초록
도시하천 제방사면의 다년생 초본류 군락 형성 연구를 위해 2009년 4월 중순 물억새, 억새, 띠, 수크령, 새를 식재하였다. 새는 분주를 식재하였고, 나머지 초종은 이년생 포트를 식재하였다. 식재 후 3년간 매년 2회의 잡초 제거를 통해 2011년 군락이 형성되었다. 2012년과 2013년은 잡초를 제거하지 않고 실험초종이 군락을 유지하는지 관찰하였다. 잡초를 제거한 2011년과 잡초를 제거하지 않은 2012년간, 잡초를 제거하지 않은 2012년과 2013년간 줄기수와 초장에 차이가 있는지 5월, 7월 9월의 줄기수와 초장을 활용하여 유의수준 0.05에서 t-검정을 하였다. 실험초종 모두 2012년의 줄기수가 2011년보다 적어(p<0.001) 잡초의 피해를 입었다. 억새, 띠, 수크령, 새의 초장은 2012년이 2011년보다 작아 잡초의 피해가 나타났다. 물억새의 초장은 5월과 7월에 차이를 보여 잡초의 피해를 입었으나 (p<0.001), 9월에는 차이가 없어(p=0.098) 피해를 입지 않았다. 2012년과 2013년간t-검정 결과, 새를 제외한 나머지 초종은 줄기수와 초장에 차이가 없었다(p>0.05). 이들 초종은 군락이 형성된 후 잡초의 피해 없이 군락이 유지되었다. 새는 줄기수와 초장 모두 차이를 보여 잡초의 피해가 컸다. 물억새, 억새, 띠, 수크령은 군락 형성 후 잡초 제거 없이 군락이 유지되었으나, 새는 잡초의 피해가 커 군락 유지가 어려웠다. 군락 형성 및 유지, 하천경관 개선, 제방사면 보호의 관점에서 물억새, 억새, 띠가 적합한 것으로 나타났다.
In order to investigate community formation ability, herbaceous perennials such as Miscanthus sacchariflorus Bentham, Miscanthus sinensis var. purpurascens Rendle, Imperata cylindrica Linne, Pennisetum alopecuroides (L.) Spreng. and Arundinella hirta Tanaka were planted in April 2009 at the levee slope of Gwangju Stream in South Korea. Miscanthus sacchariflorus Bentham, Miscanthus sinensis var. purpurascens Rendle, Imperata cylindrica Linne and Pennisetum alopecuroides (L.) Spreng. which grew in pots for two years and divided rhizomes of Arundinella hirta Tanaka gathered from fields were employed. Weeds growing on the experiment sites were removed twice a year until 2011 when the plant species were formed into community. Weeds were not eradicated during 2012 and 2013 to observe community sustainability of the species. T-tests on stem numbers and heights in May, July and September were conducted between 2011 and 2012, and between 2012 and 2013. Stem numbers of the five species in 2012 were significantly reduced(p<0.001) compared with those in 2011, which were attributed to weed growth in 2012. Heights of Miscanthus sinensis var. purpurascens Rendle, Imperata cylindrica Linne, Pennisetum alopecuroides (L.) Spreng. and Arundinella hirta Tanaka in 2012 were significantly lower than those in 2011(p<0.001), which resulted from weed invasion. Heights of Miscanthus sacchariflorus Bentham in May and July 2012 were significantly decreased compared with those in 2011(p<0.001), however, heights of Miscanthus sacchariflorus Bentham in September 2012 were almost the same as those in 2011(p>0.05). Miscanthus sacchariflorus Bentham was able to compete against weeds in September 2012. Stem numbers and heights of Miscanthus sacchariflorus Bentham, Miscanthus sinensis var. purpurascens Rendle, Imperata cylindrica Linne and Pennisetum alopecuroides (L.) Spreng. in 2013 were similar to those in 2012(p>0.05). However, stem numbers and heights of Arundinella hirta Tanaka in 2013 were significantly decreased compared with those in 2012(p<0.001). After community formation, Miscanthus sacchariflorus Bentham, Miscanthus sinensis var. purpurascens Rendle, Imperata cylindrica Linne and Pennisetum alopecuroides (L.) Spreng. were able to maintain its community without weed removal. However, Arundinella hirta Tanaka was unable to establish its community due to the weed growth. Miscanthus sacchariflorus Bentham, Miscanthus sinensis var. purpurascens Rendle, Imperata cylindrica Linne are more suitable to stream levee slope environment in terms of community formation and maintenance, stream landscape enhancement and slope erosion control.