【作者】 刘翠玲；

【导师】 潘存德；

【作者基本信息】 新疆农业大学 ， 草业科学， 2009， 博士

【摘要】 阿尔泰山的山地森林是西西伯利亚山地南泰加林在南端的延伸和楔入草原地带的北方暗针叶林的代表。喀纳斯作为阿尔泰山(中国)的一颗璀璨明珠,浓缩了阿尔泰山自然生态系统和景观的精华,保存有以泰加林为代表的原始生态系统,系我国惟一的古北界欧洲-西伯利亚动植物分布区,具有很高的自然保护价值和科学研究价值。同分布于世界其他寒温带地区的森林一样,自然火干扰作为千百年来泰加林演替和生生不息的主要推动力,对喀纳斯森林景观发挥着“创造”与“破坏”的双重作用,对其森林景观群落结构与景观美学价值的形成和维持有着深刻的影响。因此,“森林景观美学质量形成机制与自然火干扰体制”是喀纳斯以“视觉质量”或“风景质量”为价值取向的森林经营中不可回避并具有深远影响的科学命题,从发生机制上探索森林景观群落结构,尤其是乔木层树种结构及其外观表征的形成与维持则构成这一科学命题的主要内容。鉴于此,本研究将喀纳斯泰加林原始生态系统作为研究对象,采用典型样带、典型样方、林木火疤调查和森林景观美景度评价法,以喀纳斯森林景观树种结构垂直格局研究为起点,从自然火干扰体制出发,以包括水平结构、垂直结构、季相结构和组成结构在内的森林景观树种结构对自然火干扰的时空动态响应为纽带,探讨了喀纳斯森林景观美学质量的表现形式和动态变化,揭示了以树种结构为物质载体的喀纳斯森林景观在自然火干扰驱动下的美学质量形成机制。研究结果如下:(1)在垂直空间上,喀纳斯森林群落树种结构复杂,五彩的森林群落奠定了喀纳斯森林景观美学质量的物质基础。西伯利亚落叶松(Larix sibirica Ldb.)、西伯利亚云杉(Picea obovata Ldb.)、西伯利亚红松(Pinus sibirica Ldb.)和疣枝桦(Betula pendula Roth.)是构成喀纳斯森林群落的主要乔木树种,群落树种组合丰富。在1900m以下的较低海拔区,树种组成表现为由西伯利亚落叶松、西伯利亚云杉和疣枝桦为主的针阔混交林,树种丰富度相对较高。而在1900m以上的较高海拔区,树种组成则表现为以西伯利亚落叶松和西伯利亚红松为主的针叶混交林,树种丰富度相对较低。在整个海拔梯度范围内,森林群落树种季相结构和组成结构指标值随海拔高度的增加呈极显著的下降趋势。但在整体下降趋势中,季相结构和组成结构指标值的减小又表现出一定的区域性,即在1900m以下的较低海拔区,树种结构指标值相对于1900m以上的较高海拔区要高。就整个垂直空间而言,树种季相结构和组成结构的空间自相关格局在中小尺度上表现明显,空间结构性较强。(2)喀纳斯不仅地形地势复杂,水热组合多样,更重要的是它属于林火多发地带,独特的生态环境和频发的自然火干扰塑就了喀纳斯森林景观的树种结构。在大尺度上,海拔高度影响着整个尺度范围内森林景观树种季相结构和组成结构的垂直分布格局。除此之外,坡度、坡位和土壤养分对大尺度上森林植被的分布特征也有一定的贡献。但在中小尺度上,自然火干扰则发挥着主导作用。自然火干扰事件发生后残留火疤木的分布格局表明,在喀纳斯,自然火干扰事件主要集中分布在1900m以下的较低海拔区,且事件发生时间和干扰烈度各不相同。在自然火干扰的驱动下,森林景观构成丰富,表现形式多样。但在1900m以上的较高海拔区,自然火干扰痕迹少见。在自然状态下,长期未受自然火干扰作用的林分树种构成简单,而且其树种季相结构和组成结构指标值极显著低于受自然火干扰林分。与此同时,树种的季相结构和组成结构对自然火干扰表现出明显的时间效应,但对自然火干扰的烈度反映并不敏感。受不同时期发生的自然火干扰作用后,林分现有的季相结构和组成结构均存在显著差异。(3)自然火干扰通过营造喀纳斯森林景观的树种结构,进而深刻影响着以视觉质量为价值取向的森林景观美学价值的具体表现和动态变化。喀纳斯地形地貌复杂多变,森林景观美学质量整体较高。然而,自然火干扰通过影响中小尺度上树种的季相结构和组成结构致使阔叶针叶树种比大、树种丰富、林相整齐的森林景观更为人们所青睐。随着时间的推移,喀纳斯森林景观美学质量表现出与森林发生自然火干扰时间早晚密切相关的特征。就森林景观当前所表现的美学质量而言,具有较高美学价值的林分所经历的自然火干扰发生时间距今较近,具有较低美学价值的林分所经历的自然火干扰发生时间距今较远。基于径向基函数人工神经网络技术预测的喀纳斯森林景观美学质量动态变化同样验证了这一规律。事实证明,在森林演替过程中,自然火干扰有利于喀纳斯森林景观美学价值的体现,推动着喀纳斯五彩森林景观的可持续发展。更多还原

