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以上海浦东沿海水杉基干林带为研究对象,分析水杉林分间伐以及间伐后林下套种其他树种构建复层林2种结构调控措施下林分冠层及林地土壤的变化。结果表明:间伐和复层林构建可显著促进上层乔木树高和胸径的生长,也有助于林下乔灌木和草本植物的发育;未间伐水杉林带LAI最高,其次为复层林带,间伐林分最低。各林分林隙分数的分布特征与LAI相反;3种林分土壤全N、全P和速效K含量差异不显著,而间伐林和复层林土壤速效P、水解N和有机质含量比未间伐林有进一步改善,但间伐林分和复层林带之间土壤养分状况没有显著差异;林分结构调控增加了0～50cm土壤有机碳储量,其中以0～15cm土层有机碳密度最高。复层林带和间伐林土壤呼吸速率比未间伐林分别提高了42%和33%。
In order to study the changes of canopy and forest soil under the two structural control measures of Melaleuca alterniflora in the coastal belt of Pudong, Shanghai, this paper analyzed the effects of two measures on the structure and establishment of the multi-layered forest. The results showed that thinning and multi-layer forest construction could significantly promote the height and DBH growth of the upper tree, and also contribute to the development of the trees, shrubs and herbs in the forest. The LAI of the forest was the highest, followed by the cascade forest belt, lowest. The distribution characteristics of gap fraction in each stand were opposite to LAI. The content of total N, total P and available K was not significant in the three stands, but the contents of available P, There was no significant difference in soil nutrient status between thinning and multi-layer forest belts. Soil organic carbon storage in 0-50 cm soil layer was increased by structural adjustment of stand structure, of which, organic carbon density was the highest in 0-15 cm soil layer. The soil respiration rate in the multi-layered forest belt and the intermediate deforestation increased by 42% and 33% respectively compared with the control.