Frost stress evolution and winter pea ideotype in the context of climate warming at a regional scale

Alpine sparsely vegetated areas (ASVAs) in mountains are sensitive to climate change and rarely studied. In this study, we focused on the response of ASVA distribution to climate change in the eastern Qilian Mountains (EQLM) from the 1990s to the 2010s. The ASVA distribution ranges in the EQLM during the past three decades were obtained from the Thematic Mapper remote sensing digital images by using the threshold of normalized difference vegetation index (NDVI) and artificial visual interpretation. Results indicated that the ASVA shrank gradually in the EQLM and lost its area by approximately 11.4% from the 1990s to the 2010s. The shrunken ASVA with markedly more area than the expanded one was mainly located at altitudes from 3700 m to 4300 m, which were comparatively lower than the average altitude of the ASVA distribution ranges. This condition led to the low ASVA boundaries in the EQLM moving upwards at a significant velocity of 22 m/decade at the regional scale. This vertical zonal process was modulated by topography-induced differences in local hydrothermal conditions. Thus, the ASVA shrank mainly in its lower parts with mild and sunny slopes. Annual maximum NDVI in the transition zone increased significantly and showed a stronger positive correlation with significantly increasing temperature than insignificant precipitation variations during 1990–2015. The ASVA shrinkage and up-shifting of its boundary were attributed to climate warming, which facilitated the upper part of alpine meadow in the EQLM by releasing the low temperature limitation on vegetation growth.

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Debris-cover on glaciers in the Austrian Alps. Regional patterns, Changes and Significance.

10.5194/egusphere-egu21-2036 ◽

2021 ◽

Author(s):

Jan-Christoph Otto ◽

Fabian Fleischer ◽

Robert Junker ◽

Daniel Hölbling

Keyword(s):

Climate Warming ◽

Regional Scale ◽

Eastern Alps ◽

High Elevation ◽

Regional Variability ◽

Mountain Areas ◽

Regional Patterns ◽

Austrian Alps ◽

Glacier System ◽

Debris Cover

Debris cover on glaciers is an important component of glacial systems as it influences climate-glacier dynamics and thus the lifespan of glaciers. Increasing air temperatures, permafrost thaw, as well as rock faces freshly exposed by glacier downwasting results in increased rockfall activity and debris input into the glacier system. In the ablation zone, negative mass balances result in an enhanced melt-out of englacial debris to the glacier system. Glacier debris cover thus represents a signal of climate warming in mountain areas. To assess the temporal development of debris on glaciers of the Eastern Alps, Austria, we mapped debris cover on 255 of the more than 800 glaciers using Landsat data at three time steps between 1996 and 2015. We applied a ratio-based threshold classification technique using existing glacier outlines. The debris cover evolution was subsequently compared to glacier changes. Glacier and glacier catchment characteristics have been analysed using GIS techniques and statistics in order to investigate potential reasons for debris cover change.Across the Austrian Alps debris cover increased by more than 10% between 1996 and 2015 while glaciers retreated significantly in response to climate warming. Debris cover distribution shows regional variability with some mountain ranges being characterised by mean debris cover on glaciers of up to 75%. We also observed a general rise of mean elevation of debris cover on glaciers in Austria. Debris cover distribution and dynamics are highly variable due to topographic, lithological and structural settings that determine the amount of debris delivered to and stored in the glacier system. Lower relative debris cover is observed on glaciers with higher mean and maximum elevation. Additionally, glaciers with increased mean slope, as well as catchments with large areas of steep slopes and a high elevation range of these slopes tend to show higher debris cover. Both parameters indicate that the influence of the steep rockwalls in the glacier catchment is a first order control on debris cover at regional scale. We can also show that catchments with a high percentage of potential permafrost distribution contain glaciers with a higher relative debris cover.Despite strong variation in debris cover, all glaciers investigated melted at increasing rates. We conclude that the retarding effects of debris cover on the mass balance and melt rate of Austrian glaciers is strongly subdued compared to other mountain areas. The study indicates that if this trend continues many glaciers in Austria may become fully debris covered in the future. However, since debris cover seems to have little impact on melt rates in the study area it will therefore not lead to a prolonged existence of debris-covered ice compared to clean ice glaciers.

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The Response of Culturally Important Plants to Experimental Warming and Grazing in Pakistan Himalayas

10.1101/2020.08.07.241117 ◽

2020 ◽

Author(s):

Saira Karimi ◽

Muhammad Ali Nawaz ◽

Saadia Naseem ◽

Ahmed Akrem ◽

Olivier Dangles ◽

...

