Honorine NTAHOBAVUKA HABIMANA5, and Van DIGGELEN RUURD6
1 Département de Biologie, Laboratoire de Systématique Végétale et de Biodiversité, Faculté des Sciences et sciences Appliquées, Université Officielle de Bukavu, RD Congo
2 Institut Royal des Sciences naturelles de Belgique, Rue Vautier 29B, Bruxelles 1000, Belgium
3 Departement of Biologie, Universiteit Antwerp, Universiteitsplein 1-C, B-2610 Antwerp-Wilrijk, Belgium
4 Institut für Biologie, Humboldt-Universität zu Berlin, Unter den Linden 6 10099 Berlin, Germany
5 Département d'Ecologie et Gestion des Ressources Végétales, Laboratoire de Palynologie, Anatomie du bois et biodiversité forestière, R.D. Congo, Faculté des Sciences, Université de Kisangani, B.P : 2012 Bukavu, RD Congo
6 Departement of Biologie, Universiteit Antwerp, Universiteitsplein 1-C, B-2610 Antwerp-Wilrijk, Belgium
Original language: French
Copyright © 2015 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Though the national Kahuzi-Biega Park be necessarily covered with a forest of well distinguished canopy; it also possesses disturbed areas. This work aims at studying the floristic composition of Ferns and Fern Allies to assess vegetation disturbances in the mountain forests (ranging from 1250 meters to 3000 meters) within the Kahuzi-Biega National Park. Comparisons of vegetation features were made both in disturbed and non-disturbed habitats. Data were collected within 24 plots differently located following the 3 vegetation altitudinal ranges (submontane, montane, afro-alpine) taken into account. In each plot, 4 sampling units of 1ha each were established. Collected data included abundance and dominance features of plant species (both Ferns and their Allies, as well as woody species), tree diameter (DBH), and canopy height, the average of vegetation cover per forest layer (stratum) as well as floristic patterns and species richness. We referred to CANOCO and R (version 2.10.1) softwares to perform our statistical analyses. Results showed that the 3 altitudinal ranges offer differences in their floristic composition. The considered plant features (height, diametric structure) also express variations when disturbed and non-disturbed habitats are taken into consideration. This is for example illustrated by significant differences (results based on a t-test, p-value = 0.007) when one considers the occurrence of Ferns and their Allies. Within stable habitats, Ferns and their Allies particularize themselves by rich and much diversified communities. However, disturbed habitats (following various causes of permanent aggression) face major changes into the floristic composition of their major canopy tree species.
Author Keywords: Ferns, Fern Allies, Bio-indicators, Forest Structure, Kahuzi-Biega National Park.
Volume 16, Issue 2, July 2015, Pages 350–370
Jean de Dieu MANGAMBU MOKOSO1, François MUHASHY2, Elmar ROBBRECHT3, THOMAS JANSSEN4, Honorine NTAHOBAVUKA HABIMANA5, and Van DIGGELEN RUURD6
1 Département de Biologie, Laboratoire de Systématique Végétale et de Biodiversité, Faculté des Sciences et sciences Appliquées, Université Officielle de Bukavu, RD Congo
2 Institut Royal des Sciences naturelles de Belgique, Rue Vautier 29B, Bruxelles 1000, Belgium
3 Departement of Biologie, Universiteit Antwerp, Universiteitsplein 1-C, B-2610 Antwerp-Wilrijk, Belgium
4 Institut für Biologie, Humboldt-Universität zu Berlin, Unter den Linden 6 10099 Berlin, Germany
5 Département d'Ecologie et Gestion des Ressources Végétales, Laboratoire de Palynologie, Anatomie du bois et biodiversité forestière, R.D. Congo, Faculté des Sciences, Université de Kisangani, B.P : 2012 Bukavu, RD Congo
6 Departement of Biologie, Universiteit Antwerp, Universiteitsplein 1-C, B-2610 Antwerp-Wilrijk, Belgium
Original language: French
Copyright © 2015 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
