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利用湖北省马尾松人工林的样地资料 ,建立了优势高 (Ho)生长方程、林分自然稀疏方程、未疏伐林分直径生长方程、疏伐后林分生长预测方程、直径分布模型、树高曲线方程 ;根据现场造材资料 ,建立了材种出材率预测模型。根据生长与收获相容性原理 ,采用立木蓄积平均生长量最大确定数量成熟龄 ,确定工艺成熟龄为材种材性达到工艺要求的最低年龄 (15a) ;采用贴现法 (基准贴现率为 12 % )进行经济分析 ,以净现值 (NPV)最大(适当考虑内部收益率IRR)来确定经济成熟。根据“以工艺成熟为基限 ,重点考虑经济成熟 ,适当兼顾数量成熟”的原则 ,确定不同立地、不同栽培模式下马尾松纸浆林的主伐年龄及不同种源、不同立地指数的最佳经营模式 ,提出湖北省马尾松纸浆林的主伐年龄在 15～ 2 6a之间。研究了立地、种源、经营状况 (初植密度 ,间伐 )与主伐年龄的关系 ,在同等条件下 ,南带种源比北带种源的各种成熟龄缩短 ,经济效益明显提高 ;随立地指数增加 ,各种成熟龄提前 ,随间伐次数增多 ,数量成熟龄加大
Based on the plot data of masson pine plantations in Hubei Province, the dominant growth equation, the natural sparseness equation, the diameter growth equation of unsweetened forest, the growth prediction equation of diameter thinning, diameter distribution model, Tree height curve equation; According to the field of building materials, the establishment of a timber timber production rate prediction model. According to the principle of growth and harvest compatibility, the maximum number of ripening stalks was determined according to the average growth volume of stumpage, and the minimum age (15a) ) To conduct an economic analysis to determine the maturity of the economy with the largest net present value (NPV), with due regard to internal rate of return (IRR). According to the principle of “maturity of technology as the key point, with emphasis on economic maturity and due consideration of quantity maturity”, the best management mode of the cutting age of Pinus massoniana pulp forest in different sites and different cultivation modes and different site sources and different site indices was determined, Proposed the main cutting age of the Masson pine pulp forest in Hubei Province between 15 ~ 2 6a. Under the same conditions, the maturity ages of provenances in the southern belt were shorter than those in the north belt, and the economic benefits were significantly improved. With the same conditions, the relationship between stand source, provenance, management status (initial planting density, thinning) Index increased, all kinds of mature age in advance, with the number of thinning increased, the number of mature age increased