【Abstract】 Altaic Mountain forest not only is extension of West Siberia southern taiga in the south, but also is the characteristic of dark-coniferous boreal forest which extended grassland district. Forest of Kanas National Nature Reserve, acting as the most famous noted sights of Altaic Mountain, condenses essence of Altaic Mountain natural ecosystem and scenery, and conserves virgin taiga ecosystem. Kanas National Nature Reserve is the unique Europe-Siberian plants and animals region within palaearctic distribution in China and has obvious value of protection and research. Like other forests lied in cold temperate district, natural fire disturbance, one of the most important disturbance factors in taiga, improves continually the succession of forest in Kanas National Nature Reserve. As to forest scenery of Kanas National Nature Reserve, natural fire disturbance has double effects of“creation”and“destruction”. What is more, natural fire disturbance plays a significant role in formation and maintenance of forest community structure and scenery aesthetic quality. Therefore, study about formation of forest scenery aesthetic quality and natural fire disturbance regime of forest is an invoided scientific problem in forest management of Kanas National Nature Reserve. From the originating mechanism viewpoint, to explore the formation regime and dynamic of forest scenery aesthetic quality based on structure is the most main content. On the basis of the above recognition, this thesis regarding virgin taiga ecosystem in tourism district of Kanas National Nature Reserve as research objection, descripts quantitatively quantitative characteristic of historic fire disturbance in dark-coniferous forest, and explores the formation regime of forest scenery aesthetic value based on the temporal and spatial dynamic response of forest structures of tree species to fire disturbance. The methods of this study include typical transect investigation, typical community sampling plot method, the analysis of fire scars and scenic beauty estimation method(SBE). Structures of tree species are composed of horizontal structure, vertical structure, seasonal structure, composition structure and include seven indexes. The main results show:(1)Structures of tree species in forest community was complicated and various, colorful forest community is material basis of forest scenery visual quality in Kanas. The main arbor tree species in forest community in Kanas are Larix sibirica Ldb., Picea obovata Ldb., Pinus sibirica Ldb. and Betula pendula Roth.. With altitude increasing, the main composition pattern of tree species is formed by broadleaf-conifer mixed forest at the lower of altitude 1900m, species richness of tree is higher. Tree composition structure is conifer mixed forest at the higher of altitude 1900m; species richness of tree is lower. The changes of percentage of different species with increasing elevation are different. And tree seasonal structure and composition structure display distinct downtrend along altitudinal gradient across all scales. But in whole downtrend, tree seasonal structure and composition structure along altitudinal gradients show regional characteristic, altitude 1900m as a division. Species richness of trees and proportion of tree species at the lower of altitude 1900m is higher than that at the higher of altitude 1900m. Furthermore, spatial autocorrelation of tree seasonal structure and composition structure are obvious at middle or small scales, spatial heterogeneity along altitudinal gradients in the same scale ranges are distinct.(2)Terrain is complex, hydro-thermal characteristic is diverse in Kanas. Furthermore, there are many natural fire affairs. Special ecological environment and frequency natural fire disturbance improve the formation of structures of tree species. In large scale, the elevation is the fundamental factor to influence the altitudinal pattern of tree seasonal structure, composition structure. Slope, aspect and soil nutrients also dominant the pattern of Kanas forest vegetation. But in middle or small scale, natural fire disturbance is the main factor which controls structures of tree species. The analysis of temporal and spatial distribution of fire disturbance show that the fire affair mainly occurred at the lower of altitude 1900m. The time of fire affair and severity of each natural fire disturbance is different. Forest scenery is various with fire disturbance. But at the higher of altitude 1900m, there is little fire affair and the trace of fire disturbance is unusual. There is distinctly different between stand with natural fire disturbance and stand without natural fire disturbance as for structures of tree species in Kanas. Forest seasonal structure and tree composition structure are markedly affected by natural fire disturbance. And the indexes of structures of tree species are higher in disturbance plot than ones in stand without disturbance in Kanas. What is more, proportion of tree species and species richness of tree have obvious variance to different period fire disturbances,but they have not significant difference to different fire disturbance severity. Fire disturbance is one of the main factors which control the structures of tree species.(3)In Kanas, natural fire disturbance controls formation of forest scenery structure and affects the scenic beauty of forest scenery value. The scenic beauty of forest scenery value in Kanas is universally higher. However, people prefer the forest scenerys with richer tree species and orderly storey. And these forest scenerys represent higher aesthetic value. There is a close relationship between forest scenery visual quality and the occurring time of natural fire disturbance. The forest scenery which is impacted by the early natural fire disturbance has lower aesthetic value, vice versa. It also can be confirmed by radial basis function. Fire disturbance is one of the main factors which influence the forest scenery visual quality by controlling the formation of structures of tree species. In sum, in the process of forest succession, natural fire disturbance is useful to embodiment of forest scenery visual quality and the sustainable development of tourism in Kanas.更多还原