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锦屏县能出现八年杉的决定因素,有以下几点:(1)土壤好:杉木快速丰产与土壤有关,调查过的五块丰产林,都是黄泡土,上面的黑土层也厚,腐植质多,表层土褐色。这五块都是一耕地(与农业上的休闲地一样,一耕土的土壤结构好,腐植质厚,较疏松)。栽杉前是杂木林,土壤结构好。(2)林木生长均匀:决定林子长得整齐和均匀的因子一是种子苗木选得好,二是造林成活率一定要
Jinping County, there are eight deciduous factors, the following: (1) the soil is good: fir fast yield and soil-related survey of five high-yield forests, are yellow soils, the above black soil layer is also thick , Humus and more, brown soil surface. All five are cultivated land (as with fallow land in agriculture, the structure of soil is good in arable land, humus is thick and loose). Before planting fir is a mixed wood, soil structure is good. (2) Uniform growth of trees: determine the factors that make the forest grow neatly and evenly. First, seedling selection is good. Second, afforestation survival rate must be