封育对荒漠草原两种植物群落土壤种子库的影响

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李国旗, 邵文山, 赵盼盼, 靳长青. 封育对荒漠草原两种植物群落土壤种子库的影响. 草业学报, 2018,27(6): 52-61
LI Guo-qi, SHAO Wen-shan, ZHAO Pan-pan, JIN Chang-qing. Effects of enclosure on the soil seed bank of two plant communities on the desert steppe. Acta Prataculturae Sinica,2018,27(6): 52-61 复制到剪切板

Doi:10.11686/cyxb2017274
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封育对荒漠草原两种植物群落土壤种子库的影响

李国旗^1,², 邵文山^1,², 赵盼盼^1,², 靳长青^1,²

1.宁夏大学西北土地退化与生态恢复国家重点实验室培育基地,宁夏银川 750021

2.宁夏大学西北退化生态系统恢复与重建教育部重点实验室,宁夏银川 750021

作者简介:李国旗(1965-),男, 宁夏平罗人,研究员,博士。E-mail: guoqilee@163.com

收稿日期: 2017-06-13

基金项目:国家重点研发计划“矿区生态修复与生态安全保障技术集成示范研究(2017YFC0504406)”和国家自然科学基金“围封前后荒漠草原区土壤种子库特征与繁殖对策研究(31540007)”资助

摘要

土壤种子库作为植被的潜在种源,对荒漠草原植被恢复、群落演替具有重要的指示意义。以宁夏盐池县荒漠草原苦豆子群落和芨芨草群落为研究对象,在2种群落封育和未封育的草地上,选取地势相对平坦、环境条件较为一致的25 m×30 m 的4个大的样方进行群落调查;并在4个大的样方内取0~2 cm、2~5 cm和5~10 cm土层的土样,采取种子过筛直接辨认和种子萌发试验来进行土壤种子库的鉴定。分析了两种植物群落封育前后土壤种子库物种组成、种子密度、多样性及相似性等特征。结果表明:封育可提高两种植物群落土壤种子库中物种数目;而对两种植物群落土壤种子库种子密度的影响不同,苦豆子群落种子密度封育内外差异较小,芨芨草群落封育内种子密度显著提高。随着土层的加深,两种植物群落封育内外土壤种子库物种数和种子密度均呈递减趋势,封育后两种植物群落不同土层物种数均有增加,但封育对两种植物群落土壤种子库中种子密度的垂直分布影响不同。封育可提高两种植物群落土壤种子库的多样性、均匀度和丰富度,但两种植物群落土壤种子库的多样性特征对封育的响应不同,芨芨草群落在荒漠草原的稳定性更高。两种植物群落封育内外土壤种子库相似性相对较高,苦豆子群落封育后有向芨芨草群落演替的趋势。

关键词: 土壤种子库; 苦豆子群落; 芨芨草群落; 荒漠草原; 封育

Effects of enclosure on the soil seed bank of two plant communities on the desert steppe

LI Guo-qi^1,², SHAO Wen-shan^1,², ZHAO Pan-pan^1,², JIN Chang-qing^1,²

1.Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China, Ningxia University, Yinchuan 750021, China

2.Key Laboratory for Recovery and Restoration of Degraded Ecosystem in North-western China of Ministry of Education, Ningxia University, Yinchuan 750021, China

Abstract

The soil seed bank (SSB), as a potential source of vegetation, has significance for vegetation restoration and community succession on the desert steppe. In this study, we analyzed the SSB of two plant communities ( Sophora alopecuroides and Achnatherum splendens communities), fenced and unfenced, on the desert steppe in Yanchi County, Ningxia Province. Four relatively even and flat quadrats (25 m×30 m each) of S. alopecuroides and A. splendens communities, fenced and unfenced, were selected for these analyses. The soil samples from the four quadrats were separated into three layers (0-2 cm, 2-5 cm, and 5-10 cm) and sieved, and then the species of the seeds in the SSB were identified by direct observations and then by germination tests. We compared the characteristics of two communities (SSB species composition, seed density, diversity, and similarity) between fenced (enclosed) and unfenced conditions. The results showed that: 1) Enclosure increased the number of species in the SSB in both communities, but its effects on seed density in the SSB differed between the two communities. The seed density of the S. alopecuroides community SSB was slightly different between the fenced and unfenced areas, while that of the A. splendens community SSB was markedly higher inside the fenced area. 2) The number of species in the SSB and the seed density tended to decrease with increasing soil depth in both communities, inside and outside the fence. Although the number of species in different soil layers was greater in the fenced area for both communities, the effect of enclosure on the vertical distribution of seed density in the SSB differed between the two communities. 3) The diversity, evenness, and abundance of the SSB were greater inside the fenced area than outside the fenced area for both communities, but the effects of enclosure on SSB diversity differed between the two communities. The S. alopecuroides community was more stable than the A. splendens community on the desert steppe. 4) The SSBs of the two communities showed relatively high similarity, and there was a trend towards succession of the S. alopecuroides community to the A. splendens community after enclosure.

Keyword: soil seed bank (SSB); community of Sophora alopecuroides; community of Achnatherum splendens; desert steppe; fence

文章图片

土壤种子库作为植被种群生活史的一个阶段, 在植被更新与恢复、生物多样性维护、植被演替和扩散过程中有着不可低估的作用^{[1, 2]}。土壤种子库在植被经历干扰后是其恢复的主要种源, 在退化草地的恢复与重建中承担着重要的角色, 而且能够反映种群对环境变化的响应^[3]。植被演替的过程不仅包括地上植被组成与结构的变化, 同时也包括土壤种子库的数量与格局的变化^[4]。荒漠草原生态系统是草原生态系统向荒漠生态系统过渡的一个最干旱的草原生态系统类型; 随着全球气候变化、人为开发过度等因素, 作为我国草原生态系统的重要组成部分的荒漠草原, 目前也承受着巨大的压力^{[5, 6]}。宁夏草地面积约为300万hm²左右, 其中荒漠草原的面积超过了近一半; 而宁夏盐池县地处典型的农牧交错带, 县境由东南至西北为广阔的干草原和荒漠草原, 生态系统十分脆弱, 特别是在近几十年来, 由于自然因素及人类活动干扰等因素, 草原植被退化、沙化非常严重。自2000年以来, 宁夏在全区范围内实施了以封育禁牧为主的一系列生态保育措施, 已经取得了一定的成效。由于荒漠草原是宁夏草原的主体类型, 因此宁夏退牧还草的效果也主要取决于荒漠草原的恢复程度^[7]。

苦豆子(Sophora alopecuroides)是一种多年生豆科草本植物, 茎直立, 奇数羽状复叶, 总状花序顶生, 荚果串珠状, 具多数卵球形种子。芨芨草(Achnatherum splendens)是一种多年生禾本科草本植物, 须根粗壮具沙套, 秆直立, 圆锥花序开展, 花果期6-9月。所选的苦豆子群落中出现了15种植物, 隶属于9科15属, 其中以禾本科的居多, 有5种; 在芨芨草群落中出现的植物有14种, 隶属于7科11属, 其中菊科有4种, 禾本科和藜科各有3种。苦豆子群落土壤容重较低, 土壤全氮含量相对较高; 芨芨草群落土壤pH明显较高, 土壤有机碳含量相对较高。苦豆子和芨芨草群落的土壤磷酸酶活性较高, 而蔗糖酶活性普遍较低^[8]。苦豆子和芨芨草是宁夏盐池县荒漠草原极端盐渍化生境的代表性植物, 研究这两种植物群落封育前后土壤种子库的变化特征, 为封育禁牧措施的评价和荒漠草原极端生境中植物群落恢复潜力的评估提供了参考依据。

1 材料与方法

1.1 研究区概况

研究区位于宁夏盐池县沙边子(E 107° 24', N 37° 43')地区, 属于典型的荒漠草原区, 是陕、甘、宁、蒙4省(区)的交界地带, 地处毛乌素沙地西南边缘处, 海拔1300~1370 m, 自然条件较为恶劣, 属于典型的中温带大陆性气候, 年降水量250 mm左右, 且主要集中在6-9月, 潜在年蒸发量达2500 mm左右, 年平均气温7.7 ℃, 年均无霜期165 d。地形主要为缓坡丘陵, 土壤类型主要为灰钙土、风沙土等, 土壤质地以风沙土为主^[8]。研究区封育植被主要有苦豆子、芨芨草、盐爪爪(Kalidium foliatum)、白刺(Nitraria tangutorum)和黑沙蒿(Artermisia ordosica)等。

