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自养机制的形成是人工林可持续经营的目标之一.本研究通过混交模拟杉木人工林不同恢复阶段林分,观察比较发现从退化的杉木林阶段到地带性树种比例较低的混交林、地带性树种比例较高的混交林和地带性树种纯林阶段凋落量、N、P、K、Ca和Mg5种元素的归还量逐渐增加,特别是5种养分元素的循环速率也不断增大,其中N、Mg的循环速率由杉木纯林的0.1左右增大到火力楠纯林的0.5以上,与此同时林分土壤有机质含量和养分含量也不断增加,表明退化杉木人工林在恢复过程中随着林内地带性火力楠树种混交比例的增加,林分的自养机制逐渐获得重建.从杉木人工林可持续经营角度来看,杉阔混交比例的确定应以林分自养机制的形成和土壤养分状况的改善为标准
The formation of autotrophic mechanism is one of the goals of sustainable management of plantation.This study simulated mixed stands of Chinese fir plantation at different restoration stages, observed and compared found that from the stage of Chinese fir plantation degradation to mixed forest with lower proportion of zonal species, The litterfall, the return of N, P, K, Ca and Mg increased gradually in mixed forest and zonal tree species with higher proportion of zonal species, especially the cycling rate of five nutrient elements , And the cycling rate of N and Mg increased from about 0.1 of Chinese fir plantation to above 0.5 of pure plantation. At the same time, the content of soil organic matter and nutrient content also increased continuously, indicating that during the restoration of degraded Chinese fir plantation, With the increasing proportion of mixed firewood species in the forest, the self-supporting mechanism of the forest gradually rebuilt.From the perspective of sustainable management of Chinese fir plantation, the proportion of Chinese fir and broad mixed forest should be determined by the formation and Improvement of soil nutrient status as a standard