陕北黄土区植被特征对坡面微地形的响应

2016-06-18 07:14卢纪元朱清科陈文思王瑜
中国水土保持科学 2016年1期
关键词:阴坡阳坡原状

卢纪元, 朱清科, 陈文思, 王瑜

(北京林业大学 水土保持与荒漠化防治教育部重点实验室,100083,北京)



陕北黄土区植被特征对坡面微地形的响应

卢纪元, 朱清科†, 陈文思, 王瑜

(北京林业大学 水土保持与荒漠化防治教育部重点实验室,100083,北京)

摘要:为掌握陕北黄土区不同植被特征对坡面微地形的响应,以陕西省吴起县合沟流域半阴、半阳2个坡向的原状坡及其5种微地形为研究对象,分析对比不同坡向各类微地形的物种组成、草本生物量、植被盖度及植物多样性特征。结果表明:1)各类微地形植物群落的物种组成、植被盖度、草本生物量及植物多样性指数多优于原状坡,其中切沟和塌陷的植被状况最优,其次为浅沟和缓台,陡坎最差;2)各类微地形植物群落的Simpson指数与Shannon-Wiener指数变化趋势一致,均为切沟>塌陷>缓台>浅沟>陡坎>原状坡,其中切沟和塌陷的植物群落所处的自然演替阶段高于其他微地形;3)经过15年自然恢复,半阳坡形成以星毛委陵菜、赖草等多年生草本植物为优势种的植物群落,半阴坡形成以铁杆蒿、茭蒿等地带性多年生草本植物为优势种的植物群落,半阴坡各类微地形植物群落的物种组成状况、草本生物量、植被盖度以及植物多样性特征指数均优于半阳坡。掌握不同微地形植被配置的差异,有助于提高陕北黄土区植被恢复措施的有效性和持续性。

关键词:微地形; 物种组成; 草本生物量; 植被盖度; 植物多样性; Margalef指数; Pielou指数; Shannon-Wiener指数; Simpson指数

陕北黄土区长年干旱少雨,地形复杂、地貌破碎,水土流失严重,生态环境脆弱,该区的植被恢复重建问题变得至关重要[1-2]。陕北黄土区坡面在土壤侵蚀等作用下形成切沟、浅沟、塌陷、陡坎和缓台等大小不同、形状各异的微地形[3-4],这些微地形使坡面变得凹凸不平,影响土壤水分、养分等植物生境条件的空间再分配[5-7],而土壤水分、养分的分布差别可能导致不同微地形及原状坡的植物群落特征产生显著差异[8]。在陕北黄土区的植被恢复建设中,忽略微环境的差异可能导致植被成活率和保存率低等问题[9],微地形已成为影响植物群落结构配置的关键因素[3];因此,研究不同微地形植被特征,掌握不同微地形植被配置的差异,有助于提高陕北黄土区植被恢复措施的有效性和持续性。

国内外已有不少关于微地形植被的研究,国外研究[10-13]主要集中于微地形对树木的物种组成、个体大小、林分结构和分布格局等方面的影响 。国内关于微地形植被的研究,主要集中于微地形对天然林的生长状况和群落结构的影响[14-18];但关于陕北黄土区不同坡向各类微地形之间的植被特征对比分析却鲜有报道。本文通过对比分析不同坡向及同一坡向各类微地形上植物群落的物种组成、数量特征以及植物多样性特征,揭示陕北黄土区不同微地形植被特征及其与原状坡的差异,以期为陕北黄土区的植被恢复建设提供参考。

1研究区概况

吴起县位于延安市西北部,地处E 107°38′57″~108°32′49″,N 36°33′33″~37°24′27″,海拔介于1 233~1 809 m之间,属于典型的黄土高原丘陵沟壑区。该县属于暖温带大陆性干旱季风气候,年平均气温7.8 ℃,无霜期96~146 d,年平均陆地蒸发量为400~450 mm,年平均降水量为478.3 mm,7—9月降水量可占到全年降水量的62%以上,其他季节多为无效降水。土壤类型主要为黄绵土,质地为轻壤。合沟流域处于吴起县中部,自1998年初以来实施退耕还林(草)工程,完全依靠自然恢复,目前坡面植被以草本群落为主,零星分布着小灌木和乔木幼苗。

