• Title/Summary/Keyword: wetland loss

Search Result 51, Processing Time 0.031 seconds

A Study on the Community Characteristics and Changes of Benthic Macroinvertebrates in the Conservation Area of the Shinbulsan Wetland (신불산 고산습지 보호지역 저서성 대형무척추동물의 군집특성 및 변화상 연구)

  • Hong, Sung-Jin;Cheong, Seon-Woo
    • Journal of Environmental Science International
    • /
    • v.29 no.11
    • /
    • pp.1079-1088
    • /
    • 2020
  • The Shinbulsan wetland, located in Yangsan-si, Gyeongsangnam-do, South Korea, was designated as a conservation area in 2004. The area was monitored from 2015 to 2019 to investigate the community characteristics and changes of benthic macroinvertebrates. Between 2015 and 2016, several insects of the orders Ephemeroptera, Odonata, and Hemiptera were identified, but their numbers decreased significantly in 2017 and 2018 following the loss and recovery of the moor owing to drought. During this period, there were relatively more insects of the order Diptera. Within this order, three functional feeding groups, gathering-collectors, plant-piercers, and predators were investigated. Predator species were the most abundant (83.3%), whereas gathering-collectors accounted for the largest proportion of individual insects (50.5%). Between 2015 and 2016, when the moors were stable, groups I and III had the highest community stability. After 2017, when the moors had dried up, group III effectively disappeared because of its lower relative resistance and resilience, and only taxa belonging to group I remained. The results of this study indicate that benthic macroinvertebrates that adapt early during moor formation inhabit the Shinbulsan wetland.

Using GIS to Estimate Estuarine Wetlands in Three Major Estuaries and to Quantify Wetland Changes over the Last Century (GIS를 활용한 하구의 습지추정 및 변화추이 분석에 관한 연구)

  • Rho, Paikho;Lee, Chang-Hee
    • Journal of Wetlands Research
    • /
    • v.9 no.2
    • /
    • pp.21-31
    • /
    • 2007
  • Estuarine wetland, where freshwater meets saltwater, is a transitional ecosystem that is valuable ecologically for a variety of reasons, such as feeding and breeding sites for birds, fish, and wildlife. However, research on the spatial distribution and temporal dynamics of estuarine wetlands in Korea is rare. As a fundamental basis for wetland conservation, this study quantified the wetlands in three major estuaries, and evaluated the temporal dynamics of the wetlands since the 1910s. In particular, this study classified the wetland types into mud flat, sand, and emergent-plant types, and estimated the change of each wetland type, using topographic maps produced in the 1910s, 1970s, and 2000s. The wetlands in both the Han and Youngsan River estuaries have declined since the 1910s, but the rate of wetland decline was relatively low before the 1970s, compared to that since the 1970s. The impact of human activities, such as the Youngsan Watershed Comprehensive Development Project and the construction of estuary barrages, has disrupted the estuary cycles and destroyed huge amounts of wetland in the Youngsan estuary. By contrast, estuarine wetlands have been preserved in the small Gahwa estuary, and provide a variety of habitats for plants and wildlife. A special management strategy for wetlands should be established as soon as possible.

  • PDF

Elicitation of Ecological Wetland's Creating & Maintaining Conditions through GIS & AHP Analysis (GIS와 AHP분석에 의한 생태습지의 생성 및 유지조건 도출)

  • Um, Dae Yong;Shim, Mi Young;Shin, Ke Jong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.31 no.1
    • /
    • pp.29-40
    • /
    • 2013
  • The object of this research is to elicit the ecological wetland's creating and maintaining conditions through GIS and AHP(Analytic Hierarchy Process) on common characteristics of wetland, by exploring the function of the long-standing and naturally created wetlands in South Han-river basin. Geomorphological, geologic, hydraulic & hydrological, pedological, environmental & ecological approaches of five categorizations were made based on the documents and precedent studies in order to perform the research object. Elicitation of the common creating and maintaining conditions on the objected wetlands through analysis of satisfactory conditions was conducted by performing an overlay analysis from the gathered information in each category and linking its result to each wetland. Also, elicitation of highly believable qualified analysis result was made by calculating the each factor's weight through application of AHP analysis method on each factor. The research result is expected to be applied effectively in suitability selection for creation of an artificial wetland and restoration and maintenance for naturally created wetlands when introducing the No Net Loss of Wetlands. In addition, with a new understanding on wetland and beyond the value of its conservativeness, this research result can be considered as a solution for Eco-Wetland's maintainable development.

