간행물

생태와 환경 KCI 등재 Korean Journal of Ecology and Environment

권호리스트/논문검색
이 간행물 논문 검색

권호

Vol. 50 No. 1 (2017년 3월) 14

1.
2017.03 구독 인증기관 무료, 개인회원 유료
Daecheong Reservoir was made by the construction of a large dam (>15 m in height) on the middle to downstream of the Geum River and the discharge systems have the watergate-spillway (WS), a hydropower penstock (HPP), and two intake towers. The purpose of this study was to investigate the limnological anomalies of turbid water reduction, green algae phenomenon, and oligotrophic state in the lower part of reservoir dam site, and compared with hydro-meteorological factors. Field surveys were conducted in two stations of near dam and the outlet of HPP with one week intervals from January to December 2000. Rainfall was closely related to the fluctuations of inflow, outflow and water level. The rainfall pattern was depended on the storm of monsoon and typhoon, and the increase of discharge and turbidity responded more strongly to the intensity than the frequency. Water temperature and DO fluctuations within the reservoir water layer were influenced by meteorological and hydrological events, and these were mainly caused by water level fluctuation based on temperature stratification, density current and discharge types. The discharges of WS and HPP induced to the flow of water bodies and the outflows of turbid water and nutrients such as nitrogen and phosphorus, respectively. Especially, when hypoxic or low-oxygen condition was present in the bottom water, the discharge through HPP has contributed significantly to the outflow of phosphorus released from the sediment into the downstream of dam. In addition, HPP effluent which be continuously operated throughout the year, was the main factor that could change to a low trophic level in the downreservoir (lacustrine zone). And water-bloom (green-tide) occurring in the lower part of reservoir was the result that the water body of upreservoir being transported and diffused toward the downreseroir, when discharging through the WS. Finally, the hydropower effluent was included the importance and dynamics that could have a temporal and spatial impacts on the physical, chemical and biological factors of the reservoir ecosystem.
4,800원
2.
2017.03 구독 인증기관 무료, 개인회원 유료
In an aquatic environment, toxicity of metals to organisms depends on external factors (type of metal, exposure concentration and duration, environmental parameters, and water quality) and intracellular processes (metal-binding sites and detoxification). Toxicity of copper (Cu) on the marine microalga Tetraselmis suecica was investigated in this study. Dose-dependent (Cu concentration dependent) inhibition of growth and cell division, as well as, variation of intra- and extra-cellular Cu, Fe and Zn content was observed. T. suecica was sensitive to Cu; the 96 h EC50 (concentration to inhibit growth-rate by 50%) of growth rate (μ) (21.73 μM L-1), cell division day-1 (18.39 μM L-1), and cells mL-1 (13.25 μM L-1) demonstrate the toxicity of Cu on this microalga. High intra- (19.86 Pg cell-1) and extra-cellular (54.73 Pg cell-1) Cu concentrations were recorded, on exposure to 24.3 and 72.9 μM L-1 of Cu.
4,500원
3.
2017.03 구독 인증기관 무료, 개인회원 유료
This study explored spatiotemporal variability of water quality in correspondence with hydrometeorological factors in the four stations of Euiam Reservoir located in the upstream region of the North-Han River from May 2012 to December 2015. Seasonal effect was apparent in the variation of water temperature, DO, electric conductivity and TSS during the study period. Stratification in the water column was observed in the near dam site every year and vanished between August and October. Increase of nitrogen nutrients was observed when inflowing discharge was low, while phosphorus increase was distinct both during the early season with increase of inflowing discharge and the period of severe draught persistent. Duration persisting high concentration of Chl-a (>25 mg m-3: the eutrophic status criterion, OECD, 1982) was 1~2 months of the whole year in 2014~2015, while it was almost 4 months in 2013. Water quality of Euiam Reservoir appeared to be affected basically by geomorphology and source of pollutants, such as longitudinally linked instream islands and Aggregate Island, inflowing urban stream, and wastewater treatment plant discharge. While inflowing discharge from the dams upstream and outflow pattern causing water level change seem to largely govern the variability of water quality in this particular system. In the process of spatiotemporal water quality change, factors related to climate (e.g. flood, typhoon, abruptly high rainfall, scorching heat of summer), hydrology (amount of flow and water level) might be attributed to water pulse, dilution, backflow, uptake, and sedimentation. This study showed that change of water quality in Euiam Reservoir was very dynamic and suggested that its effect could be delivered to downstream (Cheongpyeong and Paldang Reservoirs) through year-round discharge for hydropower generation.
