• Title/Summary/Keyword: ecosystems

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Estimating carbon dioxide uptake in wetland ecosystems of Tumen River Basin using eddy covariance flux data (에디 공분산 기반의 플럭스 타워 관측자료를 이용한 두만강 유역 습지 생태계 CO2 흡수량 분석)

  • Chen, Pengshen;Zhao, Shuqing;Cui, Guishan;Lee, Dongkun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.27 no.3
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    • pp.67-74
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    • 2024
  • In the context of rapid temperature rise in mid-to-high latitude regions, cold region wetlands have become a hotspot for current wetland carbon cycle research due to their high sensitivity to climate change. Strengthening the monitoring of CO2 fluxes in wetland ecosystems is of great practical significance for clarifying the carbon balance of wetlands and maintaining the ecological balance of wetland ecosystems in China's high latitude regions. In this study, the carbon flux (NEE, Net ecosystem exchange; GPP, Gross Primary Production; RECO, Ecosystem response) of Jingxin Wetland was monitored by eddy correlation method from August 2021 to March 2024.2022-2023 shows CO2 sinks, absorbing 349.4 g C·m-2·yr-1 annually. The correlation analysis showed that Ta, VPD and PPFD were the main environmental factors affecting CO2 flux in Jingxin wetland.

A comprehensive review of Coreopsis lanceolata: assessing its invasion risk and ecological impact

  • Eunhee Cho;Deokjoo Son
    • Journal of Ecology and Environment
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    • v.48 no.3
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    • pp.285-295
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    • 2024
  • Although invasive alien species (IAS) have a negative impact on native ecosystems and reduce ecosystem services and productivity, the understanding of IAS at the population level is still lacking. Coreopsis lanceolata, a perennial plant native to North America, is expanding its invasive range, but there is limited research on the invasion risk of this species, and measures to control its spread are inadequate. Therefore, we collected findings from selected studies on C. lanceolata, examining its morphological and growth characteristics, reproductive traits, and invasion strategies, sourced from scientific databases using its scientific name as the keyword. Researchers have conducted extensive research on C. lanceolata, primarily focusing on the extraction of chemical compounds for anticancer and antioxidant effects and numerous studies on seed germination conditions in the field of ecology. Coreopsis lanceolata has a negative impact on plant ecosystems in Australia and Japan, and its high invasiveness is associated with high seed production, high seed viability and longevity, rapid reproduction through rhizomes, high surface coverage, and long flowering periods. Few studies have examined the invasive potential of C. lanceolate and management techniques to stop its spread, despite worries about the detrimental effects of invasion on plant ecosystems. Therefore, additional research on the invasion risk and management of C. lanceolata is necessary. This review offers a thorough analysis of C. lanceolata, serving as a scientific foundation for devising future ecosystem management strategies.

Flow Regime Boundary for Restoring River Ecosystems: A Case of the Han River Basin (하천 생태계 복원을 위한 적정 유황 범위 고찰: 한강유역사례)

  • Kang, Seongkyu;Lee, Dong-Ryul;Choi, Sijung
    • Journal of Wetlands Research
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    • v.21 no.spc
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    • pp.1-8
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    • 2019
  • River works for water utilization have substantially altered the natural flow regime, and it has resulted in deformation of healthy river ecosystems. In Korea, river restoration projects have conducted actively since 1990's. Major purposes of the river restoration are the rehabilitation of modified river channel, improvement of water quality, and creation of aquatic habitats as well as recreational spaces using natural material for river work. However, there have been little interests about the restoration of flow regime which influences to most aspects of river ecosystems. The restoration of natural flow regime has received much attention in preservation of aquatic ecosystems. It should be needed to explore the relationship between flow regime and river ecosystems, and the restoring flow regime is essential. This paper introduce the concept of environmental flow through the interrelation between flow regime and river ecosystem. It provides rolls of flow regime and addresses the method of establishing target flow regime using the RVA(Range of Variability Approach) that suggested by Richter et al.(1997) through analysis of altered flow pattern case of Han river basin.

