,1,*, 马望1,2, 何鹏3, 梁潇洒1, 王正文1Extreme drought effects on nonstructural carbohydrates of dominant plant species in a meadow grassland
Lin SONG1,2, Wen-Tao LUO,1,*, Wang MA1,2, Peng HE3, Xiao-Sa LIANG1, Zheng-Wen WANG1通讯作者: *wentaoluo@iae.ac.cn
编委: 彭长连
责任编辑: 李敏
| 基金资助: |
Corresponding authors: *wentaoluo@iae.ac.cn
Online:2020-06-20
| Fund supported: |
摘要
植物光合作用产生的非结构性碳水化合物(NSCs)水平可以反映植物和生态系统对环境变化的响应程度。近年来, 草原极端干旱事件的发生频率和持续时间增加趋势明显, 对生态系统结构和功能产生深远影响。该研究以内蒙古呼伦贝尔草甸草原为研究对象, 通过连续4年减少66%生长季降水量的控制实验来模拟极端干旱事件, 分析草原6种优势物种和植物功能群NSCs各组分对极端干旱的响应规律与机制。结果显示, 由于植物生物学、光合特性以及生理生态等特性的差异, 不同物种对干旱胁迫的响应具有明显差异。这表明草地植物NSCs组分及其利用策略对干旱胁迫的响应具有物种特异性, 从而导致其生物量的不同响应。将6种植物分为禾草和非禾草两类, 发现干旱显著增加了禾草的淀粉含量, 但对其可溶性糖含量无显著影响; 相反, 干旱显著增加了非禾草功能群的可溶性糖含量, 对其淀粉含量无显著影响, 表明不同功能群采取了不同的干旱应对策略。禾草选择将光合作用固定的能量进行储存以应对干旱胁迫, 其生物量对干旱响应不敏感; 而非禾草选择将能量以可溶性糖的形式直接供植物生长利用以及抵御干旱胁迫, 其生物量对干旱响应较为敏感。这一发现可为预测在全球气候变化背景下草甸草原生态系统结构与功能对极端干旱的响应提供科学参考。
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Abstract
Aims Plant nonstructural carbohydrates (NSCs) produced by photosynthesis can reflect the responses of plants and/or ecosystem to environmental changes. Climate models recently predicted an increase in the frequency and duration of extreme drought (ED) events that could profoundly impact ecosystem structure and functions. Yet, less is understood about the response patterns of different plant species and functional groups to extreme drought.
Methods Here we studied the effects of extreme drought on the NSCs of dominant species belonging to different functional groups in grasslands. To achieve ED, we experimentally reduced precipitation amounts by 66% during four consecutive growing seasons in a meadow steppe in Hulunbeier, North China. The NSCs of six plants grouped into two functional groups (i.e., grass and non-grass) were examined.
Important findings We found different species responded differently to drought, due to their differences in plant biological characteristics, photosynthetic characteristics and physiological ecology. This result implied that different species used different NSC-use strategies to cope with drought stress, resulting in different responses of their biomass to extreme drought. Extreme drought significantly increased the starch concentrations, and had no effect on the soluble sugar concentrations of the grass functional group. Contrarily, ED significantly increased the soluble sugar concentrations, and had no significant effects on the starch concentrations of the non-grass functional group. These results indicate that grasses moderately use and store photosynthate to cope with drought stress, hence their biomass was less sensitive. The biomass of the non-grasses was more sensitive perhaps because they maximally utilize soluble sugar for plant growth, defense and reproduction. Our results showed that different species or functional groups exhibit different NSC-use strategies to cope with drought stress. This study could provide scientific data for predicting future ecosystem responses to extreme drought.
Keywords：
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引用本文
宋琳, 雒文涛, 马望, 何鹏, 梁潇洒, 王正文. 极端干旱对草甸草原优势植物非结构性碳水化合物的影响. 植物生态学报, 2020, 44(6): 669-676. DOI: 10.17521/cjpe.2019.0331
SONG Lin, LUO Wen-Tao, MA Wang, HE Peng, LIANG Xiao-Sa, WANG Zheng-Wen.
