关键词: 森林资源监测, 云南省, 云南松林

Abstract:

In order to understand the dynamic change and provide decision basis for sustainable management of Pinus yunnanensis forest resource in Yunnan Province, monitoring data obtained by continuous forest inventory during 1987-2007 was analyzed by applying mathematical statistics and chart analysis methods. Based on the analysis of variation of the forest areas, stock volume, quality and structure, the dynamic variation rule of the forest was revealed with plenty of detailed data from various angles. The result show that the resources of the forest continue to grow during 1987-2007, and the growing rate was increased rapidly during 1997-2002, when the Natural Forest Protection Project had been implemented (the total stock volume of the forest increased from 20462.33×104 m³ to 22243.65×104 m³, which is over 20.57% in five years time). On the same time, however, the percentage of over-mature Pinus yunnanensis forest was relative low and the stock volume of high quality, available resources of the forest continuously decline, and was close to exhaustion. The result also shows that the unit area stock volume of the forest had increased 27.05% in 20 years, while the volume of large or super- large timber showed a descending tendency in this period, especially the percentage of super- large timber decreased from 19.9% to 6.8%, being only the 1/3 of the original. The stock volume of the individual plant in near-mature, mature and over-mature forest fell to 0.22 m³ from 0.77 m³, which indicated that the resources available for logging were decreasing rapidly, and the tendency of poorer quality of timber structure was exacerbated while the general quality of the forest was improved. The age structure of Pinus yunnanensis forest in Yunnan Province show a remarkable characteristic of lowering ages trend, and this highlighted the importance of nursing and scientific management of the forest. The analysis also showed that the variation of dominant utilization types of Pinus yunnanensis forest in 20 years was significantly adverse to the effective management of the forest. The Pinus yunnanensis forest rehabilitated during monitoring period benefited from the protection- oriented policy, however, the management of the forest still presented problems, such as extensive management, randomly regulation of management objective and over-use of mature and over-mature forest resources etc., and the interaction of the above mentioned problems led to the fluctuation of resources quantity, stand quality and the age structure of Pinus yunnanensis forest in Yunnan Province.

Key words: forest resource monitoring, Pinus yunnanensis forest, Yunnan Province