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辽宁省西部营造有大量用于水土保持的油松人工纯林。如何改造这些低效的纯林是生产实践中面临的一个严重问题。根据近自然林业思想,通过实践提出了带状皆伐栽植阔叶树,块状皆伐栽植阔叶树和林中空地、林缘等栽植阔叶树改造现有的油松纯林具体方法。论述了改造的对象和树种选择等问题,并详细介绍了每种方法的关键技术及其应用条件。通过实际调查和对比分析,对经过带状改造的油松林进行了评价。结果表明,16年后,采用上述方法改造的油松林具有明显的分层结构,林下植物物种多样性增加了23.5%52.9%,土壤脲酶、磷酸酶和蔗糖酶活性比对照分别提高了6%142%,46%99%和31%200%,松毛虫危害得到有效控制,水土保持功能也得到提高。图2表3参37。
The western part of Liaoning Province has created a large number of artificial pure forests for the conservation of soil and water. How to transform these inefficient pure forests is a serious problem in production practice. According to the idea of near natural forestry, the concrete methods of transforming the existing pure plantation of Pinus tabulaeformis were proposed through practicing the methods of cutting the planted hardwood tree such as banded clearcut tree, clear - cut planted hardwood block and forest open space, forest edge and so on. Discussed the transformation of the object and tree species selection and other issues, and introduced in detail the key technologies for each method and its application conditions. Through the actual investigation and comparative analysis, we conducted the evaluation on the pine-tree forest transformed by the belt. The results showed that after 16 years, the Pinus tabulaeformis forest modified by the above method had obvious stratification structure, the species diversity of understory plants increased by 23.5% and 52.9%, and the soil urease, phosphatase and invertase activities increased by 6% 142%, 46%, 99% and 31%, 200% respectively. The damage of pine caterpillars is effectively controlled and the functions of water and soil conservation are also improved. Figure 2 Table 3 Reference 37.