植物通过光合作用将CO2和水合成碳水化合物, 碳水化合物不仅是组成细胞结构的主要成分, 而且是新陈代谢过程中重要的能源物质, 对于维持植物体正常的生理活动具有极其重要的作用(Hartmann & Trumbore, 2016)。根据碳水化合物在植物体内的存在形式, 将其划分为结构性碳水化合物(SCs)和非结构性碳水化合物(NSCs)。SCs主要包括纤维素和木质素等多种高分子化合物, 而NSCs主要由可溶性糖(葡萄糖、蔗糖、果糖)和淀粉组成。可溶性糖和淀粉之间可以互相转化, 在植物新陈代谢、抵抗逆境胁迫过程中发挥重要作用(Loewe et al., 2000)。植物NSCs各组分的研究可追溯到20世纪中期, Leloir和Cardini (1953)在对小麦(Triticum aestivum)胚芽的研究中, 首次发现了蔗糖合成酶, 这一重要发现使****开始关注非结构性碳代谢在植物生长发育及代谢中的重要作用。1958年, Hewitt提出了植物NSCs的测定方法, 即分光光度计法。该方法首次使植物NSCs的研究得以定量化。随后的30年中, 植物学家对于NSCs的研究主要以农田生态系统为研究对象, 重点关注植物如何调整NSCs来实现农作物的高产与优质(Raguse & Smith, 1966)。20世纪90年代后期, 随着生态学的快速发展, 定量研究植物NSCs的空间分布规律如何优化植物生产力、影响植被对全球变化的响应与适应成为重要的发展方向。1999年, 生态学家K?rner在探究高山林线的形成过程与机制中, 提出了著名的“碳饥饿”假说。该假说认为, 干旱会打破植物体内碳循环平衡, 影响植物生理生态过程, 最终改变植物群落的结构与功能。在极端干旱胁迫下, 植物会优先保持组织的气孔开合能力以减少蒸腾作用, 但这一过程是以牺牲CO2的吸收为代价, 最终植物为了匹配初级(生长和生殖进程)以及次级代谢(防御化合物的合成)等碳汇活动持续不断的非结构性碳需求, 转为消耗组织内存储的NSCs, 最终因碳收支失衡而饥饿致死。2008年, McDowell等发表综述性评论文章, 将干旱导致植物死亡的机制进行整合, 指出开展干旱对植物NSCs含量动态变化的影响研究将有助于了解极端气候变化对植物生长的影响及其作用机制。综上所述, 目前NSCs动态过程研究仍主要集中于木本植物, 而对于草本植物NSCs的相关研究尚处于起步探索阶段(Dietze et al., 2014; 王晓雨等, 2019)。因此, 对于草本植物NSCs的研究可为预测在全球气候变化背景下草甸草原生态系统结构与功能对极端干旱的响应提供科学参考。
草原生态系统是我国最大的陆地生态系统, 占我国陆地面积的41.7%, 是我国重要的畜牧业生产基地和绿色生态屏障, 在保障国家生态安全、粮食安全乃至全球生态平衡中发挥重要作用(张彬等, 2014)。草原是对降水波动最为敏感的生态系统类型, 极端干旱事件会导致草原生态系统水分失衡, 加剧生态系统的水分胁迫程度, 显著影响草原植物生长和发育(Smith, 2011; Cherwin & Knapp, 2012; 康晓明等, 2015)。近年来, 在全球气候变暖的背景下, 极端干旱事件发生的频率和强度均急剧上升(Jentsch et al., 2009), 对生态系统结构和功能产生严重影响。尽管极端干旱事件通常短暂, 但其对植物群落和生态系统的影响可能会超越多年连续干旱(Jentsch et al., 2004; 张彬等, 2014)。因此, 21世纪以来, 植物如何调整组织内NSCs组成结构应对极端干旱事件的响应已成为生态学家和植物学家关注的热点。
本研究以内蒙古呼伦贝尔草甸草原优势物种为研究对象, 通过控制生长季降水的干旱模拟实验, 探究不同物种与植物功能群NSCs对干旱胁迫的响应机制, 旨在为预测气候变化下草原生态系统结构和功能提供科学依据。
1 材料和方法
1.1 研究区概况
研究地点位于内蒙古自治区呼伦贝尔市额尔古纳市境内的中国科学院沈阳应用生态研究所额尔古纳森林草原过渡带生态系统研究站(50.18° N, 119.38° E), 该区为温带大陆性季风气候, 主要植被类型为草甸草原, 优势物种为狼针草(Stipa baicalensis)、羊草(Leymus chinensis)等, 土壤类型主要为黑钙土, 土层厚度>2 m, 土壤pH为7.0-8.0, 土壤结构多为团块状、粒状含少量细砂。该地区海拔650 m, 年平均气温为-2 ℃, 年降水量为336 mm, 降水分布不均, 主要集中在6-9月份, 雨热同季, 雨量充沛。1.2 实验设计
