四川盆地西缘湿性常绿阔叶林不同恢复阶段物种多样性响应

Response of species diversity to restoration succession: the case of the moist evergreen broad-leaved forests in the western edge of Sichuan Basin
Wanze Zhu1*, Xiaohu Cai2, Fei He2, Jinxi Wang2
周山地天然、次生常绿阔叶林群落学特征、外貌、 结构(马丹炜, 1998; 包维楷和刘照光, 2002)、群 落数值分类和排序(梅炯杰等, 1992), 以及土壤 形成、营养状况、肥力特征(唐时嘉, 1990; 寥咏 梅等, 2003)等进行了研究, 但在植被恢复中物种 多样性响应等方面的研究还很薄弱。
—————————————————— 收稿日期: 2005-07-11; 接受日期: 2005-11-21 基金项目: 青藏高原生态系统对环境变化的响应(2005CB422005)和长江上游退化天然林恢复与重建技术研究与示范(No. 2001BA 510B060101) * 通讯作者 Author for correspondence. E-mail: wzzhu@
常绿阔叶林是亚热带地区的地带性植被, 是 亚热带陆地生态系统的重要组成部分(吴征镒, 1980; 李昌华, 1997)。四川盆地西缘紧靠横断山 区东缘, 由于复杂的地质历史和有利的生境条件, 是四川省生物多样性最丰富的区域之一(中国生 物多样性国情研究报告编写组, 1994), 区域内常 绿阔叶林不仅分布面积广(占四川省森林总面积 的 15.2%), 而且类型多, 同时又与川西高山峡谷 植被地区的森林连成一片, 是西南林区的重要组 成部分之一(四川植被协作组, 1981)。该区域常绿 阔叶林既是长江流域的重要生态屏障, 也是长江 和成都平原的水源区, 又是许多江河的源头和分 布地段, 如岷江、青衣江、涪江等江河或支流的 发源地, 对于保持水土与涵养水源都具有十分重 要的意义(万涛等, 2003)。但由于长期以来对其功 能和作用认识不够, 这里的常绿阔叶林一直被称 为“杂木林”, 加上人为因素和自然因素的干扰, 其生态功能严重退化, 许多区域已退化为次生类 型甚至次生灌丛, 原始天然林保存较少(万涛等, 2003)。
1 Institute of Mountain Harzard and Environment, Chinese Academy of Sciences, Chengdu 610041 2 Sichuan Academy of Forestry, Chengdu 610081
Abstract: Based on investigation of moist evergreen broad-leaved forests in Anzihe Nature Reserve and Tiantai National Forest Park, located at the western edge of the Sichuan Basin, we studied the response of species diversity to different restoration phases using the technique of space-for-time substitution, the results were as follows: (1) During 350 years of restoration succession, we found a unimodal response of species diversity over time. Species richness and the Margalef index peaked 100 years after the onset of restoration succession, up to 130 and 21.49, respectively. There was a fast increase in arbor species within the first 50 years, and then in shrubs and herbs within 50–100 years phase. The species number and the Margalef index (y) varied according to a parabolic function with time (t): y = y0+at+bt2+ct3. We recommend Lindera limprichitii and Machilus pingii as ideal tree species for afforestation in the study area because of their wide niche; (2) There were greater value of Simpson index during 30–50 years after restoration and value of Shannon-Wiener index during 30–100 years respectively. The variance coefficient of species diversity in the arbor layer was greater than that in the shrub layer. The shrub layer contributed greatly to species diversity of
本文采用空间代替时间的方法, 通过对崇州 市鞍子河自然保护区天然次生林的典型样地调查, 并与原生性较强的邛崃天台山常绿阔叶林进行比 较, 目的在于揭示四川盆地西缘湿性常绿阔叶林 自然恢复演替过程中群落和不同层次物种多样性 的变化规律, 为这一区域湿性常绿阔叶林植被恢 复和重建提供树种选择的理论和实践依据。
植物多样性的恢复是退化生态系统恢复与重 建的重要标志, 植被恢复过程中物种多样性的变 化已成为恢复生态学研究的热点之一(李裕元和 邵明004; 陈世品, 2004; 严岳鸿等, 2004)。常 绿阔叶林退化和恢复重建的研究主要集中在常绿 阔叶林生态系统退化的特征、过程、机制(温远光, 1998; 贺金生等, 1998; 刘世忠等, 1998; 包维楷 等, 2001; 石胜友等, 2002), 恢复和重建(李翠环 等, 2002; 丁圣彦和宋永昌, 2003), 以及种群结 构、物种多样性变化(Manabe et al., 2000; Masaaki et al., 2005)等方面。近年来, 许多学者对四川盆
1 研究区概况
研究区设在四川省崇州市西北部的鞍子河 自然保护区, 103°07′–103°27′ E, 30°41′–30°52′ N, 属邛崃山脉东南支脉龙门山中段、盆地西缘峡谷 地带。境内山高谷深, 海拔 960–3,868 m, 具有典 型的盆周西缘山地特点。该区属中亚热带湿润性 季风气候, 具有云雾多、日照少、湿度大、风速 小等气候特点。多年平均气温 7.5–12℃, 极端最 低气温–8℃, 极端最高气温 32.7℃; 多年平均降 水量 1,300–1,450 mm, 集中于 6–9 月, 约占全年 降水量的 70%; 全年降雨天数为 180 d 左右, 无显 著干旱季节; 年均相对湿度为 86%; 年均日照 641.6 h, 无霜期 200–230 d。保护区土壤以山地黄 壤为主, 主要分布在海拔 2,000 m 以下的退化天 然林区。保护区海拔 2,000 m 以下, 原系常绿阔 叶林带, 目前植被表现出强烈的次生性, 主要为 次 生 常 绿 阔 叶 林 , 以 及 杉 木 (Cunninghamia lanceolata) 、 柳 杉 (Cryptomeria fortunei) 、 水 杉
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生 物 多 样 性 Biodiversity Science
第 14 卷
the whole community, therefore it should be given more concern in the restoration of secondary forests; (3) Species evenness index displayed a fluctuating increase with the restoration process. Pielou index reaching 2.0834 and the McIntosh index 2.4177 after 350 years of restoration; (4) The Whittaker index displayed a fluctuating increase through the whole restoration process, whereas the Sørenson index decreased. Although the restoration of the moist evergreen broad-leaved forest is a long-term process and it will take at least 300 years to recover to its climax community, there is strong resilience, implying that natural recovery is a very effective and efficient way to restore degraded moist evergreen broad-leaved forest and its biodiversity in the study area. Key words: species richness, species evenness, α-diversity, β-diversity, Qionglai Mountains
1 (中国科学院成都山地灾害与环境研究所, 成都 610041) 2 (四川省林业科学研究院, 成都 610081)