• Journal of Forest and Environmental Science
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• v.39 no.2
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• pp.65-72
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• 2023

The endangered species of Cyathea spinulosa (tree ferns) are among the least concerned ferns of Nepal that bring threats to them and their habitat. A way to reduce such threats is by maintaining a database of species' whereabouts and generating a scientific understanding the habitat preferences. This will eventually help in the formulation of conservation plans for the species. This research aimed to characterize the suitable habitat of C. spinulosa by enumerating the location of species in the Panchase Forests of central Nepal. The statistical index method was applied to relate the occurrence locations of species with various environmental factors for the development of indices. The suitable habitat of C. spinulosa (more and most suitable categories) covered 119 km² and accounted for 43% of the total area studied. 74.4% of occurrence locations of C. spinulosa were recorded from these habitats. The habitat characteristics suitable for C. spinulosa were: proximity to streams (high moisture), land covered by forested area (shady area), mid-elevations of hills about 1,000 m to 2,000 m (sub-tropical climate), slope gradient of 20° to 40° (steep slopes), and northern to eastern aspects. These habitat characteristics could be considered for in-situ protection of tree ferns and designating the conservation plots.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.2
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• pp.187-194
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• 2016

In this paper, as a basic research for the restoration and construction of easuary saltmarsh, To observe the habitat environment for reed, we observed sediment environment (Particle size, water content, pH, nutrient analysis ($NH_4-N$, $PO_4-P$)), ground water level, ground level, individual numbers of reed, maximum reed height. As a result of this study, sediment particle size and moisture content of soil on the study area not effected reed habitat, pH showed no difference in each site. $NH_4-N$ and $PO_4-P$ concentration also no difference in each site. Ground level of reed habitat area is more higher than none reed habitat. However Ground water level of reed habitat area is more lower than none reed habitat. As a results of analyzing the influence factors for reed habitat in Nakdong estuary saltmarsh, ground water level and ground level is most influenced factor for reed habitat.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.6
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• pp.894-905
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• 2010

A habitat evaluation method was used to estimate the optimum suitability of the study area for the target algae. Habitat evaluation was carried out using an habitat evaluation procedure (HEP) so that the optimum suitability was quantitatively estimated for carrying out marine afforestation in the study area. According to the results of the suitability analysis, the variation of light and wave conditions according to depth showed the factors with the largest impact to involve the spatial distribution of suitable locations within the area. The total suitable area selected was calculated to be 18ha. The quality of the target algae (Ecklonia cava Kjellman) habitat was analyzed using an habitat suitability index (HSI) model of the HEP, which showed 0.55-0.907 (the maximum value being 1.0). This indicated that artificial reefs for afforestation should be installed to zonation type because the suitable area selected (The HSI value was 0.55~0.907) was distributed within the same depth line.

• Ecology and Resilient Infrastructure
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• v.2 no.1
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• pp.33-41
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• 2015

In this study, an optimal improvement method of stream channel structure is presented for the enhancement of fish habitat suitability by genetic algorithm. The correlation between fish habitat suitability and physical disturbance in stream is analyzed according to the changes of hydraulic characteristics by channel structure rehabilitation. Zacco koreanus which is an indicator fish of the soundness of aquatic ecosystem was selected as a restoration target species by investigating the community characteristics of fish fauna and river environments in Wonju stream. The habitat suitability is investigated by PHABSIM with the habitat suitability index of Zacco koreanus. Hydraulic analysis by HEC-RAS and physical disturbance evaluation in stream are carried out. The optimal channel width modified for the enhancement of fish habitat suitability is provided. The correlation analysis between habitat suitability and physical disturbance with the change of hydraulic characteristics by channel modification showed that the proper channel modification enhanced fish habitat suitability and mitigated physical disturbance in the stream. The improvement of physical disturbance score by the channel structure rehabilitation for the enhancement of fish habitat suitability was confirmed in this study.

