• Journal of Ecology and Environment
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• 제41권8호
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• pp.202-212
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• 2017

Background: To reveal establishment strategy of Sparganium erectum, we tried to find realized niche of adults through field survey and effects of water level on the establishment process through mesocosm experiments. Results: In the field survey, the height and coverage of community living in deeper water were greater than those of community living in shallow water. There was no statistically significant difference (p > 0.05) in the means of water and soil properties between the two communities. In mesocosm experiments, we found no correlation between water levels and germination rates, but S. erectum seedlings have characteristics of post germination seedling buoyancy when S. erectum seeds germinated in inundation conditions. Shoot height, total leaf length, and survival rates of sinking seedlings in shallow water levels at -5, 0, and 5 cm were higher than those in deeper water levels at 10 and 20 cm. Floating seedlings established in water levels of 3 and 6 cm only. The seedlings could live up to 6 weeks in floating state but died if they were unable to establish. Conclusions: The water level around adult S. erectum communities in the field were different from the water level at which S. erectum seedlings can survive in the mesocosm experiments. The findings provided not only understanding of S. erectum habitat characteristics but also evidence to connect historical links between the early seedlings stage and adult habitat conditions. We suggested the logical establishment strategy of S. erectum based on the data.

• Journal of Ecology and Environment
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• 제38권3호
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• pp.375-381
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• 2015

We investigated the influence of summer rainfall on Pectinatella magnifica colonies in lotic ecosystems. Of the examined substrate materials, branches and aquatic macrophytes supported more colonies of P. magnifica than that by stones or artificial materials. The influence of rainfall on P. magnifica colonies differed in accordance with the type of substrate material at each study site. In the Geum River, little difference was noted in the number of P. magnifica colonies on branches before ($mean{\pm}SE$, $24{\pm}7.3$ individuals) and after rainfall ($20{\pm}8.4$ ind.); other substrate types supported fewer colonies of P. magnifica after rainfall. In contrast, in the Miryang River, rainfall had minimal effect on the number of P. magnifica colonies supported by macrophytes ($13{\pm}3.8$ and $12{\pm}4.3$ ind., respectively). Artificial material was more abundant in the Banbyeon Stream where it was able to support more colonies of P. magnifica. We found that the structure of different substrates sustains P. magnifica following rainfall. In the Miryang River, free-floating and submerged plants with a relatively heterogeneous substrate surface were the dominant macrophytes, whereas in the Geum River, simple macrophytes (i.e., emergent plants) were dominant. Therefore, we conclude that the substrate type on which P. magnifica grows plays an important role in resisting physical disturbances such as rainfall.

• 생태와환경
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• 제47권1호
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• pp.62-69
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• 2014

Standing crop distribution of aquatic plants in the West Nakdong River and riparian wetlands in the Nakdong River were surveyed in May, July and September, 2010. Total 25 aquatic macrophyte species (submerged: 9, leaf-floating: 3, free-floating: 5, emergent: 8) were observed during the survey periods. Distribution area of aquatic plants and proportion of submerged communities were highest in Garakchi-deung ($212,032m^2$, 72.7%). The distribution area of aquatic plants was highest in Phragmites australis community ($421,584m^2$), followed by Hydrilla verticillata-Vallisneria natans community ($181,511m^2$), Potamogeton wrightii-Vallisneria natans community ($61,604m^2$), and Hydrocharis dubia community ($49,709m^2$). Garakch-ideung (212,032 kg) also had the highest aquatic plant production, followed by Suanchi-deung (15,546 kg), Daedong (5,813 kg), Dunchi-do (3,963 kg), Maekdo (1,463 kg), Yeommak (571 kg), Jungsa-do (530 kg), and Shinan (300 kg). Average standing crop of the study area were $147.8{\pm}20.8g\;DW{\cdot}m^{-2}$ in 1988, $96.1{\pm}20.0g\;DW{\cdot}m^{-2}$ in 2000, and $172.6{\pm}76.1g\;DW{\cdot}m^{-2}$ in 2010. For a sustainable management of river habitat and food source, aquatic plant should concurrently be surveyed with river environmental variables (i.e. sediment, nutrient, flow).