本研究依托中国科学院沈阳应用生态研究所额尔古纳站的极端干旱实验平台进行。2015年, 选取相对均质(土壤、植被等)并具有典型代表性的地段, 搭建遮雨棚。实验平台采用随机区组设计, 包括两个实验处理: 干旱和对照, 每个处理重复6次, 共12个小区, 干旱处理减少生长季(5-8月) 66%的降水量。小区面积为6 m × 6 m, 相邻小区间隔1 m, 每个小区四周埋有深为1 m的不锈钢隔板以防止小区外水分侧向渗透干扰小区内部。小区中心4 m × 4 m为采样区域, 周边设有1 m缓冲区, 以减小边缘效应。遮雨棚顶部采用田字形钢架的拱形结构, 利于所截降水的排除和减少风的破坏力。拱顶由8块4 m × 1.5 m的钢制遮雨样框拼接而成, 垂直投影面积与小区面积相同。遮雨样框覆有多棱瓦形透明丙烯酸塑料板, 该塑料板具有高透光性、低泛黄度指数, 高UV穿透, 能够显著降低土壤含水率, 又几乎不会降低光合有效辐射(主要为散射光)(Graefe & Sandmann, 2015)。整个遮雨棚采用架高设计, 拱顶最高点距地面2.5 m, 两侧遮雨板尾端距地面60 cm, 有利于保持正常空气流通, 避免温室效应(Luo et al., 2018, 2019)。遮雨棚于每年5月1日安装, 8月31日拆除, 通过设定遮雨棚塑料板条之间距离实现减少66%的降水量, 对照为不加遮雨棚而接受全部自然降雨。1.3 样品采集
2018年8月, 在每个小区内的地上生物量采集区域, 随机设置一个1 m × 1 m的样方, 并将样方划分为4个0.5 m × 0.5 m的小样方, 在斜对角的两个小样方中进行群落物种组成和生物量的调查取样, 在剩余两个0.5 m × 0.5 m的小样方中进行功能性状的观测和叶片采集。实验中获取6种优势植物, 即披针叶野决明(Thermopsis lanceolata)、冷蒿(Artemisia frigida)、寸草(Carex duriuscula)、达乌里芯芭(Cymbaria dahurica)、羊草和狼针草, 并将其分为两个功能群: 禾草(羊草、狼针草)和非禾草(披针叶野决明、冷蒿、寸草、达乌里芯芭)。每个优势种选取10株无明显病虫害的健康植株, 取每株植物从上往下数第2-3片叶片, 带回实验室于105 ℃杀青30 min, 65 ℃烘干至恒质量备用。对照和干旱处理每个小区均采集6种优势植物, 共计72个植物样品。1.4 非结构性碳水化合物成分测定
将植物样品进行烘干粉碎后, 测定植物中可溶性糖和淀粉的含量。具体测定方法为: 称取0.1 g植物样品于10 mL离心管中, 用5 mL 80%乙醇溶液浸提, 在80 ℃沸水中水浴30 min, 冷却至室温后于3 500 r·min-1下离心10 min, 重复提取3次, 转移上清液定容到25 mL比色管用于可溶性糖含量的测定。继续向沉淀中加入2 mL蒸馏水于沸水中糊化10 min, 冷却后加入2 mL 9.2 mol·L-1的HClO4溶液, 搅拌均匀后加4 mL蒸馏水混匀, 于4 000 r·min-1下离心10 min, 将上清液转移至50 mL容量瓶, 继续向沉淀中加入4.6 mol·L-1 HClO4溶液, 搅拌均匀后加5 mL蒸馏水混匀后, 于4 000 r·min-1下离心10 min, 转移上清液, 继续水洗沉淀2次后混合上清液定容至50 mL, 用于淀粉含量的测定(Li et al., 2008)。植物中可溶性糖和淀粉含量的测定采用传统的蒽酮比色法, 并通过紫外分光光度计(620 nm波段; 723S, 上海佑科仪器仪表有限公司, 上海)测定, 其中淀粉含量需要乘以0.9的转化系数。NSCs含量为可溶性糖和淀粉含量的总和。1.5 数据处理
采用R 3.6.1软件对数据进行统计分析。采用混合效应模型方差分析, 对实验处理、物种(功能群)及二者交互作用对植物NSCs含量、淀粉含量、可溶性糖含量和可溶性糖/淀粉的影响进行检验; 利用R软件计算干旱胁迫下不同物种和功能群间NSCs各组分和生物量在干旱处理下的响应比[ln(RR)]和95%的置信区间(95% CI)。2 结果和分析
2.1 干旱处理对遮雨棚内土壤含水量和降水量的影响
1972-2018年降水量正态分布图表明实验对照小区的降水量均在300 mm以上, 发生的频率均在68%以上, 干旱处理后小区的降水量均在200 mm左右, 且发生频率均小于15% (图1A)。干旱处理显著降低了遮雨棚内土壤含水量(图1B)。该联网实验平台的模拟干旱处理开始于2015年, 至今已连续处理4年。综合考虑干旱的持续时间和强度, 干旱处理小区已达到极端干旱水平(历史发生概率小于10%)。图1
新窗口打开|下载原图ZIP|生成PPT图1干旱处理对草甸草原降水量发生概率及土壤含水量的影响(平均值±标准误差)。
Fig. 1Effects of drought treatment on precipitation probability and soil moisture content in a meadow grassland (mean ± SE).
