• Title/Summary/Keyword: Vegetation Loss

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On the use of alternative water use efficiency parameters in dryland ecosystems: a review

  • Kang, Wenping;Kang, Sinkyu
    • Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.246-253
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    • 2019
  • Background: Water use efficiency (WUE) is an indicator of the trade-off between carbon uptake and water loss to the atmosphere at the plant or ecosystem level. Understanding temporal dynamics and the response of WUE to climatic variability is an essential part of land degradation assessments in water-limited dryland regions. Alternative definitions of and/or alternative methodologies used to measure WUE, however, have hampered intercomparisons among previous studies of different biomes and regions. The present study aims to clarify semantic differences among WUE parameters applied in previous studies and summarize these parameters in terms of their definition and methodology. Additionally, the consistency of the responses of alternative WUE parameters to interannual changes in moisture levels in Northeast Asia dryland regions (NADRs) was tested. Results: The literature review identified more than five different WUE parameters defined at leaf and ecosystem levels and indicates that major conclusions regarding the WUE response to climatic variability were partly inconsistent depending on the parameters used. Our demonstration of WUE in NADR again confirmed regional inconsistencies and further showed that inconsistencies were more distinct in hyper- and semi-arid climates than in arid climates, which might reflect the different relative roles of physical and biological processes in the coupled carbon-water process. Conclusions: The responses of alternative WUE parameters to drying and wetting may be different in different regions, and regionally different response seems to be related to aridity, which determines vegetation coverage.

Assessment of Diversity of Forest Structure in Gunja-Dong, Siheung City, Korea (시흥시 군자동 일대 산림 구조의 다양성 평가)

  • Ryu, Ji-Eun;Kang, Jong-Hyun;Lee, Dong-Kun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.14 no.1
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    • pp.23-33
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    • 2011
  • Habitats loss and fragmentation are major threats to biodiversity. There are various kinds of environmental assessment have been developed for various problems to solve. Yet, there are no well-developed methods for quantifying and predicting about biodiversity. To achieve a sustainable conservation for biodiversity, the structural diversity of forest must be assessed by proper indexes. This study aim to quantitatively assess the diversity of forest structure as habitats and results of the verification by bird survey for objective presentation of evidence. As a result of literature review, some indexes were selected as potential prediction tools for biodiversity; area of patch, area of core regions, shape of patch and average age of stand. The assessment results were estimated by monitoring of birds for accuracy verification and the results were almost in agreement with each others. But, 1 and 2 level of forests were showed ambiguous results. Certainly, this study was limited in some valuation indexes on landscape scale. Further studies should be considered that different environmental factors such as land use, disturbances by human and vegetation index. Also, we expect that the additional monitoring of birds should give rise to the result which is improved assessment results.

Famine Relief during the Late Chosun dynasty in 『Limwomgyungjeji』 「Injeji」 (조선후기 『임원경제지(林園經濟志)』 「인제지(仁濟志)」 속의 구황(救荒))

  • Kim, Seung-Woo;Cha, Gyung-Hee
    • Journal of the Korean Society of Food Culture
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    • v.28 no.3
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    • pp.213-233
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    • 2013
  • During the late Chosun Dynasty, famine was the main cause of climate ecological background, such as frequent floods and droughts, the Little Ice Age (小氷期), and epidemic. In addition, it influenced the social and cultural background, such as failure toprovide Yiangbeop (移秧法), breakout of war and revolt, loss of farming cattle, grain consumption due to brewing, the concentration of wealth, and tenacity of shamanism. "Limwongyungjeji" "Injeji" of the last part had been written about the famine; wild plants to raw, dried, or dried powder, or processed pharmaceutical goods. Grain couldbe replaced in more than 330 types of famine relief food and recipes; 170 species of vegetables, 34 species of vegetation, and 33 kinds of fruit - the botanic foods were mainstream. Edible parts of these plant foods are those of 14 kinds: 175 species of leaves, 113 species of sprouts, 99 kinds of buds, and other fruits, roots, stems, flowers, etc. The recipe (poaching, salting, and oil-marinated) was written 186 times or forsoup, raw, and boiled.