• 한국물환경학회지
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• 제24권6호
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• pp.709-717
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• 2008

The field scale experiment which is constructed with four sets (0.88 ha for each set) of wetland (0.8 ha) and pond (0.08 ha) systems was performed to examine the effect of plant coverage on the constructed wetland performance and to recommend the optimum development and management of macrophyte communities. After six growing seasons of wetlands, plant coverage was about 100%. And the concentration of DO showed low value (1.0~5.4 mg/L). This is caused by a blighted plant consumed dissolved oxygen with decay in water column. As the result, water column went to be anaerobic conditions and T-N removal rate are 58~67%. Dead vegetation increased nitrogen removal during winter because it is a source of organic carbon which is an essential parameter in denitrification. However, wetland released phosphorus caused by a blighted plant and accumulation, the removal rate of phosphorus might be decreased. To rise of DO concentration, the three open-waters were constructed in cell 3 and 4. Cell 3 has two open-waters (width 10 m, depth 1.8 m) and cell 4 has one open-water (width 20 m, depth 1.8 m). As the result, DO concentration and treatment efficiency of nutrient and BOD were improved. In case that constructed wetland is operated for a long time, physical circulation structure such as open water help continuous circulation of aerobic and anaerobic conditions. Through the constructed open-water, treatment efficiency of phosphorus and nitrogen in wetland could be improved effectively.

• Environmental Engineering Research
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• 제11권3호
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• pp.134-142
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• 2006

The treatment of high-strength swine wastewater by anaerobic digestion combined with an aquatic plant system was investigated. Anaerobic digestion of swine wastewater gave volatile solids (VS) removal efficiencies of 43.3%, 52.1% and 54.5% for hydraulic retention times (HRTs) of 20, 30, 40 days, respectively. The removal efficiencies of VS, total chemical oxygen demand (TCOD) and soluble chemical oxygen demand (SCOD) decreased with increasing VS volumetric loading rate (VLR). Higher organic removal efficiency was observed at longer HRTs for the same VS volumetric loading rate. As VS volumetric loading rate increased, biogas production increased and the methane content of the biogas decreased. Experiments using duckweed (Lemna species) as an aquatic macrophyte gave the following results. In the case of nitrogen, removal efficiency was above 60% and effluent concentration was below 10.0 mg/L when the influent ammonia-N loading was about $1.0\;g/m^2/day$. In the case of phosphorus, removal efficiency was above 55% and effluent concentration was below 2.0 mg/L when the influent $PO_4$-P loading was about $0.15\;g/m^2/day$. In addition, crude protein and phosphorus content of duckweed biomass increased from 15.6% to 41.6% and from 0.8% to 1.6%, respectively, as the influent nutrient concentration increased. The treatment of high-strength swine wastewater by anaerobic digestion combined with an aquatic plant system offers good performance in terms of organics and nutrient removal for relatively low operation and maintenance costs. The results indicate that under appropriate operational conditions, the effluent quality is within the limits set by Korean discharge criteria.

• Journal of Ecology and Environment
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• 제30권3호
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• pp.231-236
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• 2007

