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利用倒置“W”九点取样法,对珠三角地区5个城市32个草坪样点进行了季节动态调查。结果表明:春季草坪杂草群落结构以水蜈蚣(Kyllinga brevifolia)+三点金(Desmo-dium triflorum)+狗牙根(Cynodon dactylon)+积雪草(Asiatic pennywort)为主;夏季以水蜈蚣+三点金+香附子(Cyperus rotundus)+伞房花耳草(Hedyotis corymbosa)为主;秋季以水蜈蚣+三点金+伞房花耳草+狗牙根为主;冬季以积雪草+水蜈蚣+天胡荽(Hydrocotylesibthorpoioides)+三点金为主。运用改进的Levins生态位宽度指数和Pianka生态位重叠指数对四季优势杂草生态位进行分析,结果表明,大部分杂草生态位宽度在0.5以下,生态位宽度达到0.50的有水蜈蚣(四季均最高),三点金(秋季)、狗牙根(春季)、酢浆草(Oxalispes-caprae)(春季)。春季优势杂草的生态位重叠指数达到0.60的最多,冬季则最少。生态位重叠指数的最大值出现在夏季,分别是天胡荽和母草(Lindernia crustacea)、白花蛇舌草(Hedyotis diffusa)和瓶尔小草(Ophioglossum vulgatum)之间,可达0.85。
Using the inverted “W ” nine sampling method, the seasonal dynamics of 32 lawn samples in 5 cities in the Pearl River Delta region were investigated. The results showed that the community structure of spring weeds was mainly Kyllinga brevifolia + Desmo-dium triflorum + Cynodon dactylon + Asiatic pennywort. In summer, (Cyperus rotundus + Hedyotis corymbosa); autumn centipede + three gold + Calendula officinalis + bermudagrass; winter Centella asiatica + water centipede + Hydrocotylesibthorpoioides + three gold-based. Based on the improved levins niche breadth index and the Pianka niche overlap index, the dominant niche weeds in the four seasons were analyzed. The results showed that most of weeds had niche breadths below 0.5 and niche breadths up to 0.50 Highest), Three Golden (Autumn), Bermudagrass (Spring), Oxalispes-caprae (Spring). The niche overlap index of dominant weeds in spring reached the highest of 0.60, while the least in winter. The maximum of niche overlap index appeared in summer, which was 0.85 between Lindernia crustacea, Hedyotis diffusa and Ophioglossum vulgatum respectively.