2研究方法

2.1样地调查

于2014年7—8月,调查研究区内微地形的分布情况,以半阳坡向和半阴坡向梁峁坡部位的微地形作为研究样地。每个坡向至少取5个微地形样地,并设置3个5 m×5 m的原状坡样地为对照组,在各个样地内按照机械设置方法取3个1 m×1 m的草本样方;若出现小灌木或乔木幼苗,则根据实际情况将样方面积适当扩大。其中浅沟和切沟的样方设置在其底部,共调查57个草本样方。调查样方内植物的种类及其株数、平均高度,采用目视判读法估计植物种盖度和样方总盖度,称取地上植物鲜重,采用烘干称量法获取生物量和干鲜比。如若出现小灌木或乔木幼苗,则记录其种类及其株数、树高和冠幅。同时记录每个样地的坡向、坡位、坡度、海拔以及经纬度。

2.2数据处理

采用重要值测定群落物种组成,用以划定群落的优势种;选用Margalef指数、Pielou指数、Shannon-Wiener指数以及Simpson指数对比分析不同坡向不同微地形的植物群落多样性特征。各指数的计算公式见参考文献[19-21]。

对陕北黄土区植被的草本生物量、盖度以及植物多样性指数与地形因子进行相关分析。对微地形类型、坡向、坡位和坡度等4个地形因子进行分级量化。其中,微地形类型按照土壤水分从小到大[8]顺序赋值为:陡坎=1,浅沟=2,缓台=3,切沟=4,塌陷=5;坡向赋值为:半阳坡=1,半阴坡=2;坡位赋值为:梁峁坡上部=1,梁峁坡中部=2,梁峁坡下部=3。

在Excel软件中完成植物群落的相关计算,在SPSS 18.0软件中完成双变量相关分析。

3结果与分析

3.1微地形植被特征与地形因子的相关性

由表1可知,植物群落的草本生物量、盖度以及各植物多样性指数与微地形类型、坡向均存在较大的相关关系,其中微地形与生物量、丰富度指数呈极显著相关(P<0.01),坡向与Simpson指数、Pielou指数呈极显著相关(P<0.01)。坡位仅和生物量呈显著相关(P<0.05),坡度和各项植物群落特征指数的相关性不显著。由此可见,微地形类型和坡向与生物量、盖度以及各植物多样性指数密切相关,对陕北黄土区植被特征具有重要影响。

表1 植被特征与地形因子的相关性

注:n为样方数;*表示显著性水平在0.05以内,即显著相关;**表示显著性水平在0.01以内,即极显著相关。Note:The sample of * indicates a significant correlation whileP<0.05; the sample of ** indicates an extremely significant correlation whileP<0.01;n=No. of plots.

3.2微地形植物群落物种组成特征

由表2可知,半阴坡各类微地形的植物群落物种数均高于半阳坡。在半阳坡内,塌陷出现乔木1种,为小叶杨(Populussimonii),灌木2种,为扁核木(Prinsepiautilis)和小叶锦鸡儿(Caraganamicrophylla);切沟出现乔木2种,为小叶杨和榆树(Ulmuspumila),灌木2种,为扁核木和互叶醉鱼草(Buddlejaalternifolia)。与半阳坡相比,半阴坡的陡坎出现三裂叶绣线菊(Spiraeatrilobata)的幼苗,切沟的灌木多出一种,为三裂叶绣线菊,塌陷的乔灌木物种组成与之相同。

由表3可知,半阳坡和半阴坡的植物群落物种组成均优于原状坡,其中半阳坡形成以星毛委陵菜(Potentillaacaulis)、赖草(Leymussecalinus)等多年生草本植物为优势种的植物群落,半阴坡形成以铁杆蒿(Artemisiasacrorum)、茭蒿(Artemisialeucophylla)等地带性多年生草本植物为优势种的植物群落,其植物群落所处的自然演替阶段较半阳坡高级。在半阳坡内,塌陷和切沟都出现灌木和乔木,缓台形成以多年生草本植物大针茅(Stipagrandis)、赖草为优势种的植物群落,陡坎和浅沟形成以一年生草本植物星毛委陵菜为优势种和以铁杆蒿、茭蒿等地带性多年生草本植物为伴生种的植物群落,依据秦伟等[22]对黄土区退耕地植被自然演替的研究,各类微地形植物群落所处的演替阶段排序为:塌陷、切沟>缓台>陡坎、浅沟。