Keyword(s):

Medicinal Plants ◽

Climate Warming ◽

Regional Scale ◽

Wild Plants ◽

Plant Responses ◽

Cultural Systems ◽

Experimental Treatments ◽

Determining Factor ◽

Target Plant

AbstractThe response of wild plants towards climate warming is taxa specific, but overgrazing could also be a determining factor for the alpine ecosystems. Overgrazing and climate warming are important drivers of alpine grassland degradation worldwide. Local indigenous peoples will be the first impacted by such degradation due to impacts on animal production and the availability of local medicinal plants. Studies on plant responses to overgrazing and climate change are rarely performed to assess threats to these biological and cultural systems. Long-term observations or manipulative experiments are promising, but rarely use strategies to evaluate the sensitivity and vulnerability of such ecosystems to climatic change. We studied the combined effects of overgrazing and increased temperatures on culturally important medicinal plants of Khunjerab National Park, Pakistan. Three experimental treatments were used (control, warming through an open-top chamber, and exclusion of grazing animals vs. the control). These experimental plots were installed at different elevations (3352-4969 m) and were monitored routinely. Grazing reduced vegetation cover & biomass by 2.3% and 6.26%, respectively, but that was not significant due to the high variability among study plots. However, warming significantly increased the overall percentage cover and biomass of all target plant species, ranging from 1±0.6% in Bistorta officinalis to 18.7 ± 4.9% in Poa alpina. Thus, warming may increase the availability of therapeutic plants for indigenous people while overgrazing would have deteriorating effects locally. This research illustrates that vegetation sensitivity to warming and overgrazing is likely to affect man– environment relationships, and traditional knowledge on a regional scale.

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Precipitation projections using a spatiotemporally distributed method: a case study in the Poyang Lake watershed based on the MRI-CGCM3

Hydrology and Earth System Sciences ◽

10.5194/hess-23-1649-2019 ◽

2019 ◽

Vol 23 (3) ◽

pp. 1649-1666 ◽

Cited By ~ 5

Author(s):

Ling Zhang ◽

Xiaoling Chen ◽

Jianzhong Lu ◽

Xiaokang Fu ◽

Yufang Zhang ◽

...

Keyword(s):

Climate Warming ◽

General Circulation ◽

Poyang Lake ◽

Global Climate Model ◽

Regional Scale ◽

Resource Planning ◽

Dry Season ◽

Wet Season ◽

Basin Scale ◽

Precipitation Changes

Abstract. To bridge the gap between large-scale GCM (global climate model) outputs and regional-scale climate requirements of hydrological models, a spatiotemporally distributed downscaling model (STDDM) was developed. The STDDM was done in three stages: (1) up-sampling grid-observations and GCM simulations for spatially continuous finer grids, (2) creating the mapping relationship between the observations and the simulations differently in space and time, and (3) correcting the simulation and producing downscaled data to a spatially continuous grid scale. We applied the STDDM to precipitation downscaling in the Poyang Lake watershed using the MRI-CGCM3 (Meteorological Research Institute Coupled Ocean–Atmosphere General Circulation Model 3), with an acceptable uncertainty of ≤ 4.9 %. Then we created future precipitation changes from 1998 to 2100 (1998–2012 in the historical scenario and 2013–2100 in the RCP8.5 scenario). The precipitation changes increased heterogeneities in temporal and spatial distribution under future climate warming. In terms of temporal patterns, the wet season become wetter, while the dry season become drier. The frequency of extreme precipitation increased, while that of the moderate precipitation decreased. Total precipitation increased, while rainy days decreased. The maximum continuous dry days and the maximum daily precipitation both increased. In terms of spatial patterns, the dry area exhibited a drier condition during the dry season, and the wet area exhibited a wetter condition during the wet season. Analysis with temperature increment showed precipitation changes can be significantly explained by climate warming, with p<0.05 and R≥0.56. The precipitation changes indicated that the downscaling method is reasonable, and the STDDM could be successfully applied to the basin-scale region based on a GCM. The results implied an increasing risk of floods and droughts under global warming, which were a reference for water balance analysis and water resource planning.

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Koreans across the Sea: Migration of Laborers to the Metropole, 1910–1937

European Journal of Korean Studies ◽

10.33526/ejks.20191901.161 ◽

2019 ◽

pp. 161-200

Author(s):

Mikwi Cho

Keyword(s):

Capital Accumulation ◽

Regional Scale ◽

Living Conditions ◽

Colonial Period ◽

Global City ◽

Japanese Empire ◽

Chain Migration ◽

Free Mobility

This paper is concerned with Korean farmers who were transformed into laborers during the Korean colonial period and migrated to Japan to enhance their living conditions. The author’s research adopts a regional scale to its investigation in which the emergence of Osaka as a global city attracted Koreans seeking economic betterment. The paper shows that, despite an initial claim to permit the free mobility of Koreans, the Japanese empire came to control this mobility depending on political, social, and economic circumstances of Japan and Korea. For Koreans, notwithstanding poverty being a primary trigger for the abandonment of their homes, the paper argues that their migration was facilitated by chain migration and they saw Japan as a resolution to their economic hardships in the process of capital accumulation by the empire.

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