1.2 研究方法

1.2.1 样地选择试验样地位于盐池县沙边子试验站。该样地自2000年围栏封育后, 一直未曾放牧。于2015年7月, 选取围栏封育内外苦豆子群落和芨芨草群落类型草地(表1), 在每块样地分别选取地势相对平坦、环境条件较为一致的25 m× 30 m的4个大的样方, 在每个大样方内布设5条“ 之” 字形样线, 每条样线间距5 m, 每条样线上距5 m取1个1 m × 1 m的样方, 每条样线上取6个样方, 共计120个样方进行植被调查。

表1 样地基本特征 Table 1 Main features of sampling plots

1.2.2 取样与试验处理于2016年3月在植被调查的4块大样方内, 各随机选择1 m× 1 m的小样方10块, 用20 cm× 20 cm× 10 cm的取土器, 分别取0~2 cm、2~5 cm、5~10 cm土层的土, 将同一大样方内所取的2份土样均匀混合在一起, 共计60个土样, 带回实验室自然风干, 过筛, 进行种子萌发试验。本试验中种子库的鉴定主要采取种子过筛直接辨认和种子萌发试验鉴定^[9]。其中种子辨认鉴定主要是肉眼可见部分种子, 即通过与已知种子对比进行辨认; 种子萌发是本试验种子库鉴定的主要方式, 即用无种子的毛细沙做基质置于花盆(大小:42 cm× 28 cm× 15 cm)底部(120 ℃高温处理), 约10 cm, 再将土样过筛去除杂物后均匀平铺在萌发用的花盆中(土层1~2 cm), 萌发时间为2016年5到9月, 开始萌发后可辨认的幼苗鉴定后去除, 无法辨认的继续生长直至鉴定出, 萌发2个月翻动土样, 至9月连续4周没有幼苗萌发, 结束试验。

1.3 计算方法

将鉴定的土壤种子数量换算成1 m²种子数量^[10], 根据土壤种子库物种和种子密度计算Shannon-Wiener多样性指数、Simpson 多样性指数、Pielou均匀度指数、Margalef丰富度指数^{[11, 12]}。

Shannon-Wiener多样性指数: $H = - \overset{S}{\sum_{i = 1}} (P_{i} \ln P_{i})$

Simpson 多样性指数: $D = 1 - \overset{S}{\sum_{i = 1}} (P_{i})^{2}$

Pielou均匀度指数:E=H/ln S

Margalef丰富度指数:M=(S-1)/ln N

式中:N为物种的个体总数; S为物种数目; P_i为第i个物种占总物种数的比例。

采用Sorensen相似性系数计算土壤种子库封育内外群落组成的相似性^[13]。

S_c=2w/(a+b)

式中:S_c为相似性系数; w为样地共有植物种数; a和b为两样地各自拥有的植物种数。

1.4 数据处理

用Excel 2007和SPSS 17.0进行数据统计和部分图表制作, 用LSD最小显著差法进行显著性分析。

2 结果与分析

2.1 封育内外土壤种子库的物种组成

由表2可知, 2种植物群落封育内外土壤种子库物种组成、同一物种密度组成均存在差异。苦豆子群落封育内土壤种子库中有23种物种, 种子密度达4550粒· m^-2, 隶属于5科19属, 其中禾本科和藜科物种数占主要优势, 分别达到39.13%和30.43%, 种子密度分别占32.42%和36.59%, 地上优势种苦豆子在土壤种子库中密度为525粒· m^-2, 占种子密度的11.54%。苦豆子群落封育外土壤种子库中存在19种物种, 种子密度为4710粒· m^-2, 隶属于6科16属, 禾本科植物种数下降仅有3种, 种子密度为17.62%, 藜科植物种数占优势达31.58%, 其种子密度占28.45%, 菊科植物有增加趋势, 其种子密度占到28.13%, 出现蒺藜科、萝藦科植物种, 苦豆子种子比例下降。芨芨草群落封育内土壤种子库植物种有29种, 种子密度达5350粒· m^-2, 隶属于9科24属, 其中菊科、藜科、禾本科植物种较多, 占总物种数的65.52%, 种子密度达到80.09%, 地上优势种芨芨草在土壤种子库中仅占4.32%。芨芨草群落封育外土壤种子库中物种数有26种, 种子密度为4285粒· m^-2, 隶属于8科22属, 菊科、藜科、禾本科仍为土壤种子库的主要物种, 占到69.23%, 种子密度达到80.86%, 旋花科、远志科植物消失, 新增加大戟科地锦植物种, 地上优势种芨芨草种子比例变化不大。

表2 不同植物群落围栏内外土壤种子库物种组成及其密度 Table 2 Species composition and density of SSB in different plant communities within and outside the fence

2.2 土壤种子库垂直分布格局

封育对2种植物群落土壤种子库的垂直分布产生了一定的影响(图1)。封育后2种植物群落土壤种子库不同土层物种数均呈增加趋势; 而随着土层深度的增加, 物种数逐渐下降。此外, 芨芨草群落封育内外土壤种子库物种数均高于苦豆子群落封育内外土壤种子库物种数。封育不仅对2种植物群落封育内外土壤种子库物种数在垂直分布上产生了影响, 对土壤种子库数量在垂直分布上也产生了影响。由表3 可知, 封育对2种植物群落土壤种子库数量影响不同, 2种植物群落封育内外随着土层的加深, 土壤种子库数量均呈下降趋势, 苦豆子群落土壤种子库种子数量总体上未封育种子数量高于封育内土壤种子库, 而芨芨草群落中则反之; 但封育对2种群落不同土层土壤种子数量分布的影响有所差异, 表层土(0~2 cm)中2种植物群落封育内土壤种子库种子数量均高于未封育土壤种子库, 而苦豆子群落中亚表层(2~5 cm)和深层土(5~10 cm)中未封育土壤种子库中种子数高于封育土壤种子库中的种子数, 芨芨草群落封育内外土壤亚表层和深层中土壤种子库种子数量分布特征与苦豆子群落中相反。

	Figure Option View Download New Window
	图1 不同土层不同植物群落土壤种子库的物种数Fig.1 Species number of SSB of different communities in different soil layer

表3 不同植物群落土壤种子库数量垂直分布格局 Table 3 Vertical distribution pattern of SSB amount in different communities (粒Grains· m^-2)

2.3 土壤种子库多样性分析

由表4可知, 封育内2种植物群落土壤种子库多样性、均匀度和丰富度指数均高于封育外, 说明围栏封育可提高植物群落土壤种子库的多样性、均匀度和丰富度。芨芨草群落封育内外土壤种子库多样性、均匀度和丰富度指数均分别高于苦豆子群落土壤种子库, 说明芨芨草群落可能在研究区的适应度相对更高。此外, 芨芨草群落封育外土壤种子库的Margalef丰富度指数高于苦豆子群落封育内, 但其Shannon-Wiener 多样性指数、Simpson 多样性指数和Pielou 均匀度指数低于苦豆子群落封育内, 说明苦豆子群落封育后土壤种子库的多样性、均匀度明显增加, 其丰富度虽有所增加但在一定时间内增加范围有限, 可能与群落生存生境本身有关。

表4 不同群落土壤种子库多样性、均匀度和丰富度指数 Table 4 Indexes of diversity, richness and pielou of the SSB in different communities

2.4 土壤种子库相似性分析

由表5可知, 封育对群落土壤种子库相似性变化有影响, 且对不同植物群落土壤种子库相似性的变化影响不同。芨芨草群落封育内外间土壤种子库相似性最高, 但苦豆子群落封育内外土壤种子库相似性低于苦豆子群落封育内与芨芨草群落封育外间的相似性, 说明不同植物群落土壤种子库对封育措施的响应有所差异, 芨芨草群落封育后相似性明显提高, 苦豆子群落对封育的响应程度并不高。芨芨草群落封育内土壤种子库与苦豆子群落封育内外土壤种子库相似性均相对较低, 低于封育外土壤种子库与苦豆子群落封育内外土壤种子库的相似性, 这一方面反映出苦豆子群落在荒漠草原退化中要早于芨芨草群落出现, 另一方面在植被恢复中, 苦豆子群落有向芨芨草群落演替的趋势。