在半阴坡内,塌陷和切沟同样出现灌木和乔木,浅沟形成以铁杆蒿为优势种的植物群落,缓台和原状坡形成以星毛委陵菜为优势种的植物群落,二者物种组成无明显区别,与半阳坡相比,各类微地形植物群落所处的演替阶段排序有所区别:塌陷、切沟>浅沟>缓台、陡坎。

表2 微地形植物群落构成统计

表3 地形植物群落主要物种

3.3微地形草本生物量和植被盖度分异

对比分析不同坡向不同微地形的植被盖度和草本生物量(图1和图2),半阳坡各类微地形的植被盖度均高于原状坡,其中切沟和塌陷差异最显著,除陡坎外,各类微地形的草本生物量均高于原状坡。陡坎的盖度高于原状坡,而生物量低于原状坡,这可能因为陡坎的坡度远大于原状坡,伴生种中存在长势较高的赖草,植被盖度指地上植被的投影面积占地面的比率,故陡坎的盖度高于原状坡而生物量低于原状坡。半阴坡各类微地形的植被盖度和草本生物量均高于半阳坡。在2个坡向内,切沟在植被盖度和生物量上的优势最突出,陡坎与原状坡无明显差异。

图1 不同微地形植被盖度Fig.1 Coverage of plant communities on micro-topography

图2 不同微地形草本生物量Fig.2 Biomass of plant communities on micro-topography

图3 不同坡向微地形植物群落多样性指数Fig.3 Diversity indices of plant communities on micro-topography in different slope aspects

3.4微地形植物多样性特征分异

由图3知,半阳坡与半阴坡各项植物多样性特征指数的大小顺序基本一致,均大于原状坡,但半阴坡的各项多样性特征指数波动幅度更大,说明在半阴坡向,植被特征受不同微地形类型的影响更加敏感;半阴坡各项植物多样性特征指数均大于半阳坡,说明半阴坡的土壤水分、养分以及光照等生态环境条件有利于植物的生长、发育和演替。

半阳坡内,丰富度指数从大到小排序为浅沟>切沟>缓台>塌陷>原状坡>陡坎,其中浅沟最大、陡坎最小,浅沟、切沟和缓台三者的丰富度无明显区别;均匀度指数从大到小排列为塌陷>切沟>缓台>陡坎>浅沟>原状坡;Shannon-Wiener指数从大到小排列为切沟>塌陷>缓台>浅沟>陡坎>原状坡,其中切沟最大,陡坎与原状坡无明显区别;Simpson指数的变化趋势与Shannon-Wiener指数基本一致,但切沟更为突出。

半阴坡内,物种丰富度指数大小排列与半阳坡基本一致,但陡坎要高于原状坡;均匀度指数从大到小排列为切沟>塌陷>缓台>浅沟>陡坎>原状坡;Shannon-Wiener指数与Simpson指数的大小排列与半阳坡均一致。

4讨论

微地形改变了降水在坡面上的再分配路径,造成土壤水分、养分以及光照等生境条件的空间差异,研究[8,23]显示,微地形土壤水分、养分及光照条件优于原状坡;因此,各类微地形植物群落的物种组成、植被盖度、草本生物量及植物多样性指标等多优于原状坡。除此之外,切沟由于其长度、宽度以及下切深度规模大,利于坡面径流的汇集和土壤养分、水分的保持[24],从而生物量、植被盖度相对较大,各项多样性指数高,在相同的自然恢复时间内,其灌木和乔木幼苗出现较早,因此切沟的植被状况最优。浅沟与切沟形状相似,但其长、宽、深的规模不大,保水保肥能力没有切沟好,缓台地势相对平缓、水分分布较均匀,因此浅沟和缓台植被状况较好。塌陷的Shannon-Wiener指数较高、陡坎的Shannon-Wiener指数较低,这与王晶等[9]研究结果不一致。塌陷除地形利于汇集上部坡面径流外,可能是因为研究区的塌陷本身面积相对大、发育比较完全,保水保养的能力好。同时也有研究[8,25]表明:各类微地形中塌陷的水分、养分等生境条件最优,而湿润的生态环境更有利于植被均匀分布,因此多样性指数较高;陡坎坡度大、地形陡,水分条件差,因此多样性指数较低、植被状况最差。

