
青海高原国土空间生态保护修复工程气候变化压力分析
Analysis of climate change pressures on ecological protection and restoration projects of territorial space in Qinghai Plateau
气候变化是青海高原国土空间生态保护修复工作面临的主要压力之一,然而目前鲜有对该区域生态修复工程气候变化压力的量化分析。聚焦这一问题,基于多源数据,明确1960年以来青海高原的气候变化过程,分析土地覆被类型变化的气候驱动作用,并量化未来气候变化压力。研究发现:青海高原自1960年以来经历了显著的“暖湿化”过程,并呈西部升温快于东部、冬季升温快于夏季的特点。受气候变化的影响,青海高原草地和灌木分布在1980—2020年间呈现普遍扩张趋势,西北局部呈现收缩趋势。气候预测显示,青海高原将面临持续的气候变暖压力,尤其是南部地区。研究结果可为青海高原国土空间生态保护修复工程中相关气候缓解和适应措施的制定提供数据与理论支撑。
Climate change is one of the main pressures that the ecological protection and restoration in Qinghai Plateau continues to face, yet there is currently a lack of quantitative analysis of the climate change pressure on ecological restoration projects across this region. Focusing on this issue, this study clarified the climate change process across Qinghai Plateau since 1960, analyzed the driving effects of climate change on the changes in land cover, and quantified the projected future climate change pressures that Qinghai would face during the 21st century, based on multi-source data. We found that Qinghai Plateau has experienced significant warming-wetting trends since 1960, with the change characterized by faster warming in the west than in the east and faster in winter than in summer. Affected by climate changes, the distribution of grass-shrubs in the study area generally expanded from 1980 to 2020, while degraded in the northwest. Climate predictions indicate that Qinghai Plateau is likely to face profound pressures from continued warming trends across the 21st century, especially for the south. Our findings could serve as data and theoretical support for the formulation of relevant climate mitigation and adaptation measures in the ecological protection and restoration projects of territorial space in the plateau.
青海高原 / 生态保护修复 / 气候变化 / 生态保护修复分区 / 土地覆被变化 {{custom_keyword}} /
ecological protection and restoration / Qinghai Plateau / climate change / ecological protection and restoration zoning / land-cover change {{custom_keyword}} /
表1 不同预测情境下涵盖的大气环流模型Table 1 Global circulation models of climate projections under three Shared Socio-economic Pathways |
序号 | 大气环流模型(GCM) | SSP 1-26 | SSP 2-45 | SSP 5-85 |
---|---|---|---|---|
1 | ACCESS-CM2 | ● | ● | ● |
2 | ACCESS-ESM1-5 | ● | ● | ● |
3 | BCC-CSM2-MR | ● | ● | ● |
4 | CanESM5 | ● | ● | ● |
5 | CanESM5-CanOE | ● | ● | ● |
6 | CMCC-ESM2 | ● | ● | ● |
7 | CNRM-CM6-1 | ● | ● | ● |
8 | CNRM-CM6-1-HR | ● | ● | ● |
9 | CNRM-ESM2-1 | ● | ● | ● |
10 | EC-Earth3-Veg | ● | ● | ● |
11 | EC-Earth3-Veg-LR | ● | ● | ● |
12 | FIO-ESM-2-0 | ● | ● | ● |
13 | GFDL-ESM4 | ● | ○ | ○ |
14 | GISS-E2-1-G | ● | ● | ● |
15 | GISS-E2-1-H | ● | ● | ● |
16 | HadGEM3-GC31-LL | ● | ● | ● |
17 | INM-CM4-8 | ● | ● | ● |
18 | INM-CM5-0 | ● | ● | ● |
19 | IPSL-CM6A-LR | ● | ● | ● |
20 | MIROC-ES2L | ● | ● | ● |
21 | MIROC6 | ● | ● | ● |
22 | MPI-ESM1-2-HR | ● | ● | ● |
23 | MPI-ESM1-2-LR | ● | ● | ● |
24 | MRI-ESM2-0 | ● | ● | ● |
25 | UKESM1-0-LL | ● | ● | ● |
注:●表示对应模型有数据,○表示对应模型无数据。 |
图5 惠特克生物群系划分示意及青海高原1970—2000年气候空间基线和未来变化状况Fig. 5 The Whittaker's biome-types distribution and the near current (1970-2000) climate space occupied by Qinghai Plateau |
[1] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[2] |
傅伯杰, 欧阳志云, 施鹏, 等. 青藏高原生态安全屏障状况与保护对策. 中国科学院院刊, 2021, 36(11): 1298-1306.