Performance of Zoysia spp. and Axonopus compressus Turf on Turf-Paver Complex under Simulated Traffic

  • Chin, Siew-Wai;Ow, Lai-Fern
    • Weed & Turfgrass Science
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    • v.5 no.2
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    • pp.88-94
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    • 2016
  • Vehicular traffic on turf results in loss of green cover due to direct tearing of shoots and indirect long-term soil compaction. Protection of turfgrass crowns from wear could increase the ability of turf to recover from heavy traffic. Plastic turfpavers have been installed in trafficked areas to reduce soil compaction and to protect turfgrass crowns from wear. The objectives of this study were to evaluate traffic performance of turfgrasses (Zoysia matrella and Axonopus compressus) and soil mixture (high, medium and low sand mix) combinations on turf-paver complex. The traffic performance of turf and recovery was evaluated based on percent green cover determined by digital image analysis and spectral reflectance responses by NDVI-meter. Bulk density cores indicated significant increase in soil compaction from medium and low sand mixtures compared to high sand mixture. Higher reduction of percent green cover was observed from A. compressus (30-40%) than Z. matrella (10-20%) across soil mixtures. Both turf species displayed higher wear tolerance when established on higher sand (>50% sand) than low sand mixture. Positive turf recovery was also supported by complementary spectral responses. Establishment of Zoysia matrella turf on turfpaver complex using high sand mixture will result in improved wear tolerance.

Comparison of Three Land Cover Classification Algorithms -ISODATA, SMA, and SOM - for the Monitoring of North Korea with MODIS Multi-temporal Data

  • Kim, Do-Hyung;Jeong, Seung-Gyu;Park, Chong-Hwa
    • Korean Journal of Remote Sensing
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    • v.23 no.3
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    • pp.181-188
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    • 2007
  • The objective of this research was to investigate the optimal land cover classification algorithm for the monitoring of North Korea with MODIS multi-temporal data based on monthly phenological characteristics. Three frequently used land cover classification algorithms, ISODATA1), SMA2), and SOM3) were employed for this study; the land cover categories were forest, grass, agricultural, wetland, barren, built-up, and water body. The outcomes of the study can be summarized as follows. First, the overall classification accuracy of ISODATA, SMA, and SOM was 69.03%, 64.28%, and 73.57%, respectively. Second, ISODATA and SMA resulted in a higher classification accuracy of forest and agricultural categories, but SOM performed better for the built-up area, bare soil, grassland, and water. A possible explanation for this difference would be related to the difference of sensitivity against the vegetation activity. This would be related to the capability of SOM to express all of their values without any loss of data by maintaining the topology between pixels of primitive data after classification, while ISODATA and SMA retain limited amount of data after normalization process. Third, we can conclude that SOM is the best algorithm for monitoring the land cover change of North Korea.

Policy and Management of Exotic Sika Deer: A Case Study on the Effects of Cervus nippon yesonensis in Tae-an, Republic of Korea

  • Heo, Yoonjeong;Lee, Hyohyemi
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.3 no.2
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    • pp.115-121
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    • 2022
  • The Yezo sika deer (Cervus nippon yesoensis) is a subspecies of sika deer originated from Hokkaido, Japan. This paper is a study on the ecological impact caused by large mammals invading the ecosystem. Two pairs of deer were donated to the Agency for Defense Development in Taean in the late 1980s, and the population expanded to over 280 in 2018. The thermal imaging camera showed that the population ranged from 8 to 53 herds, divided into approximately 10 groups. It was confirmed that some of the herds had escaped the management area and invaded the nearby natural ecosystem, causing damage to cultivated land and natural vegetation. Herds of over 50 individuals have been studied in large grassland areas near drinking water sources such as streams and ponds. In places with excessive deer concentration, 1) feeding damage to herbs, shrubs and sub-trees, 2) tree withering due to antler-rubbing, and their habit of migrating along forest edges 3) excessive soil loss on slopes, 4) destruction of herbaceous layers due to compaction, and finally 5) damage to infrastructure were also investigated. As such, it is expected that the results of this study on the ecological and economic damage of Yezo sika deer can be used to predict the impact of other exotic sika deer in South Korea with similar behavioral characteristics and to establish a management plan.

