• Journal of Forest and Environmental Science
• /
• v.32 no.2
• /
• pp.129-139
• /
• 2016

Study was conducted to investigate tree diversity and its population and regeneration status in homegardens of upper Assam, Northeast India through field study by quadrat method. A total of 154 tree species have been recorded from 135 studied homegardens under 109 genera 53 families. Most of these species (79%) are indigenous to our country, while the rest (21%) arealiens (naturalized and cultivated exotics) by origin. Tree species richness per homegarden varies greatly in different homegardens and is ranged from 5 to 52 tree species with a mean of 22 ($SE{\pm}0.58$). A. malaccensis is the most dominant tree species in the studied homegardens contributed 34% of the total tree density of the documented trees. The tree density is much higher with 4,259 individuals $ha^{-1}$ but, basal area ($36.32m^2ha^{-1}$) is very less. Based on the number of individuals present, very rare species is accounted for 10%, rare species 39%, common species 19%, dominants 14% and predominant species 18% in the present study. The population density of 154 tree species is 4,259 (individuals $ha^{-1}$) for adults (>3.18 cm DBH), 5,902 (individuals $ha^{-1}$) for saplings and 38,164 (individuals $ha^{-1}$) for seedlings. The density of seedlings>saplings>adults represents good regeneration status of tree species in studied homegardens. The population structure study showed that about 8% tree species have good regeneration status, 9% have fair regeneration status, 48% have poor regeneration status and 34% tree species have no regeneration. Study suggests that research and development action is needed to stimulate regeneration of those tree species which having high importance value indices but showing poor or no regeneration. Based on present observation, it can be conclude that homegarden can emerge as an effective means for both economic well-being and biodiversity conservation in upper Assam, Northeast India.

• Journal of Forest and Environmental Science
• /
• v.32 no.3
• /
• pp.237-252
• /
• 2016

Improved knowledge of the environmental factors affecting the natural regeneration of tree species in limestone forest is urgently required for species conservation. We examined the environmental factors and tree species characteristics that are important for colonization in diverse forest stands growing on a limestone hill in northern Thailand. Our analysis estimated the relative influence of forest structure and environmental factors on the regeneration traits of tree species. We established sixty-four $100-m^2$ plots in four forest stands on the limestone hill. We determined the species composition of canopy trees, regenerating seedlings, and saplings in relation to the physical environment. The relationships between environmental variables and tree species abundance were assessed by canonical correspondence analysis (CCA), and we used generalized linear mixed models to examine data on seedling/sapling abundances. The CCA ordination indicated that the abundance of tree species within the mixed deciduous forest was closely related to soil depth. The abundances of tree species growing within the sink-hole and hill-slope stands were positively related to the extent of rocky outcropping; light and soil moisture positively influenced the abundance of tree species in the hill-cliff stand. Physical factors had a greater effect on tree regeneration than did factors related to forest structure. Tree species, such as Ficus macleilandii, Dracaena cochinchinensis, and Phyllanthus mirabilis within the hill-cliff or sink-hole stand, colonized well on large rocky outcroppings that were well illuminated and had soft soils. These species regenerated well under conditions prevailing on the limestone hill. The colonization of several species in other stands was negatively influenced by environmental conditions at these sites. We found that natural regeneration of tree species on the limestone hill was difficult because of the prevailing combination of physical and biological factors. The influence of these factors was species dependent, and the magnitude of effects varied across forest stands.

• The Korean Journal of Ecology
• /
• v.22 no.2
• /
• pp.65-68
• /
• 1999

In December-January of 1996-1997 and 1997-1998, information was gathered about vertical distribution of foraging sites of tits in 34 flocks in coniferous and deciduous forests. There was a significant effect of forest type on the distribution of foraging sites of each species. Habitat was classified into 5 height layers vertically: ground, bushes (usually＜1.5 m, up to 3 m), tree layer 1 (up to 1/3 of tree height), tree layer 2 (1/3-2/3 tree height). and tree layer 3 (＞2/3 tree height). There were differences among species: great tit (Parus major) foraged mostly on the ground, coal tit (P. ater) and long-tailed tit (Acrocephalus caudatus) - on the highest tree layer, marsh tit (P. palustris) was often seen on bushes, and varied tit (P. varius) - in tree layer 2. Smaller species used upper and outer parts of trees. suggesting that, like in most other similar studies. larger dominant species prevented smaller species from using inner parts of trees.