Though the national Kahuzi-Biega Park be necessarily covered with a forest of well distinguished canopy; it also possesses disturbed areas. This work aims at studying the floristic composition of Ferns and Fern Allies to assess vegetation disturbances in the mountain forests (ranging from 1250 meters to 3000 meters) within the Kahuzi-Biega National Park. Comparisons of vegetation features were made both in disturbed and non-disturbed habitats. Data were collected within 24 plots differently located following the 3 vegetation altitudinal ranges (submontane, montane, afro-alpine) taken into account. In each plot, 4 sampling units of 1ha each were established. Collected data included abundance and dominance features of plant species (both Ferns and their Allies, as well as woody species), tree diameter (DBH), and canopy height, the average of vegetation cover per forest layer (stratum) as well as floristic patterns and species richness. We referred to CANOCO and R (version 2.10.1) softwares to perform our statistical analyses. Results showed that the 3 altitudinal ranges offer differences in their floristic composition. The considered plant features (height, diametric structure) also express variations when disturbed and non-disturbed habitats are taken into consideration. This is for example illustrated by significant differences (results based on a t-test, p-value = 0.007) when one considers the occurrence of Ferns and their Allies. Within stable habitats, Ferns and their Allies particularize themselves by rich and much diversified communities. However, disturbed habitats (following various causes of permanent aggression) face major changes into the floristic composition of their major canopy tree species.
Author Keywords: Ferns, Fern Allies, Bio-indicators, Forest Structure, Kahuzi-Biega National Park.
Abstract: (french)
Bien que le Parc National de Kahuzi-Biega (PNKB) soit essentiellement couvert par une forêt à canopée bien distincte. Il possède aussi des milieux perturbés. Ce papier s'intéresse à la composition floristique des Ptéridophytes pour tester les perturbations sur la structure de végétation qui s'opèrent dans la zone des montagnes du PNKB. Nous avons réalisé des comparaisons entre deux types de milieux (perturbés et non perturbés) rencontrés sur la végétation qui s'échelonne entre 1250 à 3300 mètres d'altitude. Les données utilisées ont été récoltées dans 24 placettes à raison de huit placettes pour chacun des trois étages étudiés parmi lesquelles quatre ont subi une perturbation anthropique ou naturelle et quatre autres sont non perturbées. L'étude a été évaluée grâce à quatre relevés effectués dans chaque placette d'un hectare pour prélever les données d'abondance-dominance des espèces (Ptéridophytes, arbres et arbustes), la classe de diamètre (arbre et arbustes), la hauteur de la canopée, le recouvrement moyen par strate et la richesse floristique des arbres, arbustes et Ptéridophytes. Nous avons analysé et comparé la richesse des cormophytes en utilisant les logiciels CANOCO et R (version 2.10.1). Les résultats obtenus confirment une variation de la composition floristique dans les trois étages. La différence de la hauteur, distribution diamétrique (arbres et arbustes) et la présence des Ptéridophytes entre les milieux non perturbés et perturbés est très significative (test t, p-value = 0,007). Dans les parcelles stables, c'est-à-dire dans l'écosystème stable et mature, les Ptéridophytes constituent un peuplement très riche, diversifié. Une agression permanente se montre dans des parcelles perturbées et se traduit par une modification de la composition floristique de canopée et parfois l'apprivoisement du sous-bois.
Author Keywords: Ptéridophytes, bio-indicateurs, structure des forêts, Parc National de Kahuzi-Biega.
How to Cite this Article
Jean de Dieu MANGAMBU MOKOSO, François MUHASHY, Elmar ROBBRECHT, THOMAS JANSSEN, Honorine NTAHOBAVUKA HABIMANA, and Van DIGGELEN RUURD, “Ferns and Fern Allies: Bio indicators of changes occurred in the structure of the mountain forests within the Kahuzi-Biega National Park in eastern D.R. Congo,” International Journal of Innovation and Scientific Research, vol. 16, no. 2, pp. 350–370, July 2015.