• Ocean and Polar Research
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• v.42 no.1
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• pp.21-31
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• 2020

Shorebirds migrating along the East Asian-Australasian Flyway (EAAF) have been drastically decreasing due to continuous area loss and quality degradation of intertidal mudflats in the Yellow Sea. Evaluating the current habitat quality by means of habitat carrying capacity estimation could be effective in predicting the magnitude of impacts caused by habitat loss and provide better understanding to improve management strategies. In this study, we estimated the total biomass of Macrophthalmus japonicus, a main prey item of curlews in the Korea peninsular as habitat carrying capacity of the southern intertidal mudflat of Ganghwa Island, one of the key stopover sites for curlews in the EAAF. The result of the estimation took into account spatial differences of prey biomass and the available foraging time by tide patterns. Accordingly, it was found that curlew populations account for 30.26% of the habitat carrying capacity. When we calculated the mean biomass of the area and extrapolated it to the whole area to calculate the total biomass, it was found that the curlews have consumed 10.92% of the total biomass. The results show that the habitat carrying capacity of the southern intertidal mudflat of Ganghwa Island has decreased by 7.8% compared to a study conducted twenty years ago employing the same method. This study shows that there can be considerable differences in the results of habitat carrying capacity estimation between different methods, indicating that various environmental factors that affect the estimation results of habitat carrying capacity must be considered to achieve a more precise analysis and assessment.

• The Journal of Fisheries Business Administration
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• v.51 no.4
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• pp.19-45
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• 2020

This study is to evaluate economic effect of the creation project of snow crab, Chionoecetes opilio, spawning and habitat ground in Uljin and Youngdeok county. The main results of this study are summarized as follows: first, 14,400 million won was invested in the creation project cost of Chionoecetes opilio spawning and habitat ground of Uljin and Youngdeok County from 2015 to 2020. Second, the creation project of Chionoecetes opilio spawning and habitat ground directly provides fishing benefits, festival benefits, research and development benefits and employment benefits. Third, on the basis of above benefits, the creation project of Chionoecetes opilio spawning and habitat ground has net present value of 29,900.53 million won, internal rate of return 16.9%, and benefit-cost of 2.91 under a 4.5% social discount rate. Also, the creation project creates 195 jobs. This indicates that the creation project of Chionoecetes opilio spawning and habitat ground not only contributes to the increase in the income of coastal fishery and fishing villages but also to the job making. The result of this study provides useful information to policy makers or project managers as it shows that the project to create spawning and habitat ground should be carried out in consideration of the resource and biological characteristics of individual fish and that economic assessment logic should also be developed based on this. Also, it proves that the project to create a snow crab spawning and habitat ground is a national and local infrastructure project that increases the actual fishing income in the region. At the same time, it maintains the reproducibility function of most fish species, along with enhancing the people's benefits such as fishing village tourism and marine product consumption. Moreover, it provides useful information on budgeting for the continuous development of snow crab spawning and habitat ground in the mid to long-term.

• Journal of Ecology and Environment
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• v.43 no.1
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• pp.73-83
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• 2019

Background: Habitat selectivity and ecology of freshwater fishes were studied in two selected streams and their junction point which consist a total of 39 microhabitats. The aims of this study were to describe the habitat preference and its availability to fish assemblage, as well as ecology, habitat use, and habitat characteristics. Methods: We collected fish with backpack electrofishing three times during August 2013, December 2013, and March 2014. Using a variation partitioning approach of R software, we studied the relationship of fish abundances with stream type, habitat type, and abundance of key macroinvertebrate taxa. Results: A total of 6554 fishes representing four species belonging to the family Cyprinidae were caught. A higher total fish abundance was recorded from Gereb Tsedo (4870; 74.3%) than from Elala stream (1684; 25.7%). Taking both streams together, the overall total relative fish abundance was significantly higher in pools (53%) than in runs (35%) and in riffles (12%) at P < 0.05. Species-wise comparisons showed that 71%, 15%, 13%, and 1% of the pool fish community were occupied by Garra blanfordii, Garra ignestii, Garra dembecha, and Garra aethiopica, respectively. Stream type, habitat type, and key macroinvertebrate taxa each explained a significant proportion of the variation in fish abundance. Based on the variation partitioning approach, fish abundance was higher in Gereb Tsedo stream (P < 0.01). Moreover, fish abundance increased with pool habitat type (P < 0.01) and with availability of key macroinvertebrate taxa (P < 0.01). Conclusion: Fish abundance differed between stream types, among habitats and among key macroinvertebrate taxa availability. Among the factors, habitat type was the most important driving factor behind variation among fish abundances, and pool supports the highest fish abundance.