Characteristics of accumulated soil carbon and soil respiration in temperate deciduous forest and alpine pastureland

  • Jeong, Seok-Hee;Eom, Ji-Young;Park, Ju-Yeon;Lee, Jae-Ho;Lee, Jae-Seok
    • Journal of Ecology and Environment
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    • v.42 no.1
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    • pp.20-29
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    • 2018
  • Background: For various reasons such as agricultural and economical purposes, land-use changes are rapidly increasing not only in Korea but also in the world, leading to shifts in the characteristics of local carbon cycle. Therefore, in order to understand the large-scale ecosystem carbon cycle, it is necessary first to understand vegetation on this local scale. As a result, it is essential to comprehend change of the carbon balance attributed by the land-use changes. In this study, we attempt to understand accumulated soil carbon (ASC) and soil respiration (Rs) related to carbon cycle in two ecosystems, artificially turned forest into pastureland from forest and a native deciduous temperate forest, resulted from different land-use in the same area. Results: Rs were shown typical seasonal changes in the alpine pastureland (AP) and temperate deciduous forest (TDF). The annual average Rs was $160.5mg\;CO_2\;m^{-2}h^{-1}$ in the AP, but it was $405.1mg\;CO_2\;m^{-2}h^{-1}$ in the TDF, indicating that the Rs in the AP was lower about 54% than that in the TDF. Also, ASC in the AP was $124.49Mg\;C\;ha^{-1}$ from litter layer to 30-cm soil depth. The ASC was about $88.9Mg\;C\;ha^{-1}$, and it was 71.5% of that of the AP. The temperature factors in the AP was high about $4^{\circ}C$ on average compared to the TDF. In AP, it was observed high amount of sunlight entering near the soil surface which is related to high soil temperature is due to low canopy structure. This tendency is due to the smaller emission of organic carbon that is accumulated in the soil, which means a higher ASC in the AP compared to the TDF. Conclusions: The artificial transformation of natural ecosystems into different ecosystems is proceeding widely in the world as well as Korea. The change in land-use type is caused to make the different characteristics of carbon cycle and storage in same region. For evaluating and predicting the carbon cycle in the vegetation modified by the human activity, it is necessary to understand the carbon cycle and storage characteristics of natural ecosystems and converted ecosystems. In this study, we studied the characteristics of ecosystem carbon cycle using different forms in the same region. The land-use changes from a TDF to AP leads to changes in dominant vegetation. Removal of canopy increased light and temperature conditions and slightly decreased SMC during the growing season. Also, land-use change led to an increase of ASC and decrease of Rs in AP. In terms of ecosystem carbon sequestration, AP showed a greater amount of carbon stored in the soil due to sustained supply of above-ground liters and lower degradation rate (soil respiration) than TDF in the high mountains. This shows that TDF and AP do not have much difference in terms of storage and circulation of carbon because the amount of carbon in the forest biomass is stored in the soil in the AP.

Estimating carbon uptake in forest and agricultural ecosystems of Korea and other countries using eddy covariance flux data (에디 공분산 기반의 플럭스 타워 관측자료를 이용한 국내외 산림과 농업 생태계 탄소 흡수량 분석)

  • Lee, Bora;Kang, Wanmo;Kim, Choong-Ki;Kim, Gieun;Lee, Chang-Hoon
    • Journal of Environmental Impact Assessment
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    • v.26 no.2
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    • pp.127-139
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    • 2017
  • Measurements of net ecosystem exchange (NEE) of $CO_2$ based on the eddy covariance technique provide reasonable carbon balance estimates in response to local environmental conditions. In South Korea, the forest ecosystems cover approximately 64% of the total area, thereby strongly affecting regional carbon balances. Cultivated croplands that cover about 17% of the total area should also be considered when calculating the carbon balance of the country. In this study, our objectives were (a) to quantify the range and seasonal variation of NEE at forest ecosystems, including deciduous, coniferous, and mixed forests, and agricultural ecosystems, including rice paddies and a potato field, in South Korea and (b) to compare NEE at ten Fluxnet sites that have the same or similar ecosystems as found in South Korea. The results showed that the forest and agricultural ecosystems were carbon sinks. In Korea, NEE at the forest ecosystems varied between -31 and $-362gC/m^2/yr$, and NEE at the croplands ranged from -210 to $-248gC/m^2/growing$ season. At the deciduous forest, NEE reached low values in late spring, early summer, and early autumn, while at the coniferous forest, it reached low values in spring, early summer, and mid autumn. The young mixed forest was a much stronger carbon sink than the old-growth deciduous and coniferous forests. During each crop growing season, beet had the lowest NEE value within six crops, followed by wither wheat, maize, rice, potato, and soybean. These results will be useful for designing and applying management strategies for the reduction of $CO_2$ emissions.