2.2 干旱处理对优势植物生物量及NSCs的影响
干旱处理和物种对生物量无显著的交互作用, 即各物种生物量对干旱处理的响应一致(表1)。物种对干旱的响应机制具有特异性。极端干旱显著降低了各物种的地上生物量, 其中冷蒿响应最显著, 披针叶野决明、寸草和达乌里芯芭次之, 羊草和狼针草响应最弱(表1; 图2)。干旱处理和物种对NSCs含量、淀粉含量、可溶性糖含量以及可溶性糖/淀粉均具有显著的交互作用(p < 0.05; 表1)。如图3所示, 不同植物叶片NSCs含量及其组分对干旱处理的响应不同。干旱显著增加了寸草和狼针草的可溶性糖/淀粉以及可溶性糖的含量和NSCs的含量, 但对淀粉含量无显著影响。干旱显著降低披针叶野决明和达乌里芯芭的可溶性糖/淀粉, 显著降低披针叶野决明的可溶性糖含量和NSCs含量, 但对淀粉含量无显著影响; 干旱处理下达乌里芯芭的可溶性糖含量和NSCs含量未发生变化, 淀粉含量却显著增加; 干旱未引起冷蒿和羊草可溶性糖/淀粉和羊草的可溶性糖含量和淀粉含量的变化, 却显著提高了冷蒿的可溶性糖含量、淀粉含量和NSCs含量。Table 1
表1
表1干旱处理、物种/功能群及其交互作用对草甸草原优势植物生物量和植物非结构性碳水化合物(NSCs)各组分含量及其比值影响的混合效应模型结果
Table 1
| 生物量 Biomass | 可溶性糖 SS | 淀粉 ST | 可溶性糖/淀粉 SS/ST | NSCs | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| F | p | F | p | F | p | F | p | F | p | |
| 物种 Species | ||||||||||
| 干旱 Drought (D) | 2.195 | 0.146 | 33.645 | <0.001 | 0.216 | 0.645 | 12.937 | 0.001 | 27.713 | <0.001 |
| 物种 Species (S) | 28.212 | <0.001 | 36.017 | <0.001 | 8.115 | <0.001 | 47.012 | <0.001 | 20.478 | <0.001 |
| 干旱×物种 D × S | 0.558 | 0.732 | 25.508 | <0.001 | 3.321 | 0.012 | 13.872 | <0.001 | 19.880 | <0.001 |
| 功能群 Functional group | ||||||||||
| 干旱 Drought (D) | 0.960 | 0.332 | 5.528 | 0.023 | 0.130 | 0.720 | 2.144 | 0.149 | 6.627 | 0.013 |
| 功能群 Functional (F) | 26.055 | <0.001 | 1.510 | 0.225 | 0.459 | 0.501 | 0.412 | 0.524 | 2.185 | 0.145 |
| 干旱×功能群 D × F | 0.154 | 0.696 | 0.014 | 0.905 | 6.236 | 0.016 | 0.326 | 0.571 | 0.280 | 0.599 |
新窗口打开|下载CSV
图2
新窗口打开|下载原图ZIP|生成PPT图2草甸草原物种和功能群植物生物量对干旱处理的响应。
Grass, 禾草功能群; Non-grass, 非禾草功能群。其中响应比为干旱与对照小区中非结构性碳水化合物(NSCs)的比值, 水平误差条表示95%的置信区间, 皆由R语言中的“metaphor”包计算得出。圆代表物种, 方块代表功能群; 实心表示响应显著(p < 0.05), 空心表示响应不显著。
Fig. 2Response ratio of the biomass of six herbaceous species and different plant functional groups to drought in a meadow grassland. T.l., Thermopsis lanceolata; A.f., Artemisia frigida; C.d., Carex duriuscula; Cy.d., Cymbaria dahurica; L.c., Leymus chinensis; S.b., Stipa baicalensis; Grass, grass functional group; Non-grass, non-grass functional group.
