scholarly journals Vegetation Dynamics in Treeline Ecotone of Langtang National Park, Central Nepal

1970 ◽  
Vol 11 ◽  
pp. 107-114 ◽  
Author(s):  
NP Gaire ◽  
YR Dhakal ◽  
HC Lekhak ◽  
DR Bhuju ◽  
SK Shah
Keyword(s):  
Tree Species ◽  
National Park ◽  
Basal Area ◽  
Anthropogenic Pressure ◽  
Climatic Warming ◽  
Seedling Density ◽  
Treeline Ecotone ◽  
Central Nepal ◽  
Abies Spectabilis ◽  
The Impact

A study was carried out at the treeline ecotone (3,730m-3,950m asl) of Langtang National Park in central Nepal with an aim to document the impact of climatic warming on ecological chracteristics. Three sampling sites were selected at Chaurikharka and Lauribina, where no serious anthropogenic pressure was noticed. The nearest meteorological station has records of climatic warming in recent years. Six tree species and three shrub species belonging to seven families were enumerated from the study plots. The average basal area for tree species was found to be 20.56 m2 per ha while average tree density was found to be 734 trees per ha with Abies spectabilis as dominant species. The mean DBH (diameter at breast height) of tree species was found to be 15.8 cm (max. 115.5cm). Density of dead trees accounted 2 no. per ha with basal area 0.195m2 per ha. Average sapling and seedling density of tree species per ha was observed to be 1,590 and 831 respectively. The average sapling and seedling density of A. spectabilis was 255 and 350 per ha respectively. Similarly, average shrub density (per ha) for the area was found to be 9,609 no/ha. The stand character showed that there was high level of recruitment of A. spectabilis in the recent years. The presence of sapling and seedling of A. spectabilis at higher altitude showing linear relationship with canopy coverage indicated prospects for a gradual and upward shift of A. spectabilis with increased temperature. Key words: Abies spectabilis; regeneration; climate change; DBH DOI: 10.3126/njst.v11i0.4132Nepal Journal of Science and Technology 11 (2010) 107-114

scholarly journals Vegetation Composition and Biomass Production in Community Forest in Sikre VDC adjoining Shivapuri National Park, Kathmandu

1970 ◽  
Vol 11 ◽  
pp. 133-138
Author(s):  
Sudip Pandey ◽  
Siddhartha Bajra Bajracharya
Keyword(s):  
Tree Species ◽  
National Park ◽  
Basal Area ◽  
Sampling Technique ◽  
Shannon Index ◽  
Systematic Sampling ◽  
Anthropogenic Pressure ◽  
Community Forest ◽  
Eupatorium Adenophorum ◽  
Castanopsis Indica

The present study describes the structural and floral composition of the vegetation of Sikre Village Development Committee (VDC) at Shivapuri National Park. Systematic sampling technique was used to analyze the vegetation of the forest. A quadrat size of 10mx10m was plotted at respective point for tree study and within 5mx5m plots for shrubs and 1mx1m for herbs analysis. The study recorded a total of 18 tree species from 13 families in the forest area. Among the trees, Uttis (Alnus nepalensis D. Don) and Chilaune [Schima wallichii (DC.) Korth.] were the most dominant species. The major shrubs of the forest areas comprised of Yurilo (Hypericum uralum Buch.-Ham. ex D. Don), Chutro (Berberis aristata DC.) and Angeri (Melastoma melabathricum L.). Among the herbs Bhui Amala (Phyllanthus freternus Webster), Unyu [Dryopteris filix-mas (L.) Schott.] and Banmara (Eupatorium adenophorum Spreng.) were dominant ones in forest ground. The aboveground biomass of tree species was found to be 4021.41kg/ha in which Dhalne katus [Castanopsis indica (Roxb.) Miq.] constituted the large percent of biomass of the forest. The estimated resources demand and supply showed the annual deficit of 112.038t/yr and the carbon stock was calculated to be 2.01t/ha. The Shannon Index of diversity was highest for tree (2.33) followed by shrub (2.22) and herb (2.17) respectively. The density of cut stumps and the density of lopping were 184/ha and 216/ha respectively, which showed that the anthropogenic pressure on community forest was prominent. Key words: basal area; biomass; species diversity; systematic sampling DOI: 10.3126/njst.v11i0.4135Nepal Journal of Science and Technology 11 (2010) 133-138

scholarly journals Dynamics of Abies spectabilis in Relation to Climate Change at the Treeline Ecotone in Langtang National Park

