• Journal of Forest and Environmental Science
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• v.26 no.2
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• pp.65-73
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• 2010

Biodiversity, referring to the variety and abundance of species, their genetic composition, and the communities, ecosystem, and landscapes, is essential to maintain healthy and productive forests, and to provide useful hedge against the future uncertainties in conditions of the environment and natural resources. To realize the long-term sustainability for forest production of goods and services is dependent upon maintaining and enhancing the biodiversity in the forest ecosystem. Because we can not always recognized which portion of biodiversity is essential to maintain the stability and sustainability of the natural system, conserving biodiversity is even unconditionally important. Even though the activities of forest resource management may have a variety of negative impacts on biodiversity by modification of the natural ecosystem into economically effective artificial ecosystem, forest professionals have been developing intelligent scheme to coexist management and conservation. However, conservation of biodiversity must be a complex problem encircled by ecological, economical, and social considerations. There seems to be no such a simple and easy solution. Strategies for ecologically deliberated forest resource management, which could play an important role to conserve biodiversity, were discussed.

• 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.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.4
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• pp.459-468
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• 2013

In the application of the ecosystem-based fisheries assessment Jeonnam marine ranching ecosystem, two fisheries, funnel fishery and trap fishery, were selected as target fisheries. Black seabream, Acanthopagru schlegelii, rock bream, Sebastes inermis, gray mullet, Mugil cephalus, were selected as target species for the funnel fishery, and conger eel, Conger myriaster, was target species for the trap fishery. For assessing indicators of four management objectives, that is the maintenance of sustainability, biodiversity, habitat quality and socio-economic benefits, indicators were selected considering the availability of data, which were 5 indicators for sustainability, 3 indicators for biodiversity, 4 indicators for habitat, 2 indicators for socio-economic benefit. The Objective risk indices for sustainability and biodiversity of two fisheries were estimated at yellow zone, medium risk level. The objective risk indices for habitat and socio-economic benefit were estimated at green zone, safe level. The species risk indices (SRI) were estimated at yellow zone. The fishery risk indices (FRIs) were estimated at 1.143 and 1.400 for funnel net fishery and trap fishery, respectively. Finally the ecosystem risk index estimated at 1.184.

• Korean Journal of Environment and Ecology
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• v.36 no.6
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• pp.684-692
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• 2022

This study was conducted to assess ecosystem services provided for Saemangeum agricultural and life sites and surrounding areas and establish measures to enhance them. The ecosystem services in the Saemangeum region were found to be different depending on its land use type. Before reclamation, the quality of ecosystem service in the Saemangeum region was high in all aspects: supply, control, culture, and support service functions. After the reclamation, however, the quality of supply, regulating, and support services declined. Therefore, it is necessary to enhance the quality of regulating and support services provided by semi-natural habitats such as rice paddy and reservoirs to improve the ecosystem service of the Saemangeum agricultural and life site. The suggested service improvement includes transforming natural ecosystems, such as forests and rural areas, and vast agricultural land into rural tourism and ecotourism and strengthening cultural service functions centered on education and research related to agriculture. To this end, it is necessary to utilize large agricultural land and agricultural infrastructure to promote agricultural production and rural tourism and government support for areas where the aging population is a problem.

• Journal of Ecology and Environment
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• v.38 no.4
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• pp.425-436
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• 2015

The carbon cycle came into the spotlight due to the climate change and forests are well-known for their capacity to store carbon amongst other terrestrial ecosystems. The annual organic carbon of litter production, forest floor litter layer, soil, aboveground and belowground part of plant, standing biomass, net primary production, uptake of organic carbon, soil respiration, etc. were measured in Mt. Worak in order to understand the production and carbon budget of Quercus serrata forest that are widely spread in the central and southern part of the Korean Peninsula. The total amount of organic carbon of Q. serrata forest during the study period (2010-2013) was 130.745 ton C ha^-1. The aboveground part of plant, belowground part of plant, forest floor litter layer, and organic carbon in soil was 50.041, 12.510, 4.075, and 64.119 ton C ha^-1, respectively. The total average of carbon fixation in plants from photosynthesis was 4.935 ton C ha^-1 yr^-1 and organic carbon released from soil respiration to microbial respiration was 3.972 ton C ha^-1 yr^-1. As a result, the net ecosystem production of Q. serrata forest estimated from carbon fixation and soil respiration was 0.963 ton C ha^-1 yr^-1. Therefore, it seems that Q. serrata forest can act as a sink that absorbs carbon from the atmosphere. The carbon uptake of Q. serrata forest was highest in stem of the plant and the research site had young forest which had many trees with small diameter at breast height (DBH). Consequentially, it seems that active matter production and vigorous carbon dioxide assimilation occurred in Q. serrata forest and these results have proven to be effective for Q. serrata forest to play a role as carbon storage and NEP.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.1
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• pp.13-20
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• 2013

An emergy concept was used to evaluate the contributions of the Youngsan River Estuary to the Korean economy from systems and ecosystem service perspectives. Total emergy input to the estuary was $9.42{\times}10^{20}$ sej/yr with the chemical potential of river inflow accounting for 73% of the total and tidal energy for the remaining 27%, reflecting the unique environmental characteristics of estuaries where rivers meet sea. From the systems perspective, the estuary ecosystem contributed 179.9 billion em\/yr (14.91 million em\/ha/yr or 13,526 em$/ha/yr). Four ecosystem services of the Youngsan River Estuary were selected for the emergy evaluation: fishery production, pollutant removal, aesthetic function, and scientific research information. Aesthetic function contributed the most to the Korean economy with 179.9 billion em\/yr, followed by fishery production (101.1 billion em\/yr), pollutant removal (32.6 billion em\/yr), and scientific research information (934 million em\/yr). Emergy-based values of the selected ecosystem services of the estuary were higher than those calculated by economic methodologies.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.1
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• pp.84-92
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• 1999

