摘要
用 2 m× 2 m的样方调查了湖南茶陵普通野生稻保护区群落 ,绘制了群落优势种水平分布图。选用斑块数量、总斑块面积、平均斑块面积、标准差、变异系数、中值、最大斑块面积、最小斑块面积和优势度等几个描述统计量 ,来刻画斑块大小的分布特征。选取 9个不同生态条件的样地计测了其中 10个主要物种的生态位宽度 ;以群落间接生境梯度代替生态因子梯度 ,计算了其生态位重叠值 ,进行了生态位重叠排序。结果表明 :各物种斑块在群落中呈异质分布 ,物种在群落中发生现实生态位分离 ,这种分离主要是由生境条件特别是生境水位决定的。根据生态位重叠排序可把物种分为 3组 :莼菜 (Brasenia schreberi)、水竹叶 (Murdannia triqeutra)、莲 (N elumbo nucifera)、锐棱荸荠 (Eleocharis acutangula)、水毛花 (Scirpus triangulatus)、慈姑 (Sagittaria trifolia)等分布于 2 0 cm以上的深水位生境 ;普通野生稻 (Oryza rufipogon)、李氏禾 (L eersia hexandra)等分布于 10～ 2 0 cm中水位生境 ;柳叶箬(Isachne globosa)分布于 10 cm以下浅水位生境。排序的结果与物种在群落中的空间分布情况相符合。在普通野生稻的保护实践中 。
Vegetation of the Oryza rufipogon Reserve, in Chaling, Hunan Province was surveyed with 2 m×2 m quadrats and a community horizontal structure map drawn. In total, ninety random sampling quadrats in nine plots under different ecological conditions were surveyed. Several basic descriptive statistical indices were chosen to characterize patch size and spatial distributions. The niche breadth and niche overlap of the ten dominant species were measured on indirect habitat gradients and niche ordination was calculated from the overlap matrix. The results showed that the species distribution was heterogeneous and that niche separation was found among the ten species. The ecological distributions of these species were determined by heterogeneous environmental factors, especially hydrological factors. Ten species occupied a continuum along a water availability gradient, which was divided into 3 groups based on niche ordination: Brasenia schreberi, Murdannia triquetra, Nelumbo nucifera, Eleocharis acutangula, Scirpus triangulatus, and Sagittaria trifolia were found in water deeper than 20 cm. O. rufipogon and Leersia hexandra occurred at a depth of 10 cm to 20 cm. Isachne globosa was found at a depth of less than 10 cm. The maintenance of the suitable habitat, especially the suitable water level, is essential for the conservation of O. rufipogon.
出处
《植物生态学报》
CAS
CSCD
北大核心
2001年第1期65-70,T002,共7页
Chinese Journal of Plant Ecology
基金
国家自然科学基金资助项目 !(396 0 0 0 15 )