The response ratio is biomass (drought)/biomass (control), the horizontal error bars represent the 95% confidence interval, which are calculated by “metaphor” in R. Solid circles indicate the significant responses of herbaceous plant species level nonstructural carbohydrates (NSCs) to drought (p < 0.05), while the hollow circles represent no significant response. Solid squares represent significant response of NSCs in different functional groups to drought, while hollow squares represent no significant response.
图3
新窗口打开|下载原图ZIP|生成PPT图3草甸草原不同物种和功能群植物叶片可溶性糖含量(A)、淀粉含量(B)、可溶性糖/淀粉(C)及非结构性碳水化合物(NSCs) 含量(D)对干旱的响应。
水平误差条表示95%的置信区间。圆代表物种, 方块代表功能群; 实心表示响应显著(p < 0.05), 空心表示响应不显著。
Fig. 3Response ratio of soluble sugar content (A), starch concentrations content (B), soluble sugar/starch ratios (C) and nonstructural carbohydrates (NSCs) content (D) in leaves of six herbaceous species and two plant functional groups to drought treatments. T.l., Thermopsis lanceolata; A.f., Artemisia frigida; C.d., Carex duriuscula; Cy.d., Cymbaria dahurica; L.c., Leymus chinensis; S.b., Stipa baicalensis; Grass, grass functional group; Non-grass, non-grass functional group.
The horizontal error bars represent the 95% confidence interval. Solid circles indicate the significant responses of herbaceous plant species level NSCs to drought (p < 0.05), while the hollow circles represent no significant response. Solid squares represent significant response of NSCs in different functional groups to drought, while hollow squares represent no significant response.
2.3 干旱处理对不同植物功能群生物量及NSCs含量的影响
干旱处理和植物功能群对生物量的影响无显著交互作用, 表明干旱处理对各功能群生物量的影响一致(表1)。干旱显著降低了两个功能群的地上生物量, 其中非禾草功能群的响应程度高于禾草(图2)。极端干旱处理和功能群的交互作用对淀粉含量的影响显著, 但对NSCs含量、可溶性糖/淀粉及可溶性糖含量的影响不显著(表1)。对照和干旱处理间的可溶性糖含量和NSCs含量具有显著性差异, 但淀粉含量和可溶性糖/淀粉无显著差异(p > 0.05)。不同功能群NSCs含量、淀粉含量、可溶性糖含量及可溶性糖/ 淀粉无显著性差异(图3)。干旱显著增加了禾草功能群的淀粉含量和可溶性糖/淀粉, 但对可溶性糖含量和NSCs含量无显著影响; 相反, 干旱显著增加了非禾草功能群的可溶性糖含量和NSCs的含量, 但对淀粉含量和可溶性糖/淀粉无显著影响(图3)。3 讨论
3.1 干旱对草原优势物种叶片NSCs的影响
植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化。植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(潘庆民等, 2002; 郑云普等, 2014)。面对极端干旱事件, 植物通常在体内存储一定量的NSCs以提供更多的能量来抵御水分胁迫, 维持自身生命活动(郑云普等, 2014)。本研究发现, 极端干旱胁迫对NSCs的影响具有明显的物种特异性, 不同物种采取不同的碳利用策略来适应、抵御水分胁迫。由于构成某一群落的物种具有不同的生理生化过程及生物学特性, 植物大小、资源利用方式及对水分胁迫的响应等方面均存在显著差异(赵桂仿等, 2003; McInerny & Etienne, 2012)。例如, 植物群落内羊草和冷蒿性状特征对干旱的响应不同, 羊草性状相对稳定, 而冷蒿性状会随水分的变化而变化(Zhou et al., 2019)。在长期的演化过程中, 植物种内、种间竞争等关系会引起生态位分化, 这种生态位分化使具有不同生态型或遗传多样性的物种在干旱胁迫下对NSCs的利用策略不同(周淑荣和张大勇, 2006; 彭文俊和王晓鸣, 2016), 如披针叶野决明、冷蒿和狼针草的NSCs含量对干旱的响应程度不同(图4)。因此, 不同生态位上的物种生活方式、利用资源的形式等方面均有差异(王云龙等, 2004), 为了保证自身的生长发育, 不同物种必须通过调节体内NSCs的含量来应对干旱胁迫, 对于草原优势物种干旱胁迫下NSCs响应不同的响应有助于为利用生态位模型预测草原物种分化和物种生态位建模提供数据支持。3.2 干旱对草原不同植物功能群叶片NSCs影响
研究表明, 草原植物的NSCs代谢过程对极端干旱的响应不仅具有物种特异性, 在不同功能群也存在明显差异, 本研究发现禾草功能群NSCs含量和可溶性糖含量对干旱胁迫响应不敏感, 但干旱胁迫显著增加了淀粉含量。相反, 非禾草的NSCs含量和可溶性糖含量在干旱胁迫下显著增加, 而淀粉含量无显著变化。这说明不同功能群植物在应对干旱胁迫时对NSCs各组分的调控机制存在差异。逆境胁迫下, 禾草功能群对非结构性碳水化合物的存储需求高于非禾草功能群。相反, 非禾草功能群组织中的光合产物(NSCs)主要以可溶性糖的形式存在, 可直接为生长、繁殖、防御等活动提供能量。此外, 在干旱胁迫下, 由于木质部结构差异, 非禾草植物对水分运输的调节需求高于禾草植物(王云龙等, 2004)。因此, 非禾草组织中的NSCs主要以可溶性糖而非淀粉的形式存在。Ford和Wilson (1981)研究发现可溶性糖与植物的渗透调节能力存在直接关系, 是植物长期忍受干旱环境的重要渗透调节物质, 可根据土壤水分等情况调节植物细胞渗透势, 使植物在缺水情况下能够进行正常的生理过程来适应干旱胁迫(Iannucci et al., 2002)。Li等(2013)研究发现, 在干旱环境下, 植物为满足渗透调节等生理需求会主动提高NSCs及各组分的含量。不同植物功能群的渗透调节和抗旱能力的差异会决定植物的非结构性碳水化合物代谢过程。在面临极端干旱时, 不同功能群物种将采取不同的碳利用策略来适应胁迫(Chen, 2008; Chen et al., 2013)。禾草优先合成淀粉, 以储存更多的能量来满足干旱后的再生长, 其生物量对干旱的响应不敏感。同时, 一旦发生更为严峻的干旱胁迫, 组织中的淀粉可立即转化为糖作为渗透底物促进木质部中水分的传导。NSCs作为渗透调节底物的功能已被前人所证实(王云龙等, 2004)。相反, 非禾草将同化的光合产物以可溶性糖的形式存储, 直接用于抵抗环境胁迫, 维持正常生理代谢活动。保持一定含量的可溶性糖水平有利于维持细胞渗透压, 保持细胞水分充足, 进而提高水分传输效率(Dietze et al., 2014)。
4 结论
植物通过光合作用合成的NSCs不仅为其代谢活动提供能量, 还在一定程度上反映了该植物对外界环境的适应策略。然而, 目前对干旱影响非结构性碳水化合物动态的研究主要集中于木本植物, 而对草本植物的研究尚显薄弱。本研究通过测定不同干旱处理下草甸草原植物叶片NSCs及各组分的含量, 探讨了草本植物对干旱胁迫的生理适应机制, 发现不同物种和功能群通过采取不同的NSCs利用策略以应对干旱。禾草功能群在干旱胁迫下主要将光合产物以淀粉的形式进行存储以保证生存和干旱后的组织修复。而非禾草功能群通过提高可溶性糖的含量来维持植物生长及水分传输。本研究揭示了草甸草原植物在干旱条件下的碳代谢和生长适应策略, 阐明了物种和功能群间对NSCs利用的生态位分化及其生理学基础, 对诠释物种共存机制和群落构建法则具有重要意义。
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Non-structural carbohydrates (NSCs) are an important energy source for the metabolism of plants. The size of the NSC pool is likely to mirror the overall carbon supply status and its dynamics strongly influences physiological processes in plants. In order to predict the response and adaptation of trees to climate change, this review summarized the current understanding of NSC pool in trees, and mainly focused on its seasonal and spatial variation for analyzing the relationships between environmental factors and NSC allocation. Moreover, the response and adaptation strategies of NSC pool in trees to climate change were also discussed. Finally, some suggestions were proposed for the potential study orientation of NSC pool in trees in future climate conditions.