2012 ◽  
Vol 12 ◽  
pp. 220-229 ◽  
Author(s):  
Narayan P Gaire ◽  
Yub R Dhakal ◽  
Harish C Lekhak ◽  
Dinesh R Bhuju ◽  
Santosh K Shah
Keyword(s):  
National Park ◽  
Age Distribution ◽  
Silver Fir ◽  
Tree Line ◽  
Climatic Response ◽  
Treeline Ecotone ◽  
Central Nepal ◽  
Tree Ring Data ◽  
Abies Spectabilis ◽  
High Level

This paper is aimed to study the tree line dynamics of Himalayan silver fir (Abies spectabilis D. Don) based on its tree-ring data and age stand distribution at Langtang National Park, Central Nepal. Climatic response on radial growth, recruitment of A. spectabilis and its age distribution are carried out. The average tree density of the species in the study area (total 48 plots of 20 m x 20 m) was 236 no/ha while that for sapling and seedling in the study area was 255 and 350 no/ha, respectively. The stand character and age distribution of the species showed a high level of recruitment in the recent decades, with decreased in average age along with increased altitude. Tree-growth climate relationship showed negative response with temperature of March-May. Upward advancement of tree line is expected in the coming recent decades though not necessarily uniform through the line.DOI: http://dx.doi.org/10.3126/njst.v12i0.6506 Nepal Journal of Science and Technology 12 (2011) 220-229 

Soil clay content and fire frequency affect clustering in trees in South African savannas

2008 ◽  
Vol 24 (3) ◽  
pp. 269-279 ◽  
Author(s):  
Thomas A. Groen ◽  
Frank van Langevelde ◽  
Claudius A.D.M. van de Vijver ◽  
Navashni Govender ◽  
Herbert H.T. Prins
Keyword(s):  
South African ◽  
Tree Species ◽  
National Park ◽  
Clay Content ◽  
Abundant Species ◽  
Fire Frequency ◽  
Kruger National Park ◽  
Annual Rainfall ◽  
Soil Clay Content ◽  
The Impact

Abstract:In this paper, we investigate which factors determine tree clustering in Southern African savannas. This was tested by measuring clustering of trees using the T-squared sampling method in plots of the Kruger National Park experimental burning programme in South Africa. Fire return interval is the main treatment in these plots, but also several auxiliary determining parameters like clay content in the soil, diameter of tree canopies, understorey composition, tree species diversity and average annual rainfall were measured while sampling. In the Kruger National Park 48 plots distributed over four different landscape types and with three different burning treatments (never, once every 3 y and annually) were sampled. First, we related the clustering of trees to these environmental variables. When looking at the most abundant species in each plot, the analysis revealed that clustering is mainly correlated with clay content in the soil. This analysis also showed that fire frequency had a positive effect on the clustering of tree species that are not very abundant. We suggest that less abundant species might be less resistant to fire and therefore adopt a mechanism of clustering to exclude grass fires under their canopy. Finally, we tested the effect of clustering on the impact of fire on trees by analysing the relationship between the distance of a tree to its nearest neighbour and its canopy diameter. We found that clustering reduces the damaging effect of fire on trees. Our study contributes to understanding of savanna functioning by showing which processes are relevant in the distribution of savanna trees.

scholarly journals Dynamique des peuplements ligneux dans le Parc National de Manda, au sud du Tchad

2019 ◽  
Vol 42.1 ◽  
pp. 7139-7152
Author(s):  
Guiguindibaye MADJIMBE ◽  
Goy SARADOUM ◽  
Touroumgaye GOALBAYE ◽  
Esaïe WAYA ◽  
Jonathan POUNAKOUMNA
Keyword(s):  
National Park ◽  
Basal Area ◽  
Average Density ◽  
Anthropogenic Pressure ◽  
Average Volume ◽  
Specific Composition ◽  
Gradual Evolution ◽  
Standing Timber ◽  
Composition Spécifique ◽  
Structure Des Peuplements