表5 不同群落土壤种子库相似性分析 Table 5 Similarity analysis of SSB in different communities

3 讨论

3.1 封育内外土壤种子库的物种组成

不同草地类型的土壤种子库差异较大, 用不同的研究方法也会导致研究结果的不同^{[1, 14]}。Silvertown^[15]研究表明草地土壤种子库的范围在10³~10⁶粒· m^-2, 本试验中土壤种子库的规模符合Silvertown^[15]的研究结果。封育3年的高寒草地群落, 封育内外3种高寒草地群落土壤种子库物种数目差异不显著, 不同草地类型封育内外土壤种子库密度变化不同^[1]。还有研究结果认为退化样地土壤种子库种子密度显著高于封育样地^[16]。目前有关荒漠草原上土壤种子库对封育措施的响应研究较少。本研究发现封育措施提高了2种植物群落中的物种数目; 苦豆子群落封育内土壤种子密度低于封育外, 但差异不大, 芨芨草群落封育内土壤种子密度明显高于封育外, 说明荒漠草原不同植物群落土壤种子库物种数目及种子密度对封育措施的响应不同, 这和在高寒草地的研究结果类似, 可能一方面与地上植物的繁殖策略不同及土壤本身特性不同有关, 另一方面可能还与封育年限、研究方法不同有关, 有关这方面的研究还需要进一步验证。此外, 本研究中, 苦豆子群落封育内外土壤种子库中藜科植物物种数比例均较高, 封育后禾本科植物明显增加, 菊科植物减少, 蒺藜科、萝藦科植物消失; 芨芨草群落封育内外土壤种子库中藜科、禾本科、菊科植物种均占优势, 封育后旋花科、远志科植物出现, 大戟科植物消失, 说明封育改变了土壤种子库中潜在植物种群的结构。

3.2 土壤种子库垂直分布格局

土壤种子库具有明显的垂直分布格局, 这种立体结构影响着种子库种子的萌发和留存, 进而影响着未来植被的恢复与重建^[17]。Bekker等^[18]提出在没有遭到破坏的土壤生境中, 0~5 cm土壤层中的种子垂直分布符合一定的数学模型, 有研究表明^[19]土壤种子在土壤层中呈二项式分布或泊松分布。本研究中随着土层的加深, 2种植物群落封育内外土壤种子库中种子数量和物种数均呈递减趋势, 且种子数量递减显著(P< 0.05), 这与大多数的研究结果一致^{[17, 20, 21, 22]}; 封育后2种植物群落不同土层物种数均有增加, 说明封育一定程度上可增加群落物种, 但具体封育时间与不同群落土壤种子库中物种数量的变化关系还需要进一步研究。此外本研究中, 芨芨草群落封育后土壤种子库各土层种子数量均增加, 说明封育可提高种子数量; 但在苦豆子群落土壤种子库中土壤表层和深层封育内反而低于封育外, 可能是因为封育后下层土壤生境改善有利于种子的萌发, 也可能是封育后干扰减少, 种子储藏在土壤表层; 封育对2种群落土壤种子库数量的垂直分布影响不同, 说明封育对不同植物群落土壤种子库的影响不同, 可能一方面与地上植被种子大小、繁殖策略等有关, 另一方面封育后土壤生境有变化影响了种子的萌发与储藏。

3.3 土壤种子库多样性分析

本研究表明, 围栏封育可增加不同植物群落土壤种子库的多样性、均匀度和丰富度, 这与有关封育对土壤种子库影响的研究结果相一致^{[16, 23, 24]}, 有学者对典型草原封育过程中土壤种子库的变化进行了研究, 结果表明土壤种子库多样性和物种丰富度变化与封育年限有关^[25]; 而在高寒草地, 封育3年的3种群落土壤种子库在封育后围栏内外多样性、物种丰富度、均匀度变化不同^[1]。本试验中, 2种植物群落封育后土壤种子库多样性、均匀度及丰富度虽然均增加, 但不同植物群落对封育的响应有所差异, 2种植物群落围栏内外多样性特征的不同, 芨芨草群落在荒漠草原的稳定性更高, 而具体有关封育年限对不同植物群落土壤种子库的多样性特征影响还需要进一步研究。

3.4 土壤种子库相似性分析

群落相似性可以在一定程度上表征群落间相互关系, 其研究对群落替换、群落演替具有重要意义。本研究中, 2种植物群落封育内外土壤种子库间的相似性相对较高, 一方面荒漠草原植物种本身相对较少, 大多是适应度较高的植物种, 有关苦豆子和芨芨草作为伴生群落的研究也有报道^{[26, 27]}; 另一方面与种子传播有关, 荒漠草原自然条件更有利于种子的水平传播。不同植物群落封育内外相似性不同, 说明封育对不同植物群落土壤种子库的影响不同。此外本研究中, 苦豆子群落封育内与芨芨草群落封育外土壤种子库间的相似度较高, 说明苦豆子群落封育后有向芨芨草群落演替的趋势。

4 结论

主要研究了围封内外苦豆子群落和芨芨草两种植物群落的土壤种子库物种组成、种子密度、多样性及相似性等特征。初步结论如下:(1)封育可提高两种植物群落土壤种子库中物种数目, 且苦豆子群落无论是围封还是未围封样地, 其土壤种子库物种数均比芨芨草群落的多; (2)围封对两种植物群落土壤种子库种子密度的影响不同, 封育内外苦豆子群落种子密度变化较小, 但封育能显著提高外芨芨草群落种子密度; (3)随着土层的加深, 两种植物群落封育内外土壤种子库种子密度均呈递减趋势, 且表层土壤(0~2 cm)的种子密度均显著高较深的2个土层; (4)封育可提高两种植物群落土壤种子库的多样性、均匀度和丰富度。两种植物群落封育内外土壤种子库相似性相对较高, 苦豆子群落封育后有向芨芨草群落演替的趋势。

The authors have declared that no competing interests exist.

参考文献

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2012

0.0

. 2012, 21(5):23-31 DOI:doi:10.11686/cyxb20120503

Effect of 3-year fencing on soil seed banks of three alpine grassland communities

封育三年对三种高寒草地群落土壤种子库的影响

Deng B , Ren G H , Liu Z Y

邓斌, 任国华, 刘志云

选择青藏高原黄河源区封育三年的灌丛草地、小嵩草退化草地和黑土滩等３个高寒草地群落为研究对象，利用镜检法，对其土壤种子库的规模、物种组成、空间分布及与地上植被的相关性进行研究。结果表明，１）小嵩草退化草地、黑土滩、灌丛草地围栏内外土壤种子库密度分别为（９９３８±１７８０）粒／ｍ２和（１５３３０±１８２７）粒／ｍ２、（４０７４±４５９）粒／ｍ２和（３６４０±４８６）粒／ｍ２、（９８７９±１４５３）粒／ｍ２和（１２８９９±１６９５）粒／ｍ２，且只有小嵩草退化草地围栏内外表现出差异显著。２）３种高寒草地群落围栏内外土壤种子库物种数目差异不显著，但禾本科与莎草科种子在土壤种子库中所占的比例表现为围栏内＞围栏外，草地围栏能提高原生植被土壤种子库比例。３）各样地的土壤种子库的Ｓｈａｎｎｏｎ－Ｗｉｅｎｅｒ多样性指数、Ｓｉｍｐｓｏｎ多样性指数和Ｐｉｅｌｏｕ均匀度指数有着相同的变化规律：黑土滩＞灌丛草地＞小嵩草退化草地；Ｍａｒｇａｌｅｆ丰富度规律为：小嵩草退化草地＞黑土滩＞灌丛草地。３种高寒草地群落土壤种子库与地上植被的Ｓｏｒｅｎｓｅｎ相似性指数大小范围为０．３２～０．６４，变化为：黑土滩＞小嵩草退化草地＞灌丛草地，围栏内＞围栏外。４）土壤种子库主要集中在０～５ｃｍ土层中，平均占土壤种子库的比例为８８．５６％。黑土滩群落围栏内外５～１０ｃｍ层土壤种子库种子数所占的比例要显著大于灌丛草地与小嵩草退化草地。围栏封育能够提高退化高寒草地土壤种子库数量，对退化草地的恢复有重要作用。

... 土壤种子库作为植被种群生活史的一个阶段,在植被更新与恢复、生物多样性维护、植被演替和扩散过程中有着不可低估的作用^[1,2] ...

... 1 封育内外土壤种子库的物种组成不同草地类型的土壤种子库差异较大,用不同的研究方法也会导致研究结果的不同^[1,14] ...

... 封育3年的高寒草地群落,封育内外3种高寒草地群落土壤种子库物种数目差异不显著,不同草地类型封育内外土壤种子库密度变化不同^[1] ...

... 而在高寒草地,封育3年的3种群落土壤种子库在封育后围栏内外多样性、物种丰富度、均匀度变化不同^[1] ...

