Page 150 - 《广西植物》2026年第2期
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3 4 4                                  广  西  植  物                                         46 卷
                 has largely focused on dry ̄hot valley vegetationꎬ and there is a lack of research on the community and ecological
                 characteristics of dry ̄warm valley vegetation. This study used drone photography and the quadrat method to investigate
                 the characteristics and current distribution of the B. bohniana community. The results were as follows: (1) A total of 22
                 surveyed B. bohniana community quadrats recorded 194 vascular plant species belonging to 57 families and 120
                 genera. Fabaceae and Poaceae were the dominant familiesꎬ while Carex and Selaginella were the dominant generaꎻ the
                 flora showed a tropical ̄temperate transitional patternꎬ with 56.52% tropical and 43.48% temperate generaꎻ at the species
                 levelꎬ Chinese endemics dominateꎬ including 51 indicator species of the Jinsha River dry ̄warm valleysꎬ reflecting relict
                 evolution and specialization driven by the Tethys retreat and the uplift of the Qinghai ̄Tibet Plateau. (2) The community
                 exhibited a distinct vertical structureꎬ with shrub layer cover ranged from 30% to 70%ꎬ herb layer from 10% to 50%ꎬ
                 and interlayer from 1% to 3%ꎻ it had a typical drought ̄deciduous appearanceꎬ turning sparse and yellow in the dry
                 season and regreening in the rainy seasonꎬ with a significantly delayed phenology compared to surrounding areasꎻ the
                 species diversity index of the shrub layer was higher than that of the herb layer. (3) The life ̄form spectrum was
                 dominated by hemicryptophytes ( 41. 24%) and phanerophytes ( 34. 54%). Prominent adaptive traits included a
                 predominance of small leaves (microphyllꎬ 50.52%)ꎬ chartaceous (64.06%)ꎬ and a deciduous habitꎬ which indicated
                 convergent adaptation to drought stress. The community shared adaptive strategies with African savannas community and
                 Mediterranean shrubland but had a higher proportion of temperate genera ( 43. 48%)ꎬ highlighting its transitional
                 nature. This study is of great significance for revealing the historical evolution of the Jinsha River valleyꎬ and provides a
                 scientific basis for the ecological conservation of its middle reaches.
                 Key words: Bauhinia bohnianaꎬ dry ̄warm valley shrublandꎬ community characteristicsꎬ species compositionꎬ
                 Jinsha River


                金沙江位于中国西南地区ꎬ跨越青藏高原、横                           80 多年来未见关于丽江羊蹄甲的研究报道ꎮ 2023
            断山脉和云贵高原ꎬ是长江的上游河段( Li et al.ꎬ                      年本项目组在进行云南哈巴雪山省级自然保护区
            2020)ꎬ对维护长江流域生态平衡和生物安全具有                           科学考察时ꎬ在金沙江边发现了以丽江羊蹄甲为
            重要意义ꎬ一直是学界和业界高度关注的热点区                              优势的灌丛群落ꎬ连片面积约 300 hm ꎬ面积较小ꎬ
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            域ꎮ 然而ꎬ随着气候变化和人类活动的日益加剧ꎬ                            却是在深陷的金沙江 V 型峡谷封闭环境下形成的
            金沙江流域生态系统退化严重( 赵冬林和朱仕荣ꎬ                            金沙江干暖河谷特有植被类型ꎬ资源弥足珍贵ꎮ
            2024ꎻ阮长明等ꎬ2024)ꎮ 干暖河谷灌丛是金沙江                        鉴于丽江羊蹄甲灌丛的独特性ꎬ本研究以金沙江
            中游河谷的主要植被类型ꎬ长期以来受河谷、气候                             干暖河谷丽江羊蹄甲灌丛为研究对象ꎬ基于 2022
            等地形塑造及人为影响ꎬ群落呈片段化分布( 沈泽                            年至 2024 年的连续野外调查数据ꎬ运用群落生态
            昊等ꎬ2016)ꎮ 金沙江干旱河谷植被的研究最早可                          学与 GIS 空间分析方法ꎬ拟探讨以下科学 问 题:
            追溯到 1986 年ꎬ武素功等在横断山科学考察中首                          (1)丽江羊蹄甲群落物种多样性、区系成分及生活
            次对此区域的植被进行了记录( 中国科学院青藏                             型谱如何反映干暖河谷生境的筛选效应ꎻ(2) 丽江
            高原综合科学考察队ꎬ1986)ꎮ 云南大学金振洲教                          羊蹄甲群落结构特征ꎻ(3) 群落中金沙江干暖河谷
            授团队自 1991 年起ꎬ对元江、怒江、金沙江的干热                         标志种的现状及生态学意义ꎮ
            河谷及干暖河谷植物区系进行了系统研究( 金振
            洲ꎬ2002)ꎮ 这些研究为了解金沙江流域植物区系                          1  研究区概况与研究方法

            地理学和生态环境植被演替规律奠定了基础ꎮ
                 丽 江 羊 蹄 甲 ( Bauhinia bohniana ) 系 豆 科         1.1 研究区概况

            (Fabaceae) 羊 蹄 甲 属 ( Bauhinia) 落 叶 灌 木ꎬ Chen           研究区位于滇西北哈巴雪山与玉龙雪山之间
            (1938)依据 Forrest15419 号标本而建立ꎮ 迄今所                  的金沙江 V 型河谷底部左岸ꎬ河谷深陷而狭窄( 图
            知ꎬ丽江羊蹄甲仅分布于滇西北丽江、宁蒗、香格                             1)ꎬ属于云南哈巴雪山省级自然保护区实验区ꎮ
            里拉交界的金沙江中段约 100 km 范围内的干暖                          江边最低海拔 1 550 mꎬ周边有江边村、白马厂村
            河谷区域ꎬ是金沙江流域特有种ꎮ 由于分布点少ꎬ                            和咱八村等村寨ꎮ 研究区为石灰岩区域ꎬ其岩石
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