• Journal of Korean Elementary Science Education
• /
• v.26 no.3
• /
• pp.329-340
• /
• 2007

This study is to find out how well elementary school gardens work as places of observation learning. We compared the tree species planted in elementary school gardens with those which appeared in the science textbooks of the 7th Korean National Curriculum. The number of tree species are 60 throughout all the grades, specifically; 43 in the third grade, 22 in the fifth grade, 16 in the first grade, 15 in the second grade, 8 in the sixth grade, and 5 in the fourth grade, respectively. Their frequency of appearance (hereafter referred to as 'appearance frequency') throughout all the grades is 175, and the maximum frequency is 62 in the third grade. Of particular note is the fact that the appearance frequency in one grade was very high, meaning that a repeat study will not be conducted. The total number of tree species counted in the study was 13,028 and consisted of 167 species in 52 families. Only 23% of the total planted tree species, that is, 38 tree species appeared in the textbooks, so the ratio of the practical usage of school gardens was revealed to be low. In the school gardens, there are only an average of about 16 tree species per school. The fewest number of species in one school was 9 and the most was 22. The native species were 74 and the non-native species were 93. This means that almost all the planted species do not relate to observation learning in the textbooks. The 22 tree species among 60 species in the textbooks were not planted in the gardens. In conclusion, the degree of utilization of almost all the elementary school gardens examined during this investigation was very low.

• Journal of Forest and Environmental Science
• /
• v.31 no.3
• /
• pp.192-201
• /
• 2015

Information on plant diversity and community structure are required to chalk out necessary actions for conservation management. The present study assessed the composition and diversity of tree species in Kamalachari Natural Forest of Chittagong South Forest Division, Bangladesh, during April 2010 to November 2011. A total of 107 tree species belonging to 72 genera and 37 families were recorded, where Moraceae family was represented by maximum (11) species. Density, Basal area and volume of tree species were $418{\pm}20.09stem/ha$, $21.10{\pm}2.62m^2/ha$ and $417.4{\pm}79.8m^3/ha$ respectively. Diameter and height class distribution of tree species revealed an almost reverse J-shaped curve. Both the number of species and percentage of tree individuals were maximum in the lower DBH and height ranges. Anthropogenic disturbances like illegal tree cutting, over extraction, settlement inside forest area etc. were noticed during the study, which are supposed to cause gradual decrease of both tree species and individuals in the higher DBH and height classes. However, Artocarpus chama was found dominant showing maximum IVI followed by Schima wallichii, Aporosa wallichii, and Lithocarpus acuminata. The quantitative structure of the tree species of Kamalachari natural forest is comparable to other tree species rich tropical natural forests. The findings of the study may help in monitoring future plant population changes of the identified species and adopting species specific conservation programs in Kamalachari natural forest.

• Asian Journal of Turfgrass Science
• /
• v.16 no.2
• /
• pp.85-96
• /
• 2002

This study showed the current plantation of woody landscape plants of 42 school gardens in Daejeon metropolitan city. The ratio between evergreen tree and deciduous tree was 67% to 33%. The ratio between evergreen shrub and deciduous shrub was 48% to 52%. Also, 161 kinds of woody species were found; evergreen tree was 21 species, deciduous tree was 67 species, evergreen shrub was 16 species, deciduous shrub was 44 species, and vine and the others were 13 species. The proportion of native woody species was 61% (98 out of 161 species). 110 species were planted at the front garden area. In the mid-garden, 77 kinds of woody species were found. In the side garden, 95 kinds of woody species were found. In the rear garden, 92 kinds of woody species were found. The surrounding of play ground and outer area were planted 82 species. The first ranked evergreen tree was Juniperus chinensis‘Kaizuka’. And Deciduous tree, evergreen shrub, deciduous shrub, and vine showed Gingko biloba, Buxus microphylla var. koreana, Hibiscus syriacus, Wisteria floribunda, respectively. The school symbol of tree and flower was planted in 41 schools. The first rank plants of school symbol tree and flower were Pinus densiflora, Forsythia koreana and Rosa spp. Plant nameplate was found at 22 schools. The plant nameplate was used for 1∼10 species at 17 schools. In conclusion, plantation of landscape trees should be considered characteristic of each school area. In addition, school landscape should be planned distinction of a elementary school, a middle school, a high school, and a school for handicapped. School landscape should be considered carefully from functional, natural, educational environment and maintenance viewpoints as well as urban forest networking.

• Journal of Forest and Environmental Science
• /
• v.40 no.3
• /
• pp.227-240
• /
• 2024

Trees improve air quality through the accumulation of air pollutants in their leaves; however, the responses of different tree species to air pollution varies. Hence, this study evaluated the responses to air pollution of selected tree species in the Swamp Forest Research Station, Onne. Ten tree species (Cola pachycarpa, Khaya grandifoliolia, Irvingia gabonensis, Garcinia kola, Chrysophyllum albidum, Treculia africana, Dacryodes edulis, Tectonia grandis, Gmelina aborea, and Nauclea diderrichii) were selected based on their abundance in the area. Leaves were collected from all sides in 3 replicates for each tree species. Laboratory analysis was carried out using standard procedures. Portable Multi Gas Detector was used to determine the concentrations of air pollutants. One-way analysis of variance was employed to test for significant difference (p≤0.05) in biochemical parameters among the tree species while Pearson's correlation was utilized to determine the level of association between different biochemical parameters and APTI; heavy metals and APTI. Results showed high concentration of PM₁₀, CO, moderate concentration of NO₂, PM_2.5, and VOC, and low concentration of ground O₃. Heavy metals - Cadmium, Mercury, Lead, Nickel and Copper were all present in the tree species at varying rates. There were significant differences in the biochemical parameters and APTI values. C. pachycarpa exhibited the highest APTI value (89.88), while D. edulis had the lowest APTI value (8.24). C. pachycarpa, K. grandifoliolia, C. albidum, G. kola, T. africana, and N. diderrichii were identified as tolerant tree species to air pollution. G. aborea, T. grandis, and I. gabonensis were considered intermediate tolerant species, while D. edulis was the only tree species sensitive to air pollution. Ascorbic Acid, Chlorophyll, Hg and Ni had positive correlations with APTI; Cd and Cu had negative association with APTI at the 0.05 significance level. C. pachycarpa, T. africana, K. grandifoliolia, C. albidum, N. diderrichii and G. kola, are recommended for planting in pollution-prone areas.

