辽西人工林产量及其影响因素研究

Plantation stocks and their affecting factors in western Liaoning Province.

采用实地调查和资料分析方法,对辽西地区人工林生产状况进行了系统分析.结果表明,建国以来,辽西地区人工林蓄积量整体上有显著的增长,人工林平均蓄积量达49.08m3·hm-2,3次森林资源清查期间,人工林蓄积量净增20.19m3·hm-2,增长了5.16倍.但整体蓄积量水平仍较低,平均蓄积增长量仅为全省同期的63.9%,人工林蓄积量也只有全国森林平均蓄积量的51.1%,且区域内部产量水平差异显著,达68.47m3·hm-2.总体上,幼龄林比例偏高,达49%,成熟林单位蓄积量低,仅相当于全国水平的38%.占人工林面积主体的国有林从中龄林到成、过熟林,其蓄积增长量相当于个人和集体林的55.1%和32.3%.用材林单位蓄积量比防护林低36.4%.除了气候、土壤等自然因素外,人工林结构简单、树种组成单一、管理水平低下以及人为破坏严重等可能是导致辽西地区人工林整体产量较低的主要原因.

Employing real-site investigation and data analysis methods,this paper analyzed the distribution of plantation stocks and its affecting factors in western Liaoning Province.The results showed that the average plantation stock of western Liaoning was 49.08 m 3·hm -2,which has been improved obviously since 1949.At the time of the third forest resource investigation,the plantation stock increased 20.19 m 3·hm -2,5.16 times higher than that of the first forest resource investigation.But,the general plantation stock of western Liaoning was still at a rather lower level,with only a 63.5% increase of the whole province and 51.1% of the national average plantation stock at the same period.The difference of plantation stock among cities in western Liaoning was observable,that even reached 68.47 m 3·hm -2.In general,the proportion of young forest was too high,reached to 49% of the total plantation,while the stock of mature forest was much lower,only 38% of the national average level.The plantation stock of national property was only 55.1% and 32.3% of the personal and collective property,respectively.Moreover,the plantation stock of timber forest was 36.4% lower than that of windbreak.Besides climatic factors,simple plantation structure,few forest tree species,and poor plantation management were the main causes of the low plantation stock.