<正>应用温室盆栽试验方法，采用完全随机试验设计，研究了1年生落羽杉实生苗在不同土壤盐分和水分条件下超氧化物歧化酶（SOD）、硝酸还原酶（NR）、苯丙氨酸解氨酶（PAL）和过氧化物酶（POD）等几种酶的活性及丙二醛（MDA）的含量。试验共设4种盐分水平（NaCl含量为土壤干重的0%、0.15%（S1）、0.3%（S2）和0.45%（S3））、5种水分水平（W1指淹水；W2指渍水；W3、W4和W5指土壤含水量分别为田间持水量的75%、50%和25%）及盐分和水分的交互处理等20种处理，时间为130d。结果表明，20种处理下落羽杉叶片SOD、NR、PAL和POD活性及MDA含量差异均达到了极显著水平。双因素方差分析表明，不同的水分水平、盐分水平，以及水分和盐分交互效应对落羽杉叶片SOD、NR、PAL和POD活性及MDA含量的影响差异均达到了显著差异水平。

On the basis of measuring the woody species composition in Schima superba and Pinus massoniana community of a permanent plant transect, which is 10 m× 1 200 m along a altitude from 50～480 m above sea level, on Dinghushan Biosphere Reserve, the quantity traits, the distribution in vertical layers and spatial pattern of the dominant woody species were analyzed, the regeneration strategy and structure traits of the community were studied. The results are as follows., the spatial patterns of the wood species in arbor layer and shrub layer were aggregated distribution except P. massoniana which were random distribution in mature-layer and old-layer. The population of S. superba was stable in the community, where individuals were dispersed in vertical layers evenly. The population of P. massoniana was on declining trend, no individuals appeared in seedling layers. The shrub species use different regeneration strategy with that the tree species use. There are much more seedlings of shrub species than that of tree species. The much more growth resistance of arbor species appeared at the stages from seedling to juvenile. For the shrub species, growth resistance was high in each stage. Meanwhile. the similarity index using space resources among the shrub species was higher than that in tree layer. Same result was concluded from species competition, too. In general, with growing, the trend of aggregation of population in tree layer w～s decrease and lhe reverse resuh was found in the shrub layer.