1 RÉSUMÉ La présente étude a pour but d’étude la dynamique des peuplements ligneux dans le Parc National de Manda. Elle vise à déterminer les caractéristiques structurales, la composition spécifique et la régénération des peuplements ligneux. Quatre sites ont été implantés depuis 2012. Nous avons procédé à la caractérisation des peuplements ligneux par des relevés dendrométriques. La flore ligneuse dans l’ensemble des sites est riche de 87 espèces reparties en 56 genres et 22 familles. Les sites 1 et 2 ont des effectifs plus élevés en 2019 comparativement en 2014 et en 2012. Une forte régénération s’est effectuée durant l’année 2019. Contrairement aux sites, 1 et 2, les sites 3 et 4 présentent pour l’année 2019 une forte baisse des effectifs de jeunes plants. Ces jeunes plants sont très sensibles non seulement à la disponibilité des ressources en eau pour franchir la saison sèche mais aussi à l’intensité et à la fréquence de passage des feux. Les résultats ont permis de noter que la densité moyenne entre 2012 et 2014 s’est accrue et à partir de 2014 elle s’est stabilisée. La surface terrière par hectare est, en moyenne de 10,12 m2/ha pour 2012 ; 11,16 m2/ha pour l’année 2014 et de 11, 65 m2/ha pour l’année 2019. Pour l’ensemble des sites expérimentaux, on évalue le volume moyen de bois sur pieds à 12,31 m3/ha en 2012, à 12,46 m3/ha en 2014 et 12,08 m3/ha en 2019. Ces valeurs indiquent que les variations de volume moyen de bois sur pieds sont très faibles pour les sites pris dans leur ensemble. Les résultats obtenus, montrent aussi que 8 espèces se situent dans un processus d’évolution régressive et 4 autres dans un processus d’évolution progressive. La structure des peuplements ligneux n’a pas beaucoup évolué en 8 ans mais, elle apparaît fortement tributaire de la topographie et de la pression anthropique. ABSTRACT Dynamic of the woody populations in the National Park of Manda, to the south of Chad The purpose of this study is to study the dynamics of woody stands in the Manda National Park. It aims to determine the structure, specific composition and regeneration of woody stands. Four sites have been established since 2012. We have characterized the woody stands by dendrometric surveys. The woody flora in all sites is rich in 87 species divided into 56 genera and 22 families. Sites 1 and 2 have higher numbers in 2019 compared to 2014 and 2012. Strong regeneration took place in 2019. Unlike sites 1 and 2, sites 3 and 4 present for the year 2019 a sharp decline in the number of young plants; these seedlings are very sensitive not only to the availability of water resources to cross the dry season but also to the intensity and frequency of fire. The results showed that the average density between 2012 and 2014 increased and from 2014 it stabilized. The basal area per hectare is, on average, 10.12 m2 / ha for 2012; 11.16 m2 / ha for the year 2014 and 11, 65 m2 / ha for the year 2019. For all the experimental sites, the average volume of standing timber is estimated at 12.31 m3/ ha in 2012, 12.46 m3 / ha in 2014 and 12.08 m3 / ha in 2019. These values indicate that variations in average volume of standing timber are very low for sites taken as a whole. The results obtained also show that 8 species are in a process of regressive evolution and 10 in a process of gradual evolution. The structure of woody stands has not changed much in 8 years, but it appears highly dependent on topography and anthropogenic pressure.

Tree Species Diversity in Community Managed and National Park Forests in the Mid-Hills of Central Nepal

2014 ◽  
Vol 33 (8) ◽  
pp. 796-813 ◽  
Author(s):  
Shiva Shankar Pandey ◽  
Tek Narayan Maraseni ◽  
Geoff Cockfield ◽  
Karin Gerhard
Keyword(s):  
Species Diversity ◽  
Tree Species ◽  
National Park ◽  
Tree Species Diversity ◽  
Central Nepal

scholarly journals Forest Tree Composition: A Comparative Study of Timber Species in Bayelsa State Nigeria

2020 ◽  
Vol 2 (2) ◽  
pp. 64-73
Author(s):  
Samuel Olatokunbo Ihinmikaiye ◽  
Bernard Edache Ochekwu ◽  
Josiah Muonam Ikuli ◽  
Doris Akinjagunla Atinuke ◽  
Abel Zikenal Keresinbofa
Keyword(s):  
Tree Species ◽  
Basal Area ◽  
Ground Level ◽  
Diversity Indices ◽  
Forest Tree ◽  
Timber Species ◽  
Anthropogenic Pressure ◽  
Sample Plot ◽  
Management Options ◽  
Timber Tree

