• Korean Journal of Environment and Ecology
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• v.32 no.2
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• pp.185-202
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• 2018

Many ecological studies regarding forest succession, which is the process of arriving at climax forest through ecological changes, have suggested that Carpinus laxiflora is the leading tree type of the climax forest of temperate zone in South Korea. However, most of these studies on C. laxiflora forest have focused on vegetation structure and succession process in specific areas or regional physiognomical forest communities, and thus some may question whether it is rational to consider C. laxiflora forest as the climax forest in South Korea's temperate forest zone. The purpose of this study was to analyze the vegetation classification, species composition, and stratum structure and to investigate the succession tendency with the vegetation data collected from C. laxiflora forests in 75 quadrates in 17 mountains between 2014 and 2017. We used the phytosociological method to analyze the vegetation structure and the importance value to analyze the stratum structure. The results showed the floristic composition of 6 vegetation units and 9 species groups. The hierarchy of the C. laxiflora community group was represented by the Ulmus laciniata community, Corylus heterophylla community (subdivided Quercus aliena group and Corylus heterophylla typical group), and Rhododendron schlippenbachii community (subdivided Fraxinus chiisanensis group, Carpinus tschonoskii group, and Rhododendron schlippenbachii typical group). Successional tendency of C. laxiflora forest based on the importance of each layer is predicted to be the total of three types such as to maintain the stand (vegetation units 2, 3, and 6), to success the Carpinus cordata forest (vegetation units 1 and 4), and to success Quercus acuta forest (vegetation unit 5).

• Journal of Korea Water Resources Association
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• v.56 no.2
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• pp.139-150
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• 2023

Terretial LiDAR surveying is highly useful for maintenance of civil facilities as it can easily detect the temporal deformation of structures or topography. However, for river facilities such as levess, it is difficult to detect the deformation of the topography or structure under vegetations due to the influence of vegetation. Vegetation filters can be divided into color filters and morphological filters. In this study, combined filters with color and morphology are developed to improve the accuracy of vegetation filters. 8 color filters, 6 morphological filters, and 4 combined filters are applied to the vegetation removal on the embankment slope, and their accuracy and calculation time are compared. Color filters show a short calculation time, but the accuracy was low in the vegetation area. Morphological filters show high accuracy in the vegetation area, but low accuracy in places with severe local topographical changes such as heavy rocks. Combined filters also show a tendency similar to morphological filters, but in the case of ExGGM, the accuracy is excellent in both the vegetation and rock area. Considering the accuracy and calculation time, the combined filter ExGGM is suitable for general cases, and the shape filter GrMIn or the complex filter ExGISL is suitable for cases where the local topographical change is not severe.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.516-529
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• 2021

Coniferous forests in the Baekdudaegan protected area are gradually losing their landscape diversity and uniqueness along with their ecological stability due to changes in vegetation composition and structures caused by various disturbance factors, such as climate change, vegetation succession, and human interference. This study provides basic data for establishing a comprehensive conservation plan for coniferous forests in the Baekdudaegan protected area. We classified the vegetation unit types using the Zurich-Montpellier School of Phytosociology and two-way indicator species analysis methods and analyzed the species diversity and structural characteristics based on the vegetation information of 755 stands collected in the natural resources change survey of the Baekdudaegan mountains (2016 to 2020) by the Korea Forest Service. Therefore, the vegetation of the coniferous forests of theBaekdudaegan protected area was classified into 15 types under the vegetation unit hierarchy of two community groups, four communities, seven sub-communities, and 14 variants. Furthermore, we compared the total coverage among vegetation types, importance values, constancy classes, life-forms, and diversity indices. Additionally, the average total coverage and number of species per 100 m² of all coniferous forests were 232% and 21 species, respectively, with the species diversity and dominance indices averaging 1.907 and 0.222, respectively.

