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研究了云勇林场的杉木林在刚皆伐(2004年10月)和皆伐半年后(2005年4月)的土壤养分的变化状况,对杉木林刚皆伐和皆伐半年后,从上到下5个坡位的3个土层(0～20cm、20～40cm和40～60cm)的土壤的pH、有机质、水解性氮、速效磷和速效钾含量进行测定。结果表明,皆伐半年后大多数坡位的各土层土壤pH均低于刚皆伐的相应土层,5个坡位各土层的土壤有机质含量均高于刚皆伐的相应土层,土壤水解性氮含量高于或接近于刚皆伐的相应土层。大多数坡位皆伐半年后的土壤速效磷含量明显低于刚皆伐的相应土层,大多数坡位皆伐半年后各土层的土壤速效钾含量多高于刚皆伐的相应土层。
The changes of soil nutrients of Cunninghamia lanceolata forest in Yunyong forest farm were studied after just clear cutting (October 2004) and six months after clear cutting (April 2005) The soil pH, organic matter, hydrolyzable nitrogen, available phosphorus and available potassium contents in the three soil layers (0 ~ 20cm, 20 ~ 40cm and 40 ~ 60cm) in the next five slope positions were measured. The results showed that after six years of clear cutting, the soil pH values of all soil layers in most slope positions were lower than that of the corresponding layers just after cutting. The soil organic matter content in each of the five slope positions was higher than that of the corresponding layer of just clear cutting, Soil hydrolyzable nitrogen content is higher or close to that of freshly cut corresponding soil. After six months of clear cutting, the content of available phosphorus in the soil of most slopes was significantly lower than that of the corresponding layer of just clear cut. After most of the slopes were polluted for six months, the contents of available potassium in soil were much higher than those of the corresponding layers .