This study examined the decomposition of blades and culms of aquatic emergent plant species, Zizania latifolia, Phragmites communis and Typha angustata, and changes in nutrient contents during decomposition. Z. latifolia, P. communis and T. angustata were the most frequently occurring species in Lake Paldang of Han River, Korea. Experiments were carried out from July 27 to December 14, 2005 in Lake Paldang using the litter bag method. The remaining masses of blade litter of each species at the end of experimental period were 21.2% of initial dry weight in Z. latifolia, 32.5% in P. communis, and 44.7% in T. angustata. In addition, the remaining mass of culm was 22.6% of initial dry mass in Z. latifolia, 56.4% in P. communis, and 38.1% in T. angustata. During the litter decomposition period, P, K, Na, and Mg concentration decreased rapidly within 10 days, but Ca and Mg concentration declined slowly. K contents remained below 10% of initial values in all litter samples retrieved during decomposition, whereas Ca and Mg concentration remained above 40% and 50% during decomposition in all three species. Na, P and Mn contents in litter varied among species and plant parts. P concentration in culms of P. communis remained at about 60% of initial concentration throughout the study, but the remaining P content in culms of Z. latifolia was only 10% of the original value at the end of the study period. The Mn concentration in blades of P. communis increased about 15-fold relative to the initial content by the end of experiment.

• 한국환경생태학회지
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• 제24권6호
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• pp.772-780
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• 2010

왕우렁이(Pomacea canaliculata)는 1983년에 식용으로 일본에서 한국으로 도입된 외래종으로서, 농업에서 벼의 직파 논의 잠재적인 해충이다. 본 연구에서는 해충화되고 있는 왕우렁이의 생육특성과 충남 및 전북지역에서의 월동생태를 구명하였고, 또한 농수로에서 수생식물과 수질에 미치는 영향을 조사하였다. 자연수로에서 조사결과를 보면 왕우렁이가 높은 밀도로 서식하는 수로에서는 왕우렁이가 서식하지 않을 경우에 많았던 검정말, 붕어마름, 개구리밥, 좀개구리밥 등의 수생식물들이 발견되지 않았다. 폐쇄형 인공수조실험에서는 왕우렁이가 수생식물들을 먹이로 섭식하면서 이들 식물들을 제거하고, 수질 지표인 EC, COD, T-N 및 T-P을 높이는 것으로 나타났다.

• 한국습지학회지
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• 제11권1호
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• pp.65-73
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• 2009

황구지천과 청미천의 본류와 폐천에서 하도형태, 식물상 및 식생분포 특성을 분석하였다. 항공사진과 옛 지형도를 분석한 결과, 폐천은 제방축조에 의해 사행하도가 단절되어 형성된 것으로 나타났다. 전체 식물종수와 귀화식물 백분율은 본류가 폐천에 비해 높았다. 두 폐천에서 수생, 습생식물 종수의 백분율은 각각의 본류에서 보다 높았다. 주성분분석결과 폐천과 본류 사이의 식물상 구조는 황구지천이 청미천에 비해 비교적 유사하게 나타났다. 두 폐천에서 수생, 습생 식물 분포 면적비율은 각각의 본류에 비해 높았다. 두 폐천에서 우점식물은 정수식물인 줄이었다. 따라서 폐천의 식물상과 식생분포는 습생, 정수 생태계의 특성을 나타내었으며 경관수준에서 다양성을 제공하였다.

• Applied Microscopy
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• 제34권2호
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• pp.103-111
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• 2004

수생식물 개구리밥(Spirodela polyrhiza)의 식물체 발달 과정에서 나타나는 미생물과의 상호관계를 주사전자현미경 및 세포학적으로 추적하여 연구하였다. 개구리밥은 부유성 식물로 분화 발달 초기부터 잠수부위에 여러 종류의 박테리아, 남조류, 규조류 등이 서식하였다. 미분화된 어린 식물체에는 성숙 발달한 식물체에 비해 미생물들이 낮은 빈도로 출현하였고, 성숙한 식물체에서는 특히 엽상체 하피에 가장 많은 미생물들이 서식하였으며, 그 다음으로는 점액성 물질이 층을 이루는 근관에 많이 관찰되었다. 반면, 신장 발달 중의 뿌리에는 일반적인 분포를 보였으며, 상피에는 미생물이 거의 분포하지 않는 양상을 보였다. 이들 미생물이 개구리밥 조직 내에 침입하여 식물체에 어떠한 영향을 미치는가를 조사하기 위해 엽상체, 연결사, 뿌리, 근관, 무성생식낭 등의 구조를 세포학적으로 추적한 결과, 어느 부위에서도 조직 내로 미생물이 침입하여 세포를 괴사시키거나 감염시키는 일은 거의 관찰되지 않았다. 그러므로, 개구리밥 식물체의 발달과정에 있어 미생물들은 어떠한 해를 주지 않는 것으로 추정된다. 이후 개구리밥에 서식하는 미생물의 질소고정치를 측정하여 그 기능을 식물체의 세포학적 측면과 접목시켜 연구하면 개구리밥과 미생물과의 상호관계가 공생적인지를 더 확실하게 밝힐 수 있을 것이다.