• Journal of Cadastre & Land InformatiX
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• v.50 no.2
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• pp.37-51
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• 2020

With the development of machine learning and deep learning technologies, there has been increasing interest and attempt to apply these technologies to the detection of urban changes. However, the traditional methods of detecting changes and constructing spatial information are still often performed manually by humans, which is costly and time-consuming. Besides, a large number of people are needed to efficiently detect changes in buildings in urban areas. Therefore, in this study, a methodology that can detect changes by classifying road, building, and vegetation objects that are highly utilized in the geospatial information field was proposed by applying deep learning technology to point clouds. As a result of the experiment, roads, buildings, and vegetation were classified with an accuracy of 92% or more, and attributes information of the objects could be automatically constructed through this. In addition, if time-series data is constructed, it is thought that changes can be detected and attributes of existing digital maps can be inspected through the proposed methodology.

• Ecology and Resilient Infrastructure
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• v.6 no.1
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• pp.34-48
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• 2019

Naeseong Stream is a natural sand-bed river that flows through mountainous and cultivated area in northern part of Gyeongbuk province. It had maintained its inherent landscape characterized by white sandbars before 2010s. However, since then changes occurred, which include construction of Yeongju Dam and the extensive vegetation development around 2015. In this study, long-term monitoring was carried out on Naeseong Stream to analyze these changes objectively. This paper aims to provide a dataset of the investigation on channel morphology and vegetation for the period 2012-2018. Methods of investigation include drone/terrestrial photography, LiDAR aerial survey and on-site fieldwork. The main findings are as follows. Vegetation development in the channel of Naeseong Stream began around 1987. Before 2013 it occurred along the downstream reach and since then in the entire reach. Some of the sites where riverbed is covered with vegetation during 2014~2015 were rejuvenated to bare bars due to the floods afterwards, but woody vegetation was established in many sites. Bed changes occurred due to deposition of sediment on the vegetated surfaces. Though Naeseong Stream has maintained its substantial sand-bed characteristics, there has been a slight tendency in bed material coarsening. Riverbed degradation at the thalweg was observed in the surveyed cross sections. Considering all the results together with the hydrological characteristics mentioned in the precedent paper (I), it is thought that the change in vegetation and landscape along Naeseong Stream was mainly due to decrease of flow. The effect of Yeongju Dam on the change of the riverbed degradation was briefly discussed as well.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.6
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• pp.95-113
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• 2018

We studied the change of wetland vegetation structure to understand ecological restoration process of wetlands through the field survey of ecological restoration projects in Incheon, Iksan and Busan. We compared the vegetation plan at the time of planted with the results of the vegetation monitoring in 2018, and analyzed the changes in wetland vegetation structure. Based on results, we attempted to understand the restoration process of those wetlands and discuss the management measures for sustainable wetland restoration. As a result, in the Incheon Yeonhee restoration wetland, the number of plant species was increased, from 18 species in 2016 to 29 in 2018. The dominant species, Myriophyllum verticillatum, covered the wetland most and its occupied area was increased. On the other hand, the distribution area of the planted emergent hydrophytes was reduced. The area of open water decreased from 71.7% in 2016 to 48.8% in 2018. In Busan Igidae restoration wetland, the number of plant species was increased, from 6 species in 2014 to 31 in 2018. The dominant species was Myriophyllum verticillatum and its occupied area was increased. The area of floating plant communities that planned has decreased. The open water area decreased from 83.9% in 2014 to 31.8% in 2018. In Iksan Sorasan restoration wetland, the number of plant species was increased, from 13 species in 2016 to 36 in 2018. The dominant species was Phragmites communis Trin. and its occupied area was increased. The other planted species showed a tendency to be decreased by Phragmites communis Trin. and its terrestrialization. The open water area decreased from 86.6% in 2016 to 6.7% in 2018. These results suggest that wetlands should be managed by considering the change of vegetation structure and open water areas based on the following succession process, because it affects the habitat suitability of wetland organisms and biodiversity as well. Thus, the continuous monitoring for the ecological structure of restored wetland is important, and it could be possible step to develop sustainable wetland ecological restoration model.

