• Plant Resources
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• v.4 no.3
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• pp.130-139
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• 2001

Four major naturally populated areas around the Jindong valley in Inje-Gun, Gangwon province for wild Pyrus ussuriensis, Malus sieboldii, and Malus baccata are mostly located on the southeast side of the mountains at 630-745m in altitude at sea level and are in very good sunny areas. The total of 77 taxa dividing into 32 families, 58 genera, 65 species, and 12 varieties has been inhabited in these areas. Most of these plants are heliophytes, which love sunshine, but some of rhizo-plants such as Sasa borealis, climbing plants such as Actinidia arguta and Celastrus orbiculatus, or naturalized plants like Bidens frondosa are also shown. These areas have been continually destroyed, so it is possibly thought that the second transition has been progressed. The index of species diversity of plant groups in these areas is 0.672∼1.465 based on the Shannon-Wiener's method, but its index for the area that rhizo-plants like Sasa borealis are growing as an under planting decreases relatively. In this study, the oldest plant of Pyrus ussuriensis in Korea, which is 120cm in diameter at breast height (DBH), 19m in tree height and 25m in width, has been found.

• Journal of Forest and Environmental Science
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• v.34 no.1
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• pp.31-45
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• 2018

At present the biodiversity of the riparian forest is under threat due to various anthropogenic pressures. Hence study was conducted along the three unprotected zones of riparian forest in Dikhu river, Nagaland, north-east India in order to compared the diversity, distribution and population structure of riparian trees. In each zone $100{\times}100m^2$ plot were marked and subdivided into 20 plots of $10{\times}10m^2$. 10 plots on each side of the river were taken randomly covering 0.02 ha. Only tree with dbh ${\geq}10cm$ and dbh above 1.5 m above ground level were recorded as individual species. A total of 29 tree species belonging to 18 families were recorded from the three zones of the river. Tree species richness was highest at the middle zone (19) followed by upper (14) and lower zone (7). The most abundant species and family recorded at upper, middle and lower zones were Melia azaderach of Euphorbiaceae ($380\;stems\;ha^{-1}$), Terminalia chebula of Euphorbiaceae ($432.5\;stems\;ha^{-1}$) and Duabanga grandiflora of Lythraceae ($365\;stems\;ha^{-1}$) respectively. The ranges of diversity indices observed in the three zones were: Shannon-Wiener index (1.25-0.73), Simpson diversity index (0.42-0.93), Evenness index (0.47-0.37) and Index of co-dominance (0.75-0.94). Rest of other indices were also estimated and compared. Distribution of trees shows the contagious pattern common in the upper and middle zones and regular in the lower zone. The girth size class analysis demonstrated that the riparian forest is in less mature succession stage. This study emphasize the need for management and conservation of riparian forest by developing policy to declare the riparian zone as protected area to prevent further degradation and loss of biodiversity from these unregulated zones along the river.

• Journal of Korean Society of Forest Science
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• v.103 no.3
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• pp.313-320
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• 2014

The purpose of this study was to provide basic data for preserving forest ecosystem with understanding forest wetland condition of Mt. Cheongok. It was found from this research that vascular plants of surveyed area were composed of 72 families, 167 genera, 209 species, and 2 subspecies, 27 varieties, 5 formae. totaling 243 taxa. Among the investigated vascular plants, Korea endemic plants were 9 species, rare plants 15 species, and naturalized plants 8 species, respectively. According to the occurrence frequency within the wetland investigated, obligate upland plants (OBU) accounted for 75.72% (184) among the total species investigated, wherea obligate wetland plant (OBW) were four species (4.65%). There were 26 of hygrophyte plants and 2 of emergent plants in the research area according to wet degree. According to habitat category, the most frequently occurred habitat was forest (136 species, 55.97%), and the others were in the order of meadow and shrubland (70 species, 28.81%), wet meadow (35 species, 14.40%), and aquatic environment (2 species, 0.82%), respectively. In the result of analysis of important value, Fraxinus rhynchophylla and Carex pseudosinensis was the highest as 22.17% and 10.40%. It was confirmed that the species diversity was relatively high. Shannon-Wiener's species diversity index was calculated as 2.507. Based on these results, long-term monitoring survey should be urgently needed for ecological restoration and recovery.