5,100원
4.
2017.03 구독 인증기관 무료, 개인회원 유료
The Youngsan River estuary was physically changed by the construction of a sea embankment at near the mouth of estuary. Weirs were also constructed recently in the freshwater zone and it was reported that algal blooms occur more frequently. The freshwater introduced into saltwater zone from sluice gates of the embankment affects water quality but it has not been addressed that how the freshwater inputs influence the health of marine ecosystem. In this study, we used the data of water properties and phytoplankton communities collected at three stations for 4 days including before the freshwater discharge, during the discharge and after 1 and 2 days of discharge events. WQI (water quality index), TRIX (trophic status index) and P-IBI (phytoplankton index of biotic integrity) were used to evaluate the ecosystem health and long-term data were also utilized to determine the criteria for P-IBI. The results showed that grades of the ecosystem health assessed by the indices were low at the station near the gates and increased as downstream. However, the temporal pattern of grades was different depending on methods. Grades of WQI and TRIX decreased during the discharge and restored after the discharge whereas the grades of P-IBI decreased slightly even after the discharge. This suggests that P-IBI is more applicable to estuarine systems where experience extreme change of water properties than WQI and TRIX since P-IBI includes phytoplankton that can respond quickly to the change.
4,200원
5.
2017.03 구독 인증기관 무료, 개인회원 유료
Overwintering and succession of phytoplankton community with physicochemical and biological characteristics were investigated in pilot culture system. Water and phytoplankton samples were collected twice a week from February 23 to June 28, 2016. A total of 17 overwintering taxa including cyanophyceae, chlorophyceae, bacillariophyceae were identified in the experimental group in winter (February), and these overwintering species showed a marked succession pattern along with environment changes. In the process of phytoplankton succession, a total of 56 species in 28 genera were identified in two (experimental, control) pilot culture system. In the experimental group, 52 phytoplankton species in 24 genera were identified, and the number of taxa was highest in chlorophyceae (35 species), followed by Bacillariophyceae (9 species), Cyanophyceae (5 species) and others (3 species). In the control group, 25 phytoplankton species in 14 genera were classified and these taxa consisted of 17 chlorophyceae, 3 cyanophyceae, 2 Bacillariophyceae and 3 others. The standing crops ranged from 40 to 325,450 cells mL-1 in the experimental group, and from 900 to 37,100 cells mL-1 in the control group, respectively. The dominant species were represented by Monoraphidium minutum, Microcystis aeruginosa, Rhodomonas lacustris, Ankyra judai and Chlorella vulgaris in the experimental group; and M. minutum and Coenochloris cf. pyrenoidosa in the control group. In conclusion, overwintering and succession of predominant phytoplankton species developed due to interactions of internal environmental factors (physicochemical and biological factors) in the pilot culture system.
4,500원
6.
2017.03 구독 인증기관 무료, 개인회원 유료
The Hwasan wetland vegetation is observed at mountain basin (644~780 m a.s.l.) where had become a potential land for indigenous people since prehistoric period. We phytosociologically investigated old-growth alder (Alnus japonica) forests using the Zürich-Montpellier School’s method and analyzed their spatial distribution pattern by actual vegetation map. Species performance was determined by using coverage and r-NCD. Viburnum opulus var. calvescens-Alnus japonica community syntaxonomically belonging to the Alnetea japonicae was first described and composed of three subunits: Salix koreensis subcommunity, typical subcommunity, and Pyrus ussuriensis subcommunity. Present plant community was compared with vicariant syntaxa such as Molinia japonica-Alnus japonica community, Rhamno nipponicae-Alnetum japonicae, and Aceri-Salicetum koreensis. Hwasan’s alder forest, an alluvial terrace vegetation type on valley fan in the montane zone, is evaluated as vegetation class [I], which is a sort of benchmark plant community potentially on mountain wetlands in southeastern part of the Korean Peninsula. Simultaneously we suggested an establishment of the national strategy for habitat conservation free from hydrologically radical transform due to military utilization.
