渝西地区火烧迹地早期恢复植被特征研究

Study on the Vegetation Characteristics at Early Recovery Stage in the Burned Areas in Western Chongqing

通过对渝西地区黄瓜山火烧1年后的迹地以及未火烧林地的群落学调查,研究了不同强度火干扰后群落早期恢复植被特征。结果表明:与未火烧林地相比,火烧迹地内阳生木本植物幼苗物种种数增加,更新苗主要以杉木(Cunninghamia lanceolata)、桉树(Eucalyp-tus robusta)、白栎(Quercus fabric)、油茶(Camellia oleifera)等萌生枝为主。不同强度火干扰迹地具萌枝的优势乔木树种及所有树种的密度大小均表现出中度火烧迹地显著高于未烧林地和重度火烧迹地(P<0.05);未经火烧林地物种多样性丰富,火烧以后在短时期内降低了群落的多样性及均匀性水平。中度火烧迹地的草本植物盖度明显大于未烧林地(P<0.05),蕨(Pteridium aquilinum)和小白酒(Conyzacanadensis)成为草本优势种。

Based on field investigation, the early recovery vegetation characteristics in the burned areas in Huanggua Mountain of western Chongqing were studied. The results showed that compared with the unburned field, species number of woody heliophilous plant seedlings in- creased in the burned field, mainly including seedling sprouts of Cunninghamia lanceolata, Eucalyptus robusta, Quercus fabric and Camellia oleifera. Densities of dominant species with seedling sprouts and all species in the fields of moderately burned were higher than those in severely burned and unburned field （P 〈 0.05 ）. After the fire, the species diversity indices and Pielou evenness index of the shrub layer and herb layer all decreased in a short period, the coverage of herbaceous plants obviously increased in the burned field of middle severity. Pteridium aquilinum and Conyza canadensishave became the dominant species of herbs.