Studies on Soil Conservation Effects of the Straw-mat Mulching (III) -Effects of the Mat Structures and Its Practicality- (볏짚거적덮기공법(工法)의 사방효과(砂防效果)에 관(關)한 연구(硏究)(III) -거적 밀도(密度)의 영향(影響) 및 공법(工法)의 실용성(實用性)-)

  • Woo, Bo-Myeong
    • Journal of Korean Society of Forest Science
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    • v.27 no.1
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    • pp.5-14
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    • 1975
  • Eroded sloping faces in hillsides including cut-bank slopes are liable to both surface erosion and land-slides and the key to control of these form of erosion lies with drainages of excessive run-off and dense vegetation establishment including surface mulching on the slopes. Micro-plots having $1.6m^2$ (1 metre in width and 1.6 metres in slope length, and 1:1.2 in gradient) of banking slopes on coarse sand soil are used to establish the order of magnititude of the difference in controlling of soil erosion and water runoff, and in rating of survival, performed on the repetetions of three-experiment plots consisted of such three levels as 90% (Dense), 70% (Moderate), and 50% Sparse of the density of the coarse straw-mat mulchings. The main results obtained may be summarized as follows: 1. The rates of surface runoff are calculated as 13.13% from the dense mulchings, 14.21% from the moderate mulchings, and 15.57% from the sparse mulchings respectively. 2. The total amounts of soil loss are measured as about 1.24 tons/ha. from the dense mulchings, about 1.33 tons/ha. from the moderate mulchings, and about 1.44 tons/ha. from the sparse mulchings respectively. The amounts of soil loss under these treatments are much lower than the standard of erosion in USDA (1939 Bennet). 3. Average numbers of germination by treatment are counted as 80 seedlings at the dense mulchings. 132 at the moderates and 121 at the sparse respectively. Large numbers of seedling are suppressed and died during the growing at the dense mulchings due to mainly mechanical obstruction. 4. Coarse straw-mat having about 70% of coverage density is the most suitable mulches in both soil erosion control and vegetation establishment. 5. The method of coarse straw-mat mulching is the most recommendable measure for establishing the vegetation cover with less soil erosion on the denuded gentle slopes in hillsides at present in Korea.

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Troposhperic Ozone Pollutions in Korea during 1998-2002 Using Two Ozone Indices for Vegetation Protection (식생보호를 위한 한계농도 누적 지표로 본 1998-2002년도의 우리나라 대기권 오존 오염)

  • 윤성철;김보선
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.6 no.1
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    • pp.38-48
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    • 2004
  • Tropospheric ozone data in Korea for 1998-2002 were analyzed to assess the impact on vegetation. SUM06(sum of hourly concentrations at or above 0.06 ppm) and AOT40(accumulated exposure over a threshold of 40 ppb), widely used as ozone indices in the U.S. and Europe, were calculated based on hourly ozone concentration in 612 areas during 1998-2002 in Korea. SUM06 of the highest 30 areas were 5-12 ppm/hr which were almost the same levels of the U.S. average, and a crop loss of 5% would be expected. Ozone pollution in Seoul during 1998-2002 had decreased compared to that for 1990-97 except in the Northern area; however, ozone pollution in Kyunggi during 1998-2002 had been increased twice compare to the previous 5 years. Korea was divided into four regions: Seoul Metropolitan area, Jungbu, Honam, and Youngnam. Ozone pollution in the Seoul Metropolitan area was much higher during 1998-2000 than the other areas, but ozone pollution during 2001-2002 was almost the same in all four regions. Chunnam-Kwangyang na Kyungbuk-Gumi, famous industrial complexes in southern Korea, were significant ozone pollution areas. However, other industrial complexes, such as Incheon, Ulsan, and Kyunggi-Sihwa, were not polluted compared to their neighbors. Comparing all ozone indices, SUM06(yr), SUM06(3mon), AOT40(yr), AOT40(3mon), number of hours exceeding 100 ppb, 95 percentile, 99 percentile, and maximum concentration, it was determined reasonable to use SUM06(3mon), AOT40(3mon) and number of hours exceeding 100 ppb for evaluation of the chronic impact of ozone on vegetation.