[
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[3] |
王军, 应凌霄, 钟莉娜. 新时代国土整治与生态修复转型思考. 自然资源学报, 2020, 35(1): 26-36.
针对全球变化影响下的国土空间和生态系统,生态文明建设和国土空间规划是中国在新时代的积极响应,国土整治与生态修复的转型和提升成为必然要求。在介绍国土整治与生态修复概念内涵的基础上,指出中国国土空间生态环境问题的复杂性和生态文明建设的新理念要求决定了国土整治与生态修复的转型。从工作理念、理论基础、技术体系和制度建设等方面,分析了当前国土整治与生态修复工作中存在的不足,主要包括整体综合理念滞后、理论基础体系欠缺、技术支撑相对薄弱、体制机制不尽完善等方面。针对这些不足,提出了新时代国土整治与生态修复转型的路径和策略,主要策略包括强化系统思维、提升理论体系、加强技术支撑、完善机制建设等内容,以期为国土整治与生态修复推进美丽中国建设提供科学依据。
[
As the national land space and ecosystems are affected by global change nowadays, ecological civilization construction and land spatial planning must be the positive responses of China in the new era. Great achievements have been made in the restorations of ecological space and ecosystems through projects for land consolidation and ecological restoration. However, the degradation of some regional ecosystems still exists, and the interference of unreasonable traditional human activities has not been completely eliminated in China. Meanwhile, China faces a large number of challenges in the economic and social developments of the new era. The transformation and improvement of land consolidation and ecological restoration therefore become the inevitable requirement. Through introducing the concepts, connotations of land consolidation, ecological restoration and relationships between them in the new era, this paper suggested that the transformation should be determined by the variations and complexities of regional ecological and environmental issues, the new requirements of ecological civilization construction and land spatial planning. We also indicated the four shortcomings of land consolidation and ecological restoration at present, including working perception, theoretical basis, technological system, and institutional construction. Specifically in recent practices, the integrated and comprehensive concepts are lagging behind, the key theoretical systems are deficient, the technological supports are instable, and the related institutions are insufficient. Therefore, we proposed the strategies for the corresponding transformation, which mainly included: (1) intensifying the systematic thinking and concept to promote the implementation of land consolidation and ecological restoration on a regional basis; (2) upgrading the theoretical system to stimulate the new motivation for land consolidation and ecological restoration; (3) enhancing the technical support to improve the effectiveness of land consolidation and ecological restoration works; (4) improving the institution construction to reinforce the support foundation for land consolidation and ecological restoration implementations. {{custom_citation.content}}
{{custom_citation.annotation}}
|
[4] |
IPCC. Global Warming of 1.5 ℃: IPCC Special Report on Impacts of Global Warming of 1.5 ℃ above Pre-industrial Levels in Context of Strengthening Response to Climate Change, Sustainable Development, and Efforts to Eradicate Poverty. Cambridge: Cambridge University Press, 2018.
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[5] |
王宁练, 姚檀栋, 徐柏青, 等. 全球变暖背景下青藏高原及周边地区冰川变化的时空格局与趋势及影响. 中国科学院院刊, 2019, 34(11): 1220-1232.
[
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[6] |
朱立平, 张国庆, 杨瑞敏, 等. 青藏高原最近40年湖泊变化的主要表现与发展趋势. 中国科学院院刊, 2019, 34(11): 1254-1263.
[
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[7] |
张慧, 朱文泉, 史培军, 等. 青藏高原各主要植被类型特征及环境差异. 生态学报, 2024, 44(7): 2955-2970.
