摘要
地形影响干旱缺水区植被分布与生长,研究地形对林分结构和生物量的影响,有助于选择合理的生长指标指示立地的植被承载力,进而指导森林管理和植被恢复。本研究在六盘山叠叠沟小流域,按照不同坡位和坡向选取华北落叶松人工林样地,调查树高、胸径等林分结构参数,分析华北落叶松林结构和生物量随地形的变化,以及与立地、植被和土壤因子的关系。研究表明:(1)华北落叶松林径级组成以>5~15 cm为主,树高以>5~11 m为主,乔木层生物量为40.7±20.8 t·hm^(-2)。(2)径级和树高分布呈“单峰型”;其中,胸径为>5~10 cm和>10~15 cm较多,两者共占比74.5%,树高为>5~8 m和>8~11 m较多,两者共占比68.3%;从坡向上来看,阴坡的平均胸径和树高最高,其次是半阴坡,半阳坡最低;从坡位上来看,中坡和下坡的平均胸径和树高较高,而上坡较低。(3)乔木层生物量随着坡位的升高而减小,偏离正北方向越远而越小;乔木层生物量主要受林龄、林分密度、坡向和土厚的影响。总体来看,坡向上表现为阴坡的平均胸径、树高、乔木生物量高于其它坡向,坡位上表现为中坡和下坡高于上坡,表明阴坡和中下坡的植被承载力高,后期可以用胸径、树高和乔木层生物量指示立地的植被承载力。
Topography affects the distribution and growth of vegetation in arid and water shortage areas.The effects of topography on stand structure and biomass are studied,which will contribute to select reasonable growth indicators to indicate the vegetation carrying capacity of the site,and then guide forest management and vegetation restoration.In this study,Larix gmelinii var.principis-rupprechtii plantation plots were selected according to different slope positions and slope aspects in the Diediegou watershed of Liupan Mountain,and the stand structure parameters such as tree height and DBH were investigated,and the changes of structure and biomass of Larix gmelinii var.principis-rupprechtii plantations with topography and their relationship with site,vegetation and soil factors were analyzed.The results showed that(1)The diameter class composition of Larix gmelinii var.principis-rupprechtii was mainly>5-15 cm,the tree height was>5-11 m,and the biomass of arborous layer was 40.7±20.8 t·hm^(-2).(2)The distribution of diameter class and tree height was“unimodal”.Among them,there were more trees with DBH of>5-10 cm and>10-15 cm,accounting for 74.5%,and tree height of>5-8 m and>8-11 m,accounting for 68.3%.For slope aspects,the average DBH and tree height of the shady slope were the highest,followed by the semi-shady slope,and the semi-sunny slope was the lowest.For slope position,the average DBH and tree height were higher on the middle and lower slopes,while the lower ones were on the upper slopes.(3)The biomass of arborous layer decreased with the increase of slope position and the farther away from north direction.The biomass of arborous layer was mainly affected by forest age,stand density,slope aspect and soil thickness.In general,the average DBH,tree height and tree biomass of the shady slope were higher than those of other slope aspects,and those of the middle and lower slopes were higher than the upper slopes,indicating that the vegetation carrying capacity of the shady slope and the middle and lower slopes was high,and thus DBH,tree height and tree layer biomass can be used to indicate the vegetation carrying capacity of the site in the future.
作者
邓树剑
白雨诗
王利霞
万艳芳
石建周
于澎涛
Deng Shujian;Bai Yushi;Wang Lixia;Wan Yanfang;Shi Jianzhou;Yu Pengtao(Diediegou Forest Farm in Yuanzhou District,Guyuan City,Guyuan 756000;Ecology and Nature Conservation Institute,Chinese Academy of Forestry,Beijing 100091;Liupanshan forestry Bureau,Guyuan City,Guyuan 756000)
出处
《湖北林业科技》
2025年第4期10-16,共7页
Hubei Forestry Science and Technology
基金
国家自然科学基金委区域创新发展联合基金重点项目“黄土高原干旱缺水区综合植被承载力的形成机制及时空变化”(U21A2005)
“黄土高原泾河流域森林植被水文功能的形成与补偿机制”(U20A2085)。
关键词
华北落叶松
林分结构
生物量
坡位
坡向
Larix gmelinii var.principis-rupprechtii
stand structure
biomass
slope position
slope aspect