The Interrelationship between Riparian Vegetation and Hydraulic Characteristics during the 2020 Summer Extreme Flood in the Seomjin-gang River, South Korea (2020 여름 섬진강 대홍수시 하안식생과 수리 특성의 상호관계)

  • Lee, Cheolho;Lee, Keonhak;Kim, Hwirae;Baek, Donghae;Kim, Won;Kim, Daehyun;Lee, Hyunjae;Woo, Hyoseop;Cho, Kang-Hyun
    • Ecology and Resilient Infrastructure
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    • v.8 no.2
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    • pp.79-87
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    • 2021
  • Because active interactions occur among vegetation, hydrology, and geomorphology in riparian systems, any changes in one of these factors can significantly affect the other two. In this study, we evaluated these interactions at four sites (two in Gajeong and two in Hahan) along the Seomjin-gang River that was substantially devastated by an extreme flood in 2020. We examined the relationship between the riparian vegetation and the hydraulic characteristics of the flood using remote sensing, hydraulic modeling, and field surveys combined. The evaluation results showed that the floods caused a record-breaking rise of up to 43.1 m above sea level at the Yeseong-bridge stage gauge station (zero elevation 27.4 m) located between the Gajeong and Hahan sites, with the shear stress being four times higher in Hahan than in Gajeong. Additionally, the water level during the flood was estimated to be a maximum of 1 m higher depending on the location in the presence of riparian plants. Furthermore, both sites underwent extensive biological damage due to the flood, with 78-80% loss in vegetation, with preferential damage observed in large willow species, compared to Quercus acutissima. The above findings imply that all plant species exhibit different vulnerabilities towards extreme floods and do not induce similar behavior towards events causing a disturbance. In conclusion, we developed strategies for effectively managing riparian trees by minimizing flood hazards that could inevitably cause damage.

Development and Application of the Assessment Method of No Net Loss of Greenness for Urban Ecosystem Health Improvement (도시생태계 건전성 증진을 위한 녹지총량 평가법 개발과 적용)

  • Kim, Seung-Hyun;Kong, Hak-Yang;Kim, Tae-Kyu
    • Ecology and Resilient Infrastructure
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    • v.2 no.4
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    • pp.311-316
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    • 2015
  • This study defined and classified no-net-loss-of-greenness (NNLG) based on the law, and then assessed the NNLG index by metropolitan cities and provinces in Korea after estimating NNLG evaluation indicators for the introduction of NNLG for health improvement of urban ecosystems. The results are as follows. First, NNLG was the comprehensive meaning that was included in the greenbelt and park greenbelt and the green area which was defined by the Act on Urban Parks, Greenbelts, etc. and the National Land Planning and Utilization Act respectively. Second, NNLG was classified as a park greenbelt which was included urban parks and greenbelts such as buffer greenbelts, scenic greenbelts, and connecting greenbelts, green areas which was included in green conservation areas, green production areas, green natural areas, and green coverage which is included forests, grasslands, and wetlands that were occupied by vegetation such as trees, shrubs, and plants. Third, NNLG index by cities and provinces was assessed based on the estimation of NNLG evaluation indicators, which included parks and greenbelt areas per capita, green areas per capita, green coverage per capita, ratio of parks and greenbelts, ratio of green areas, and ratio of green coverage. As a result, Sejong city got the highest point of NNLG index and Seoul and Daegu got lowest points of NNLG index among metropolitan cities in Korea. Chungbuk got the highest point of NNLG index and Kyonggi and Jeju got lowest points of NNLG index among provinces in Korea.