4,000원
7.
2017.03 구독 인증기관 무료, 개인회원 유료
Euiam and Paldang Reservoirs have often been facing water quality problems, such as eutrophication, algal blooms and off-flavors by treated wastewater effluent (TWE) in the North-Han and the Han River basins, but little is examined on the direct biological effect of TWE. This study tested algal growth potential (AGP) of four TWEs discharged into Euiam and Paldang Reservoirs to evaluate water fertility in September 2014 and March and September 2015. Test alga was used Anabaena circinalis isolated from Paldang Reservoir. Mean concentration of T-N and T-P in TWEs was 3,956.7 μg N L-1 and 50.8 μg P L-1, and the proportion of NO3-N and PO4-P to the total fraction was 72.1% and 40.8%, respectively. Both N and P were high in TWEs, but much higher N than P concentration indicates strong P-limitation. As a consequence, the maximum AGP was determined by PO4-P concentration (r=0.998, p<0.01). Mean AGP value was 15.4 mg dw L-1 among four effluents indicating its eutrophic condition. Due to the establishment of tertiary (advanced T-P) treatment method in the studied plants recently, P concentration was significantly decreased in TWEs compared to the years prior to 2012. However, P concentration seems to be still high enough to cause eutrophication and algal blooms. Therefore, wastewater treatment to P-free level needs to be considered if effluents are directly discharged into the drinking water resources.
5,100원
8.
2017.03 구독 인증기관 무료, 개인회원 유료
Understanding effects of thermal pollution and acidification has long been a concern of aquatic ecologists, but it remains largely unknown in Korea. This study was performed to elucidate the effects of thermal wastewater effluent (TWE) and acid rain on water quality and attached algae in a small mountain stream, the Buso Stream, a tributary located in the Hantan River basin. A total of five study sites were selected in the upstream area including the inflowing point of hot-spring wastewater (HSW), one upstream site (BSU), and three sites below thermal effluent merged into the stream (1 m, 10 m and 300 m for BSD1, BSD2, and BSD3, respectively). Field surveys and laboratory analyses were carried out every month from December 2015 to September 2016. Water temperature ranged 1.7~28.8°C with a mean of 15.0°C among all sites. Due to the effect of thermal effluent, water temperature at HSW site was sustained at high level during the study period from 17.5°C (January) to 28.8°C (September) with a mean of 24.2±3.7°C, which was significantly higher than other sites. Thermal wastewater effluent also brought in high concentration of nutrients (N, P). The effect of TWE was particularly apparent during dry season and low temperature period (December~March). Temperature effect of TWE did not last toward downstream, while nutrient effect seemed to maintain in longer distance. pH ranged 5.1~8.4 with a mean of 6.9 among all sites during the study period. The pH decrease was attributed to seasonal acid rain and snow fall, and their effects was identified by acidophilic diatoms dominated mainly by Eunotia pectinalis and Tabellaria flocculosa during March and August. These findings indicated that water quality and periphyton assemblages in the upstream region of Buso Stream were affected by thermal pollution, eutrophication, and acidification, and their confounding effects were seasonally variable.
5,500원
9.
