浙江省丽水不同前茬杉木林土壤性质与林木生长

重点论述浙江省丽水地区花岗岩立地条件下不同前茬的杉木林的土壤性质变化及其与林木生长的关系。研究结果表明 ,前茬是马尾松、阔叶树和灌丛的杉木生长量均比连茬杉木林高 ,树龄 5a之后 ,差异十分显著。在不同前茬的杉木林土壤中细菌、真菌和固氮菌数量以连茬杉木林土壤最低 ,只是放线菌数量并不低 ;和其他不同前茬的杉木林土壤相比 ,连茬杉木林土壤中转化酶活性和脲酶活性较低 ,连茬杉木林土壤速效磷含量明显低于其他不同前茬杉木林样地土壤 ,Ca2 、Mg2 含量也有类似的规律。逐步回归分析结果显示 ,不同前茬杉木林土壤转化酶活性、速效氮、速效钾及Mg2 含量与林木生长呈正相关 ,有机质、脲酶及过氧化氢酶活性与林木生长呈负相关

SOIL PROPERTIES AND FOREST GROWTH IN CHINESE FIR FOREST SOILS DIFFERENT IN PRECEDING VEGETATION IN LISHUI OF ZHEJIANG PROVINCE

Forest growth in relation to variation of soil properties variety in Chinese fir forest soils derived from granite with different preceding vegetation in Lishui region of Zhejiang Province. Research results show that no matter what kinds of preceding vegetation the Chinese fir forest had, such as masson pine, broad-leaved forest or shrub, the first rotation of Chinese fir grew faster than the second rotation of Chinese fir. And five years later, the difference in growth became very obvious. The soil under Chinese fir of a second rotation was the lowest in population of bacteria, fungi and azotobacters, but not in that of actinomycete. Compared with other soils different in preceding vegetation, it was lower in activities of invertase and urease. Its content of available P was significantly lower than the others', and so were its contents of calcium and magnesium. Stepwise regression analyses results show that tree growth was positively correlated with invertase activity, available N, available K, and Mg 2 contents and negatively with soil organic matter, urease activity, catalase activity in the Chinese fir forest soils different in preceding forest stand.