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... 在面临极端干旱时, 不同功能群物种将采取不同的碳利用策略来适应胁迫(
Comparing physiological responses of two dominant grass species to nitrogen addition in Xilin River Basin of China
1
2005
... 在面临极端干旱时, 不同功能群物种将采取不同的碳利用策略来适应胁迫(
Unexpected patterns of sensitivity to drought in three semi-arid grasslands
1
2012
... 草原生态系统是我国最大的陆地生态系统, 占我国陆地面积的41.7%, 是我国重要的畜牧业生产基地和绿色生态屏障, 在保障国家生态安全、粮食安全乃至全球生态平衡中发挥重要作用(
Nonstructural carbon in woody plants
2
2014
... 植物通过光合作用将CO2和水合成碳水化合物, 碳水化合物不仅是组成细胞结构的主要成分, 而且是新陈代谢过程中重要的能源物质, 对于维持植物体正常的生理活动具有极其重要的作用(
... 在面临极端干旱时, 不同功能群物种将采取不同的碳利用策略来适应胁迫(
Hydrologic regulation of plant rooting depth
2017
Changes in levels of solutes during osmotic adjustment to water-stress in leaves of four tropical pasture species
1
1981
... 研究表明, 草原植物的NSCs代谢过程对极端干旱的响应不仅具有物种特异性, 在不同功能群也存在明显差异, 本研究发现禾草功能群NSCs含量和可溶性糖含量对干旱胁迫响应不敏感, 但干旱胁迫显著增加了淀粉含量.相反, 非禾草的NSCs含量和可溶性糖含量在干旱胁迫下显著增加, 而淀粉含量无显著变化.这说明不同功能群植物在应对干旱胁迫时对NSCs各组分的调控机制存在差异.逆境胁迫下, 禾草功能群对非结构性碳水化合物的存储需求高于非禾草功能群.相反, 非禾草功能群组织中的光合产物(NSCs)主要以可溶性糖的形式存在, 可直接为生长、繁殖、防御等活动提供能量.此外, 在干旱胁迫下, 由于木质部结构差异, 非禾草植物对水分运输的调节需求高于禾草植物(
Shortwave radiation transfer through a plant canopy covered by single and double layers of plastic
1
2015
... 本研究依托中国科学院沈阳应用生态研究所额尔古纳站的极端干旱实验平台进行.2015年, 选取相对均质(土壤、植被等)并具有典型代表性的地段, 搭建遮雨棚.实验平台采用随机区组设计, 包括两个实验处理: 干旱和对照, 每个处理重复6次, 共12个小区, 干旱处理减少生长季(5-8月) 66%的降水量.小区面积为6 m × 6 m, 相邻小区间隔1 m, 每个小区四周埋有深为1 m的不锈钢隔板以防止小区外水分侧向渗透干扰小区内部.小区中心4 m × 4 m为采样区域, 周边设有1 m缓冲区, 以减小边缘效应.遮雨棚顶部采用田字形钢架的拱形结构, 利于所截降水的排除和减少风的破坏力.拱顶由8块4 m × 1.5 m的钢制遮雨样框拼接而成, 垂直投影面积与小区面积相同.遮雨样框覆有多棱瓦形透明丙烯酸塑料板, 该塑料板具有高透光性、低泛黄度指数, 高UV穿透, 能够显著降低土壤含水率, 又几乎不会降低光合有效辐射(主要为散射光)(
Understanding the roles of nonstructural carbohydrates in forest trees-from what we can measure to what we want to know
1
2016
... 植物通过光合作用将CO2和水合成碳水化合物, 碳水化合物不仅是组成细胞结构的主要成分, 而且是新陈代谢过程中重要的能源物质, 对于维持植物体正常的生理活动具有极其重要的作用(
Spectrophotometric determination of total carbohydrate
1958
Water deficit effects on osmotic adjustment and solute accumulation in leaves of annual clovers
1
2002
... 研究表明, 草原植物的NSCs代谢过程对极端干旱的响应不仅具有物种特异性, 在不同功能群也存在明显差异, 本研究发现禾草功能群NSCs含量和可溶性糖含量对干旱胁迫响应不敏感, 但干旱胁迫显著增加了淀粉含量.相反, 非禾草的NSCs含量和可溶性糖含量在干旱胁迫下显著增加, 而淀粉含量无显著变化.这说明不同功能群植物在应对干旱胁迫时对NSCs各组分的调控机制存在差异.逆境胁迫下, 禾草功能群对非结构性碳水化合物的存储需求高于非禾草功能群.相反, 非禾草功能群组织中的光合产物(NSCs)主要以可溶性糖的形式存在, 可直接为生长、繁殖、防御等活动提供能量.此外, 在干旱胁迫下, 由于木质部结构差异, 非禾草植物对水分运输的调节需求高于禾草植物(
Beyond gradual warming: extreme weather events alter flower phenology of European grassland and heath species
2
2009
... 草原生态系统是我国最大的陆地生态系统, 占我国陆地面积的41.7%, 是我国重要的畜牧业生产基地和绿色生态屏障, 在保障国家生态安全、粮食安全乃至全球生态平衡中发挥重要作用(
... ), 对生态系统结构和功能产生严重影响.尽管极端干旱事件通常短暂, 但其对植物群落和生态系统的影响可能会超越多年连续干旱(
极端干旱对内蒙古羊草草原水分平衡的影响
1
2015
... 草原生态系统是我国最大的陆地生态系统, 占我国陆地面积的41.7%, 是我国重要的畜牧业生产基地和绿色生态屏障, 在保障国家生态安全、粮食安全乃至全球生态平衡中发挥重要作用(