Measuring tree species diversity is critical for forest management, particularly where timber species suffer undue anthropogenic pressure. This study was carried out in Bayelsa State, Nigeria. A sample plot was systematically chosen from randomly selected communities in each of the three senatorial districts Bayelsa West (BW), Bayelsa East (BE) and Bayelsa Central (BC) of the State. Each sample plots measured 25 m x 25 m and all timber tree species that were at least six feet above ground level within each sample plot were identified, counted and measured. Fifty individual timbers were encountered in the sample plot at Ogobiri community in BW, fifty-two at Kolo 1 community in BE and fifty-six at Gbarain community in BC belonged to 18, 16 and 14 different families respectively. Families with the largest number of species in the plots were Gentianaceae and Meliaceae, and the highest diversity indices were recorded from BE senatorial district. Generally, the basal area of the sample plots increases with an increase in diameter at breast height. The forested zones were on flat terrain characterized by seasonal flood inundation, and the similarities of timber species in the plots occurred as (BW-BC)> (BW-BE)> (BC-BE). Also, four tree species Coelocaryon preussii, Sacoglottis gabonensis, Milicia excelsa and Triplochiton scleroxylon were identified as rare species, and management options that would ensure ad infinitum supply of timber species were proposed.

scholarly journals PHYLOGEOGRAPHIC STRUCTURE OF THE COMMERCIALLY IMPOR- TANT TROPICAL TREE SPECIES, DRYOBALANOPS AROMATICA GAERTN. F. (DIPTEROCARPACEAE) REVEALED BY MICROSATELLITE MARKERS

REINWARDTIA ◽  
2014 ◽  
Vol 14 (1) ◽  
pp. 43 ◽  
Author(s):  
Fifi Gus Dwiyanti ◽  
Koichi Kamiya ◽  
Ko Harada
Keyword(s):  
Genetic Diversity ◽  
Microsatellite Markers ◽  
Tree Species ◽  
National Park ◽  
Tropical Tree ◽  
Phylogeographic Structure ◽  
Timber Species ◽  
Malay Peninsula ◽  
Tropical Tree Species ◽  
The Impact

DWIYANTI, F.G., KAMIYA, K. & HARADA, K. 2014. Phylogeographic structure of the commercially important tropical tree species Dryobalanops aromatica Gaertn. F. (Dipterocarpaceae) revealed by microsatellite markers. Reinwardtia 14(1): 43 – 51. ? Dryobalanops aromatica Gaertn. F. (Kapur) is an economically important timber species in Southeast Asia that can serve as a good model for studying the impact of the Pleistocene glaciations on the genetic diversity and distribution of species in tropical regions. Seven polymorphic microsatellite markers were analyzed in five natural populations of D. aromatica (N = 120 individuals): Gunung Panti in Malay Peninsula, Lingga Island in Lingga Archipelago, Lambir Hills National Park, Limbang and Similajau National Park in Borneo. The level of gene diversity (HE) for the five populations was relatively high with a range from 0.571 (Similajau) to 0.729 (Gunung Panti). The high genetic diversity in the present study could be attributed to the larger refugia population sizes of D. aromatica than that of other species. The population genetic structure revealed two distinct groups: the Malay Peninsula-Lingga Archipelago and Borneo. This pattern suggests that populations in each geographical area might be the consequence of post-glacial expansion from one or two refugia, but that gene flow between different glacial refugia was fairly restricted.

Regeneration status of trees under different disturbances regimes at southern fringe of Corbett National Park of Uttarakhand Himalaya

2018 ◽  
Vol 41 (1) ◽  
pp. 83-94
Author(s):  
Vivek Pandey ◽  
Keyword(s):  
Tree Species ◽  
National Park ◽  
Grazing Pressure ◽  
Anthropogenic Pressure ◽  
Shorea Robusta ◽  
Regeneration Status ◽  
Disturbed Forest ◽  
Southern Fringe ◽  
Disturbed Site ◽  
Uttarakhand Himalaya