在陕北黄土区,水分是限制植被生长发育的关键因子,半阳坡较半阴坡相比,光照时间长、水分养分条件差[26];因此,半阴坡各类微地形的植物群落在物种组成、植被盖度、草本生物量及各项植物多样性指标等方面都明显优于半阳坡。除此之外,半阳坡形成以星毛委陵菜、赖草等多年生草本植物为优势种的植物群落,半阴坡形成以铁杆蒿、茭蒿等地带性多年生草本植物为优势种的植物群落,这与秦伟等[22,27-28]研究结果相符。半阴坡植物群落所处的自然演替阶段较半阳坡高级,说明土壤水分、养分条件优异的半阴坡植物群落的自然演替速度更快。

5结论

1)半阳坡和半阴坡各类微地形植物群落的物种组成、植被盖度、草本生物量及植物多样性指标等多优于原状坡,其中,出现灌木和乔木幼苗的切沟和塌陷的植被状况最优,其次为浅沟和缓台,陡坎最差。

2)半阴坡各类微地形的植物群落在物种组成、植被盖度、草本生物量及各项植物多样性指标等方面都明显优于半阳坡,其中,半阳坡形成了以星毛委陵菜、赖草等多年生草本植物为优势种的植物群落,半阴坡形成了以铁杆蒿、茭蒿等地带性多年生草本植物为优势种的植物群落。

3)陕北黄土区坡面分布的各类微地形使地貌变得破碎,各类微地形生境条件的差异导致植被特征之间存在显著差异,从而造成陕北黄土区植被片面化;因此,在陕北黄土区进行人工植被恢复建设时,除了遵循立地条件划分植被恢复单元的原则外,应考虑各类微地形自身的植物群落特征,从而提高人工植树造林生态恢复措施的有效性和持续性。在半阴坡可进行乔、灌、草复合配置,对于生态环境优异的切沟和塌陷可适当提高物种配置的栽植密度;而半阳坡主要以恢复和保护草本群落为主,仅在生态环境较好的切沟和塌陷进行草、灌复合配置。

6参考文献

[1]王延平, 邵明安. 陕北黄土丘陵沟壑区人工草地的土壤水分植被承载力[J]. 农业工程学报, 2012, 28(18):134.

Wang Yanping, Shao Mingan. Vegetation soil water carrying capacity of artificial pasture in loess region in Northern Shaanxi, China [J]. Transactions of the CSAE, 2012, 28(18):134. (in Chinese)

[2]李冬梅, 焦峰, 雷波, 等. 黄土丘陵区不同草本群落生物量与土壤水分的特征分析[J]. 中国水土保持科学, 2014, 12(1):33.

Li Dongmei, Jiao Feng, Lei Bo, et al. Aboveground biomass production and soil moisture characteristics of different herb communities in the loess hilly-gully region [J]. Science of Soil and Water Conservation, 2014, 12(1):33. (in Chinese)

[3]路保昌,薛智德,朱清科,等. 干旱阳坡半阳坡微地形土壤水分分布研究[J]. 水土保持通报, 2009, 29(1):62.

Lu Baochang, Xue Zhideng, Zhu Qingke, et al. Soil water in micro-terrain on sunny and semi-sunny slopes[J]. Bulletin of Soil and Water Conservation, 2009, 29(1):62. (in Chinese)

[4]邝高明, 朱清科, 赵磊磊, 等. 黄土丘陵沟壑区陡坡微地形分布研究[J]. 干旱区研究, 2012, 29(6): 1083.

Kuang Gaoming, Zhu Qingke, Zhao Leilei, et al.Study on distribution of microrelieves on steep slopes in a loess hilly-gully region[J]. Arid Zone Research, 2012, 29(6): 1083. (in Chinese)

[5]王延平, 邵明安, 张兴昌. 陕北黄土区陡坡地人工植被的土壤水分生态环境[J]. 生态学报, 2008, 28(8):3669.

Wang Yanping, Shao Mingan, Zhao Xingchang. Soil moisture ecological environment of artificial vegetations in steep slope of loess region in North Shaanxi Province[J]. Acta Ecologica Sinica, 2008, 28(8):3669. (in Chinese)

[6]张宏芝, 朱清科, 赵磊磊, 等. 陕北黄土坡面微地形化学性质[J]. 中国水土保持科学, 2011, 9(5):20.