[
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[8] |
王军, 张骁, 高岩. 青藏高原植被动态与环境因子相互关系的研究现状与展望. 地学前缘, 2021, 28(4): 70-82.
青藏高原是中国乃至全球对气候变化最敏感的地区之一,是全球平均海拔最高的地理单元,对周边地区起到重要的生态安全屏障作用。近年来,当地植被受到气候变化和人类活动的双重压力。本文基于文献检索分析青藏高原的植被生理、生态特征对气候变化和人为干扰的响应,并利用荟萃分析定量综述植被覆盖度变化对土壤理化性质的影响。在此基础上分析青藏高原植被与环境因子相互关系的研究尺度与方法。结果表明:(1)气温、降水、辐射等自然因素和放牧、农耕、筑路等人为活动均对青藏高原植被的碳交换、水分利用效率、元素含量与分布格局、物候、多样性等指标产生显著影响,植被的变化也同时影响着土壤的水热交换、水文过程和理化性质等;(2)在植被退化过程中,由高覆盖度向中覆盖度转变时对土壤理化性质产生的不利影响强于由中覆盖度转为低覆盖度时,高覆盖度地区的植被保护需要引起更多关注;(3)现有研究更多关注单一要素、单一尺度,未来应关注多要素间的相互耦合,通过合作与共享获取数据,开展多尺度对比和尺度效应研究,系统梳理和分析植被与环境因子的相互关系可为制定科学合理的生态修复策略提供科学依据。
[
The Qinghai-Tibet plateau is one of the regions most sensitive to climate change both in China and in the world at large. In recent years, local vegetation has been under the dual pressure from climate change and human activities. Its physiological and ecological characteristics, in response to climate change and human interference, were analyzed in this paper based on literature research, and the impact of change in vegetation coverage on soil physical and chemical properties were quantitatively summerized based on meta-analysis. On this basis, this paper reviewed the research scales and methods in studying the relationship between vegetation and environmental factors on the Qinghai-Tibet plateau and summerized the results as the follows: 1) Natural factors such as temperature, precipitation and radiation, and human activities such as grazing, farming and road construction, significantly affected the carbon exchange, water use efficiency, elemental content and distribution pattern, phenological period and diversity of vegetation. The change of vegetation also affected the water heat exchange, hydrological process and physical and chemical properties of soil. 2) In the process of vegetation degradation, the changes in vegetation coverage from high to medium had a stronger negative effect on the physical and chemical properties of soil than changes from medium to low; therefore, more attention should be paid to vegetation protection in the high coverage area. 3) Previous researches mainly focused on the impact of a single factor and a single scale. In future, more attention should be paid to multi-factor coupling by considering the intra- and out-of-domain effects on the ecosystem. Besides, multi-scale comparison and scale-effect research should be conducted to explore the ecological restoration strategies and climate change coping mechanisms at different scales based on data compiled through cooperation and data sharing. To implement further research, it is also necessary to integrate multi-source, multi-point, long-term series monitoring data to establish an observational network covering the whole Qinghai-Tibet plateau. In addition, data sharing should be strengthened to save research resources while reducing damage caused by unnecessary repeated sampling to the fragile plateau ecosystem. The systematic review of the relationships between vegetation and environmental factors could be applied to the planning, design and monitoring of ecological protection and restoration projects, so as to develop the ecological protection and restoration technology and management system suitable for the Qinghai-Tibet plateau region, and also provide support for policy-making in this region. {{custom_citation.content}}
{{custom_citation.annotation}}
|
[9] |
刘飞, 刘峰贵, 周强, 等. 青藏高原生态风险及区域分异. 自然资源学报, 2021, 36(12): 3232-3246.