极端干旱对内蒙古羊草草原水分平衡的影响
1
2015
... 草原生态系统是我国最大的陆地生态系统, 占我国陆地面积的41.7%, 是我国重要的畜牧业生产基地和绿色生态屏障, 在保障国家生态安全、粮食安全乃至全球生态平衡中发挥重要作用(
Alpine Plant Life: Functional Plant Ecology of High Mountain Ecosystems
1999
The biosynthesis of sucrose-correction
1
1955
... 植物通过光合作用将CO2和水合成碳水化合物, 碳水化合物不仅是组成细胞结构的主要成分, 而且是新陈代谢过程中重要的能源物质, 对于维持植物体正常的生理活动具有极其重要的作用(
Responses of leaf nitrogen and mobile carbohydrates in different Quercus species/provenances to moderate climate changes
1
2013
... 研究表明, 草原植物的NSCs代谢过程对极端干旱的响应不仅具有物种特异性, 在不同功能群也存在明显差异, 本研究发现禾草功能群NSCs含量和可溶性糖含量对干旱胁迫响应不敏感, 但干旱胁迫显著增加了淀粉含量.相反, 非禾草的NSCs含量和可溶性糖含量在干旱胁迫下显著增加, 而淀粉含量无显著变化.这说明不同功能群植物在应对干旱胁迫时对NSCs各组分的调控机制存在差异.逆境胁迫下, 禾草功能群对非结构性碳水化合物的存储需求高于非禾草功能群.相反, 非禾草功能群组织中的光合产物(NSCs)主要以可溶性糖的形式存在, 可直接为生长、繁殖、防御等活动提供能量.此外, 在干旱胁迫下, 由于木质部结构差异, 非禾草植物对水分运输的调节需求高于禾草植物(
Mobile carbohydrates in Himalayan treeline trees I. Evidence for carbon gain limitation but not for growth limitation
1
2008
... 将植物样品进行烘干粉碎后, 测定植物中可溶性糖和淀粉的含量.具体测定方法为: 称取0.1 g植物样品于10 mL离心管中, 用5 mL 80%乙醇溶液浸提, 在80 ℃沸水中水浴30 min, 冷却至室温后于3 500 r·min-1下离心10 min, 重复提取3次, 转移上清液定容到25 mL比色管用于可溶性糖含量的测定.继续向沉淀中加入2 mL蒸馏水于沸水中糊化10 min, 冷却后加入2 mL 9.2 mol·L-1的HClO4溶液, 搅拌均匀后加4 mL蒸馏水混匀, 于4 000 r·min-1下离心10 min, 将上清液转移至50 mL容量瓶, 继续向沉淀中加入4.6 mol·L-1 HClO4溶液, 搅拌均匀后加5 mL蒸馏水混匀后, 于4 000 r·min-1下离心10 min, 转移上清液, 继续水洗沉淀2次后混合上清液定容至50 mL, 用于淀粉含量的测定(
Mycorrhiza formation and elevated CO2 both increase the capacity for sucrose synthesis in source leaves of spruce and aspen
1
2000
... 植物通过光合作用将CO2和水合成碳水化合物, 碳水化合物不仅是组成细胞结构的主要成分, 而且是新陈代谢过程中重要的能源物质, 对于维持植物体正常的生理活动具有极其重要的作用(
Long term experimental drought alters community plant trait variation, not trait means, across three semiarid grasslands
1
2019
... 本研究依托中国科学院沈阳应用生态研究所额尔古纳站的极端干旱实验平台进行.2015年, 选取相对均质(土壤、植被等)并具有典型代表性的地段, 搭建遮雨棚.实验平台采用随机区组设计, 包括两个实验处理: 干旱和对照, 每个处理重复6次, 共12个小区, 干旱处理减少生长季(5-8月) 66%的降水量.小区面积为6 m × 6 m, 相邻小区间隔1 m, 每个小区四周埋有深为1 m的不锈钢隔板以防止小区外水分侧向渗透干扰小区内部.小区中心4 m × 4 m为采样区域, 周边设有1 m缓冲区, 以减小边缘效应.遮雨棚顶部采用田字形钢架的拱形结构, 利于所截降水的排除和减少风的破坏力.拱顶由8块4 m × 1.5 m的钢制遮雨样框拼接而成, 垂直投影面积与小区面积相同.遮雨样框覆有多棱瓦形透明丙烯酸塑料板, 该塑料板具有高透光性、低泛黄度指数, 高UV穿透, 能够显著降低土壤含水率, 又几乎不会降低光合有效辐射(主要为散射光)(
Differential responses of canopy nutrients to experimental drought along a natural aridity gradient
1
2018
... 本研究依托中国科学院沈阳应用生态研究所额尔古纳站的极端干旱实验平台进行.2015年, 选取相对均质(土壤、植被等)并具有典型代表性的地段, 搭建遮雨棚.实验平台采用随机区组设计, 包括两个实验处理: 干旱和对照, 每个处理重复6次, 共12个小区, 干旱处理减少生长季(5-8月) 66%的降水量.小区面积为6 m × 6 m, 相邻小区间隔1 m, 每个小区四周埋有深为1 m的不锈钢隔板以防止小区外水分侧向渗透干扰小区内部.小区中心4 m × 4 m为采样区域, 周边设有1 m缓冲区, 以减小边缘效应.遮雨棚顶部采用田字形钢架的拱形结构, 利于所截降水的排除和减少风的破坏力.拱顶由8块4 m × 1.5 m的钢制遮雨样框拼接而成, 垂直投影面积与小区面积相同.遮雨样框覆有多棱瓦形透明丙烯酸塑料板, 该塑料板具有高透光性、低泛黄度指数, 高UV穿透, 能够显著降低土壤含水率, 又几乎不会降低光合有效辐射(主要为散射光)(
Mechanisms of plant survival and mortality during drought: Why do some plants survive while others succumb to drought?