WETLANDS CONSERVATION AND ITS VISION FOR TAIWAN

  • Chiau, Wen-Yan
    • Proceedings of the Korean Environmental Sciences Society Conference
    • /
    • 2002.05a
    • /
    • pp.29-44
    • /
    • 2002
  • Wetlands provide vital habitats for fish and wildlife while offering numerous other benefits. As in some other countries, however, Taiwan has witnessed the loss of a significant portion of its coastal wetlands due to large-scale reclamation projects along the coast. Most of the wetlands that still remain are seriously being threatened by both human activities and natural changes, such as drainage for agricultural production, filling for industrial development, discharge of wastes and drought. The administrative performance of the existing authorities and legislation in Taiwan has mostly been ineffective in protecting these precious, sensitive areas. This paper introduces the distribution of wetlands in Taiwan and highlights their invaluable functions and potential economic value. It also discussed the recent activities, both initiated by the government and the NGOs, to protect wetlands in Taiwan. Based on the above discussion, the paper identifies the wide-range of current problems related to their management and proposes the vision should have to save wetlands for the future. It argues that establishing clear policies and effective institutional mechanisms on wetland protection and conservation, classifying the wetlands for better management, and fully promoting public awareness and consciousness of the importance of the wetlands will not only be beneficial but will also address the urgent need to safeguard the wetlands in Taiwan. Additionally, the paper recognizes that international cooperation and collaboration on wetland restoration is essential and most challenging.

  • PDF

Functional Assessment of Gangcheon Replacement Wetland Using Modified HGM (수정 수문지형학적 방법을 적용한 강천 대체습지의 기능평가)

  • Kim, Jungwook;Lee, Bo Eun;Kim, Jae Geun;Oh, Seunghyun;Jung, Jaewon;Lee, Myungjin;Kim, Hung Soo
    • Journal of Wetlands Research
    • /
    • v.19 no.3
    • /
    • pp.318-326
    • /
    • 2017
  • Riverine wetlands were reduced and damaged by dredging of rivers and constructing parks in wetlands by Four Rivers Project from 2008 to 2013. Therefore, replacement wetlands were constructed for the compensation of wetland loss by the government. However, It is not enough to manage replacement wetlands. In order to manage the wetlands efficiently, it is necessaty to assess the functions of the wetlands and to manage them according to their functions. Here we performed functional assessments for a replacement wetland called Gangcheon wetland using the modified HGM approach. Hydrological, biogeochemical, animal habitat, and plant habitat functions for the wetland were assessed. To assess the functions, we collected informations for modified HGM approach from the monitored hydrologic data, field survey, published reports and documents for before and after the project, and hydraulic & hydrologic modeling. As the results of the assessment, the hydrological function for the replacement wetland showed 65.5% of the reference wetland, biogeochemical function showed 66.6%, plant habitat function showed 75%, and animal habitat function showed 108.3%. Overall, Gangcheon wetland function after the project was reduced to 78.9% of the function before the project. The decrease in hydrological function is due to the decrease of subsurface storage of water. And the decrease in biogeochemical & pland habitat functions is due to the removal of sandbank around the Gangcheon wetland. To compensate for the reduced function, it is necessary to expand the wetland area and to plant the various vegetation. The modified HGM used in this study can take into account the degree of improvement for replacement wetlands, so it can be used to efficiently manage the replacement wetlands. Also when the wetland is newly constructed, it will be very useful to assess the change of function of the wetland over time.

Spatio-Temporal Dynamics of Estuarine Wetlands Related to Watershed Characteristics in the Han River Estuary (유역특성에 따른 한강하구 습지의 공간분포 및 변화분석)