全球变化背景下,青藏高原生态系统受到自然、人为双重影响和威胁,生态风险日益加剧。针对生态风险源、脆弱性以及风险管理能力选取30个评估指标,利用生态风险评估优化模型,综合评估了青藏高原的生态风险,并得出如下结论:青藏高原生态风险总体处于较低水平,以低和极低生态风险为主,共占研究区面积的55.84%;极高风险主要分布在北部高山和极高山地区,中等风险主要分布在高原北部以及高原的西部和西南部地区,中、高生态风险在空间分布上形成一个“C”字形结构;青藏高原生态风险整体受自然主导因子控制,人为对生态环境的影响不容忽视,协调和降低青藏高原人类活动区域人类对生态环境的影响,是今后规避生态风险的重要途径。
[
Under the background of global change, the ecosystem of the Qinghai-Tibet Plateau has been affected and threatened by both nature and human activities, and the ecological risks are intensifying. The Qinghai-Tibet Plateau is a relatively independent geographic unit with a high average altitude and complex and diverse landforms. Its fragile alpine ecosystem is extremely sensitive to global climate change. In recent years, the population of the plateau has increased and the process of urbanization has accelerated, the scale and intensity of human activities have increased significantly, and ecological risks have increased. At present, the research results of ecological risk assessment are mainly found in local areas of the Qinghai-Tibet Plateau. This article, aiming at understanding the source of ecological risks, analyzes the spatial distribution of risks and their causes. The ecological risk assessment of the entire plateau is expected to provide references for the identification, management and early warning of regional ecological risks. We establish an ecological risk assessment index system for the study area, which includes 13 ecological risk source indicators, 10 ecological vulnerability indicators, and 7 ecological risk management capability indicators. Then we select the official remote sensing product data with a high spatial resolution, according to the characteristics of the data which are divided into numerical and non-numerical data. Using ArcGIS 10.2 to normalize the numerical data, according to the contribution rate to ecological risk, the non-numerical data are graded, and the ecological risk evaluation optimization model is used to comprehensively evaluate the ecological risk of the plateau. The results showed that: overall ecological risk of the study area is relatively low, with low and very low ecological risk areas accounting for 55.84%, extremely high risk areas being only 7.19%, high risk areas 11.95%, and medium ecological risk areas 25.02%, and the extremely low and low ecological risk areas account for more than half of the plateau area; medium ecological risk areas are mainly distributed in areas with high intensity of human activities. The impact of human activities on the eco-environment of the Qinghai-Tibet Plateau cannot be ignored; the extremely high-risk areas and medium-risk areas form a "C"-shaped pattern; the low-risk areas in the hinterland of the plateau have higher altitudes, severe cold climates, and fragile eco-environments, but the strengthening of ecological management measures has greatly reduced the ecological risk in the study area. The overall ecological risk of the Qinghai-Tibet Plateau is mainly controlled by natural factors, and the impact of human activities on the eco-environment cannot be ignored. The establishment of national nature reserves or national parks to protect the ecological environment can greatly reduce its ecological risks. It is necessary to pay special attention to areas with high intensity of human activities on the plateau, where their ecological risks have reached a medium intensity. Creating a new pattern of harmonious coexistence between humans and nature, and avoiding excessive human intervention in the eco-environment on the Qinghai-Tibet Plateau is an important way to reduce ecological risks in the future. {{custom_citation.content}}
{{custom_citation.annotation}}
|
[10] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[11] |
李林, 李晓东, 校瑞香, 等. 青藏高原东北部气候变化的异质性及其成因. 自然资源学报 2019, 34(7): 1496-1505.
