岷江干旱河谷豆科植物多样性及其空间格局  

Species Diversity and Spatial Distribution of Legumes in the Dry Valley of Minjiang River,SW China

作　　者：李芳兰[1] 包维楷[1] 朱林海[1] 

机构地区：[1]中国科学院成都生物研究所生态恢复重点实验室,四川成都640041

出　　处：《山地学报》2010年第1期76-84,共9页Mountain Research

基　　金："西部之光"博士资助项目(08C2041100);中国科学院山地生态恢复与生物资源利用重点实验室开放基金(08B2011106);中国科学院知识创新工程项目(KZCX2-XB2-02)共同资助~~

摘　　要：为研究岷江干旱河谷的豆科植物物种多样性及其在纬度和海拔梯度上的分布格局,在从四川汶川到松潘的干旱河谷两岸选择了7个地点,通过204个样方(2m×2m)调查,分析了不同纬度和海拔豆科物种组成、高度、盖度与根系结瘤的空间分布特点。结果表明:(1)在所有样方中共出现乡土豆科植物16属,38种,其中灌木7属19种;草本植物7属17种,1或2a生草本6种,多年生草本11种。仅刺槐(Robinia pseudoacaciaL.)和葫芦巴(Trigonellae foenum-graecumL.)为栽培物种。灌木在该地区豆科植物中占较大优势,50%以上灌木的频度与盖度均>10%,尤其白刺花(Sophora davidii)、小马鞍羊蹄甲(Bauhinia brachycarpavar.microphylla)、岷谷木蓝(Indigo-fera lenticellata)等灌木频度>20%,而所有草本植物的频率及盖度都<10%。(2)豆科植物丰富度及生长具有较为明显的空间差异,干旱河谷核心地区的干热、贫瘠环境中,总物种丰富度较高,但是其盖度与高度较小。随着纬度升高,灌木丰富度和频度均减少,草本丰富度与和频度增加。随着海拔上升,灌木丰富度与总物种丰富度都减小,草本植物丰富度变化不明显;植物平均高度与盖度高度也无明显的垂直变化规律。(3)植物根系结瘤能力很低,66%物种未结瘤,并且幼苗结瘤能力显著大于成株。这一结果可为豆科植物资源的保护和开发利用提供科学依据。Legumes and their ability in N2 fixation play an important role in sustainable agricultural practices and ecological restoration of degraded lands.To explore the composition,growth,nodulating ability and spatial distribution of legumes in the dry valley of Minjiang River,southwest of China,we set totally 204 sampling plots of 2 m × 2 m.The results indicate：1）there are 38 legume species in the dry valley including 2 cultivated ones Robinia pseudoacacia and Trigonellae foenum-graecum.In the native species,19 shrubs belong to 7 genera and 17 herbs belong to 7 genera;most of the herbs are perennial.Obviously,shrubs were dominant in the legume communities of this area;more than 50% of shrubs had frequencies higher than 10%,specially in Sophora davidii,Indigofera lenticellata and Bauhinia brachycarpa var.microphylla with frequencies higher than 20%,while all herbs had frequencies less than 10%.2）The species richness and growth had distinctly spatial differences：a higher species richness and lower plant height were observed at the middle of the dry valley（N 31°42＇9.6″~31°42＇36.2″）where habitats are dry and infertile;shrub species richness decreased with the increasing of latitude,while herb species richness increased.The richness of the total legume species decreased along altitudinal gradients;shrubs＇ richness changed similarly with the total species richness,but the altitudinal richness pattern of herb species was quite inconspicuous.The height of shrubs increased along the altitudinal gradients,but herbs changed indistinctively.3）There were very few nodules in roots of the legume species growing in the dry valley,and no-nodulating species accounted for 66% in this study.The seedling with higher nodulating ability than adult plant.The results of our study will precede a discussion of the role of legumes in natural ecosystems in the dry valley and how they may be exploited in a sustainable way.

关 键 词：干旱河谷 豆科植物 物种丰富度 分布规律 环境因子 

分 类 号：Q948.2[生物学—植物学]