• 환경생물
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• 제29권4호
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• pp.296-304
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• 2011

2010년 2월부터 12월까지 상수원 호소인 가창호에 대한 수질 및 생물상을 조사하였다. 가창호 유역내 총 BOD 발생부하량은 생활계가 53%로 가장 많이 차지하였으며 토지계(27%), 축산계(16%) 순으로 나타났다. 가창호 유역내 총 TN, TP 발생부하량은 토지계가 각각 59%, 42%로 가장 많이 차지하였다. 가창호 유역내 총 BOD 배출부하량은 토지계가 61%의 높은 비율을 나타내었고 생활계(24%), 산업계(11%) 순으로 나타났다. TN, TP 배출 부하량은 모두 차지하는 비율이 75 이상으로 토지계가 높게 나타났다. 가창호 수질의 경우, 유기물 오염도는 COD의 연간평균값이 3.5 mg $L^{-1}$로 호소환경기준으로 약간 좋음(II)을 나타내었으며, 부영양화도 지수로는 연평균 중영양 상태를 보여주었다. 조류발생정도는 3월과 9월에 다른 달에 비해 상대적으로 높은 값을 나타내었으나, 호소환경기준으로 좋음(Ib)을 나타내었다. 식물플랑크톤은 연중 규조류가 대부분 우점하였으나, 4월과 7월에 기타 편모조류가 우점하여 출현하였다. 그리고 8월에서부터 11월까지는 $Cyclotella$ 속이 우점하여 출현하였다. 동물플랑크톤의 경우에는 소형 윤충류의 출현 종수가 다양한 것으로 나타났다. 2월에는 윤충류인 $Conochilus$ sp., 3월~7월에는 윤충류인 $Keratella$ $cochlearis$가 모두 우점하였고 특히 4월에는 윤충류가 49.8%의 높은 상대풍부도를 나타내었다. 11월에 요각류인 $Cyclops$ sp.가 우점한 것을 제외하면 9월~12월 동안 윤충류인 $Polyarthra$ $vulgaris$가 우점하였고 8월에는 요각류인 Nauplii가 우점하였다. 수생식물은 가창호 수변을 따라 다양한 군락이 나타났다. 주로 선버들군락과 물억새군락이 넓게 형성되어 있으며 도로 인접지역은 칡 피복이 심하고 북쪽 다리 상류 쪽에는 달뿌리풀군락과 왕버들, 갈풀, 여뀌군락이 소규모로 분포하였다. 저서성대형무척추동물의 섭식기능군 (FFG)을 조사한 결과, 조사지점 전체에서 GC (Gathering-Collector)와 SH(Shredder)가 조사되었으며, GC 분류군이 가장 높은 종 및 개체수 비율을 차지하는 것으로 조사되었다. 어류는 총 7종이 출현하였으며 잉어과 어류가 5종으로 가장 많이 출현하였다. 참갈겨니, 꺽지와 같이 물이 맑고 바위와 자갈이 많은 하천 중 상류에 서식하는 어종이 일부 채집되었는데 가창호의 경우 하천의 상류지점에 위치하고 낮은 수온을 유지하여 이들 어류가 서식 가능한 것으로 판단된다.