摘要
探索山地乔灌木斑块的空间分布格局及其多样性与海拔的关系,对于揭示区域植物的环境适应性、实施区域生物多样性保护和生态系统修复具有重要意义。基于第三次林业普查数据,借助地理信息系统的分析方法,分析了横断山脉北段一二级阶梯过渡带乔灌木斑块的空间分布格局及其多样性沿海拔梯度的变化规律。结果表明:①过渡带的乔灌木总计37科72属103种,乔木(56种)略多于灌木(47种),乡土物种占比99.03%,中国特有物种占比22.33%。过渡带中的优势树种为:冷杉、云杉、高山松、高山栎、矮桦和落叶松;优势灌木为:高山杜鹃、灌状高山栎、杯腺柳、杜鹃、忍冬和野蔷薇。②水平格局显示,灌木斑块总面积约为乔木斑块的1.24倍,优势地位明显,但破碎化程度高于乔木。灌木斑块集中连片分布于过渡带的北部、中部和西部。乔木斑块则沿金沙江、雅砻江和大渡河等流域呈现带状分布。海拔梯度显示,在过渡带的低海拔、高海拔和极高海拔区域,灌木斑块所占面积均高于乔木斑块,但在中海拔区域乔木斑块所占面积约为灌木斑块面积的1.80倍。③多样性分析显示,过渡带的乔灌木多样性较好,且乔木的多样性优于灌木。其东部区域的乔灌木多样性最好,其中,泸定和九龙县的乔木多样性最优,泸定和丹巴灌木多样性最优。随海拔梯度的增加,乔灌木的丰富度(PR,Patch Richness)值呈单峰趋势,乔灌木的Shannon′s多样性指数(SHDI,Shannon′s Diversity Index)和Shannon′s均匀度指数(SHEI,Shannon′s Evenness Index)值虽呈双峰模式,但三者在中海拔区域的值均为最大,多样性变化趋势符合“中间高度膨胀”类型。仅有灌木的SHEI值及乔灌木总的SHEI值与海拔的增长存在显著负线性相关。
Exploring the spatial distribution pattern of mountain tree⁃shrub patches and the relationship between their diversity and altitude are important for revealing the environmental adaptability of regional plants and implementing regional biodiversity conservation and ecosystem restoration.Based on the data of the third forestry census,this paper analyzed the spatial distribution pattern of tree and shrub patches and their diversity variation along the altitude gradient in the transition zone between the first and second steps of the northern Hengduan Mountains using the method of geographic information system.The results showed that:①There were 103 tree⁃shrub species belong 37 families and 72 genera in the transition zone.The number of tree species(56 species)was slightly more than that of shrub(47 species).The proportion of native species was 99.03%and the proportion of endemic species in China was 22.33%.The dominant tree species here were Abies fabri,Picea asperata,Pinus densata,Quercus semecarpifolia,Betula potaninii,and Larix gmelinii,while the dominant shrubs in the transition zone were Rhododendron lapponicum,Quercus aquifolioides,Salix cupularis,Rhododendron simsii,Lonicera japonica,and Rosa multiflora.②The horizontal pattern showed that the total area of shrub patch was about 1.24 times that of tree patch,showing obvious dominance.However,the fragmentation degree of shrub patches was higher than that of trees.Shrub patches were distributed in the northern,central,and western transition zone.The tree patches distributed in bands along the Jinsha River,Yalong River and Dadu River.The area of shrub patches was higher than that of tree patches in the low⁃,high⁃,and extremely high⁃altitude areas of the transition zone,but the area of tree patches was about 1.80 times that of shrub patches in the middle⁃altitude area.③Diversity analysis showed that the diversity of tree⁃shrub in the transition zone was good,and the tree diversity was better than that of shrub.The eastern region of the transit
作者
田蕾
周璐
孙佳瑞
宗桦
TIAN Lei;ZHOU Lu;SUN Jiarui;ZONG Hua(Department of Landscape Architecture,Southwest Jiaotong University,Chengdu 610097,China;China Railway Second Academy Engineering Group Co.,LTD.,Chengdu 610031,China)
出处
《生态学报》
CAS
CSCD
北大核心
2023年第24期10320-10333,共14页
Acta Ecologica Sinica
基金
国家自然科学基金面上项目(31971716,32271945)
成都市科技局技术创新研发项目(2021⁃YF05⁃00033⁃SN)
成都市中铁二院横向项目(KYY2019132)。
关键词
山地
乔灌木斑块
空间分布格局
物种多样性
海拔
mountain
tree and shrub patches
spatial distribution pattern
species diversity
altitude
