【摘要】 草原不同时间火烧后，一些特征发生了明显的不同变化．秋烧后土壤含水量比未烧和春烧低，春季不同时间火烧后的差别不大．秋烧地产量及群落组成和物种多样性都明显比未烧地和春烧地低，但一年生植物种类增多．春季不同时间火烧后产量变化差异不显著，但晚春火烧后顶芽植物种类减少．不同生活型的种类对同一次火烧的反应不同，这不仅表现在个体生长方面，也表现在种群产量方面．更多还原

【Abstract】 After firing in different season, some characters of Songnen grassland varied obviously. As compared with unfired or fired in Spring, the soil water content was lowered after fired in Autumn, but little difference was found after fired at different periods of Spring. The grass yield, population composition and species diversity after fired in Autumn were significantly lower than those after unfired or fired in Spring, but the species of annual plant increased. No significance difference was found in grass yield after fired at different periods of Spring, but top bud species decreased after fired in late Spring. Different life form species had different response on the same firing, not only in their individual growth, but also in their yields.更多还原