利用1961-2016年西宁等青藏高原东北部13个气象台站气温、降水等气象资料以及国家气候中心发布的南海季风指数、西伯利亚高压指数等大气环流特征量数据,分析近56年来气候变化与高原主体的差异性及其可能的气候成因。研究表明:近56年来青藏高原东北部气候变暖趋势十分显著,年平均气温气候倾向率高达0.39 ℃/10 a,呈现出三次明显的阶梯性增高态势,并于1994年前后发生了由冷到暖的突变,同时具有明显的空间差异性;年降水量及四季降水量均没有明显变化趋势,虽然经历了2002年左右由少到多的变化,但并未出现明显突变,年降水量具有3年、5年的准周期,而年降水日数微弱减少,降水强度呈增加趋势;该区域气候变化的年际波动主要受到东亚季风、高原季风和南海季风的年际振荡及其相互作用的影响,而西风环流的作用并不明显,植被覆盖的恢复既是对2002年以来降水量增加的具体反应,同时也对于气候变暖趋势起到了一定的缓和作用。
[
The northeastern part of Qinghai-Tibet Plateau is situated in the transitional zone of the Qinghai-Tibet Plateau and Loess Plateau. Known as Qinghai's Hehuang areas, it is the valleys of Yellow River and Huangshui River. And it is the birthplace of civilization and cradle of economic and social development of the Qinghai-Tibet Plateau, especially Qinghai province. It is also one of the areas of earliest human activities in the Yellow River Basin. Because it is located in the intersection of China's two high plateaus, its climate and its changes have a certain heterogeneity. The northeastern part of Qinghai-Tibet Plateau has some characteristics of the East Asian monsoon climate, which is different from complete plateau continental climate. Therefore, due to complexity of its climate change and significance of its impact on economy and society, the issue of climate change in the region has received wide attention from academic community. Based on analysis of climate change in the northeastern part of Qinghai-Tibet Plateau from 1961 to 2016 and its heterogeneity in climate change over the Qinghai-Tibet Plateau, this paper discusses the causes of climate change from evolution of atmospheric circulation and changes in vegetation cover. The meteorological data such as temperature, precipitation and other meteorological data of 13 meteorological stations in the northeastern Qinghai-Tibet Plateau from 1961 to 2016, the data of atmospheric circulation characteristics such as the South China Sea summer monsoon index and Siberian High Index released by the National Climate Center were analyzed in this paper. And, the heterogeneity between climate change and plateau main body and their possible climate genesis were also analyzed in the past 56 years. The results are shown as follows: (1) Climate warming trend in the northeastern part of Qinghai-Tibet Plateau is very significant in the past 56 years. The climatic tendency rate of annual average temperature is as high as 0.39 °C/10 a, showing three obvious stepwise increases and it has mutations from cold to warm around 1994 with significant spatial variability. (2) There is no obvious change in annual and seasonal precipitation. Although it has experienced less to more changes around 2002, there is no significant mutation. The annual precipitation has a quasi-periodic variations of 3 years and 5 years, while the number of annual precipitation days is slightly reduced and precipitation intensity is increasing. (3) The interannual variability of climate change in this region is mainly affected by interannual oscillations of East Asian monsoon, plateau monsoon and South China Sea monsoon and their interactions, while effect of westerly circulation is not obvious. The restoration of vegetation cover has not only responded to precipitation increase since 2002 but also played a certain role of mitigative effect in climate warming trend.
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[12] |
陈舒婷, 郭兵, 杨飞, 等. 2000—2015年青藏高原植被NPP时空变化格局及其对气候变化的响应. 自然资源学报, 2020, 35(10): 2511-2527.
全球变化背景下,青藏高原作为我国乃至全球气候变化的“天然实验室”,植被生态系统发生了深刻变化。引入重心模型等方法分析和探讨2000—2015年青藏高原植被NPP时空变化格局及其驱动机理,并定量区分NPP变化过程中气候变化和人类活动的相对作用。研究发现:(1)2000—2015年,青藏高原植被NPP年均值总体上呈现从东南向西北递减的趋势。在年际变化方面,近16年植被NPP呈现波动上升趋势,其中在2005年出现上升陡坡,并在2005—2015年表现为高位波动的态势。(2)青藏高原植被NPP增加区(变化率>10%)主要集中于三江源地区、横断山区北部、雅鲁藏布江中下游以及那曲地区的中东部,而植被NPP减小区(变化率<-10%)则主要分布于雅鲁藏布江上游和阿里高原。(3)近16年青藏高原植被NPP重心总体向西南方向移动,表明西南部植被NPP在增量和增速上大于东北部。(4)青藏高原植被NPP与气候因子相关性的地区差异显著,其中植被NPP与降水显著相关的区域主要位于青藏高原中部、青藏高原东南部及雅鲁藏布江流域中下游,而植被NPP与气温显著相关的区域主要位于藏南地区、横断山区北部、青藏高原中部和北部。(5)气候变化和人类活动在青藏高原植被NPP变化过程中的相对作用存在显著的时空差异性,在空间上呈现“四线—五区”的格局。研究成果能够为揭示青藏高原区域生态系统对全球变化的响应机制提供理论和方法支撑。
[
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[13] |
丁明军, 张镱锂, 刘林山, 等. 1982—2009年青藏高原草地覆盖度时空变化特征. 自然资源学报, 2010, 25(12): 2114-2122.
