Competition between Bulrush(Scirpus juncoides Roxb.) and Rice under the Different Fertilizer, Water Depth, and Light Restriction

비료성분(肥料成分)·수심(水深) 및 광제한(光制限)에 따른 올챙고랭이(Scirpus juncoides Roxb.)의 종간경합(種間競合)에 관한 연구(硏究)

The plant height, shoot numbers and dry matter weight in both bulrush and rice were increased by high level of nitrogen fertilizer and especially the dry matter weights in both species were sharply increased by high level of nitrogen fertilizer. The plant height, dry matter weight in rice, and shoot, and dry matter weight in bulrush were increased by high level of phosphorus fertilizer. The deficient symptom disappeared with change of low level into high level phosphorus in rice. The plant height, dry matter weight and shoot numbers in rice and bulrush were increased by high level of potassium fertilizer. In the inter-specific competition in bulrush according to various water levels, the plant heights in both species elongated longer with deep water levels, and the plant height and dry matter weight in bulrush were more sharply decreased than in rice by deep water levels. The shoot numbers and dry matter weight were critically dropped above 6-8 cm water level. In case of the shoot numbers for light source, in both species were more decreased in mixed culture than each monoculture. The exserted shoot length and weight in bulrush were larger than those in rice. The shaded shoot dry weight was more decreased in mixed culture than in each monoculture, and the decrement was larger in bulrush than in rice.

1. 비료성분별(肥料成分別)의 올챙고랭이 종간경합특성(種間競合特性) 질소시비량(窒素施肥量) 증가(增加)로 두 식물종(植物種) 모두 초장(草長), 경수(莖數), 건물중(乾物重)이 증대(增大)되었으나 초장(草長)과 경수증가(莖數增加)는 올챙고랭이보다 벼가 민감하였다. 또한 가리시비량(加里施用量) 증가(增加)로 벼는 전반적인 생장(生長)이 촉진(促進)되었으며, 올챙고랭이는 경수(莖數)와 건물중(乾物重) 형성(形成)에서 효과적(效果的)이었다. 2. 수심차이(水深差異)에 따른 올챙고랭이의 종간경합특성(種間競合特性) 두 식물(植物) 모두 밭 조건(條件)보다는 담수심(湛水深)이 깊어질수록 초장(草長)이 커졌으나, 경수(莖數)(분얼수)와 건물중(乾物重)에 있어서는 올챙고랭이의 경우 밭 조건(條件)일수록 벼에 대한 우위성(優位性)이 있었으나 수심(水深) 6~8cm 이상에서는 두 식물종(植物種) 모두 분얼수 및 건물중(乾物重)이 심하게 감소(減少)하였다. 3. 광제한(光制限)에 따른 올챙고랭이의 종간경합특성(種間競合特性) 광제한(光制限)으로 단식(單植)보다 혼식(混植)에서 두 식물(植物) 모두 경수분화(莖數分化)가 비슷한 비율(比率)로 감소(減少)되는 경향(傾向)이었으나 채광역(採光域)의 경엽장(莖葉長)과 경엽중(莖葉重)의 증가폭(增加幅)은 벼보다 올챙고랭이가 컸다. 차광역(遮光域)의 지하부증(地下部重)은 벼보다 올챙고랭이가 단식(單植)보다 혼식(混植)에서 현저히 감소(減少)하는 경향(傾向)이었다.