scholarly journals Mapping Plant Functional Types over Broad Mountainous Regions: A Hierarchical Soft Time-Space Classification Applied to the Tibetan Plateau

2014 ◽  
Vol 6 (4) ◽  
pp. 3511-3532 ◽  
Author(s):  
Danlu Cai ◽  
Yanning Guan ◽  
Shan Guo ◽  
Chunyan Zhang ◽  
Klaus Fraedrich
Keyword(s):  
Tibetan Plateau ◽  
Plant Functional Types ◽  
The Tibetan Plateau ◽  
Mountainous Regions ◽  
Functional Types ◽  
Time Space

scholarly journals Elevational Movement of Vegetation Greenness on the Tibetan Plateau: Evidence from the Landsat Satellite Observations during the Last Three Decades

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 161
Author(s):  
Liheng Lu ◽  
Xiaoqian Shen ◽  
Ruyin Cao
Keyword(s):  
Tibetan Plateau ◽  
Spatial Resolution ◽  
Climate Warming ◽  
Vertical Movement ◽  
The Tibetan Plateau ◽  
Upward Movement ◽  
Vegetation Growth ◽  
Vegetation Greenness ◽  
Mountainous Regions ◽  
Vegetation Activities

The Tibetan Plateau, the highest plateau in the world, has experienced strong climate warming during the last few decades. The greater increase of temperature at higher elevations may have strong impacts on the vertical movement of vegetation activities on the plateau. Although satellite-based observations have explored this issue, these observations were normally provided by the coarse satellite data with a spatial resolution of more than hundreds of meters (e.g., GIMMS and MODIS), which could lead to serious mixed-pixel effects in the analyses. In this study, we employed the medium-spatial-resolution Landsat NDVI data (30 m) during 1990–2019 and investigated the relationship between temperature and the elevation-dependent vegetation changes in six mountainous regions on the Tibetan Plateau. Particularly, we focused on the elevational movement of the vegetation greenness isoline to clarify whether the vegetation greenness isoline moves upward during the past three decades because of climate warming. Results show that vegetation greening occurred in all six mountainous regions during the last three decades. Increasing temperatures caused the upward movement of greenness isoline at the middle and high elevations (>4000 m) but led to the downward movement at lower elevations for the six mountainous regions except for Nyainqentanglha. Furthermore, the temperature sensitivity of greenness isoline movement changes from the positive value to negative value by decreasing elevations, suggesting that vegetation growth on the plateau is strongly regulated by other factors such as water availability. As a result, the greenness isoline showed upward movement with the increase of temperature for about 59% pixels. Moreover, the greenness isoline movement increased with the slope angles over the six mountainous regions, suggesting the influence of terrain effects on the vegetation activities. Our analyses improve understandings of the diverse response of elevation-dependent vegetation activities on the Tibetan Plateau.

scholarly journals Vegetation Dynamics on the Tibetan Plateau (1982–2006): An Attribution by Ecohydrological Diagnostics

2015 ◽  
Vol 28 (11) ◽  
pp. 4576-4584 ◽  
Author(s):  
Danlu Cai ◽  
Klaus Fraedrich ◽  
Frank Sielmann ◽  
Ling Zhang ◽  
Xiuhua Zhu ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Tibetan Plateau ◽  
State Space ◽  
Weather Data ◽  
Target Area ◽  
The Tibetan Plateau ◽  
Net Radiation ◽  
Vegetation Greenness ◽  
Mountainous Regions ◽  
Second Period

Abstract Vegetation greenness distributions [based on remote sensing normalized difference vegetation index (NDVI)] and their change are analyzed as functional vegetation–climate relations in a two-dimensional ecohydrological state space spanned by surface flux ratios of energy excess (U; loss by sensible heat H over supply by net radiation N) versus water excess (W; loss by discharge Ro over gain by precipitation P). An ecohydrological ansatz attributes state change trajectories in (U, W) space to external (or climate) and internal (or anthropogenic) causes jointly with vegetation greenness interpreted as an active tracer. Selecting the Tibetan Plateau with its complex topographic, climate, and vegetation conditions as target area, ERA-Interim weather data link geographic and (U, W) state space, into which local remote sensing Global Inventory Modeling and Mapping Studies (GIMMS) data (NDVI) are embedded; a first and second period (1982–93 and 1994–2006) are chosen for change attribution analysis. The study revealed the following results: 1) State space statistics are characterized by a bimodal distribution with two distinct geobotanic regimes (semidesert and steppe) of low and moderate vegetation greenness separated by gaps at aridity D ~ 2 (net radiation over precipitation) and greenness NDVI ~ 0.3. 2) Changes between the first and second period are attributed to external (about 70%) and internal (30%) processes. 3) Attribution conditioned joint distributions of NDVI (and its change) show 38.2% decreasing (61.8% increasing) area cover with low (moderate) greenness while high greenness areas are slightly reduced. 4) Water surplus regions benefit most from climate change (showing vegetation greenness growth) while the energy surplus change is ambiguous, because ecohydrological diagnostics attributes high mountainous regions (such as the Himalayas) as internal without considering the heat storage deficit due to increasing vegetation.