Zhang Hongzhi, Zhu Qingke, Zhao Leilei, et al. Soil chemical properties of micro-topography on loess slope in Northern Shaanxi Province[J]. Science of Soil and Water Conservation, 2011, 9(5):20. (in Chinese)

[7]邝高明, 朱清科, 刘中奇, 等. 黄土丘陵沟壑区微地形对土壤水分及生物量的影响[J]. 水土保持研究, 2012, 19(3):74.

Kuang Gaoming, Zhu Qingke, Liu Zhongqi, et al. Effect of microrelief on the soil water and vegetation arrangement in loess hilly and gully region [J]. Research of Soil and Water Conservation, 2012, 19(3):74. (in Chinese)

[8]赵荟, 朱清科, 秦伟, 等. 黄土高原干旱阳坡微地形土壤水分特征研究[J]. 水土保持通报, 2010, 30(3):64.

Zhao Hui, Zhu Qingke, Qin Wei, et al. Soil moisture characteristics on microrelief of dry south-slope on the Loess Plateau[J]. Bulletin of Soil and Water Conservation, 2010, 30(3):64. (in Chinese)

[9]王晶, 朱清科, 秦伟, 等. 陕北黄土区封禁流域坡面微地形植被特征分异[J]. 应用生态学报, 2012, 23(3):694.

Wang Jing, Zhu Qingke, Qin Wei, et al. Differentiation of vegetation characteristics on slope micro-topography of fenced watershed in loess area of north Shaanxi Province, Northwest China[J]. Chinese Journal of Applied Ecology, 2012, 23(3):694. (in Chinese)

[10] Enoki T. Microtopography and distribution of canopy trees in a subtropical evergreen broad-leaved forest in the northern part of Okinawa Island, Japan [J]. Ecological Research, 2003,18(18):103.

[11] Nagamatsu D,Miura O. Soil disturbance regime in relation to micro-scale landforms and its effects on vegetation structure in a hilly area in Japan [J]. Plant Ecology, 1997, 133(2):191.

[12] Nagamatsu D, Hirabuki Y, Mochida Y. Influence of micro-landforms on forest structure, tree death and recruitment in a Japanese temperate mixed forest [J]. Ecological Research, 2003, 18(5):533.

[13] Koponen P, Nygren P, Sabatier D, et al. Tree species diversity and forest structure in relation to microtopography in a tropical freshwater swamp forest in French Guiana [J]. Plant Ecology, 2004, 173(1): 17.

[14] 赵维军, 张岩, 朱清科, 等. 陕北黄土坡面微地形对乔木生长特征的影响[J]. 应用基础与工程科学学报, 2014, 22(1):69.

Zhao Weijun, Zhang Yan, Zhu Qingke, et al. Effects of micro-topography on tree growth characteristics in loess slope of Northern Shaanxi[J]. Journal of Basic Science and Engineering, 2014, 22(1):69. (in Chinese)

[15] 马旭东, 张苏峻, 苏志尧, 等. 车八岭山地常绿阔叶林群落结构特征与微地形条件的关系[J]. 生态学报, 2010, 30(19):5151.

Ma Xudong, Zhang Sujun, Su Zhiyao, et al.Community structure in relation to microtopography in a montane evergreen broadleaved forest in Chebaling National Nature Reserve[J]. Acta Ecologica Sinica,2010, 30(19):5151. (in Chinese)

[16] 杨永川, 达良俊, 由文辉, 等. 浙江天童国家森林公园微地形与植被结构的关系[J]. 生态学报, 2005, 25(11):2830.

Yang Yongchuan, Da Liangjun, You Wenhui, et al. Vegetation structure in relation to micro-landform in Tiantong National Forest Park, Zhejiang, China[J]. Acta Ecologica Sinica, 2005, 25(11):2830. (in Chinese)

[17] 商侃侃, 达良俊. 孑遗落叶阔叶树种微地形空间分异格局及共存机制研究概述[J]. 生态学杂志, 2013, 32(6):1912.

Shang Kankan, Da Liangjun. Micro-topographic spatial differentiation pattern and coexistence mechanism of relict deciduous broadleaved trees: A review [J]. Chinese Journal of Ecology, 2013, 32(6):1912. (in Chinese)

[18] 何怀江, 张春雨, 赵秀海, 等. 吉林蛟河次生针阔混交林群落结构与微地形关系[J]. 东北林业大学学报, 2014, 42(5):13.

