辽东山地老秃顶子冰缘地貌植物群落稳定性研究

Mt. Laotudingzi in the eastern Liaoning Province is a mid-size mountain, also is the highest peak in Liaoning Province, located in the core region of Liaoning Laotudingzi National Nature Reserve. It is the southwest extension part of Changbai Mountains Longgang branch. Because of the influence of Quaternary glacical climate, some areas formed periglacial landforms which are rock block field, rock stream, rock glacier side, commonly called Tiaoshitang or Luanshijiao landform. Vegetation community grown in the landform made great contribution to stabilize and contact the special habitat. To a great extent, whether there is debris flow such a major geological disaster or not, depends on the vegetation community stability. Based on this, the authors chosen the periglacical landform from core region of Liaoning Laotudingzi National Reserve as the research samples. Used combinative methods such as field plots survey, laboratory testing and quantitative analysis in the research. First of all, through the testing of vegetation number, determined the community types, composition structure and site environment characteristics of the rock block field, rock stream, rock glacier side. Also the authors determined the diversity of community species and the niche of dominant species, and its degree of succession, then applying the analytic hierarchy process and community stability comprehensive index calculation method, meanwhile, using M. Godron stability calculation method to determine the stability of vegetation community which grown in rock block field, rock stream, rock glacier side. This study could be a scientific basis for the periglacial landform's vegetation management and protection in eastern Liaoning Province.

辽东中山山地老秃顶子为辽宁省最高峰，地处辽宁老秃顶子国家级自然保护区核心区内，属长白山脉龙岗支脉向西南延续部分，局部地段因受第四纪冰川气候的影响，形成了大面积石海、石河和石流坡冰缘地貌，俗称跳石塘或乱石窖地貌，其上发育的植物群落对该特殊生境起着稳定和联合的作用，植物群落的稳定性很大程度上决定着该区域发生泥石流重大地质灾害的危险性。基于此，本项目以辽宁老秃顶子国家级自然保护区核心区内的冰缘地貌为研究样地，采用野外样地调查、室内实验测试和定量分析相结合的研究方法，首先运用植被数量分析法，确定自然干扰状况下石海、石河和石流坡的植物群落类型、组成结构及立地环境特征，测度群落物种多样性、优势种群的生态位和群落的演替度，然后运用层次分析法和群落稳定性综合指数测算法，同时运用M.Godron稳定性计算法，综合测度石海、石河和石流坡植物群落的稳定性。该研究可为辽东山区冰缘地貌植被的经营和管护提供科学依据。

辽东中山山地老秃顶子为辽宁省最高峰，属长白山脉龙岗支脉向西南延续部分，局部因受第四纪冰期气候的影响，形成了大面积古冰缘地貌，俗称跳石塘或乱石窖，其上发育的植物群落对该特殊生境起着稳定和联合的作用，植物群落的稳定性很大程度上决定着该区域发生泥石流重大地质灾害的危险性。基于此，本项目以辽宁老秃顶子国家级自然保护区核心区内的古冰缘地貌为研究样地，采用样地调查、实验测试、植被数量分析和数理模型分析相结合的研究方法，对古冰缘地貌立地环境特征、植物群落特征、群落演替度及主要种群的生态位特征进行系统研究；对古冰缘地貌植物群落稳定性内涵的界定进行探讨，并依此内涵，从植被、基质、地形、土壤、气象5方面综合选取30个易获取和测度的因子，构建评价指标体系，应用熵权物元可拓模型，对古冰缘地貌植物群落稳定性进行定量评价；同时对古冰缘地貌植物群落的M.Godron稳定性进行测度。主要研究结果为：（1）老秃顶子古冰缘地貌石海集中分布在相对平缓的峰顶，面积较小，砾石间隙土层深厚；石河分布在沟谷地带，石流坡则分布在基岩坡面上，都呈现出砾石混乱无序搭接、砾石面基本为苔藓包被、砾石间隙土层薄厚不均的特征，都具有少土多石、砾石易翻滚的不稳定基质环境。（2）古冰缘地貌植被可划分为落叶阔叶林、针阔混交林、暗针叶林、矮曲林、灌丛、灌草丛6个植被型，其分布格局主要受控于山地不同海拔高度水热因素的制约，而冰缘地貌独有的基质环境、更为冷湿的小气候和厚度不均的土壤条件对其只产生一定影响。（3）古冰缘地貌植物群落物种多样性指数大小依次为石河>石流坡>石海。群落中臭松冷杉、狗枣猕猴桃、单花忍冬、大翅卫矛、关东丁香、东北羊角芹、荨麻叶龙头草、酢浆草的生态位较宽，已成为研究区的泛化植物种；群落中主要种群间生态位重叠较为普遍，但重叠程度较高的种对较少。（4）古冰缘地貌森林、灌丛、灌草丛的演替度分别为277~862、158~221、115~157，群落演替程度较高。（5）应用熵权物元可拓模型评价，古冰缘地貌植物群落的稳定性水平达到中等和较高的样地占80%以上，可认为本区植物群落稳定性整体水平较好。（6）运用M.Godron稳定性测算，古冰缘地貌植物群落的累积种类百分数与累积相对重要值比值在25/75~33/67之间变动，与20/80的群落稳定点接近。上述研究结果可为辽东山区古冰缘地貌植被的更新、现代冰缘地貌植被的建植提供科学依据。