利用GIMMS和SPOT VGT两种归一化植被指数(NDVI)数据对青藏高原地区1982—2009年期间草地覆盖的时空变化进行研究,结果如下:①青藏高原草地植被覆盖的年际变化存在着显著的空间差异。趋于升高的区域主要分布在西藏的北部和新疆的南部;趋于下降的地区主要分布在青海的柴达木盆地、祁连山、共和盆地、江河源地区及川西地区。②青藏高原草地覆盖度年际变化趋势分析表明,在90%的显著性检验水平上,降低和增加面积的比率为0.31,草地植被覆盖水平总体趋于升高态势。③以10 a为步长的分析表明:草地盖度呈现持续增加的区域主要分布在西藏北部;阿里地区草地盖度表现为先减少后增加;雅鲁藏布江流域草地盖度呈现先增加而后减少;而持续减少的区域主要分布在青海省以及川西地区,其中青海省分布最广;统计结果显示,高原大部分地区草地盖度具有升高的态势。
[
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[14] |
杨亮, 刘丽男, 孙少波. 1982—2015年青藏高原植被变化的主导环境因子. 生态学报, 2023, 43(2): 744-755.
[
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[15] |
刘旻霞, 焦骄, 潘竟虎, 等. 青海省植被净初级生产力(NPP)时空格局变化及其驱动因素. 生态学报, 2020, 40(15): 5306-5317.
[
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[16] |
贾艳青, 张勃. 1960—2016年中国北方地区极端干湿事件演变特征. 自然资源学报, 2019, 34(7): 1543-1554.
基于中国北方地区424个气象站点1960-2016年的日气象数据础,应用FAO Penman-Monteith模型计算潜在蒸散(ET<sub>0</sub>),基于降水量和潜在蒸散计算湿润指数,对湿润指数进行标准化后统计极端干湿事件频率,分析极端干湿事件频率的空间变化趋势、多时间尺度演变特征以及ENSO事件对极端干湿事件变化趋势的影响。结果表明:北方极端干旱和极端湿润事件频率分别呈显著下降和显著上升趋势,年际倾向率分别为-0.10次/10年和0.13次/10年。空间上,极端干旱频率整体呈减少趋势,包括青藏高原、西北和东北地区。西北极端干旱频率减少速率较大,青藏高原中部、新疆北部和东北北部部分站点极端湿润频率增加幅度较大。各年代中,华北极端干旱多发,东北和青藏高原极端湿润多发。季节上,分区极端干旱发生概率均大于极端湿润发生概率,华北极端干旱发生概率最高,青藏高原极端湿润发生概率最高。ENSO与湿润指数存在滞后性的关系。El Niño翌年,气候偏湿润的年份较多;La Nina翌年,气候偏干旱的年份较多。SSTA与翌年湿润指数在年际和夏季两个时间尺度上存在显著的正相关关系。
[
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[17] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[18] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[19] |
Larch, a widely distributed tree in boreal Eurasia, is experiencing rapid warming across much of its distribution. A comprehensive assessment of growth on warming is needed to comprehend the potential impact of climate change. Most studies, relying on rigid calendar-based temperature series, have detected monotonic responses at the margins of boreal Eurasia, but not across the region. Here, we developed a method for constructing temporally flexible and physiologically relevant temperature series to reassess growth-temperature relations of larch across boreal Eurasia. Our method appears more effective in assessing the impact of warming on growth than previous methods. Our approach indicates widespread and spatially heterogeneous growth-temperature responses that are driven by local climate. Models quantifying these results project that the negative responses of growth to temperature will spread northward and upward throughout this century. If true, the risks of warming to boreal Eurasia could be more widespread than conveyed from previous works.© 2023. The Author(s).