2017.03 구독 인증기관 무료, 개인회원 유료
Alpine plants with a scarcity of pollinators in harsh environments have been believed to undergo selfing for reproductive assurance; however, contradictory evidence is also available. Snowmelt regimes in alpine areas function to change life history characteristics of alpine plants such as flowering time and duration; yet the effects of snowmelt regimes have never been tested in alpine plants in Korea. This study was conducted to investigate the dichogamy, mating systems, and flowering characteristics of Megaleranthis saniculifolia populations [early and late snowmelt plots (ESP and LSP, respectively)] in a subalpine area of Sobaeksan Mountain in Korea. M. saniculifolia exhibited incomplete protogyny in that despite early maturation of pistils, maturation times of pistils and stamens within flowers were partly overlapped. Control and hand-outcrossing treatments produced significantly higher number of follicles and seeds per flower than autonomous and handselfing treatments. Based on the aggregate fruit set, the auto-fertility index (AI) and self-compatibility index (SI) were 0.33 and 0.50, respectively. Snowmelt occurred 10 days earlier in ESP than in LSP, thereby ESP and LSP showed distinct differences with regard to flower longevity and season, but showing no difference in peak flowering dates. We concluded that M. saniculifolia is an incomplete protogynous and largely outcrossing plant requiring pollinator service. Temporal variation in snowmelt time and subsequent changes in flowering characteristics under climate change may further threaten the population persistence of M. saniculifolia which has already been designated as endangered species in Korea.
4,000원
10.
2017.03 구독 인증기관 무료, 개인회원 유료
We describe characteristics of diversity and distribution of oak forests on the Daegok-cheon gorge of the Southeastern Korean Peninsula, the oldest prehistoric site, in view of a sort of food resources of acorns. The Zürich-Montpellier School’s method was adopted for field investigation on the oak dominant stands. A total of 20 phytosociological relevés composed of 193 taxa were analyzed by syntaxonomy and ecological flora. The Daegok-cheon’s oak forests occupied 36.9% (513,374 m2) of the surveyed area, and its 99% (507,677 m2) was Quercus variabilis and Q. serrata stands. Oak forests of the Daegok-cheon gorge are a kind of regional vegetation type characterizing by the high relative net contribution degree (r-NCD) of Platycarya strobilacea and Sapium japonicum, which are an edaphic type of the xerophilous and thermophilic oak forests. The region of the Daegok-cheon petroglyphs is defined as an ecoregion with rich acorn supply and abundant water resources, and the warmer environment, which attracts prehistoric man.
4,200원
11.
2017.03 구독 인증기관 무료, 개인회원 유료
The identity of toxin producers remains only hypothesis unless there were identified by strain isolation and analytical confirmation of both the cyanotoxin production and the genetic identity of the monoculture. The purposes of this study were to identify a morphologic and phylogenetic classification in Aphanizomenon flos-aquae strains isolated from the Nakdong River and to investigate the potential ability of the strains to produce toxins such as saxitoxin and cylindrospermopsin using target genes. The 16S rRNA and sxtA, sxtI, cyrA, cyrJ genes were analyzed on two strains (DGUC001, DGUC003) isolated from the Nakdong River. Morphological features of the strains were observed a shape of aggregated trichomes in parallel fascicles which can reach up to macroscopic size and a hyaline terminal cell without aerotope. In addition, the 16S rRNA phylogenetic analyses showed that the strains were identified as the same species with high genetic similarity of 98.4% and grouped within a monospecific andsupported cluster I of Aphanizomenon flosaquae selected from GenBank of the NCBI. The cyrA and cyrJ genes encoding for the cylindrospermopsinbiosynthesis were not detected in the present study. The sxtA gene was in detected both the two strains, whereas the sxtI gene which had been suggested as a suitable molecular marker to detect saxitoxin-producing cyanobacteria was not found both the strains. Thus, the two strains isolated from Nakdong River were identified as the same species of Aphanizomenon flos-aquae Ralfs ex Bornet et Flahault 1888, the two strains were confirmed as potential non-producing strains of the saxitoxin and cylindrospermopsin.
4,200원
12.
