毛乌素沙地飞播造林植被恢复特征及土壤性质变化

摘要

As an important mean of desertification vegetation recovery, aerial seeding afforestation has been widely used in the desertification control project. The changes of vegetation characteristics and soil properties in Mu Us Sandy Land by aerial seeding afforestation in Inner Mongolia Autonomous Region were studied. The results reveal that in the process of vegetation restoration, the vegetation cover, species density, aboveground biomass and underground biomass increased significantly;In the first 5 years of vegetation restoration, the annual growth of vegetation cover and species density were 5.87% and 8.20 trees/m2, the aboveground biomass and underground biomass of vegetation increased to 295.33 g/m2 and 579.00 g/m2 respectively;After 17 years revegetation, the aboveground biomass and underground biomass of vegetation reached 963.83 g/m2 and 1741.67 g/m2 respectively;At the same time, the sand grain content of 0~10 cm soil dropped from 94.90%to 57.95%, the content of coarse silt increased from 3.33%to 29.22%and physical clay increased from 1.77%to 12.83%;Besides, the soil bulk density dropped from 1.48 g/cm3 to 1.44 g/cm3;The organic matter, total N, hydrolysable N, available P and available K increased by 700.54%, 254.55%, 248.33%, 234.84%and 203.30%respectively;Indeed, the soil physicochemical property improved greatly, especially in the surface soil. The correlation analysis shows that the vegetation cover, species density, aboveground biomass and underground biomass had significant positive correlation with the soil organic matter, total N, hydrolysable N, available P, available P, coarse silt and physical clay (p<0.05) in 0~20 cm, but the significant negative correlation with the soil bulk density and sand (p < 0.05 ). The findings indicate that there was an interaction between vegetation and soil in the process of vegetation restoration.%飞播造林作为沙漠化地区植被恢复的重要手段，在沙漠化治理工程中得到广泛运用。以内蒙古自治区毛乌素沙地飞播造林地为对象，研究了不同植被恢复年限样地植被恢复特征及土壤理化性质变化。结果表明：植被恢复过程中，植被盖度、植被密度、地上生物量和地下生物量都有了明显的增长，植被恢复前5 a，植被盖度年增长为5.87%，物种密度年平均增长量为8.20株/m2，植被地上、地下部分生物量分别达到295.33 g/m2、579.00 g/m2。经过17 a的植被恢复，植被地上、地下部分生物量分别达到963.83 g/m2、1741.67 g/m2；0～10 cm土壤的砂粒含量由94.90%下降到57.95%，粗粉粒和物理性黏粒含量分别由3.33%和1.77%增加到29.22%和12.83%，土壤容重由1.48 g/cm3下降到1.33 g/cm3；0～10 cm土壤有机质、全氮、水解氮、有效磷和速效钾分别增加了700.54%、254.55%、248.33%、234.84%和203.30%，土壤理化性质得到了明显改善，特别是表层土壤更为明显。植被盖度、密度、地上生物量、地下生物量和0～20 cm土壤有机质、全氮、水解氮、有效磷、速效钾、粗粉粒、物理性黏粒呈线性正相关（p＜0.05），和土壤容重、砂粒呈线性负相关（p＜0.05），表明在植被恢复过程中，植被和土壤有着相互促进的作用。