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本文通过对干旱河谷封山育林区域与未封山育林区造林苗木生长状况和灌草群落特征对比,开展封山育林对干旱河谷区植被恢复成效研究。研究结果表明:在相同坡向和海拔梯度上,封山育林区造林苗木平均保存率和树高净生长量均极显著性高于未封山育林区,其差值变化幅度分别为21%(阴坡Ⅰ)~31%(阴坡Ⅲ)和42.7%(阳坡Ⅰ)~59.7%(阳坡Ⅱ);灌草平均盖度和高也表现为封山育林区高于未封山育林区,灌木和草本平均盖度差值变化幅度1.1%(阳坡Ⅰ)~26.7%(阳坡Ⅱ)和2.2%(阳坡Ⅰ)~18.5%(阳坡Ⅱ)之间;灌木和草本平均高度差值变化幅度8.2%(阳坡Ⅰ)~53.5%(阴坡Ⅲ)之间和17.9%(阴坡Ⅲ)~28.9%(阴坡Ⅱ)之间。
In this paper, by comparing the growth status of shrub-seedlings and the characteristics of shrub-grass plantations in the closed-hill afforestation area and unsealed hillside afforestation area in dry valley, the effect of afforestation by closing hillsides on vegetation restoration in the arid valley area was studied. The results showed that the average preservation rate and tree height net growth rate of afforestation seedlings in the closed hillside afforestation area were significantly higher than that in the unclosed hillside afforestation area at the same slope and altitudinal gradient, and the differences were 21% (shady Ⅰ) ~ 31% (shady slope Ⅲ) and 42.7% (sunny slope Ⅰ) ~ 59.7% (sunny slope Ⅱ). The average coverage of shrubs and shrubs was also higher The variation range of the average height difference between shrub and herb was 8.2% (positive slope Ⅰ) ~ 26.7% (sunny slope Ⅱ) and 2.2% (sunny slope Ⅰ) ~ 18.5% (sunny slope Ⅱ) Slope Ⅰ) to 53.5% (shady slope Ⅲ) and between 17.9% (shady slope Ⅲ) to 28.9% (shady slope Ⅱ).