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Alpine grassland in the Qingzang Plateau: Pattern and process

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植物生态学报 2021, 45 (5): 00-00 DOI: 10.17521/cjpe.2021.0099
Chinese Journal of Plant Ecology http://www.plant-ecology.com
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收稿日期Received: 2021-03-19 接受日期Accepted: 2021-05-09
基金项目: 第二次青藏高原综合科学考察研究项目(2019QZKK0405)和国家自然科学基金(41871040)Supported by the Second Tibetan Plateau Sci-
entific Expedition and Research Program (2019QZKK0405), and the National Natural Science Foundation of China (41871040).
* E-mail: sunjian@itpcas.ac.cn
青藏高原高寒草地: 格局与过程
1,2,3* 刘国华2,3
1中国科学院青藏高原研究所青藏高原地球系统与资源环境国家重点实验室, 北京 100101; 2中国科学院生态环境研究中心城市与区域生态学国家重
点实验室, 北京 100085;
3中国科学院大学资源与环境学院, 北京 100190
孙建, 刘国华 (2021). 青藏高原高寒草地: 格局与过程. 植物生态学报, 45, 00-00. DOI: 10.17521/cjpe.2021.0099
Alpine grassland in the Qingzang Plateau: pattern and process
SUN Jian1,2,3* and LIU Guo-Hua2,3
1State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE), Institute of Tibetan Plateau Research, Chinese Academy of
Sciences, Beijing 100101, China; 2State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy
of Sciences, Beijing 100085, China; and 3College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China
Sun J, Liu GH (2021). Alpine grassland in the Qingzang Plateau: pattern and process. Chinese Journal of Plant Ecology, 45, 00-00. DOI:
10.17521/cjpe.2021.0099
随着全球变化问题的凸显, 如全球温度升高、
人类活动加剧、极端气候频发、大气成分改变以及
海洋水质恶化等, 越来越多的研究者开始关注气候
变化对全球生物地理格局和过程的影响(Goldblum
& Carrier, 2017)。青藏高原是世界上海拔最高、面
积最大的高原, 约占中国陆地国土总面积的26%,
平均海拔4 000 m以上, 被称为世界屋脊” (孙建等,
2019), 是高寒草地格局与过程研究的天然实验室,
具有典型的水平地带性。喜马拉雅山、喀喇昆仑山
和昆仑山, 阻挡了西风对青藏高原的水汽输送,
高原抽气系统的影响下, 印度季风和东亚季风带
来的水汽被源源不断地抽提到高海拔的青藏高原,
从第一阶梯开始, 水汽不断地消耗, 因此在高原面
, 形成了从东南到西北递减的降水梯度(郭柯和
郑度, 2002)。受降水梯度的长期影响, 植被类型分
异明显, 形成了森林、灌丛、高寒草甸、高寒草原
和高寒荒漠草原的植被地理格局(1)高寒草地作
为青藏高原主要的生态系统, 对畜牧业发展起到重
要的支撑作用(Sun et al., 2021), 发挥着极其重要的
气候调节和水源涵养等生态系统功能, 是我国重要
的战略资源储备要地和生态安全屏障(姚檀栋等,
2017)由于青藏高原高寒、生长周期短和土壤贫瘠
的特点, 高寒草地对环境的变化极为敏感。
目前, 青藏高原整体呈变暖趋势, 导致青藏高
原冰川融化, 湖泊增加, 湖泊总数从由1990年的868
个增加到2015 年的1 207 , 湖泊总水面面积从
38 823.3 km2增加到48 793.0 km2 (Sun et al., 2018)
此外, 持续减少的冻土活动层厚度和增加的大气氮
沉降速率(Wu & Zhang, 2010), 以及不断增加的人
类活动, 如围栏和放牧等生态系统管理措施也在改
变和修饰着高寒生态系统(Sun et al., 2020)。这些全
球变化的主要表现形式必将对高寒植被地理格局和
过程产生深刻的影响, 理解其中的功能变化和过程
机制, 有助于我们深入理解高寒草地的分布变化和
发展趋势, 以推进青藏高原生态安全屏障建设,
撑高原可持续发展, 这对国家生态文明建设等方面
具有重要的参考价值。值得深度关注的是, 大量的
研究都考虑自然过程, 忽略了无处不在的放牧利用
方式和基本覆盖全域的围栏管理措施带来的影响,
导致真实的格局、过程和机制很难被深刻地理解或
阐明。因此建议未来高寒草地格局与过程研究,
该综合考虑人类活动要素。
近年来, 国内外学者围绕全球变化背景下的高
寒草地生态系统格局和过程等主题开展了大量工作,
并已经取得了重要进展(2)。技术层面上, 随着测
试手段的提升, 研究呈现技术多样性, 如卫星遥感、
模型模拟、大尺度样带调查、无人机航拍和定位观
2 植物生态学报 Chinese Journal of Plant Ecology 2021, 45 (5): 00-00
www.plant-ecology.com
1 青藏高原季风与主要山脉格局(A)、多年平均年降水量(B)、多年平均气温(C)和植被类型地理格局(D)
Fig. 1 Pattern of monsoon and main mountains (A), mean annual precipitation (B), perennial mean air temperature (C), geographi-
cal pattern of vegetation types in the Qingzang Plateau (D).
2 青藏高原高寒草地生态系统格局与过程研究概念图。
Fig. 2 Mind map of alpine grassland ecosystem pattern and process on the Qingzang Plateau.