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[20] |
Forests around the world are subject to risk of high rates of tree growth decline and increased tree mortality from combinations of climate warming and drought, notably in semi-arid settings. Here, we assess how climate warming has affected tree growth in one of the world's most extensive zones of semi-arid forests, in Inner Asia, a region where lack of data limits our understanding of how climate change may impact forests. We show that pervasive tree growth declines since 1994 in Inner Asia have been confined to semi-arid forests, where growing season water stress has been rising due to warming-induced increases in atmospheric moisture demand. A causal link between increasing drought and declining growth at semi-arid sites is corroborated by correlation analyses comparing annual climate data to records of tree-ring widths. These ring-width records tend to be substantially more sensitive to drought variability at semi-arid sites than at semi-humid sites. Fire occurrence and insect/pathogen attacks have increased in tandem with the most recent (2007-2009) documented episode of tree mortality. If warming in Inner Asia continues, further increases in forest stress and tree mortality could be expected, potentially driving the eventual regional loss of current semi-arid forests. © 2013 John Wiley & Sons Ltd.
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[21] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[22] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[23] |
CRU TS (Climatic Research Unit gridded Time Series) is a widely used climate dataset on a 0.5° latitude by 0.5° longitude grid over all land domains of the world except Antarctica. It is derived by the interpolation of monthly climate anomalies from extensive networks of weather station observations. Here we describe the construction of a major new version, CRU TS v4. It is updated to span 1901-2018 by the inclusion of additional station observations, and it will be updated annually. The interpolation process has been changed to use angular-distance weighting (ADW), and the production of secondary variables has been revised to better suit this approach. This implementation of ADW provides improved traceability between each gridded value and the input observations, and allows more informative diagnostics that dataset users can utilise to assess how dataset quality might vary geographically.
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[24] |
张慧, 赵涔良, 朱文泉. 基于多源数据产品集成分类制作的青藏高原现状植被图. 北京师范大学学报: 自然科学版, 2021, 57(6): 816-824.
[
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[25] |
周继华, 郑元润, 宋长青, 等. 青藏高原近似复原植被图. 国家青藏高原数据中心, 2022, https://data.tpdc.ac.cn/en/data/3a49fac7-bf9d-4b69-a855-bd2380ebaa0b.
[
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[26] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[27] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[28] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[29] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[30] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[31] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[32] |
Mountain treelines are thought to be sensitive to climate change. However, how climate impacts mountain treelines is not yet fully understood as treelines may also be affected by other human activities. Here, we focus on "closed-loop" mountain treelines (CLMT) that completely encircle a mountain and are less likely to have been influenced by human land-use change. We detect a total length of ~916,425 km of CLMT across 243 mountain ranges globally and reveal a bimodal latitudinal distribution of treeline elevations with higher treeline elevations occurring at greater distances from the coast. Spatially, we find that temperature is the main climatic driver of treeline elevation in boreal and tropical regions, whereas precipitation drives CLMT position in temperate zones. Temporally, we show that 70% of CLMT have moved upward, with a mean shift rate of 1.2 m/year over the first decade of the 21st century. CLMT are shifting fastest in the tropics (mean of 3.1 m/year), but with greater variability. Our work provides a new mountain treeline database that isolates climate impacts from other anthropogenic pressures, and has important implications for biodiversity, natural resources, and ecosystem adaptation in a changing climate.© 2023 John Wiley & Sons Ltd.
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[33] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[34] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[35] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
[36] |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
{{custom_ref.label}} |
{{custom_citation.content}}
{{custom_citation.annotation}}
|
/
〈 |
|
〉 |