• Journal of Forest and Environmental Science
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• v.26 no.2
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• pp.117-129
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• 2010

The present study was undertaken in moist temperate forest of Mandal-Chopta area in the Garhwal region of Uttarakhand, India. The aim of the present study was to assess the physical properties of soils in relation to the forest structure and composition. Twelve forest types according to the altitude, slope aspect and species compositions were selected for the study. Physical properties of soil i.e., soil colour, soil texture (per cent of sand, silt and clay), moisture content, water holding capacity, porosity, bulk density (gm/$cm^3$) and void ratio were analyzed for three different depths viz., (i) 'upper' (0-10 cm), (ii) 'middle' (11-30 cm) and (iii) 'lower' (31-60 cm) in all the selected forest types. Phytosociological and diversity parameters viz. total basal cover ($Gha^{-1}$), stem density ($Nha^{-1}$), tree species richness, Simpson concentration of dominance and Shannon-Wiener diversity index were also calculated for each forest type. This study also provides the comparisons between the results of physical analysis of the present study with numerous other previous studies in the temperate Himalayan region of the Uttarakhand.

• Journal of Environmental Science International
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• v.12 no.1
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• pp.15-22
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• 2003

Fifteen major naturally populated habitats around the Mt. Halla, Jeju province for wild Cornus kousa are mostly located on the southeast side of the mountains at 850-1,550m in altitude at sea level and are in half sunney areas. More than 40.0% of the naturally populated area of Cornus kousa are edge of forest areas and 53.3% populate on the steep slope of the mountain in 0-5℃. The direction of the slop for about 40.0% of total populated areas is southeast. In the naturally populated areas, total of 64 taxa dividing into 42 families, 59 genera 56 species and 8 varieties have been shown, mostly Hydrangea petiolaris, Rubus oldhamii, Ilex crenata, Sasa quelpaertensis, Ligustrum obtusifolium. It is suggested that these areas are secondary forest in a typical deciduous forest in Mt. Halla where the second transition had been progressed after forest damage or environmental stress. The index of species diversity of plant groups in these areas is 1.286-4.238 based on the Shannon-Wiener's method.

• Korean Journal of Ecology and Environment
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• v.54 no.2
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• pp.108-119
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• 2021

We aimed to develop a naturalness index for forest-dwelling birds in four national parks in Korea and to simulate the effect of species loss on this naturalness index. Five bird specialists were asked to give 112 bird species a disturbance susceptibility score (DSS), and the naturalness index was calculated based on this. The 112 bird species represented 8 orders (Cuculiformes, Piciformes, Accipitriformes, Falconiformes, Columbiformes, Caprimulgiformes, Strigiformes, and Passeriformes). DSS was the highest for Terpsiphone atrocaudata and Pitta nympha, and lowest for Pica pica, Hypsipetes amaurotis, and Streptopelia orientalis. There was a significant negative relationship between a species' population number and its DSS. Among the four national parks, Mt. Songni had the highest naturalness index, followed by Mt. Wolak, Mt. Juwang, and Mt. Wolchul. We investigated the change in biodiversity indices under four scenarios, which assumed the extinction of species with less than 5 (Scenario 1), 10 (Scenario 2), 50 (Scenario 3), and 100 individuals (Scenario 4). The results showed that although all biodiversity indices decreased as the species loss increased, they all behaved differently. Fisher's alpha diversity decreased as the number of species proportionally decreased. There was almost no change in Shannon-Wiener H' index in Scenarios 1 and 2. The naturalness index showed increased sensitivity in Scenarios 1 and 4. Our future aims are to obtain the DSS for all forest-dwelling bird species, and to adopt the naturalness index to evaluate temporal and spatial changes in biodiversity.

• Journal of Ecology and Environment
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• v.48 no.3
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• pp.233-246
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• 2024

Background: In this research work, epilithic communities of diatoms in macrophytes are listed and described to evaluate the ecological conditions of the surface waters of the Chipoco River, whose basin has been exploited for agricultural and mining purposes, degrading natural ecosystems. The diatoms studied are found in calcareous tufa deposits developed in swampy environments where little of their benthic microbiota has been studied, despite the regional relevance of these calcareous formations within the manganese mining district. To describe the diatoms and evaluate the ecological condition of the surface waters, the Chipoco River was divided into three sectors (North, Center, and South) collecting a total of 15 samples along 10 km. For the taxonomic identification of diatoms, scanning electron microscopy techniques, consultations with specialists and specialized literature were used. To evaluate the ecological conditions of the Chipoco River, the linear correlation coefficient was used, where the relationships between diatom species and environmental variables were evaluated. Likewise, species diversity was determined by applying the Shannon-Wiener index and Simpson's dominance value (D) was calculated to detect diversity impoverishment processes. Results: Ten genera of diatoms were identified in bryophytes of the species Plagiomnium cuspidatum that grow on the banks of said river. The linear correlation coefficient indicated that physicochemical characteristics such as total dissolved solids, temperature, and calcium, and hydrochemical characteristics of the water intervene in the distribution and abundance of four diatoms Rhoicosphenia abreviate, Epithemia turgida, Calloneis bacillum and Achanthidium minutissimum in the different sectors studied. The Shannon-Wiener diversity indices and Simpson's dominance show that there is greater diversity and marked dominance of diatoms in the northern sector compared to the central and southern sectors. Conclusions: Agricultural and mining activities and the poor sanitary infrastructure of human settlements have caused the Chipoco River to have poor ecological quality.