2017.03 구독 인증기관 무료, 개인회원 유료
In this study, we analyzed the relationship between phytoplankton community and physicochemical factors in 12 lakes located in Jeollanam-do based on the data surveyed from March to November 2014. Totally, 297 species of phytoplankton were identified including 98 Bacillariophyceae, 148 Chlorophyceae, 23 Cyanophyceae and 28 other phytoplankton taxa. The standing crops ranged from 124 to 59,148 cells mL-1 and showed the highest in August with the increase of Cyanophycean cells. The self-organizing map (SOM) was optimized into 9×6 grid and was classified into 5 clusters based on the similarity of environmental factors and phytoplankton indices. The SOM results showed that phytoplankton communities had positive relationship with water temperature, SS, DO, BOD, TP and Chl-a, whereas low relationship with pH, TN, NH3-N, NO3-N, PO4-P and Conductivity. In Pearson’s correlation coefficient, relationship between environmental factors and phytoplankton communities showed similar results with SOM.
4,000원
13.
2017.03 구독 인증기관 무료, 개인회원 유료
Backswamp is the section of a floodplain where deposits of fine silts and clays settle after a flood. In general, the wetland is composed of diverse ecosystems, and is characterized by ecotone. The purpose of this study was to analyze vegetation naturalness and to assess vegetation value by syntaxonomy and synecology of Useupje backswamp at Yeongsan river. As a result, the vegetation was divided into four physyiognomy types and 14 vegetation units depending on the species composition and habitats. The vegetation units confirmed in the study were as follow: Spirodela polyrhiza community as floating plant; Trapa bispinosa var. inuma community and Trapa bispinosa var. inumai-Nelumbo nucifera community as floating-leaved plant; Paspalum distichum community, Persicaria thunbergii community and Phalaridetum arundinaceae as lentic vegetation in the eulittoral zone; Scirpo fluviarilis-Zizanietum latifoliae and Typha angustata community in the emerged zone; Scirpetum tabernaemontani and Phragmitetum australis in the littoral zone; Carex dimorpholepis-Salix subfragilis community ecotone region of upland. According to the study, the vegetation distribution was highly affected by water level and artificial interference. Moreover, the development of vegetation units showed a significant relationship between species composition and habitats. Although vegetation value of Useupje resulted by vegetation naturalness was identified as the grade [III], the ecological value is expected to upward evaluation because of unique vegetation and geographical location.
4,300원
14.
2017.03 구독 인증기관 무료, 개인회원 유료
Physicochemical properties of water quality were analyzed to understand the long-term variations in Lake Youngrang from 1998 to 2015. Nonparametric statistical methods were applied to deduct correlation among water quality parameters and water quality trend. In total observations (N=64), the Secchi depth (SD) transparency showed significant positive correlation with salinity (r=0.458) and highly significant negative correlation with chlorophyll-a (r= - 0.649) for p<0.0001 in two-tailed test of Spearman’s rank correlation. Significant negative correlations of SD were observed with chemical oxygen demand (COD), total phosphorus (TP) and total nitrogen (TN). These correlation patterns were very similar in rainy (N=25) and non-rainy (N= 39) periods too. Chlorophyll-a (Chl-a) had significant correlation with COD. Sen’s slope test was performed along with Mann-Kendall trend test (significance α=0.05, two-tailed) to find water quality trend. Positive trends were observed for SD and salinity with Sen’s slopes 0.012 and 0.385, respectively (p<0.0001). Negative significant trends were observed for total nitrogen (TN) and Chl-a with Sen’s slopes - 0.02 (p<0.0001) and - 0.346 (p=0.0010), respectively. Temperature, COD and phosphorus components had no trends. Carlson’s trophic state index (TSI) for SD, TP and Chl-a were obtained in the ranges of 46~80, 37~82 and 39~82, respectively. Trophic index values suggest that Lake Youngrang was mesoeutrophic to eutrophic and there could be possibility of anoxia during the summer and dominance of blue-green algae. Excess nutrient inputs from external and internal sources were the causes of eutrophication in this lake. The findings of this study would be helpful to recognize water quality variables to manage the water body.
5,100원