He Huaijiang, Zhang Chunyu, Zhao Xiuhai, et al. Associations between community structure and micro-topography in mixed broadleaf-conifer forest of Jiaohe, Jinlin Province[J]. Journal of Northeast Forestry University, 2014, 42(5):13. (in Chinese)

[19] 王倩, 艾应伟, 裴娟, 等. 遂渝铁路边坡草本植物多样性季节动态和空间分布特征[J]. 生态学报, 2010, 30(24):6892.

Wang Qian, Ai Yingwei, Pei Juan, et al. Seasonal dynamics and spatial distribution of herbage diversity on the slopes of Suiyu railway[J]. Acta Ecologica Sinica, 2010, 30(24):6892. (in Chinese)

[20] 奇凯, 张春雨, 侯继华, 等. 赤峰市沙地油松林草本植物多样性及种间关联动态[J]. 生态学报, 2010, 30(18):5106.

Qi Kai, Zhang Chunyu, Hou Jihua,et al. Dynamics of species diversity and interspecific associations of herbaceous plants in aPinustabulaeformisforest on a sandy site in Chifeng, China[J]. Acta Ecologica Sinica, 2010, 30(18):5106. (in Chinese)

[21] 李步杭, 张健, 姚晓琳, 等. 长白山阔叶红松林草本植物多样性季节动态及空间分布格局[J]. 应用生态学报, 2008, 19(3):467.

Li Buhang, Zhang Jian, Yao Xiaolin, et al. Seasonal dynamics and spatial distribution patterns of herbs diversity in broadleaved Korean pine (Pinuskoraiensis) mixed forest in Changbai Mountains[J]. Chinese Journal of Applied Ecology, 2008, 19(3):467. (in Chinese)

[22] 秦伟, 朱清科, 刘中奇, 等. 黄土丘陵沟壑区退耕地植被自然演替系列及其植物物种多样性特征[J]. 干旱区研究, 2008, 25(4):507.

Qin Wei, Zhu Qingke, Liu Zhongqi, et al. Study on natural series of vegetation and plant species diversity on returning land for farming to forests and grassplots in the hilly-gully regions of the Loess Plateau[J].Arid Zone Research, 2008, 25(4):507. (in Chinese)

[23] 王晶, 朱清科, 赵荟, 等. 陕北黄土区阳坡微地形土壤水分特征研究[J].水土保持通报, 2011, 31(4):16.

Wang Jing, Zhu Qingke, Zhao Hui, et al. Soil moisture characteristics of micro-topography in south slope of loess region in Northern Shaanxi Province [J]. Bulletin of Soil and Water Conservation, 2011, 31(4):16. (in Chinese)

[24] 张健, 刘国彬, 许明祥,等. 黄土丘陵区沟谷地植被恢复群落特征研究[J].草地学报, 2008, 16(5):485.

Zhang Jian, Liu Guobin, Xu Mingxiang, et al. Primary study on the community characteristics of vegetative restoration in the gully area of the hilly loess region[J]. Acta Agrestia Sinica, 2008, 16(5):485. (in Chinese)

[25] 张宏芝, 朱清科, 赵磊磊, 等. 陕北黄土坡面微地形土壤物理性质研究[J].水土保持通报, 2011, 31(6):55.

Zhang Hongzhi, Zhu Qingke, Zhao Leilei, et al. Soil physical properties of micro-topography on loess slope in North Shaanxi Province[J]. Bulletin of Soil and Water Conservation, 2011, 31(6):55. (in Chinese)

[26] 周萍, 刘国彬, 侯喜禄. 黄土丘陵区不同坡向及坡位草本群落生物量及多样性研究[J].中国水土保持科学, 2009, 7(1):67.

Zhou Ping, Liu Guobin, Hou Xilu, et al. Biomass and species diversity of herbosa at different position and aspects of slope in the hilly-gully region of Loess Plateau [J]. Science of Soil and Water Conservation, 2009, 7(1):67. (in Chinese)

[27] 秦伟, 朱清科, 张宇清, 等. 陕北黄土区生态修复过程中植物群落物种多样性变化[J].应用生态学报, 2009, 20(2):403.

Qin Wei, Zhu Qingke, Zhang Yuqing, et al. Dynamics of plant community species diversity in the process of ecological rehabilitation in north Shaanxi loess area[J]. Chinese Journal of Applied Ecology, 2009, 20(2):403. (in Chinese)

[28] 王国梁, 刘国彬, 刘芳, 等. 黄土沟壑区植被恢复过程中植物群落组成及结果变化[J].生态学报, 2009, 23(12):2550.