• Journal of Ecology and Environment
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• v.43 no.2
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• pp.183-190
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• 2019

Background: In the Philippines, the practice of planting mangroves over seagrass has been a practice done to promote coastline protection from damages done by storms. Despite the added protection to the coastline, the addition of an artificial ecosystem gradually inflicts damage to the ecosystem already established. In this study, seagrass communities that had no history of mangrove planting were compared with those that had mangrove planting. The percent substrate cover of seagrass in the sampling areas was determined, and the macroinvertebrates present in the sampling areas were also observed. The study was conducted based on reports of mangrove planting activity that disrupted seagrass functions on Santa Fe, Bantayan Island, Cebu. Transect-quadrat method sampling was done to assess the chosen sites. Results: Six species of seagrass was found on the site without mangrove planting which was barangay Ocoy (Cymodocea sp., Thalassia sp., Halodule sp., Enhalus sp., Halophila sp., and Syringodium sp.) and had a higher percent cover, while only four were found on the site with mangrove planting (barangay Marikaban). It was also found that barangay Marikaban had a lesser Shannon-Wiener and Simpson's index compared to barangay Ocoy. Jaccard's index of similarity between the two sites was low. Conclusion: With the results of the assessment, we recommend proper monitoring of future mangrove planting activities and that these activities should not disrupt another ecosystem as all ecosystems are important.

• Journal of Ecology and Environment
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• v.47 no.4
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• pp.250-260
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• 2023

Background: Crabgrass (Digitaria ciliaris, Poaceae) is a globally distributed weed, including in Afro-Eurasia, America, and Australia. As a highly gregarious plant, crabgrass is an important habitat for a diverse array of insects, and a potential habitat for agricultural pests. To compare the insect communities associated with the crabgrass community, insects were sampled using sweep sampling (100 sweeps per sample) at five sites, including Daejeon (Daejeon and Gap rivers), Anseong, Namhae, and Inje, with a focus on the Daejeon River. Results: A total of 5,888 individual insects belonging to eight orders, 42 families, and 115 species were collected from the five sites. Both the number of species and individuals of Hemiptera were the highest at all of the sites. In the present study, 73% of the insect population fed on D. ciliaris as a host plant. The dominant species in the D. ciliaris community was Laodelphax striatellus (Delphacidae), being ubiquitous at all the sites which showed a high abundance of rice pests in the communities and the suitability of D. ciliaris as an alternative host plant for them. The Shannon-Wiener diversity index was highest in Inje on 17 September (2.88), and the Chao1-bc diversity index was highest in the Gap River on 5 September (80). The sampling efficiency of 100 sweep samples (sample coverage) was calculated to be as high as 90%. The results of the samples taken from September to November in the Daejeon River showed that the number of species and individuals decreased gradually over time, and the number of dominant species decreased sharply between September and October. Similarity analysis indicated that sampling dates that were closer together yielded sampled assemblages with higher faunal similarity. In addition, in each sampling, the difference in the minimum temperature during the two-week period prior to sampling and faunal similarities were negatively correlated. Conclusions: This study provides foundational data that could enhance our understanding of insect diversity in D. ciliaris. The data can facilitate ecological conservation and management of Korean grasslands generally, as well as identification of potential pests that may disperse from D. ciliaris communities to nearby farmland.

• Korean Journal of Microbiology
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• v.46 no.3
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• pp.262-269
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• 2010

To investigate a quantitative evaluation of the actinobacteria, we have collected samples from various kinds of bamboo forest soil. Each different layers contained $2.7{\times}10^6-2.7{\times}10^8$ CFU/g of actinobacteria which was the highest in litter layers of Sasa boreali forest soil. We obtained 330 actinobacteria from different layers of bamboo forest soil; litter (100 strains), humus (70 strains), and rhizosphere soil (160 strains). Based on the colony morphology (aerial mycelium, substrate mycelium, and soluble pigment), isolates were divided into thirty-six groups and we selected 50 representative isolates. 16S rRNA gene sequence analysis showed Streptomyces was major actinobacteria (94%) and they were categorized as cluster I (2 strains), II (35 strains), III (6 strains), and IV (7 strains), respectively. The diversity index of 50 Streptomyces collected from the bamboo forest soil was calculated with the Shannon-Wiener method. Bamboo litter showed higher diversity index level of 3.33 than that of humus and rhizosphere soil. Also, antibiotic activities of our isolates were investigated against Botrytis cinerea, Xanthomonas campestris, Xanthomonas axonopodis pv. vesicatoria, and Bacillus cereus and found in 74, 16, 25, and 24 strains, respectively.