• Journal of Wetlands Research
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• v.19 no.4
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• pp.433-442
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• 2017

As a result of the Four-River Restoration Project in Korea, the habitat of endangered plant species of Aster altaicus var. uchiyamae and Polygonatum stenophyllum, which had been natively grown in the riparian zone of Namhan River, was destroyed and artificial replacement habitats were created. In this study, Habitat Suitability Index (HSI) was used to determine whether the replacement habitats are suitable for each species or not. From October 2015 to July 2016, Habitat Evaluate Procedures (HEP) were conducted on two replacement habitats of A. altaicus var. uchiyamae (Gangcheonsum and Sum-River) and on two replacement habitats of P. stenophyllum (Gangcheonsum and Youngjuk) in the Namhan River watershed. As evaluation parameters for A. altaicus var. uchiyamae habitat, habitat matrix (ratio of unburied gravel), height above the ordinary water level, soil nutrients, and light conditions were selected and for P. stenophyllum habitat, soil texture, light conditions, and coverage of companion species were selected. HSI was applied to evaluate the suitability of each replacement habitat. According to the result of the evaluation, replacement habitats of A. altaicus var. uchiyamae and P. stenophyllum located in Gangcheonsum have relatively high HSI values as 0.839 and 0.846, respectively. On the other hand, replacement habitats of A. altaicus var. uchiyamae in Sum-River and P. stenophyllum in Youngjuk zone have HSI value of 0, indicating unsuitable habitats for these species. This is the first attempt to apply HSI for plant species in Korea and proved the usefulness of HSI on plants.

• Journal of Korean Society on Water Environment
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• v.37 no.3
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• pp.217-228
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• 2021

This paper discusses a methodology where an integrated modelling framework is used to quantify the risk derived from anthropic activities on habitats and species. To achieve this purpose, a tool comprising the Delft3D and HABITAT model, was applied in the Yeongsan river. Delft3D effectively simulated the operational condition and flow of weirs in river. In accuracy evaluation of the Delft3D-FLOW, the Bias, Pbias, Mean Absolute Error (MAE), Nash-Sutcliffe Efficiency (NSE), and Index of Agreement (IOA) were used, and the result was evaluated as grade above 'Satisfactory'. The HABITAT calculated Habitat Suitability Value (HSV) for the following eight species: mammal, fish, aquatic plant, and benthic macroinvertebrate. An Area was defined as a suitable habitat if the HSV was larger than 0.5. HABITAT was judged accurately by measuring the Correct Classification rate (CCR) and the area under the ROC curve (AUC). For benthic macroinvertebrate, the CCR and AUC were 77% and 0.834, respectively, at thresholds of 0.017 and 4 inds/m² for HSV and individuals per unit area. This meant that the HABITAT model accurately predicted the appearance of the benthic macroinvertebrates by approximately 77% and that the probability of false alarms was also very low. As a result of evaluating the suitability of habitats, in the Yeongsan river, if the annual "lowest level" (Seungchon weir: 2.5 EL.m/ Juksan weir: -1.35 EL.m) was maintained, the average habitat improvement effect of 6.5%P compared to the 'reference' scenario was predicted. Consequently, it was demonstrated that the integrated modelling framework for habitat suitability assessment is able to support the remedy aquatic ecological management.

• Journal of Ecology and Environment
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• v.46 no.4
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• pp.316-323
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• 2022

Background: We developed a habitat suitability index (HSI) model for Pedicularis hallaisanensis, a Grade II Endangered Species in South Korea. To determine the habitat variables, we conducted a literature review on P. hallaisanensis with a specific focus on the associated spatial factors, climate, topography, threats, and soil factors to derive five environmental factors that influence P. hallaisanensis habitats. The specific variables were defined based on the collected data and consultations with experts in the field, with the validity of each variable tested through field studies. Results: Mt. Seorak had a suitable habitat area of 2.48 km² for sites with a score of 1 (0.62% of total area) and 0.01 km² for sites with a score of 0.9. Mt. Bangtae had a suitable habitat area of 0.03 km² for sites with a score of 1 (0.02% of total area) and 0 km² for sites with a score of 0.9. Mt. Gaya showed 0.13 km² of suitable habitat for sites with a score of 1 (0.17% of total area) and 0 km² for sites with a score of 0.9. Lastly, Mt. Halla showed 3.12 km² of suitable habitat related to sites with a score of 1 (2.04% of total area) and 4.08 km² of sites with a score of 0.9 (2.66% of total area). Mt. Halla accounts for 73.1% of the total core habitat area. Considering the climatic, soil, and forest conditions together with standardized collection sites, our results indicate that Mt. Halla should be viewed as a core habitat of P. hallaisanensis. Conclusions: The findings in this study provide useful data for the identification of core habitat areas and potential alternative habitats to prevent the extinction of the endangered species, P. hallaisanensis. Furthermore, the developed HSI model allows for the prediction of suitable habitats based on the ecological niche of a given species to identify its unique distribution and causal factors.