孙建等: 青藏高原高寒草地: 格局与过程 3
DOI: 10.17521/cjpe.2021.0099
; 研究尺度从区域、景观、生态系统和群落尺度
发展到微观分子和基因组层面的研究等; 观测指标
更为完整, 从基础指标观测完善为涵盖水分、土壤、
生物、水域和气候五大观测指标体系; 驱动因素考
虑逐渐全面, 涵盖干旱、冻融、鼠害、杂草入侵、
放牧和围栏管理等驱动过程, 从环境因素发展到自
然因素和人类活动以及整个生境对高寒生态系统影
响的考虑; 关注点从营养级、食物网、地上和地下
独立过程发展到整个生态系统各个过程地上和地下
的链接; 研究机理更为深入, 从单纯的植物和植被
分类, 植被地理格局与环境要素的关联, 发展到植
被结构、功能、特征和过程的地理格局与环境要素
的关联和响应与适应机制方面。新的时期、新的技
术和理论, 为青藏高原植被地理格局和过程研究提
供了新的研究方向。
基于以上论述的意义和目的, 我们组织了
藏高原高寒草地: 格局与过程专辑, 以期推进后续
的相关研究。本专辑收录了13篇文章, 内容涉及基
于样带尺度上的地上生态系统多功能性, 土壤酶活
性和有机质化学组成变化格局与成因, 以及在降水
梯度对高寒草地养分限制的机制探讨, 同时对海拔
梯度上的植物功能性状也进行了梳理。基于站点的
观测研究探讨了土壤营养、土壤微生物、植物多样
性等动态变化与成因, 涉及人工草地、天然草地、
鼠兔干扰草地和退化草地等不同草地类型和草地利
用方式。
在多功能性方面, 基于青藏高原地区115 个样
点进行了草地群落结构和土壤属性等要素的样带调
, 综合植物地上生物量, 叶片碳、氮和磷含量等参
数计算多功能性, 讨论了青藏高原高寒草地地上生
态系统功能与环境要素关系(王毅等, 2021), 并针对
碳积累速率对生态系统多功能性开展了进一步剖析
(孙建等, 2021), 发现土壤微生物生物量氮和群落地
上碳积累速率在调控高寒草地生态系统多功能方面
发挥重要作用。此外, 宗宁等(2021)通过在藏北降水
梯度下高寒草甸、高寒草甸草原、高寒草原和高寒
荒漠草原的氮磷养分添加试验, 发现随着降水量降
, 高寒草地养分限制模式从氮限制逐渐过渡到氮
磷共同限制。颇具实际生产指导的意义在于, 利用
养分添加恢复不同类型退化高寒草地时, 应将氮磷
限制模式的差异考虑进去。此外, 也开展了不同草
地类型土壤酶活性格局与过程等相关研究(汪子微
, 2021), 马书琴等(2021)研究发现不同高寒草地
类型间碳循环酶、磷循环酶和两种氮循环酶(芳香氨
基酶和亚硝酸盐还原酶)活性差异显著, 且土壤有
机质、微生物数量和氮含量等是影响高寒草地生态
系统土壤酶活性的关键因子。该研究在国内较早地
开展热裂解气质联用技术(Py-GC/MS)分析, 并比较
不同类型草地土壤有机质化学组成, 发现高寒草地
类型和土壤有机质化学是影响高寒草地土壤蛋白酶
活性的重要因素, 而对土壤脲酶活性的影响均未达
到显著水平。海拔梯度上, 向响等(2021)开展了青海
湖流域群落水平植物功能性状的影响, 认为随海拔
变化的热量和深层土壤养分含量是群落水平植物功
能性状变化的主要影响因子, 特别是针对热量的理
, 可为今后相关研究提供理论参考。
针对退化草地, 董利军等(2021)开展了若尔盖
湿地高寒草甸退化过程中土壤有机碳含量变化及成
因分析, 认为土壤含水量的降低导致的植物碳潜在
输入量的降低是若尔盖湿地高寒草甸退化过程中土
壤有机碳含量下降的主要原因。罗明没等(2021)
过野外原位试验和水位恢复梯度的设置, 揭示短期
水位恢复并没有改变原核微生物的α多样性, 土壤
pH有机碳、全氮等控制了退化泥炭地原核微生物
群落结构随短期水位恢复过程中的变异, 该研究在
一定程度上丰富了原核微生物群落结构对短期水位
响应的认识。李捷等(2021)尝试采用β多样性揭示植
物群落随小型啮齿草食动物干扰梯度变化的生态过
, 确立了冰草(Agropyron cristatum)、臭蒿
(Artemisia hedinii)和小花草玉梅(Anemone rivularis
var. flore-minore)对保护高原鼠兔干扰下高寒草甸
植物群落多样性的关键地位。针对人工草地, 姜鑫
和牛克昌(2021)开展青藏高原禾草混播对土壤微生
物多样性的影响, 认为在野外条件下高寒草地禾草
混播并不增加土壤微生物多样性。而刘攀等(2021)
筛选出适应高寒生境的草种, 认为土壤营养是维持
高寒人工草地生产力和稳定性的根本。此外, 本专
辑还收录了景观格局演变(薛鹏飞等, 2021)和基于
物候相机归一化植被指数(NDVI)估算高寒草地植物
地上生物量的季节动态(陈哲等, 2021)的研究文章,
旨在展示青藏高原高寒草地格局和过程研究的新的
方法和技术手段。
致谢 感谢中国科学院青藏高原研究所高原植被地
4 植物生态学报 Chinese Journal of Plant Ecology 2021, 45 (5): 00-00
www.plant-ecology.com
理与可持续管理研究组的王毅、叶冲冲、贺文、米
琦、李邵宇、张锦涛、刘天源、李若玮、李洋、何
豫川、兰翔宇和孙乐等的长期科考实践和讨论,
对本文的形成至关重要。
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