• Korean Journal of Remote Sensing
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• v.29 no.4
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• pp.351-360
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• 2013

Harmonic analysis enables to characterize patterns of variation in MODIS NDVI time series data and track changes in ground vegetation cover. In harmonic analysis, a periodic phenomenon of time series data is decomposed into the sum of a series of sinusoidal waves and an additive term. Each wave is defined by an amplitude and a phase angle and accounts for the portion of variance of complex curve. In this study, harmonic analysis was explored to tract ground vegetation variation through time for land-cover vegetation change detection. The process also enables to reconstruct observed time series data including various noise components. Harmonic model was tested with simulation data to validate its performance. Then, the suggested change detection method was applied to MODIS NDVI time series data over the study period (2006-2012) for a selected test area located in the northern plateau of Korean peninsula. The results show that the proposed approach is potentially an effective way to understand the pattern of NDVI variation and detect the change for long-term monitoring of land cover.

• Journal of Wetlands Research
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• v.11 no.1
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• pp.105-113
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• 2009

Heat energy exchange is very important processes in the coastal wetland ecosystems. We observed and analyzed the net radiation flux, the sensible heat flux, the latent heat flux and the soil heat flux, which are balanced in the heat energy balance, over a reclaimed land covered with reeds at Goheung, Jeonllanamdo where is horizontally plane. The atmospheric turbulence had been measured in order to estimate the heat transfer during 5 intensive observation periods (IOPs). It was considered that the soil consists of water, fine particles, and vegetation canopy that changes color and density according to the season. We examined the characteristics of the heat flux and the vegetation effect on the air temperature control. It was noted that the heat was transported mainly by latent heat flux in the summer season and the vegetation canopy decreased the daily temperature range due to the heat storage. The air temperature was lower at the IOPs site than near urban area. This showed that the coastal wetland covered with the vegetation control the thermal environment.

• Journal of Wetlands Research
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• v.25 no.4
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• pp.315-325
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• 2023

This study analyzed the disturbance process of river wetlands based on modern and contemporary maps and aerial photographs, and analyzed land cover and NDVI changes in the hydro-ecological impact zone around the Wangjin District. A stable sandbar was formed near Wangjinnaru and was naturally connected to the agricultural land within inland, but after the sandbar and river wetland were destroyed due to heavy floods, embankment construction, land readjustment, and comprehensive river management, artificial replaced wetlands and ecological parks were created, and sandbars in the form of river island were restored again. The change in land cover in the hydro-ecological impact zone showed that rice paddies and fields in agricultural areas decreased from 36.3% in 2013 to 22.9% in 2022, with the largest change in area to 814,476m². It was confirmed that the land cover was undergoing vegetation over time. Since the vegetation condition is good, a healthy food chain is formed in the waterfront ecosystem, which can be expected to be biodiversity-positive. Summarizing seasonal changes in the vegetation index, the overall change in the vegetation index was the largest in spring (March), followed by summer (June), and the change in autumn (September) was the smallest except for water. By land use, the overall vegetation index (NDVI) increased, including 39.1% improvement in alternative wetlands, 38.2% improvement in load, 44.3% improvement in ecological parks, 35.6% improvement in agricultural areas, and -8.1% decrease in water.

• Korean Journal of Environmental Biology
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• v.36 no.1
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• pp.50-61
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• 2018

The current study aimed to review the research trends on forest liming by age, country, and research topics, and seeks to summarize the effects of forest liming on soil, vegetation and water system in forest ecosystems. The recent goals of forest liming have been changed in response to changes in the acid deposition, and related studies have been mainly carried out in Europe and North America, where there is noted a massive forest decline, which was subsequently caused by acid rain. Most forest liming studies are noted to have focused on soil responses, however, the number of studies on the responses of vegetation and water system according to a literature review on the subject were relatively small. Meanwhile, forest liming influenced whole forest ecosystems through interaction between the soil, vegetation and water system as associated with the relevant regions. The changes in soil pH, base saturation, and cation exchange capacity by forest liming were noted as different depending on the soil layer and elapsed time after liming. The responses of vegetation to forest liming were shown in above- and below-ground plant growth and plant nutrient concentration, and also were noted to have varied depending on the available regional plant species and noted specific soil conditions. The chemical properties of the water system were changed similarly to those in the soil, leading to notable changes as seen in the planktons and available fish species in the region. Finally, these results could be used to plan further studies on forest liming, which would significantly benefit regional studies to promote the preservation of the species noted for protection in the region.