2014

0.0

. 2014, 34(11):2324-2330 DOI:doi:10.7606/j.issn.1000-4025.2014.11.2324

Soil seed bank properties under different land used models on sloping land with purple soils in Hengyang of Hunan Province, south central China

衡阳紫色土丘陵坡地不同土地利用模式下土壤种子库特征

Yang N , Fu M Y , Yang M Y

杨宁, 付美云, 杨满元

The sloping-land with purple soils in Hengyang of Hunan Province,South-central China covers 1.625×10 5 hm 2 .It is the most severe region of eco-environment,and at the same time,the most representative eco-catastropie region in South China.Therefore,ecosystem restoration of the present problem area has been focused.Since,re-vegetation is the first of any restoration program conducted,by which,land cover will be safe for further wastage.Thus,to comprehend the soil seed bank properties under different soil-used models,we investigated the soil seed bank in hill closing(20 a)(Ⅰ),abandoned farmland(2 a)(Ⅱ) and farmland(Ⅲ),using the “seed germination” method.The objectives of the present study were:How land-used influences the species composition in the ecosystem?What relationship exists between soil seed banks and re-vegetation?Results indicated:(1)The average seed density among three different land-used models were followed the order as model Ⅱ＞model Ⅲ＞model Ⅰ.(2)The effect of soil depth on seed number was significantly different as the highest seed number was found in 0～5 cm soil layer and showed decreasing trend with the increase of soil depth.(3)The Czekanowski similarity indices of three different land-used models seed banks were low(0～0.399 8).Patrick richness( R ) among three different land-used models were followed the order as model Ⅱ(16)＞model Ⅰ(14)＞model Ⅲ(13)( P ＞0.05),the Shannon-Wiener indices( H ) and Pielou evenness indices( E ),model Ⅱ＞model Ⅲ＞model Ⅰ( P ＜0.05),the Simpson indices( D ),model Ⅰ＞model Ⅲ＞model Ⅱ( P ＜0.05).(4)Most abundant herbaceous species composition was the member of Compositae and Gramineae family indicated the re-vegetation laid early stage of primary succession.(5)Model Ⅰ and model Ⅱ belonged to progressive succession(model Ⅰ stayed higher succession stages),and model Ⅲ,retrogressive succession.All the results indicated it was possible but difficult for ecosystem restoration only by soil seed bank in the area.Based on the consideration of natural re-vegetation potential,artificial restoration strategy in combination with natural re-vegetation should be employed,to accelerate the re-vegetation for a sustainable and healthy ecosystem on sloping-land with purple soils in Hengyang of Hunan Province,South-central China.

为了解衡阳紫色土丘陵坡地不同土地利用模式下土壤种子库特征,利用土壤种子库“萌发法”,对衡阳紫色土丘陵坡地种子库在封山育林(20 a)模式 (Ⅰ)、退耕还林(2 a)模式 (Ⅱ)、农耕模式(Ⅲ)的土壤种子库进行分析。结果表明:(1) 3种土地利用模式种子库平均密度的大小顺序为:模式Ⅱ＞模式Ⅲ＞模式Ⅰ。(2) 土壤种子集中分布于0～5 cm土层,随土层深度增加,种子数量与种类趋于减少。(3)3种土地利用模式种子库物种Czekanowski相似性系数( CC )较低,Patrick丰富度指数( R )的大小顺序为:模式Ⅱ＞模式Ⅰ＞模式Ⅲ( P ＞0.05);Shannon-Wiener指数( H )和Pielou均匀度指数( E )的大小顺序均为:模式Ⅱ＞模式Ⅲ＞模式Ⅰ( P ＜0.05);Simpson指数( D )的大小顺序为:模式Ⅰ＞模式Ⅲ＞模式Ⅱ( P ＜0.05)。(4)土壤种子库所含物种数较接近,物种组成以草本植物为主,菊科、禾本科占优势。(5)封山育林模式和退耕还林模式属于进展演替,封山育林模式处于较高演替阶段,农耕模式属于逆行演替。研究表明:衡阳紫色土丘陵坡地具有依靠土壤种子库实现自然恢复的潜力,但单依靠土壤种子库自然恢复到现存植被是困难的,需要在自然恢复潜力评估的基础上积极充分采取人工促进自然恢复的策略,促进当地的植被恢复。

... 土壤种子库作为植被种群生活史的一个阶段,在植被更新与恢复、生物多样性维护、植被演替和扩散过程中有着不可低估的作用^[1,2] ...

2003

0.0

. 2003, 25(5):15-22 DOI:doi:10.3321/j.issn:1673-5021.2003.05.003

Influence of fencing on degraded Kobresia humilis meadows and nondegraded

封育措施对退化与未退化矮嵩草草甸的影响

Zhou H K , Zhou L , Liu W

周华坤, 周立, 刘伟

摘　要：连续5年的封育处理对退化与未退化矮嵩草草甸产生了影响.研究表明,除了退化矮嵩草草甸内的均匀度指数下降不显著外,封育使两种矮嵩草草甸样地内的丰富度指数、多样性指数和均匀度指数下降都达显著水平.两种矮嵩草草甸的上下层高度均增加,其中未退化矮嵩草草甸增加显著,退化矮嵩草草甸增加不显著.两种矮嵩草草甸的枯草盖度增加显著,绿草盖度减少显著,各种群特征发生了有规律的消长.未退化矮嵩草草甸的莎草和杂类草地上生物量减少显著,枯草生物量增加显著,禾草和优良牧草的生物量以及总地上生物量增加不显著,优良牧草比例由0.57下降为0.48.退化矮嵩草草甸在封育条件下,枯草、禾草生物量增加显著,莎草、优良牧草的生物量及总生物量增加不显著,优良牧草比例则由0.29上升为0.48,达到显著水平.未退化矮嵩草草甸的草地质量指数明显下降,退化矮嵩草草甸的草地质量指数则明显上升.

... 土壤种子库在植被经历干扰后是其恢复的主要种源,在退化草地的恢复与重建中承担着重要的角色,而且能够反映种群对环境变化的响应^[3] ...

2010

0.0

. 2010, 19(2):227-234 DOI:doi:10.3724/SP.J.1077.2010.01263

Review of research on seed banks of desert regions

干旱荒漠区土壤种子库研究进展

Yang L , Wang Y R , Yu J D

杨磊, 王彦荣, 余进德

荒漠生态系统是地球上最脆弱的生态系统。近年来,荒漠生态系统保护和恢复的研究已受到广泛关注。土壤种子库作为种子源,在植被恢复过程中起着至关重要的作用。本研究系统回顾了近20年来国内外对干旱荒漠区土壤种子库的研究进展,从土壤种子库的基本特征、时空分布、与地上植被的关系、研究方法以及影响因素等方面进行综述并提出研究展望。

... 植被演替的过程不仅包括地上植被组成与结构的变化,同时也包括土壤种子库的数量与格局的变化^[4] ...

2010

0.0

. 2010, 30(1):104-109

Microorganisms, soil nutrient and enzyme activity changing with the proceeding of desert steppe degradation in Inner Mongolia

荒漠草原不同退化阶段土壤微生物、土壤养分及酶活性的研究

L#cod#x000fc; G F , Wu Y S , Li H

吕桂芬, 吴永胜, 李浩

... 随着全球气候变化、人为开发过度等因素,作为我国草原生态系统的重要组成部分的荒漠草原,目前也承受着巨大的压力^[5,6] ...

2005

0.0

... 随着全球气候变化、人为开发过度等因素,作为我国草原生态系统的重要组成部分的荒漠草原,目前也承受着巨大的压力^[5,6] ...

2017

0.0

. 2017, 25(1):76-81 DOI:doi:10.11733/j.issn.1007-0435.2017.01.012

Effects of enclosure on soil aggregate distribution and stability of desert steppe in Ningxia

围封对宁夏荒漠草原土壤团聚体组成及其稳定性的影响

Wang G H , Wang J J , Tao L B

王国会, 王建军, 陶利波

以空间序列代替时间序列,采用干筛法和湿筛法研究了围封禁牧条件下宁夏荒漠草原恢复演替过程中0～40cm土层土壤团聚体组成、破坏率及平均重量直径(MWD)等指标,以探讨围封对荒漠草原土壤团聚体稳定性的影响.结果表明:围封有利于荒漠草原土壤团聚体的形成,随围封年限的增加,＜0.25 mm土壤微团聚体含量总体呈下降趋势.其中,＜0.25 mm干筛团聚体含量在0～10 cm和10～20 cm土层变化显著,均以围封10年的草地最低;＜0.25 mm水稳性团聚体含量在0～10 cm和20～40 cm土层变化显著,其中0～10 cm土层以围封7年的草地最低,20～40 cm土层以围封10年的草地最低;随围封年限的增加,土壤团聚体平均重量直径呈先降低后增加的趋势,以围封10年的草地最高,团聚破坏率则以围封7年、10年的草地较低,未封育和封育3年的草地较高.从垂直分布看,随剖面深度的增加,大团聚体特别是＞5 mm粒级团聚体含量显著增加.