  • Rho, Paik-Ho
    • Journal of the Korean Geographical Society
    • /
    • v.42 no.3 s.120
    • /
    • pp.344-354
    • /
    • 2007
  • Estuarine wetlands for 33 watersheds in the Han River estuary were delineated on topographic maps from the 1910s, 1970s, and 2000s. Then, these data were used to address the issue of spatial distribution and temporal variation. Watershed characteristics such as drainage density, location, watershed size, slope, and elevation were identified for each watershed to determine the relationship between watershed characteristics and spatial distribution of estuarine wetlands. The analysis of estuarine wetlands indicated that wetlands in the estuary had declined gradually between the 1910s and the 1970s, although most wetlands were lost since the 1970s mainly caused by the large development projects related to urban expansion in metropolitan Seoul. The sediment composition and formation processes of the wetlands differed with watershed location; mud flats dominate in the lower part of the estuary, and relatively more sandy and emergent-plant wetlands occur near the main channel and tributaries of the Han River. Relatively more estuary wetlands occur in large watersheds, which have high slopes and low elevations. Estuarine wetlands have been lost dramatically in the densely populated watershed regions (i.e., Han River Seoul, Han River Goyang, West Han River), while relatively more wetlands have remained in undeveloped regions, including the Lower Imjin River and Lower Han River. In particular, anthropogenic disturbance has played an important role in the loss of wetland through the conversion of wetland into agricultural and developed land.

Spatial Distribution and Social Characteristics for Wetlands in Gyeongsangnam-do Province (경상남도 내 습지의 공간 분포 및 사회적 특성)

  • Do, Yu-No;Kim, Ji-Yoon;Im, Ran-Young;Kim, Seong-Bo;Choi, Jong-Yoon;Joo, Gea-Jae
    • Korean Journal of Ecology and Environment
    • /
    • v.45 no.2
    • /
    • pp.252-260
    • /
    • 2012
  • The wetlands have eco-sociological values because their functions have proven to be useful to human society. Many countries are working to conserve and protect the wetland ecosystems. However, many wetlands have disappeared or have been fragmented due to a natural and/or anthropogenic disturbance. These isolated wetlands appear to work best in the landscape, as a spatially distributed system. We have analyzed the spatial-social distribution patterns of wetlands in Gyeongsangnam-do Province (GNP). We examined the frequency distribution of wetland sizes, the distances to the nearest wetlands, the shapes of the wetlands, land-use patterns, land owners, and official land values were confirmed as social characteristics for each wetland. A total of 146 wetlands (3,598.85 ha), including 76 riverine wetlands (1,955.60 ha), 49 palustrine wetlands (1,282.28 ha) and 21 mountain wetlands (1,282.28 ha) were identified in GNP. Most wetlands left for use to drainage were small (<2 ha) and located in agricultural areas. However, small and isolated wetlands were clustered, according to the location, indicating that these wetlands can be connected to each other using the linear riverine wetlands and water channels in agricultural areas. This is extremely valuable in maintaining the biodiversity, such that any loss of small wetlands will cause a direct reduction in the connectedness among populations of the remaining species. Due to most wetlands belonging to the nation or businesses, being classified as reservoirs (water storage areas), and consequently, degradation of wetlands will progress due to grand-scale engineering works. Therefore, wetland policy and ecologically sensitive laws and policies should be developed in order to promote the wise-use for wetlands.

The Optimal Environmental Ranges for Wetland Plants: II. Scirpus tabernaemontani and Typha latifolia

  • Lee, Bo-Ah;Kwon, Gi-Jin;Kim, Jae-Geun
    • Journal of Ecology and Environment
    • /
    • v.30 no.2
    • /
    • pp.151-159
    • /
    • 2007
  • We studied the optimal ranges of water and soil characteristics for wetland plants, particularly Scirpus tabernaemontani (softstem bulrush) and Typha latifolia (broadleaf cattail), which are dominant species with potential for restoration of Korean wetlands. We observed vegetation in S. tabernaemontani and T. latifolia communities from the mid to late June, 2005, and measured characteristics of water environments such as water depth (WD), temperature (WT), conductivity (WC), and concentration of several ions $(NO_3{^-}-N,\;Ca^{2+},\;Na^+,\;Mg^{2+},\;and\;K^+)$, and characteristics of soil environments such as soil texture, organic matter (loss on ignition, LOI), conductivity, and pH. The S. tabernaemontani community was accompanied by Zizania latifolia (Manchurian wildrice), Persicaria thunbergii (Korean persicary), Actinostemma lobatum (lobed actinostemma), and Beckmannia syzigachne (American slough grass), while the T. latifolia community was accompanied by P. thunbergii, T. angustifolia (narrowleaf cattail), and Glycine soja (wild soybean). We defined the optimal range for distribution (ORD) as the range that each plant was crowded. The optimal range of water characteristics for the S. tabernaemontani community was a $WD\;10{\sim}50cm,\;WT\;24.0{\sim}32.0^{\circ}C,\;WC\;100{\sim}500{\mu}S/cm,\;{NO_3}{^-}-N\;0{\sim}60ppb,\;K^+\;0.00{\sim}1.50ppm,\;Ca^{2+}\;7.50{\sim}17.50ppm,\; Na^+\;2.50{\sim}12.50ppm,\;and\;Mg^{2+}\;3.00{\sim}7.00ppm$. In addition, the optimal range of soil characteristics for the S. tabernaemontani community was a soil texture of loam, silty loam, and loamy sand, $LOI\;8.0{\sim}16.0%,\;pH\;5.25{\sim}6.25$, and conductivity $10{\sim}70{\mu}S/cm$. The optimal range of water characteristics for the T. latifolia community was a $WD\;10{\sim}30cm,\;WT\;22.5{\sim}27.5^{\circ}C,\;WC\;100{\sim}400{\mu}S/cm,\;{NO_3}{^-}-N\;0{\sim}60ppb,\;K^+\;0.00{\sim}1.50ppm,\;Ca^{2+}\;0.00{\sim}17.50ppm,\;Na^+\;0.00{\sim}12.50ppm,\;and\;Mg^{2+}\;0.00{\sim}5.00ppm$, and the optimal range of soil characteristics for the T. fatifolia community was a soil texture of loam, sandy loam, and silty loam, LOI $3.0{\sim}9.0%,\;pH\;5.25{\sim}7.25$, and conductivity $0{\sim}70{\mu}S/cm$.