scholarly journals Sub-recent Ostracoda from Qilian Mountains, NW China

2003 ◽  
Vol 22 (2) ◽  
pp. 137-138 ◽  
Author(s):  
Steffen Mischke ◽  
Ulrike Herzschuh ◽  
Harald Kürschner ◽  
Fahu Chen ◽  
Fei Meng ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Sea Level ◽  
Qilian Mountains ◽  
The Tibetan Plateau ◽  
Nw China ◽  
Mountainous Regions ◽  
History Of ◽  
Climatic History ◽  
The Qilian Mountains ◽  
First Time

Abstract. To our knowledge, the Qilian Mountains in NW China have been investigated with respect to Recent or sub-Recent ostracods for the first time. The Qilian Mountains (95–103°E/37–40°N) extend along the northeastern margin of the Tibetan Plateau reaching a maximum altitude of 5826 m above sea-level (m asl).In September 2001, surface mud from the bottom of various water bodies including brooks, rivers and small shallow meadow and oxbow pools were sampled at an altitude ranging from 2900 m to 3570 m asl. In addition, surface mud samples and short cores were obtained from the small (c. 1 km2) and shallow (<0.4 m) freshwater Lake Luanhaizi situated at about 3200 m asl.Ostracod valves were usually abundant in all of the 32 samples and comprised the taxa listed in Table 1, some of which are illustrated in Plate 1.The recorded taxa are mainly distributed in the holarctic realm but Fabaeformiscandona danielopoli and Ilyocypris echinata appear to be restricted to the cold mountainous regions in China (Huang, 1985; Wang &amp; Zhu, 1991; Sun et al., 1995; Yin &amp; Martens, 1997).Following the first survey, a 14 m long core was drilled in Lake Luanhaizi in January 2002 which is currently under multidisciplinary investigation to reconstruct the Holocene vegetation and climatic history of the Qilian Mountains.

scholarly journals Simulated annual changes in plant functional types and their responses to climate change on the northern Tibetan Plateau

2016 ◽  
Vol 13 (12) ◽  
pp. 3533-3548 ◽  
Author(s):  
Lan Cuo ◽  
Yongxin Zhang ◽  
Shilong Piao ◽  
Yanhong Gao
Keyword(s):  
Climate Change ◽  
Water Resources ◽  
Tibetan Plateau ◽  
Soil Temperature ◽  
Root Zone ◽  
Plant Functional Types ◽  
Atmospheric Conditions ◽  
Dynamic Global Vegetation Model ◽  
Northern Tibetan Plateau ◽  
Functional Types

Abstract. Changes in plant functional types (PFTs) have important implications for both climate and water resources. Still, little is known about whether and how PFTs have changed over the past decades on the northern Tibetan Plateau (NTP) where several of the top largest rivers in the world are originated. Also, the relative importance of atmospheric conditions vs. soil physical conditions in affecting PFTs is unknown on the NTP. In this study, we used the improved Lund–Potsdam–Jena Dynamic Global Vegetation Model to investigate PFT changes through examining the changes in foliar projective coverages (FPCs) during 1957–2009 and their responses to changes in root zone soil temperature, soil moisture, air temperature, precipitation and CO2 concentrations. The results show spatially heterogeneous changes in FPCs across the NTP during 1957–2009, with 34 % (13 %) of the region showing increasing (decreasing) trends. Dominant drivers responsible for the observed FPC changes vary with regions and vegetation types, but overall, precipitation is the major factor in determining FPC changes on the NTP with positive impacts. Soil temperature increase exhibits small but negative impacts on FPCs. Different responses of individual FPCs to regionally varying climate change result in spatially heterogeneous patterns of vegetation changes on the NTP. The implication of the study is that fresh water resources in one of the world's largest and most important headwater basins and the onset and intensity of Asian monsoon circulations could be affected because of the changes in FPCs on the NTP.

scholarly journals Reconstruction of the Catastrophic Outburst Floods of the Diexi Ancient Landslide-Dammed Lake in the Upper Minjiang River, Eastern Tibetan Plateau

2021 ◽  
Author(s):  
Junxue Ma ◽  
Jian Chen ◽  
Zhijiu Cui ◽  
Wendy Zhou ◽  
Ruichen Chen ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Landslide Dam ◽  
Peak Discharge ◽  
The Tibetan Plateau ◽  
Lake Area ◽  
Ancient Landslide ◽  
Mountainous Regions ◽  
Minjiang River ◽  
Outburst Floods ◽  
Dammed Lake