Increasing anthropogenic pressure and dependence on plant products has led to widespread exploitation of natural forest in Uttarakhand Himalaya. The study area was selected on the Southern Boundry of Corbett National Park. The objective of the present study was to understand the regeneration status of important tree species in three different types of forests categorized as Highly Disturbed, Moderately disturbed and Least Disturbed sites. Total tree density was higher for least disturbed forest and lower for highly disturbed forest. The regeneration was poor in highly disturbed site compared to least disturbed site. Mallotus philippinensis was germinating and growing as a dominant under canopy tree species across all the sites except least disturbed sites. Sal (Shorea robusta) regeneration was found to be a serious problem. Mallotus philippinensis, Aegle marmelos and Lagerstroemia parviflora showed their dominance across all the sites proving broad ecological amplitude and high tolerance against grazing pressure. At highly disturbed site, species like Mallotus philippinensis, Diospyros tomentosa and Lagerstromeia parviflora were regenerating fairly well with seedlings and saplings but the number of saplings were either less than or equal to adults. Vegetational parameters showed that protected areas ( least disturbed areas ) are important for maintaining regeneration and ecosystem.

Environmental Correlates of Tree Species Diversity in Stage III of Kakadu National Park, Northern Australia

1993 ◽  
Vol 41 (6) ◽  
pp. 649 ◽  
Author(s):  
DMJS Bowman ◽  
JCZ Woinarski ◽  
KA Menkhorst
Keyword(s):  
Tree Species ◽  
National Park ◽  
Basal Area ◽  
Clay Content ◽  
Stage Iii ◽  
Environmental Correlates ◽  
The Family ◽  
Components Analysis ◽  
Soil Clay Content ◽  
Genus Eucalyptus

A quadrat based survey that sampled across the environmental range of the geologically and topographically diverse Stage III of Kakadu National Park, Northern Territory, revealed that the region has a tree flora dominated by the family Myrtaceae, and the genus Eucalyptus in particular. Principal components analysis (PCA) defined three axes of environmental variation: site rockiness, site hydrology and surface soil clay content. The three PCA axes were divided into halves and a 2x2x2 matrix was created to classify eight environments; however, there were quadrats in only seven of the eight possible environments. Kruskal-Wallis one-way ANOVAs showed that there was significant variation of the following variables between the 7 environments: total basal area, tree species richness, proportion tree richness composed of eucalypt species, and proportion of eucalypt richness composed of the four subgenera Blakella, Corymbia, Eudesmia and Symphyomyrtus. Of the most abundant 25 tree species and other common eucalypts only five species (Allosyncarpia ternata, Eucalyptus bigalerita, E. clavigera, E. foelscheana and E. jacobsiana) did not have significant differences in their mean basal area between the seven environments. The above patterns are interpreted as evidence that the savanna is a highly evolved system rather than the product of geologically recent disturbance to a once widespread monsoon rainforest.

Frugivory and the fate of dispersed and non-dispersed seeds of six African tree species

1996 ◽  
Vol 12 (4) ◽  
pp. 491-504 ◽  
Author(s):  
Colin A. Chapman ◽  
Lauren J. Chapman
Keyword(s):  
Tree Species ◽  
National Park ◽  
Seedling Recruitment ◽  
Seedling Survival ◽  
Kibale National Park ◽  
Lower Probability ◽  
Foraging Activity ◽  
Seedling Density ◽  
Trade Off ◽  
The Relationship

ABSTRACTThe relationship between seedling recruitment (under and away from parent trees) and the behaviour of seed dispersers and predators, was explored in a three-year study in Kibale National Park, Uganda. On the basis of 1261 hours of observation, the foraging activity of the diurnal frugivores which fed on fruit from six tree species was quantified. The fate of dispersed and non-dispersed seeds and seedlings was examined experimentally. The findings suggest that a trade-off exists between factors that promote seedling growth in areas with high seedling density and factors that promote dispersal by frugivores. For example, dispersal ofMimusops bagshaweiincreases both seed and seedling survival; seeds placed away from adult conspecifics had a 8% lower probability of disappearing than seeds placed under adults and seedlings away from adults had a 30% greater probability of surviving than seedlings grown under adults. In contrast, forUvariopsis congensis, dispersed seeds had a 56% greater probability of disappearing than seeds directly under a parent tree, while the survival of dispersed and non-dispersed seedlings was similar. Non-dispersed seed and seedling disappearance were correlated with the percentage of the fruit crop removed from focal trees, suggesting that the ability to survive under an adult maybe related to other aspects of the tree's life history.

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