... 由于荒漠草原是宁夏草原的主体类型,因此宁夏退牧还草的效果也主要取决于荒漠草原的恢复程度^[7] ...

2016

0.0

. 2016, 36(3):579-587 DOI:doi:10.7606/j.issn.1000-4025.2016.03.0579

Comparative studies on soil enzymic activities of four kinds of common plant communities in desert steppe

荒漠草原4种常见植物群落土壤酶活性比较

Shao W S , Li G Q , Chen K Y

邵文山, 李国旗, 陈科元

In this paper, Sophora alopecuroides , Achnatherum splendens , Artermisia ordosica and Kalidium foliatum are 4 kinds of common plant communities growing in Yanchi County of Ningxia Province.They were taken as examples to study the soil microenvironment of different plant communities in desert steppe.After the study of community composition,the basic physical and chemical properties of the soil,we measured urease,catalase,phosphatase,sucrase.The results showed that:(1)the species composition of the different plant communities were various,and the frequency of occurrences of Gramineae,Compositae,Chenopodiaceae were relatively high in survey region.(2) There were differences on soil physical and chemical properties in the 4 kinds of plant communities.For example,the soil bulk density was less in S.alopecuroides community and the total nitrogen was relatively higher,the pH and organic carbon content of soil were significantly higher than others in A.splendens community.The soil moisture content and total phosphorus were lower in A.ordosica community and the salt content was higher markedly in K.foliatum community.(3) There were differences of soil enzyme activity among 4 kinds of plant communities.The urease activity of A.splendens and A.ordosica communities topsoil soil（0-10 cm）was higher;soil catalase of A.ordosica and K.foliatum communities increased as soil deepening;soil phosphatase activity of S.alopecuroides and A.splendens communities were higher and soil phosphatase activity of K.foliatum community was no significant difference in various soil layer（ P >0.01）;soil sucrase activity of 4 kinds of communities was generally low,and the little difference between the soil layer.(4) The correlation of the same soil enzyme activity was different among various plant communities.In conclusion,the different plant community characteristics and soil traits,especially the correlations of soil enzyme activities among different plant communities,can predict the succession of plant communities in desert steppe,and can be used as ways of vegetation restoration of desert steppe on the other hand.That is,moderate artificial disturb can raise soil enzyme activity,then increase biomass,which make desert steppe onto positive succession.

该研究以宁夏盐池县沙边子地区4种常见的植物群落苦豆子（ Sophora alopecuroides ）、芨芨草（ Achnatherum splendens ）、油蒿（ Artermisia ordosica ）和盐爪爪（ Kalidium foliatum ）为研究对象，通过对群落组成和土壤基本理化性质的研究，以及对脲酶、过氧化氢酶、磷酸酶、蔗糖酶4种常见土壤酶活性的检测，分析了荒漠草原不同植物群落的土壤微环境。结果表明：（1）不同植物群落物种组成不同，且在研究区禾本科、菊科、藜科植物出现的频率相对较高。（2）不同植物群落土壤理化性质存在差异。苦豆子群落土壤容重较低，土壤全氮含量相对较高；芨芨草群落土壤pH明显较高，土壤有机碳含量相对较高；油蒿群落土壤水分含量较低，土壤全磷含量较低；盐爪爪群落土壤盐分含量显著高于其它植物群落。（3）不同植物群落土壤酶活性存在差异，其中芨芨草和油蒿群落的表层土（0~10 cm）的土壤脲酶活性较高；油蒿和盐爪爪群落的土壤过氧化氢酶随着土层加深酶活性反而有升高趋势；苦豆子和芨芨草群落的土壤磷酸酶活性较高，盐爪爪群落各土层间磷酸酶活性无显著差异；4种群落土壤蔗糖酶活性普遍较低，且各土层间差异也不大。（4）不同植物群落的同种土壤酶活性间相关性不同。研究认为，根据不同植物群落特征及土壤特性，尤其是不同植物群落间土壤酶活性的相关性，可预测荒漠草原地区植物群落演替趋势，通过适度的人为调控，可使群落向进展方向演替。

... 苦豆子和芨芨草群落的土壤磷酸酶活性较高,而蔗糖酶活性普遍较低^[8] ...

... 地形主要为缓坡丘陵,土壤类型主要为灰钙土、风沙土等,土壤质地以风沙土为主^[8] ...

2003

0.0

. 2003, 12(4):90-99 DOI:doi:10.3321/j.issn:1004-5759.2003.04.017

Effects of enclosure management on the structure of soil seed bank and standing vegetation in degraded sandy grasslands of eastern Inner Mongolia

封育对退化沙质草地土壤种子库与地上群落结构的影响

Li F R , Zhao L Y , Wang S F

李锋瑞, 赵丽娅, 王树芳

对封育和未封育放牧草地土壤种子库、地上幼苗库和定植群落的结构特征进行了比较研究,并探讨了地上植被与土壤种子库密度的关系,主要结论是:1)对退化沙地实施封育措施后显著提高了地上植被与土壤种子库的密度和植物种数,特别是显著增加了地上与土壤种子库群落中优良禾草的种数与密度,草地质量得到很大改善.2)地上植被与土壤种子库对放牧干扰的响应模式不同,放牧对地上植被种丰富度的影响要明显大于土壤种子库,而对土壤种子库密度的影响又明显大于地上植被.3)由于放牧显著降低了地上植被与土壤种子库的共有种数,从而降低了地上植被与土壤种子库组成上的相似性.另外,封育和未封育草地在种子库组成上的相似性要高于地上植被组成上的相似性,提供了放牧更强烈地影响地上植被组成的重要佐证.4)回归分析显示,土壤种子库密度与地上早期幼苗库密度和后期定植群落密度以及幼苗库密度与定植群落密度之间均存在显著的正相关性,早期幼苗库密度的56%的变异可归结为土壤种子库密度的变异,而后期定植群落密度的77%的变异可由早期幼苗库密度的变异来解释.

... 本试验中种子库的鉴定主要采取种子过筛直接辨认和种子萌发试验鉴定^[9] ...

2015

0.0

. 2015, 35(7):2285-2294 DOI:doi:10.5846/stxb201306041326

Varying characteristics of soil seed banks during the succession process of Nitraria tangutorum vegetation in an arid desert area

干旱荒漠白刺灌丛植被演替过程土壤种子库变化特征

Ma Q L , Lu Q , Wei L Y

马全林, 卢琦, 魏林源

The seed bank is the collection of viable seeds present on or within the soil at any given time. Soil seed bank is an important indicator in response to changes in land utilization and climate, and also forms the basis for desert vegetation restoration and development. Nitraria vegetation is typical of desert vegetation and with nebkhas is widely distributed along the periphery of oasis in the arid regions of Northwest China, playing an important role in desertification control around oases. In recent decades, Nitraria vegetation in the oasis-desert ecotone has been seriously degraded due to the rapid decrease of the groundwater table caused by agricultural over development. However, there is little information regarding the change in characteristics of the soil seed bank of Nitraria nebkhas in arid desert areas. Using the method of substituting space for time, the species composition, distribution pattern and quantitative variation of soil seed banks of N. Tangutorum nebkhas in initial, stable, degraded and severely degraded stages were studied in the lower reaches of the Shiyang River. Results showed that the soil seed bank of N. Tangutorum nebkha in the lower reaches of the Shiyang River was composed of 18 species, belonging to 9 families. Herb species accounted for 55%-80% and were the main body of soil seed banks. The soil seed density of the stable stage was 660.7 seeds/m 2 , and was the highest, being 5.6, 14.5 and 6.2 times greater than those measured in the initial stage, degraded stage and severely degraded stage, respectively. The soil seed density of the degraded stage was 45.7 seeds/m 2 , and was the lowest, only accounting for 38.9%, 6.9% and 42.5% of those measured in the initial stage, stable stage and severely degraded stage, respectively. The soil seed density of the N. Tangutorum population at the different succession stages was also significantly different, showing a decreasing trend after the initial increase. The soil seed density of N. Tangutorum population at the stable stage reached 9.33 seeds/m 2 . The soil seed density in different positions of N. Tangutorum nebkhas was significantly different and was mainly distributed in the central parts of the windward and leeward slopes of N. Tangutorum nebkhas, with seed densities of 329 seeds/m 2 and 309 seeds/m 2 , respectively. The mean soil seed density of the nebkhas was 1.9 times that in the depressions within the nebkhas. Similarity coefficients of soil seed banks between the different succession stages were less than 0.6, which were recognized as having a moderate similarity level except for the stable stage which showed a low similarity coefficient. There were more common species which accounted for over 65% of vegetation above ground and the soil seed bank. Similarity coefficients between vegetation above ground and the soil seed bank were more than 0.5, which showed a moderate to extreme similarity level, and demonstrated a decreasing trend after the initial increase. The findings have proven the importance of soil seed banks and Nitraria nebkhas in Nitraria vegetation and also suggest that human disturbance has impacted potential underground vegetation and its restoration capacity. Therefore, man-made soil seed banks or vegetation construction should be adopted to contain Nitraria nebkhas activation and restore degraded Nitraria vegetation in arid desert areas.