Abstract Landslide-dammed lake outburst floods (LLOFs) may pose serious safety threats to nearby residents and their livelihoods, as well as cause major damages to the downstream areas in mountainous regions. This study presents the Diexi ancient landslide-dammed lake (DALL) in the Upper Minjiang River at the eastern margins of the Tibetan Plateau, which was known to an estimated previous maximal lake area of 1.1 × 107 m2 and an impounded volume of 2.9 × 109 m3. Then, at approximately 27 ka BP, the ancient landslide dam failed and catastrophic LLOFs occurred. It was determined that the peak discharge of the Diexi ancient LLOFs could be reconstructed using regression, parametric, and boulder competence approaches. The reconstructed maximum peak discharge might be 72,232.66 m3/s, with an average velocity of 17.23 m/s, indicating that the Diexi ancient LLOFs were the most gigantic outburst floods to occur in the Upper Minjiang River Valley since the Late Pleistocene Period. The differences in the widths and slopes within the former and the later reaches of the dam indicated that the geomorphic influences on the river channel resulting from the DALL and its LLOFs have existed for tens of thousands of years. These findings were of major significance in deepening the understanding of the existence and disappearances of important river-knickpoints on a time scale of tens of thousands of years.

scholarly journals Annual changes in plant functional types and their responses to climate change on the Northern Tibetan Plateau

2016 ◽  
Author(s):  
Lan Cuo ◽  
Yongxin Zhang ◽  
Shilong Piao ◽  
Yanhong Gao
Keyword(s):  
Climate Change ◽  
Water Resources ◽  
Tibetan Plateau ◽  
Soil Temperature ◽  
Root Zone ◽  
Plant Functional Types ◽  
Atmospheric Conditions ◽  
Dynamic Global Vegetation Model ◽  
Northern Tibetan Plateau ◽  
Functional Types

Abstract. Changes in plant functional types (PFTs) have important implications for both climate and water resources. Still, little is known about whether and how PFTs have changed over the past decades on the Northern Tibetan Plateau (NTP) where several of the top largest rivers in the world are originated. Also, the relative importance of atmospheric conditions versus soil physical conditions in affecting PFTs is unknown on the NTP. In this study, we used the improved Lund-Potsdam-Jena Dynamic Global Vegetation Model to investigate PFT changes through examining the changes in foliar projective coverages (FPCs) during 1957–2009 and their responses to changes in root zone soil temperature, soil moisture, air temperature, precipitation and CO2 concentrations. The results show spatially heterogeneous changes in FPCs across the NTP during 1957–2009, with 34 % (13 %) of the region showing increasing (decreasing) trends. Dominant drivers responsible for the observed FPC changes vary with regions and vegetation types, but overall, precipitation is the major factor in determining FPC changes on the NTP with positive impacts. Soil temperature increase exhibits small but negative impacts on FPCs. Different responses of individual FPCs to regionally varying climate change result in spatially heterogeneous patterns of vegetation changes on the NTP. The implication of the study is that fresh water resources in one of the world's largest and most important headwater basins and the onset and intensity of Asian monsoon circulations could be affected because of the changes in FPCs on the NTP.

scholarly journals Black carbon and mineral dust in snow cover on the Tibetan Plateau

2018 ◽  
Vol 12 (2) ◽  
pp. 413-431 ◽  
Author(s):  
Yulan Zhang ◽  
Shichang Kang ◽  
Michael Sprenger ◽  
Zhiyuan Cong ◽  
Tanguang Gao ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Organic Carbon ◽  
Snow Cover ◽  
Black Carbon ◽  
Mineral Dust ◽  
Back Trajectory ◽  
Climate Projections ◽  
The Tibetan Plateau ◽  
Air Masses ◽  
Mountainous Regions

Abstract. Snow cover plays a key role for sustaining ecology and society in mountainous regions. Light-absorbing particulates (including black carbon, organic carbon, and mineral dust) deposited on snow can reduce surface albedo and contribute to the near-worldwide melting of snow and ice. This study focused on understanding the role of black carbon and other water-insoluble light-absorbing particulates in the snow cover of the Tibetan Plateau (TP). The results found that the black carbon, organic carbon, and dust concentrations in snow cover generally ranged from 202 to 17 468 ng g−1, 491 to 13 880 ng g−1, and 22 to 846 µg g−1, respectively, with higher concentrations in the central to northern areas of the TP. Back trajectory analysis suggested that the northern TP was influenced mainly by air masses from Central Asia with some Eurasian influence, and air masses in the central and Himalayan region originated mainly from Central and South Asia. The relative biomass-burning-sourced black carbon contributions decreased from ∼ 50 % in the southern TP to ∼ 30 % in the northern TP. The relative contribution of black carbon and dust to snow albedo reduction reached approximately 37 and 15 %, respectively. The effect of black carbon and dust reduced the snow cover duration by 3.1 ± 0.1 to 4.4 ± 0.2 days. Meanwhile, the black carbon and dust had important implications for snowmelt water loss over the TP. The findings indicate that the impacts of black carbon and mineral dust need to be properly accounted for in future regional climate projections, particularly in the high-altitude cryosphere.

Author response for "Oligocene vegetation of Europe and western Asia-Diversity change and continental patterns reflected by plant functional types"

2020 ◽  
Author(s):  
Utescher, Torsten ◽  
Erdei, Boglarka ◽  
Francois, Louis ◽  
Henrot, Alexandra-Jane ◽  
Mosbrugger, Volker ◽  
...  
Keyword(s):  
Plant Functional Types ◽  
Author Response ◽  
Functional Types ◽  
Western Asia
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