关键词: 紫椴, 水曲柳, 人工林, 物候, 霜冻, 控制

Abstract: This paper describes microbial groups in different soil types of reservoir area in Yantse gorges. The total amount of microbes is related to the soil structure and fertility, especially in black limestone soil which contains more organic matter. The ecological distribution of various microbial groups in different soil types is similar. The amount of heterotrophic bacteria is the highest, that of actinomyces and fungi is lesser, and that of nitrifying bacteria is the lowest, The amount of microbes in the upper layer of soil is more than that in bottom layer.

Key words: Tilia amurensis, Fraxinus mandshurica, Plantation, Pehenophase, Late frost control