• Journal of Forest and Environmental Science
• /
• v.30 no.4
• /
• pp.342-350
• /
• 2014

Rural people of Sudan are endowed with a deep knowledge concerning the utilization of different tree species. However research on the local knowledge related to tree species utilization still lacks adequate attention. The study objectives were to identify the existing local knowledge related to the utilization of the tree species and the existing threats to the availability of the trees. A total of 300 respondents were selected randomly from Rashad district in Nuba Mountains in 2011. Semi-structured interview, direct observation, group discussion, preference ranking and direct matrix ranking were used to collect the data. The study results revealed that people of Nuba Mountains utilize different tree species for food, medicinal purposes, fodder, firewood, construction and cultural ceremonies. The study results also indicated that the availability of trees is negatively influenced by firewood collection, agricultural expansion, drought, overgrazing and charcoal production. The study concluded that local knowledge has crucial role in tree species utilization in Nuba Mountains. Further researches to document and substantiate the local knowledge on useful tree species are highly recommended.

• Journal of Forest and Environmental Science
• /
• v.31 no.3
• /
• pp.177-191
• /
• 2015

The effect of environmental variables on the presence and abundance of tree species in a tropical lowland undisturbed limestone and non-limestone forest in Ben En National Park, Vietnam was investigated. The relationships between 13 environmental variables and 29 tree species with a DBH ${\geq}10cm$, as well as between six 6 physical variables with 26 species of seedling and sapling communities were assessed by canonical correspondence analysis (CCA). Data concerning all tree species ${\geq}10cm$ DBH were collected from eighteen $400m^2$ sample plots, while the abundance of regeneration (all individuals ${\leq}5cm$ DBH) was counted in fifty $2{\times}20m$ strip-plots. The significance of species-environments correlations were tested by distribution-free Monte Carlo tests. The CCA of the 29 examined tree species and 13 environmental variables indicated that the presence and abundance of the tree species were closely related to topographic factors. We may confirm that soil properties including pH, soil moisture content, and soil textures, were the most crucial factor in tree species composition and their distribution. Several species including Pometia pinnata, Amesiodendron chinense, Gironniera cuspidate, Cinnamomum mairei, and Caryodaphnopsis tonkinensis were not controlled by soil properties and topographic variables. The CCA also indicated that the abundance of regeneration tree species at all sites had positive and significant correlations with soil depth, while the occurrence of several other tree species (such as Koilodepas longifolium and Aglaia dasyclada) was positively correlated with a higher slope and rocky outcrop.

• Journal of Ecology and Environment
• /
• v.35 no.2
• /
• pp.91-98
• /
• 2012

This study was performed in order to suggest the possibility of tree species classification using high-resolution QuickBird-2 images spectral characteristics comparison(digital numbers [DNs]) of tree species, tree species classification, and accuracy verification. In October 2010, the tree species of three conifers and eight broad-leaved trees were examined in the areas studied. The spectral characteristics of each species were observed, and the study area was classified by image classification. The results were as follows: Panchromatic and multi-spectral band 4 was found to be useful for tree species classification. DNs values of conifers were lower than broad-leaved trees. Vegetation indices such as normalized difference vegetation index (NDVI), soil brightness index (SBI), green vegetation index (GVI) and Biband showed similar patterns to band 4 and panchromatic (PAN); Tukey's multiple comparison test was significant among tree species. However, tree species within the same genus, such as $Pinus$ $densiflora-P.$ $rigida$ and $Quercus$ $mongolica-Q.$ $serrata$, showed similar DNs patterns and, therefore, supervised classification results were difficult to distinguish within the same genus; Random selection of validation pixels showed an overall classification accuracy of 74.1% and Kappa coefficient was 70.6%. The classification accuracy of $Pterocarya$ $stenoptera$, 89.5%, was found to be the highest. The classification accuracy of broad-leaved trees was lower than expected, ranging from 47.9% to 88.9%. $P.$ $densiflora-P.$ $rigida$ and $Q.$ $mongolica-Q.$ $serrata$ were classified as the same species because they did not show significant differences in terms of spectral patterns.