土壤种子库是反映气候与土地利用变化的指示器,也是荒漠植被更新与恢复的基础。典型荒漠白刺灌丛植被广泛分布于我国西北绿洲边缘地带,对保护绿洲免受风沙危害发挥着重要作用。但是,对干旱荒漠白刺灌丛植被土壤种子库仍未见研究报道。应用空间代替时间的方法,选择石羊河下游白刺灌丛植被演替的初始阶段、稳定阶段、衰退阶段与严重衰退阶段样地,研究了白刺灌丛植被演替过程的土壤种子库物种组成、时空分布和数量变化特征。结果表明:石羊河下游白刺灌丛植被演替过程中,土壤种子库共出现9科18种植物,其中草本植物占到55%-80%,是白刺灌丛植被土壤种子库的主体。不同演替阶段土壤种子库密度以稳定阶段最高,达到660.7 粒/m 2 ,是初始阶段、衰退阶段和严重衰退阶段的5.6、14.5倍和6.2倍。不同沙堆部位,土壤种子库密度以迎风坡中部与背风坡中部最高,分别达到329 粒/m 2 和309 粒/m 2 ;沙堆土壤种子库密度是堆间地的1.9倍,土壤种子库主要分布于灌丛沙堆上。不同演替阶段土壤种子库间的相似性系数均在0.6以下,除稳定阶段外,其他阶段间均属于中等相似水平;土壤种子库与地上植被的相似性系数均在0.5以上,达到中等相似或极相似水平。该研究进一步证明了灌丛沙堆和土壤种子库在白刺灌丛植被中的重要性,也说明人为干扰损害了白刺灌丛地下潜在植被及其恢复潜力。因此,需要开展人工种子库或人工植被建设以控制干旱荒漠白刺灌丛沙堆活化,并实现退化白刺灌丛植被恢复。

... 3 计算方法将鉴定的土壤种子数量换算成1 m²种子数量^[10],根据土壤种子库物种和种子密度计算Shannon-Wiener多样性指数、Simpson 多样性指数、Pielou均匀度指数、Margalef丰富度指数^[11,12] ...

2013

0.0

. 2013, 24(3):801-808

Soil seed bank and its correlations with aboveground vegetation and environmental factors in water level fluctuating zone of Danjiangkou Reservoir, Central China

丹江口水库消落带土壤种子库与地上植被和环境的关系

Liu R X , Zhan J , Shi Z H

刘瑞雪, 詹娟, 史志华

Taking the water level fluctuating zone of the Danjiangkou Reservoir as a case, and by the method of hierarchical cluster analysis, the soil seed banks at 37 sampling plots within the areas of 140-145 m elevation were divided into 6 groups, and the species composition, density, and diversity of the soil seed banks among the groups were compared. The differences between the soil seed banks and the aboveground vegetations were analyzed by S-rensen similarity coefficient, and the correlations among the soil seed banks, aboveground vegetations, and environmental factors were explored by principal component analysis (PCA) and multivariable regression analysis. At the same altitudes of the water level fluctuating zone, the species composition of the soil seed banks had obvious heterogeneity, and the density and diversity indices of the soil seed banks among different groups were great. The similarity coefficient between the soil seed banks and aboveground vegetations was low, and the species number in the soil seed banks was obviously lesser than that in the aboveground vegetations. The density of the soil seed banks was highly positively correlated with the aboveground vegetations coverage and species number and the soil texture, but highly negatively correlated with the soil water-holding capacity and soil porosity.

以丹江口水库消落带为研究区域,利用层次聚类法将海拔140～145 m区域内37个样地的土壤种子库分为6个组,比较不同组间的种子库物种组成、密度及多样性指数之间的差异;利用相似性指数分析土壤种子库与地上植被的差异;运用主成分分析和多元回归分析土壤种子库密度与地上植被、环境因素的关系.结果表明: 在丹江口水库消落带同海拔区域内,土壤种子库在物种组成上呈明显的异质性,不同组间的种子库密度、多样性指数均存在显著差异;土壤种子库与地上植被的差异较大,而且土壤种子库中的物种数明显少于地上植被中的物种数;土壤种子库密度与地上植被盖度、地上物种数和土壤质地呈显著正相关,而与田间持水量和土壤孔隙度呈显著负相关.

2004

0.0

2011

0.0

. 2011, 31(3):703-709

Effects of grazing systems on germinable soil seed bank of desert steppe

放牧制度对荒漠草原可萌发土壤种子库的影响

Yan R R , Wei Z J , Xin X P

闫瑞瑞, 卫智军, 辛晓平

... 采用Sorensen相似性系数计算土壤种子库封育内外群落组成的相似性^[13] ...

2006

0.0

. 2006, 12(3):313-317 DOI:doi:10.3321/j.issn:1006-687X.2006.03.004

Soil seed banks of degraded alpine grassland in headwater region of the Yellow River: quantities and dynamics of seed germination

黄河源区退化高寒草地土壤种子库: 种子萌发的数量和动态

Shang Z H , Long R J , Ma Y S

尚占环, 龙瑞军, 马玉寿

对青藏高原黄河源区不同退化程度高寒草地的土壤种子库土样用土壤分析筛进行浓缩,并以萌发法分析土壤种子库萌发种子数量和动态.结果表明,孔径0.25～2 mm的土壤分析筛分离土样中萌发种子可达萌发种子总量的85%～97%,而小于0.25 mm的土样中未发现种子.因此,用0.25 mm孔径大小的土壤筛对高寒草地土壤种子库土样进行大规模浓缩是一种方便、可靠的方法.4种不同退化程度高寒草地(A:未退化草甸;B:轻度退化草甸;C:中度退化草甸;D:重度退化草甸)的土壤种子库在实验室条件下萌发的种子数量分别为:A 1 194～3 744粒/m2,平均2 421.3粒/m2;B 5 376～1 0912粒/m2,平均7 786.7粒/m2;C 2 304～1 3216粒/m2,平均8 695.5粒/m2;D 4 768～12 352粒/m2,平均8 125.9粒/m2.除样地A外,其它3个样地的可萌发种子数量差异不大.单子叶植物种子在培养到d 10左右开始萌发,双子叶植物在5～7 d内开始萌发,前者3 wk后基本不再萌发,后者5 wk左右停止萌发.4个样地土壤种子库种子萌发主要集中在第2～3周,并表现出近似单峰型格局.图1表3参39

... 1 封育内外土壤种子库的物种组成不同草地类型的土壤种子库差异较大,用不同的研究方法也会导致研究结果的不同^[1,14] ...

1982

0.0

... Silvertown^[15]研究表明草地土壤种子库的范围在10³~10⁶粒#cod#x000b7 ...

... m^-2,本试验中土壤种子库的规模符合Silvertown^[15]的研究结果 ...