2008
Pitch the niche-taking responsibility for the concepts we use in ecology and species distribution modelling
1
2012
... 植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化.植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(
植物非结构性贮藏碳水化合物的生理生态学研究进展
1
2002
... 植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化.植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(
植物非结构性贮藏碳水化合物的生理生态学研究进展
1
2002
... 植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化.植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(
生态位概念和内涵的发展及其在生态学中的定位
1
2016
... 植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化.植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(
生态位概念和内涵的发展及其在生态学中的定位
1
2016
... 植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化.植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(
How ecologists define drought, and why we should do better
2019
An ecological perspective on extreme climatic events: a synthetic definition and framework to guide future research
1
2011
... 草原生态系统是我国最大的陆地生态系统, 占我国陆地面积的41.7%, 是我国重要的畜牧业生产基地和绿色生态屏障, 在保障国家生态安全、粮食安全乃至全球生态平衡中发挥重要作用(
Regulation of water loss in populations of Populus trichocarpa: the role of stomatal control in preventing xylem cavitation
1999
Strategic niche management from a business perspective: taking cleaner vehicle technologies from prototype to series production
2014
高寒草甸不同草地类型功能群多样性及组成对植物群落生产力的影响
2004
高寒草甸不同草地类型功能群多样性及组成对植物群落生产力的影响
2004
半干旱典型草原养分添加对优势物种叶片氮磷及非结构性碳水化合物含量的影响
2014
半干旱典型草原养分添加对优势物种叶片氮磷及非结构性碳水化合物含量的影响
2014
长白山阔叶红松林3个主要树种的非结构性碳储存特征
1
2019
... 植物通过光合作用将CO2和水合成碳水化合物, 碳水化合物不仅是组成细胞结构的主要成分, 而且是新陈代谢过程中重要的能源物质, 对于维持植物体正常的生理活动具有极其重要的作用(
长白山阔叶红松林3个主要树种的非结构性碳储存特征
1
2019
... 植物通过光合作用将CO2和水合成碳水化合物, 碳水化合物不仅是组成细胞结构的主要成分, 而且是新陈代谢过程中重要的能源物质, 对于维持植物体正常的生理活动具有极其重要的作用(
水分胁迫对羊草光合产物分配及其气体交换特征的影响
3
2004
... 植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化.植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(
... 研究表明, 草原植物的NSCs代谢过程对极端干旱的响应不仅具有物种特异性, 在不同功能群也存在明显差异, 本研究发现禾草功能群NSCs含量和可溶性糖含量对干旱胁迫响应不敏感, 但干旱胁迫显著增加了淀粉含量.相反, 非禾草的NSCs含量和可溶性糖含量在干旱胁迫下显著增加, 而淀粉含量无显著变化.这说明不同功能群植物在应对干旱胁迫时对NSCs各组分的调控机制存在差异.逆境胁迫下, 禾草功能群对非结构性碳水化合物的存储需求高于非禾草功能群.相反, 非禾草功能群组织中的光合产物(NSCs)主要以可溶性糖的形式存在, 可直接为生长、繁殖、防御等活动提供能量.此外, 在干旱胁迫下, 由于木质部结构差异, 非禾草植物对水分运输的调节需求高于禾草植物(
... 在面临极端干旱时, 不同功能群物种将采取不同的碳利用策略来适应胁迫(
水分胁迫对羊草光合产物分配及其气体交换特征的影响
3
2004
... 植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化.植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(
... 研究表明, 草原植物的NSCs代谢过程对极端干旱的响应不仅具有物种特异性, 在不同功能群也存在明显差异, 本研究发现禾草功能群NSCs含量和可溶性糖含量对干旱胁迫响应不敏感, 但干旱胁迫显著增加了淀粉含量.相反, 非禾草的NSCs含量和可溶性糖含量在干旱胁迫下显著增加, 而淀粉含量无显著变化.这说明不同功能群植物在应对干旱胁迫时对NSCs各组分的调控机制存在差异.逆境胁迫下, 禾草功能群对非结构性碳水化合物的存储需求高于非禾草功能群.相反, 非禾草功能群组织中的光合产物(NSCs)主要以可溶性糖的形式存在, 可直接为生长、繁殖、防御等活动提供能量.此外, 在干旱胁迫下, 由于木质部结构差异, 非禾草植物对水分运输的调节需求高于禾草植物(
... 在面临极端干旱时, 不同功能群物种将采取不同的碳利用策略来适应胁迫(
极端降水和极端干旱事件对草原生态系统的影响
2
2014
... 草原生态系统是我国最大的陆地生态系统, 占我国陆地面积的41.7%, 是我国重要的畜牧业生产基地和绿色生态屏障, 在保障国家生态安全、粮食安全乃至全球生态平衡中发挥重要作用(
... ;
极端降水和极端干旱事件对草原生态系统的影响
2
2014
... 草原生态系统是我国最大的陆地生态系统, 占我国陆地面积的41.7%, 是我国重要的畜牧业生产基地和绿色生态屏障, 在保障国家生态安全、粮食安全乃至全球生态平衡中发挥重要作用(
... ;
植物种群分子进化中对生境的适应
1
2003
... 植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化.植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(
植物种群分子进化中对生境的适应
1
2003
... 植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化.植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(
木本植物非结构性碳水化合物变化及其影响因子研究进展
2
2014
... 植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化.植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(
... ).面对极端干旱事件, 植物通常在体内存储一定量的NSCs以提供更多的能量来抵御水分胁迫, 维持自身生命活动(
木本植物非结构性碳水化合物变化及其影响因子研究进展
2
2014
... 植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化.植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(
... ).面对极端干旱事件, 植物通常在体内存储一定量的NSCs以提供更多的能量来抵御水分胁迫, 维持自身生命活动(
The response of root traits to precipitation change of herbaceous species in temperate steppes
1
2019
... 植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化.植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(
群落生态学的中性理论
1
2006
... 植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化.植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(
群落生态学的中性理论
1
2006
... 植物对干旱的适应性是指植物主动调节自身生理生态特征(包括碳利用策略)来适应水分环境变化的能力, 而植物对水分胁迫的响应是指干旱胁迫会导致植物的存活空间或空间分布格局发生变化.植物体内NSCs及其组分是植物生长和发育等一系列生理活动的重要能源物质, 其在植物体内含量的变化不仅能反映植物体内碳吸收和碳消耗等生理活动状况, 同时也能反映植物对干旱胁迫的响应(
高寒草甸不同类型草地群落特征及优势种植物生态位差异
2016
高寒草甸不同类型草地群落特征及优势种植物生态位差异
2016