Significance of Biomarkers in the Assessment of Dredged Materials for Beneficial Reuses and Disposal (준설물질 유효활용 및 처분을 위한 평가에 있어 생체지표 활용의 재고)

  • Won, Eun-Ji;Choi, Jin Young;Kim, Kyoungrean
    • Journal of Environmental Impact Assessment
    • /
    • v.25 no.6
    • /
    • pp.466-476
    • /
    • 2016
  • Dredging is inevitably necessary for the management of water infrastructure such as waterways and polluted bottom sediment. Dredged material management options may be offshore dumping, wetland creation, beach nourishment and various other engineering uses depending on the given circumstances at the time of dredging. Among those options, wetland creation and beach nourishment are the preferred ones in Korea considering significant loss of wetland and beach erosion due to various development projects along the coastal region. In order to use dredged material beneficially, however, dredged material needs to be assessed its suitability with respect to its engineering purpose and environmental criteria. In this paper, we demonstrate that environmental risk of dredged material to be introduced into the marine environment can be easily assessed using biomarkers with relative low cost. Biomarkers can also compliment pollutant contents analysis that may not be specific to their impact on biological response. Biomarker information may be used to assist decision making process in selecting suitable treatment or beneficial use options for dredged materials.

Effects of soil water content and light intensity on the growth of Molinia japonica in montane wetlands in South Korea

  • Choi, Yu Seong;Park, Hyun Jun;Kim, Jae Geun
    • Journal of Ecology and Environment
    • /
    • v.45 no.1
    • /
    • pp.17-23
    • /
    • 2021
  • Background: Montane wetlands are unique wetland ecosystems with distinct physicochemical characteristics, and Molinia japonica often makes dominant communities in montane wetlands in South Korea. In order to figure out the environmental characteristics of M. japonica habitats and the major factors for the growth of M. japonica, field surveys were conducted in five wetlands from September to October 2019. Also, soil was collected at every quadrats installed in surveyed wetlands to analyze the physicochemical features. Results: The relative coverage of M. japonica was higher in low latitude wetlands than in high latitude. Redundancy analysis showed that soil water content had the strongest effect on the growth of M. japonica (F = 23.0, p < 0.001). Soil water content, loss on ignition, and relative light intensity showed a high correlation with the density (R = 0.568, 0.550, 0.547, respectively, p < 0.01) and the coverage of M. japonica (R = 0.495, 0.385, 0.514, respectively, p < 0.01). Soil water content, loss on ignition, and pH were highly correlated with each other. Conclusions: Molinia japonica lives in acidic wetlands at high altitude in temperate zone of low latitude, with peat layer placed on the floor. Also, M. japonica prefers open spaces to secure enough light for photosynthesis. High shoot production of M. japonica resulted in adding new peat material in every year, and this layer enforces the environmental characteristics of M. japonica habitats. This study may provide insights for further understanding of the method how wetlands maintain acidic condition by itself in montane wetlands in temperate zone.