2009

0.0

. 2009, 29(7):3658-3664 DOI:doi:10.3321/j.issn:1000-0933.2009.07.025

A comparison of the soil seed bank in an enclosed vs. a degraded alpine meadow in the eastern Tibetan Plateau

青藏高原东缘封育和退化高寒草甸种子库差异

Ma M J , Zhou X H , L#cod#x000fc; Z W

马妙君, 周显辉, 吕正文

We used the direct germination method to examine the difference in the soil seed bank between an enclosed and a degraded alpine meadow in the eastern Tibetan Plateau. The main results and conclusions were: (1) A total of 10161 seedlings germinated in the two sites, belonging to 46 species and 23 families. The proportion of perennials was higher in the enclosed site than in the degraded site, but the proportion of grasses and monocotyledons was not different between the two sites. (2) The mean seed density in the degraded site ((6105±1530) viable seeds m-2) was significantly higher than in the enclosed site ((3883±798) m-2), but there was no difference in species richness between the two sites. The larger seed bank in the degraded area indicates that restoration of this habitat is not seed limited, and the soil seed bank has the potential to be a source for restoration. (3) Species richness and seed density decreased significantly with depth. (4) We used S rensen′s coefficient to evaluate the relationship between the presence of species in the germinable seed bank and the aboveground vegetation. This relationship was weak, though stronger for the enclosed site (45.3%) than for the degraded site (40.4%). However, the similarity of seed bank between the two sites was high (84.6%), indicating that while grazing pressure has a dramatic effect on vegetation, the impact of these changes is buffered by the soil seed bank. (5) The Shannon-Wiener index in the enclosed site was significantly greater than in the degraded site, both for the seed bank and for the aboveground vegetation. Thus, overgrazing reduces both the species diversity of aboveground vegetation and the diversity of the seed bank. Management by enclosing pastures could maintain the species diversity of both the seed bank and the aboveground vegetation.

采用幼苗萌发法研究了青藏高原东部高寒草甸封育和退化地区土壤种子库的差异。结果表明：(1）两个样地总共有10161株幼苗萌发，分属55个物种，23个科。封育样地多年生植物比例高于退化样地，禾草和单子叶植物比例在两个样地间差异不大。(2）退化样地土壤种子库种子密度（(6105±1530) m-2）显著高于封育样地（(3883±798) m-2），而物种丰富度差异不显著。所研究区域拥有较为丰富的种子库资源，退化地区资源更丰富，说明恢复不存在种子限制问题，土壤种子库可以成为植被恢复的潜在资源。(3）种子密度和物种丰富度在垂直分层上差异显著，且随着深度的增加而显著减小。(4）用Srensen coefficient指数计算出土壤种子库和地上植被之间的相似性在整体上较低，封育样地（45.3%）略高于退化样地（40.4%），两个样地地上植被之间的相似性为50％，而种子库之间相似性高达84.6%，说明种子库起到一个“缓冲器”的作用。(5）Shannon-Wiener多样性指数分析显示，无论在地上植被或种子库中，物种多样性都是封育样地显著高于退化样地。过度放牧不仅导致地上植被的生物多样性丧失，而且使种子库中的物种多样性降低，而封育管理可以维持地上植被和种子库中的物种多样性。

... 还有研究结果认为退化样地土壤种子库种子密度显著高于封育样地^[16] ...

... 3 土壤种子库多样性分析本研究表明,围栏封育可增加不同植物群落土壤种子库的多样性、均匀度和丰富度,这与有关封育对土壤种子库影响的研究结果相一致^[16,23,24],有学者对典型草原封育过程中土壤种子库的变化进行了研究,结果表明土壤种子库多样性和物种丰富度变化与封育年限有关^[25] ...

2009

0.0

. 2009, 18(2):731-737 DOI:doi:10.3969/j.issn.1674-5906.2009.02.060

A review of study on soil seed bank in the past thirty years

近30年来土壤种子库研究的回顾与展望

Li H Y , Mo X Q , Hao C

李洪远, 莫训强, 郝翠

土壤种子库(Soil Seed Bank)是指单位面积的土壤及土壤表面的落叶层中所有具有生命力的种子的总和.由于土壤种子库在植被的更新和恢复、生物多样性的维护、植被的演替过程和扩散过程等方面都具有重要作用,近年来成为生态学和土壤学等学科的研究热点.文章查阅了近30年来发表的关于土壤种子库研究的代表性SCI论文,首次运用文献分析与管理软件Endnote X1和Refviz对该研究领域的相关文献进行了系统的分析,结果发现:有关土壤种子库论文发表数量逐年增长的同时,每个年代末会呈现一个明显的峰值.在此基础上,根据不同年代研究的内容和特点,初步将土壤种子库的研究划分为三个主要阶段:(1)土壤种子库研究的探索阶段(1978-1989年);(2)土壤种子库研究方法与内容的成熟阶段(1990-1999年);(3)土壤种子库理论体系与研究内容扩展阶段(2000年至现在),并对各个阶段的研究重点和主要研究成果进行了详细的综述.最后就长久土壤种子库调查、种子库年际变化、干扰影响机制等研究热点做了展望,为今后土壤种子库的研究工作提供了参考策略.

... 2 土壤种子库垂直分布格局土壤种子库具有明显的垂直分布格局,这种立体结构影响着种子库种子的萌发和留存,进而影响着未来植被的恢复与重建^[17] ...

... 05),这与大多数的研究结果一致^{[17,20,21,22]} ...

1998

0.0

... Bekker等^[18]提出在没有遭到破坏的土壤生境中,0~5 cm土壤层中的种子垂直分布符合一定的数学模型,有研究表明^[19]土壤种子在土壤层中呈二项式分布或泊松分布 ...

1997

0.0

2003

0.0

. 2003, 14(9):1457-1463

Soil seed banks of different grassland types of Alashan arid desert region, Inner Mongolia

阿拉善干旱荒漠区不同植被类型土壤种子库研究

Zeng Y J , Wang Y R , Nan Z B

曾彦军, 王彦荣, 南志标

Investigations on the soil seed banks of different grassland types of Alashan arid desert region in Inner Mongolia showed that when the altitudes of sampling plots increased from 1370 m to 1750 m, the soil seed densities of natural grasslands decreased from 326 grain·m -2 to 76 grain·m -2 .At the altitude of 1100 m, the soil seed density was 56 grain·m -2 in typical desert plot, but only 8 grain·m -2 in the sand dune plot.After the vegetation was restored with Artemisa sphaerocephala on sand dune, its soil seed density increased obviously, almost as 17～29 times as sand dune's.In this study, 31 seeds m -2 were sampled, which belonged to 11 families.Among them, annual plants accounted for 77%, 100% and 70%, perennial plants accounted for 21%, 0 and 16%, and semi-shrubs accounted for 2%, 0 and 14%, respectively for natural grassland, sand dune and sown grassland.Shrub seeds were not found in all the soil seed bank plots.When the altitudes of sampling plots increased from 1100 m to 1750 m, the species richness (Margalet index) of soil seed banks of natural grasslands increased from 1.49 to 2.77, and the species diversity (Shannon-Winner index) increased from 0.697 to 0.917.

对阿拉善干旱荒漠区不同草地类型土壤种子库的研究表明,在海拔高度为1370～1750m样地间,天然草地土壤种子密度从326粒·m -2 减少至76粒·m -2 ,呈随海拔高度增加而减少的趋势。海拔高度为1100m的典型荒漠区,土壤种子密度为56粒·m -2 沙漠区土壤种子密度仅为8粒·m -2 ,在沙漠区建立白沙蒿草地后,其土壤种子密度明显增加,为沙漠区的17～29倍。本研究共统计到31种植物种子,分属11科。其中,以一年生草本植物种子的比例最高,分别在天然草地、沙漠区和飞播白沙蒿样地种子库中占77%、100%和70%;多年生草本植物次之,分别占21%、0和16%;半灌木种子比例最低,分别占2%、0和14%,所有种子库中未发现灌木的种子,在海拔高度为1100～1750m样地间,天然草地土壤种子库的丰富度指数从1.49增至2.77,多样性指数从0.697增至0.917,呈随海拔高度的升高而增加趋势。

... 05),这与大多数的研究结果一致^{[17,20,21,22]} ...

2014

0.0

... 05),这与大多数的研究结果一致^{[17,20,21,22]} ...

2013

0.0

... 05),这与大多数的研究结果一致^{[17,20,21,22]} ...

2008

0.0

. 2008, 25(10):78-83

Characteristics of soil seed banks in grassland under fencing and grazing in Loess Plateau

黄土高原草地封育与放牧条件下土壤种子库特征

Zhao L P , Cheng J M , Wan H E

赵凌平, 程积民, 万惠娥

Characteristics of soil seed bank, such as species composition, density and diversity in semiarid grassland on loess plateau under fencing and grazing conditions were investigated. The main inclusions were: 1) fencing greatly increased plant species and density of soil seed banks, palatable grass and perennial plant increased; 2) with the increasing soil depth, seeds decreased quickly; 3)Slope direction and position had a tremendous effect on soil seed banks. Density followed the order of southern slope > northern slope; slope bottom >medium > top; 4) The results of the study indicated that the Margalef and the ShannonWiener diversity indexes of soil seed banks in fenced area were higher than enclosed grassland, while Pielou evenness indexes were higher in the latter.