Wang Guobin, Liu Guobin, Liu Fang, et al. Changes in composition and structure of plant communities during the course of restoration at loess gully region[J].Acta Ecologica Sinica, 2009, 23(12):2550. (in Chinese)

(责任编辑:程云郭雪芳)

Response of vegetation characteristics to slope micro-topography in loess area of north Shaanxi Province

Lu Jiyuan, Zhu Qingke, Chen Wensi, Wang Yu

(Key Laboratory of Soil and Water Conservation & Desertification Combating, Ministry of Education, Beijing Forestry University,100083, Beijing, China)

Abstract:[Background] The objective of this study is to grasp the spatial differences of vegetation characteristics on 5 kinds of micro-topographies including gully, collapse, platform, shallow gully, and scarp in loess area of north Shaanxi Province. [Methods] Based on the investigation of undisturbed slope and the 5 different micro-topographies in semi-sunny and semi-shady slope of Hegou valley in Wuqi County of Shaanxi Province, the correlations between micro-topographies and vegetation characteristics of species composition, herbaceous biomass, vegetation coverage, and vegetation diversity were analyzed. The data processing methods of this paper were bivariate analysis and descriptive statistical analysis. [Results] The results revealed that: 1) The species composition, herbaceous biomass, vegetation coverage and vegetation diversity of plant communities on all kinds of micro-topographies were better than those on the undisturbed slope. At the same time, the vegetation condition on gully and collapse were the best, followed by shallow gully and platform, and the worst on the scarp. 2) The Simpson index and Shannon-Wiener index on different micro-topographies and undisturbed slope were in the order of gully > collapse > platform > shallow gully > scarp > undisturbed slope, and the stages of natural succession of the plant communities on gully and collapse were higher than other micro-topographies. 3) After 15 years of enclosure recovery, the plant community with Potentilla acaulis and Aneurolepidium dasystachys as the dominant species was formed on the semi-sunny slope, meanwhile, the plant community with Artemisia sacrorum and Artemisia giraldii as the dominant species was formed on semi-shady slope, and there was also a small amount of shrub and arbor in some areas. At the same time, the species composition, herbaceous biomass, coverage and vegetation diversity of plant communities on different micro-topographies of the semi-shady slope were all better than those in the semi-sunny slope. The spatial differences of physical and chemical properties in all kinds of micro-topographies resulted in vegetation characteristics different on the slope land in loess area of north Shaanxi Province. [Conclusions] In addition to follow the principle of the vegetation restoration units divided by site condition, the vegetation characteristics on different micro-topographies should be taken into consideration in the construction of artificial vegetation restoration in loess area of north Shaanxi Province. On the semi-shady slope land, the composite configuration of arbor, shrub and herb should be adopted, and the density of plant species may be increased on gully and collapse due to their favorable ecological condition. While on the semi-sunny slope land, the main content of the artificial vegetation restoration is to restore and protect the herbaceous community, moreover, the composite configuration of shrub and herb can be adopted on gully and collapse where ecological environment are better than other micro-topographies.

Keywords:micro-topography; species composition; herbaceous biomass; coverage; vegetation diversity; Margalef index; Pielou index; Shannon-Wiener index; Simpson index

收稿日期:2015-04-15修回日期: 2015-12-30

第一作者简介:卢纪元(1991—),女,硕士研究生。主要研究方向:林业生态工程。 E-mail:391883654@qq.com †通信 朱清科(1953—),男,教授,博士生导师。主要研究方向:林业生态工程。E-mail:zhuqingke@suho.com

中图分类号:Q948

文献标志码:A

文章编号:1672-3007(2016)01-0053-08

DOI:10.16843/j.sswc.2016.01.007

项目名称: 林业公益性行业科研专项经费课题“黄土丘陵严重侵蚀区植被恢复和重建技术研究”(201104002-2)

猜你喜欢
阴坡阳坡原状
北方干旱阳坡山地造林技术研究
山坡羊
基于细观结构的原状黄土动弹性模量和阻尼比试验研究
毓庆宫惇本殿明间原状陈列的复原
重现「皇太子之宫」 毓庆宫原状陈设复原记
不同坡向 坡位对祁连圆柏生长的影响
有关林线高低问题
原状黄土各向异性及卸载变形特征试验研究