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一、立地选择杨树是落叶阔叶树中的速生树种,在土层深厚、疏松、肥沃、湿润、排水良好的冲积土上生长最好,我省杨树造林地主要在平原地区和山区沟谷地带,造林地应具备以下条件:1.土层深厚,有效土层厚度大于10m(包括沙土地)。2.土壤质地较轻。黑杨派树种(如欧美杨和美洲黑杨品种)以轻壤土和中壤土最好,沙壤土和沙土次之;白杨派树种(如毛白杨)可在较重土壤上生长。3.地下水位适宜。杨树生长适宜的地下水位应在1.5m 左右,生长期内地下水位应在1m 以下,不低于2.5～3m。4.土壤养分含量较高。最低要求:有机质含量大于0.4%,含氮大于0.03%。
First, site selection Poplar deciduous broad-leaved tree species in the fast, deep, loose, fertile, moist, well drained alluvium on the best growth, the province’s poplar mainly in the plains and mountainous areas of the valley, Afforestation should have the following conditions: 1 deep soil, effective soil thickness greater than 10m (including sandy land). 2. Soil texture is light. Populus and poplar trees (such as Populus euphratica and Populus tomentosa) are best in light loam and middle loam, followed by sandy loam and sand; Poplar trees (such as Populus tomentosa) can grow on heavier soils. 3. Suitable groundwater level. Poplar suitable groundwater level should be about 1.5m, during the growth stage groundwater level should be less than 1m, not less than 2.5 ~ 3m. 4. Higher soil nutrient content. Minimum requirements: organic matter content is greater than 0.4%, nitrogen is greater than 0.03%.