对半干旱区黄土高原草地在封育和放牧条件下土壤种子库种子密度、种子库组成、种子库物种多样性及均匀性进行了比较研究,并得出主要结论：1）封育提高土壤种子库的植物种类和密度，使优良禾草和多年生植物增加。2）种子库的垂直分布规律是随着土层的加深，种子在数量上递减的速度较快。3）坡向和坡位对土壤种子库有较大影响，种子库密度变化趋势是阴坡>阳坡；坡下部>坡中部>坡上部。4）从丰富度、ShannonWiener多样性和均匀性3个方面比较分析封育和放牧样地土壤种子库多样性,得出封育样地Margalef丰富度指数和ShannonWiener指数都高于放牧地，Pielou均匀性指数低于放牧地。

2011

0.0

. 2011, 19(1):38-42

Soil seed bank dynamics during natural restoration by fence in a typical steppe of Inner Mongolia

典型草原封育过程中土壤种子库的变化特征

Huang X Y , Wang K , Wang Y T

黄欣颖, 王堃, 王宇通

2015

0.0

. 2015, 35(14):4725-4732

Response of a soil seed bank to modes of grassland management on a desert steppe

荒漠草原土壤种子库对草地管理方式的响应

Shen Y , Liu C F , Ma H B

沈艳, 刘彩凤, 马红彬

2009

0.0

. 2009, 33(2):320-330 DOI:doi:10.3773/j.issn.1005-264x.2009.02.009

Pattern analysis of inter specific relationships in four arid communities in sand lake Ningxia Hui Autonomous region, China

宁夏沙湖4种干旱区群落中主要植物种间关系的格局分析

Liu X K , Liu M S , Huang Z

刘小恺, 刘茂松, 黄峥

Aims Inter-specific interactions in plant communities can be characterized by their spatial relationships. Because these interactions are usually asymmetrical, i.e., one species exerts more influences on the other, asymmetric spatial patterns should be expected. Our objective was to study how species spatially adapt to arid conditions in four typical arid communities that differed in growth-form composition (tree-grass, shrub-grass, shrub-semishrub and forb-grass). Methods We selected four representative arid plant communities near Sand Lake in Xidatan, Pingluo County, Ningxia Hui Autonomous Region and measured the position, height and crown diameter of each individual in a 30 m × 30 m plot in each community. We applied the bivariate Ripley’s K function in spatial association analysis and developed a new method named pattern control analysis (PCA) for investigating asymmetric spatial relationships. PCA was derived from the assumption that the controlled species should be distributed around the controlling species regularly at a specific scale. Two simulated community patterns were used to test the new method. Important findings In communities of Elaeagnus angustifolia - Achnatherum splendens (EA), Nitraria tangutorum - A. splendens (NA) and A. splendens - Sophora alopecuroides (AS), significant positive spatial associations were detected between the dominant species (at scales of 0–15 m, 0–7.5 m and 0–7 m, respectively), and species pairs with positive spatial association significantly differed with each other in growth form. In the community of Reaumuria soongorica - Kalidium foliatum (RK), negative spatial association was detected (at the scale of

格局分析是研究群落结构、种群特征、种内种间关系以及生物与环境间相互作用的重要手段。应用Ripley’s K函数的双变量点格局分析技术, 对宁夏沙湖4种干旱区群落中主要植物种间的空间关联关系进行了研究; 同时, 根据关联物种间相对位置的规则性, 基于Ripley’s K函数, 提出一种用于检测种间格局控制关系的技术方法。研究结果表明:1) 沙枣( Elaeagnus angustifolia )-芨芨草( Achnatherum splendens )、芨芨草-苦豆子( Sophora alopecuroides )、白刺( Nitraria tangutorum )-芨芨草3个群落中, 主要物种间在个体大小、根系特点和生态习性等方面存在较大的差异, 并分别在一定的尺度范围内存在正关联关系; 而在物种生态需求和形态大小等方面相对一致的红砂( Reaumuria soongorica )-盐爪爪( Kalidium foliatum )群落中, 红砂和盐爪爪之间在整个观测尺度内(0~15 m)存在负关联关系。2) 格局控制分析表明, 在主要物种间存在空间正关联关系的3个群落中, 均检测出主要物种间在一定尺度范围内存在格局控制关系, 其中格局控制种一般个体较大、生境改造能力较强; 而在主要物种生活型相似的红砂-盐爪爪群落中, 未检测到主要物种间的格局控制关系。

... 本研究中,2种植物群落封育内外土壤种子库间的相似性相对较高,一方面荒漠草原植物种本身相对较少,大多是适应度较高的植物种,有关苦豆子和芨芨草作为伴生群落的研究也有报道^[26,27] ...

2009

0.0

. 2009, 33(4):748-754 DOI:10.3773/j.issn.1005-264x.2009.04.013

. Distribution pattern of root biomass and inter specific relationship in Achnatherum splenoens-Sophora alopecuroides community in Northwest China

我国西北地区芨芨草#cod#x02014;#cod#x02014;苦豆子群落根系分布与种间关系

Chen L M G , Liu M S , Huang Z

晨乐木格, 刘茂松, 黄峥

1School of Life Science, Nanjing University, Nanjing 210093, China;2College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China

Aims Linking spatial patterns to ecological processes is a central topic in ecology. Inter-specific relationships in arid plant communities have been extensively studied by investigating aboveground patterns, but research on underground distribution patterns is inadequate. Our objective was to explore the inter-specific relationships between two dominant species, Achnatherum splendens (grass) and Sophora alopecuroides (forb), in a typical grass-forb community of arid/semi-arid regions of China. Methods We selected a 30 m × 30 m plot in a representative A. splendens - S. alopecuroides community in Sand Lake, Ningxia Hui Autonomous Region, Northwest China. The two dominant species usually spatially assemble as clumps aboveground. We partitioned the spatial gradient from the base of the assemblages to the non-vegetated open spaces between assemblages into under-canopy, transitional and open subareas to characterize the horizontal differences of microhabitat. Five assemblages of the two species were randomly chosen, and a 150 cm deep soil profile with coverage of 100 cm ×100 cm was excavated in each subarea. Root biomass in terms of fine roots (diameter Important findings Horizontally, biomass density of the total roots of A. splendens decreased along the gradient from under-canopy to open subareas. Also, ANOVA showed that biomass density of the total roots significantly differed among the three subareas for A. splendens , but no significant differences were detected for S. alopecuroides . Vertically, the soil layers with the highest biomass density of the total and fine roots of A. splendens increased in depth from under-canopy to open subareas, while that of the total roots of S. alopecuroides remained at 10–30 cm depth and that of the fine roots of S. alopecuroides tended to decrease in depth along the gradient. Also, the fine roots of the two species were different in the highest biomass density layer in the under-canopy subareas where root systems were densely distributed, but showed similar vertical patterns in the transition and open subareas. Niche separation in the under-canopy subareas and discrepancy in horizontal patterns of the two dominant species could represent an important adaptive strategy of avoiding direct competition and facilitating coexistence in arid communities.

以宁夏沙湖的一个典型的干旱区草本型植物群落——芨芨草( Achnatherum splendens )-苦豆子( Sophora alopecuroides )(禾草-非禾草型)群落为研究对象, 自芨芨草-苦豆子聚生丛的基部向丛间裸地依次划分为植冠区、过渡区和空旷区3个分区, 通过比较分析两个优势种根系生物量密度在这3个分区的空间分布格局, 研究了干旱胁迫生境中芨芨草和苦豆子的根际关系。结果表明: 在水平方向上, 芨芨草根系总生物量主要集中分布于植冠区, 而苦豆子根系总生物量密度在3个分区间无显著差异; 在垂直方向上, 芨芨草的根系总生物量密度和细根生物量密度最大的土壤层次从植冠区到空旷区埋深渐深, 而苦豆子的根系总生物量在3个分区主要分布于10～30 cm土层, 但其细根生物量密度最大的土层从植冠区向外呈上升趋势; 同时发现, 在植冠区, 根系总生物量密度较高, 两种植物细根生物量密度最大的土壤层次不同, 但在空旷区和过渡区, 两种植物细根生物量密度的垂直分布格局趋于一致。群落中两个主要植物种的根系在植冠区具有垂直层次的分异性, 在不同分区间具有水平分布格局的差异性, 这可能是群落中两种主要植物种间为了避免根系间直接竞争共同适应干旱胁迫生境的重要机制。