摘要
采用典型样地调查方法,探讨人工林间伐后产生的不同大小林窗对油松根系生长及土壤理化性质的影响。结果表明:阴坡林窗越大,幼苗根系生长越好,且随着幼苗年龄的增加促进效应更为显著;阳坡小林窗幼苗根系的生长优于大林窗;阴坡和阳坡随着林窗增大,枯落物及腐殖质干质量不断增加;阴坡和阳坡在0~10cm土层土壤密度随着林窗增大不断降低;随林窗增大阴坡相同土层土壤含水率不断增加,阳坡则不断降低;阴坡和阳坡相同土层土壤速效磷、硝态氮和铵态氮含量均表现为小林窗〉大林窗〉林下;逐步回归分析表明,铵态氮含量是影响油松幼苗根系生长的主要土壤因子。油松人工林经营中,在阳坡强烈的光照水平下不宜进行过大强度的间伐,而阴坡则可采取高强度间伐创造林窗为种群更新提供条件。
The effects of gap size created by thinning on the root growth of seedlings and physical and chemical properties of the soil in Pinus tabulaeformis plantation were studied by investigation of typical sample plots. Results showed that on shady slope, the seedling root grew better with increasing gap size, and the facilitating effect increased with the age of seedlings; On sunny slope, the seedling root grew better in small gaps than in big gaps. As gap size increased in both shady and sunny gaps, the dry weights of litter and humus increased, while the soil bulk in 0 - 10 cm soil layers decreased. On shady slope, the soil water content increased with increasing gap size in the same soil layer, whereas on sunny slope the soil water content decreased. The contents of available phosphorus, ammonium nitrogen and nitrate nitrogen in the same soil layer were higher in small gaps than big gaps in both shady and sunny gaps. The analysis of step- wise regression suggested that the root growth of seedlings was mainly influenced by the ammonium nitrogen content. In the management of P. tabulaeformis plantation, high intense thinning should not be carried out on sunny slope, due to strong light level; whereas high intense thinning can be implemented on shady slope, which could provide favorable conditions for regeneration of P. tabulaeformis plantation.
出处
《林业科学》
EI
CAS
CSCD
北大核心
2013年第11期16-23,共8页
Scientia Silvae Sinicae
基金
"十二五"国家科技支撑计划(2012BAD22B0302)
中国科学院战略性先导科技专项(XDA05060300)
关键词
油松
林窗
幼苗根系
土壤理化性质
Pinus tabulaeformis
gap size
root of seedlings
physical and chemical characteristics of soil