The rumen microbial ecosystem is coming to be recognized as a rich alternative source of genes for industrially useful enzymes. Recent advances in biotechnology are enabling development of novel strategies for effective delivery and enhancement of these gene products. One particularly promising avenue for industrial application of rumen enzymes is as feed supplements for nonruminant and ruminant animal diets. Increasing competition in the livestock industry has forced producers to cut costs by adopting new technologies aimed at increasing production efficiency. Cellulases, xylanases, ${\beta}$-glucanases, pectinases, and phytases have been shown to increase the efficiency of feedstuff utilization (e.g., degradation of cellulose, xylan and ${\beta}$-glucan) and to decrease pollutants (e.g., phytic acid). These enzymes enhance the availability of feed components to the animal and eliminate some of their naturally occurring antinutritional effects. In the past, the cost and inconvenience of enzyme production and delivery has hampered widespread application of this promising technology. Over the last decade, however, advances in recombinant DNA technology have significantly improved microbial production systems. Novel strategies for delivery and enhancement of genes and gene products from the rumen include expression of seed proteins, oleosin proteins in canola and transgenic animals secreting digestive enzymes from the pancreas. Thus, the biotechnological framework is in place to achieve substantial improvements in animal production through enzyme supplementation. On the other hand, the rumen ecosystem provides ongoing enrichment and natural selection of microbes adapted to specific conditions, and represents a virtually untapped resource of novel products such as enzymes, detoxificants and antibiotics.

• Journal of Environmental Science International
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• v.8 no.5
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• pp.575-586
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• 1999

From the environmental aspects, primary productivity of phytoplankton plays the most improtant role in enhancement of marine culture oyster production. This study may be divided into two branches; one is estimation of maximum oyster meat production per unit facility(Carrying Capacity) under the present enviromental conditions in Kamak Bay, the other is improvement of carrying from increase of primary productivity by changing the environmental conditions that cause not ot form an unfavorable environment such as the formation of oxygen deficient water mass using the eco-hydrodynamic model. By simulation of three-dimensional hydrdynamic model and ecosystem model, the comparison between observed and computed data showed good agreement. The results of sensitivity analysis showed that phytoplankton maximum growth rate was the most important parameter for phytoplankton and dissolved oxygen. The estimation of mean primary productivity of Wonpo, Kamak, Pyongsa, and Kunnae culture grounds in Kamak Bay during culturing period were 3.73gC/$m^2$/d, 2.12gC/$m^2$/d, 1.98gC/$m^2$/d, and 1.26gC/$m^2$/d, respectively. Under condition not ot form the oxygen deficient water mass, four times increasing of pollutants loading as much as the present loading from river increased mean primary productivity of whole culture grounds to 4.02gC/$m^2$/d. Sediment N, P fluxes that allowed for 35% increasing from the present conditions increased mean primary productivity of whole culture grounds to 3.65gC/$m^2$/d. Finally, ten times increasing of boundary loadings from the present conditions increased mean primary productivity of whole culture grounds to 3.95gC/$m^2$/d. The maximum oyster meat production per year and that of unit facility in actual oyster culture grounds under the present conditions were 6,929ton and 0.93ton, respectively. This 0.93ton/unit facility is considered to be the carrying capacity in study area, and if the primary productivity is increased by changing the environmental conditions, oyster production can be increased.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.4
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• pp.307-316
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• 2010

Complex terrain refers to irregular surface properties of the earth that influence gradients in climate, lateral transfer of materials, landscape distribution in soils properties, habitat selection of organisms, and via human preferences, the patterning in development of land use. Complex terrain of mountainous areas represents ca. 20% of the Earth's terrestrial surface; and such regions provide fresh water to at least half of humankind. Most major river systems originate in such terrain, and their resources are often associated with socio-economic competition and political disputes. The goals of the TERRECO-IRTG focus on building a bridge between ecosystem understanding in complex terrain and spatial assessments of ecosystem performance with respect to derived ecosystem services. More specifically, a coordinated assessment framework will be developed from landscape to regional scale applications to quantify trade-offs and will be applied to determine how shifts in climate and land use in complex terrain influence naturally derived ecosystem services. Within the scope of TERRECO, the abiotic and biotic studies of water yield and quality, production and biodiversity, soil processing of materials and trace gas emissions in complex terrain are merged. There is a need to quantitatively understand 1) the ecosystem services derived in regions of complex terrain, 2) the process regulation occurred to maintain those services, and 3) the sensitivities defining thresholds critical in stability of these systems. The TERRECO-IRTG is dedicated to joint study of ecosystems in complex terrain from landscape to regional scales. Our objectives are to reveal the spatial patterns in driving variables of essential ecosystem processes involved in ecosystem services of complex terrain region and hence, to evaluate the resulting ecosystem services, and further to provide new tools for understanding and managing such areas.

• Ocean Science Journal
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• v.41 no.2
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• pp.121-124
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• 2006

Argo drifters provide information of the vertical structure in the water column and have a potential for the improvement of understanding phytoplankton primary production and biogeochemical cycles in combination with ocean color satellite data, which can obtain the horizontal distribution of phytoplankton biomass in the surface layer. Our examples show that using Argo drifters with satellite-measured horizontal distribution of phytoplankton biomass at the sea surface allow an improved understanding of the development of the spring bloom. The other possible uses of Argo drifter are discussed.