Dynamics of a Giant Slow Landslide Along the Coast of the Aral Sea (Central Asia)

The mountains of Central Asia, extending over 7000 m a.s.l. and accommodating diverse and complex natural and managed systems, are very vulnerable to climate change. They support valuable environmental functions and provide key ecosystem goods and services to the arid downstream regions which strongly depend on the melting snowpack and glaciers for the provision of water by the transboundary rivers starting in the mountains. Strong climate change adaptation (CCA) action is required to increase resilience of the vulnerable, low-income communities in the region. Our knowledge of the CCA actions in the mountains of Central Asia is limited in comparison with other mountainous regions. The aim of this study is to assess the existing adaptation projects and publications and to identify gaps in adaptation efforts by conducting a systematic review of the peer-reviewed literature published in English language. To be selected, the papers had to comply with the following criteria: (i) publication between 2013 and 2019; (ii) explicit focus on CCA in the mountain ranges of Central Asia; (iii) explanation of adaptation options; (vi) a clear methodology of deriving suitable adaptation options. Following the initial screening and subsequent reading of the publications, complying with the specified criteria, 33 peer-reviewed articles were selected for final analysis. This is considerably lower than the number of publications on the European Alps, Hindu-Kush &#8211; Himalayas, and the Andes. The number of publications on Central Asian mountains has declined since 2013.The research is heavily focused on the problem of water resources, especially water availability at present and in the future 70 % of the analysed papers addressing these issues. These are followed by the papers considering adaptation in agriculture and in managing biodiversity. A critical finding is the lack of publications on adaptation to hazards and disasters including glacier outburst floods, mudflow, and landslides which are common and comparatively well-researched hazards in the Central Asian mountains, experiencing rapid deglaciation. About 50 % of the papers address the transboundary nature of the impacts of climate changes on water resources and land management reflecting the transboundary nature of the Central Asian catchments and the tensions which exist across the region but are especially prominent in the Aral Sea basin.We conclude that while there is ample evidence of climate change and its impacts in the mountains of Central Asia and many publications mention the need for adaptation, a very limited number of publications explicitly focus on CCA and how it can be delivered.

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Post-Soviet changes in irrigated crop production in the Amu Darya Basin

10.5194/egusphere-egu21-16266 ◽

2021 ◽

Author(s):

Daniel Müller ◽

Andrey Dara ◽

Christopher Krause ◽

Mayra Daniela Peña-Guerrero ◽

Tillman Schmitz ◽

...

Keyword(s):

Water Resources ◽

Central Asia ◽

Crop Production ◽

Large Scale ◽

Aral Sea ◽

Crop Cultivation ◽

Amu Darya ◽

Crop Type ◽

Water Scarce ◽

Hydrological Droughts

Water withdrawals for irrigated crop production constitute the largest global consumer of blue water resources. Monitoring the dynamics of irrigated crop cultivation allows to track changes in water consumption of irrigated cropping, which is particularly paramount in water-scarce arid and semi-arid areas. We analyzed changes in irrigated crop cultivation along with occurrence of hydrological droughts for the Amu Darya river basin of Central Asia (534,700 km2), once the largest tributary river to the Aral Sea before large-scale irrigation projects have grossly reduced the amount of water that reaches the river delta. We used annual and seasonal spectral-temporal metrics derived from Landsat time series to quantify the three predominant cropping practices in the region (first season, second season, double cropping) for every year between 1988 and 2020. We further derived unbiased area estimates for the cropping classes at the province level based on a stratified random sample (n=2,779). Our results reveal a small yet steady decrease in irrigated second season cultivation across the basin. Regionally, we observed a gradual move away from cotton monocropping in response to the policy changes that were instigated since the mid-1990s. We compared the observed cropping dynamics to the occurrence of hydrological droughts, i.e., periods with inadequate water resources for irrigation. We find that areas with higher drought risks rely more on irrigation of the second season crops. Overall, our analysis provides the first fine-scale, annual crop type maps for the irrigated areas in the Amu Darya basin. The results shed light on how institutional changes and hydroclimatic factors that affect land-use decision-making, and thus the dynamics of crop type composition, in the vast irrigated areas of Central Asia.

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The Aralkum, a Man-Made Desert on the Desiccated Floor of the Aral Sea (Central Asia): General Introduction and Aims of the Book

Ecological Studies - Aralkum - a Man-Made Desert ◽

10.1007/978-3-642-21117-1_1 ◽

2011 ◽

pp. 1-9

Author(s):

S-W. Breckle ◽

W. Wucherer

Keyword(s):

Central Asia ◽

Aral Sea ◽

General Introduction

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Changes in area and water volume of the Aral Sea in the arid Central Asia over the period of 1960–2018 and their causes

CATENA ◽

10.1016/j.catena.2020.104566 ◽

2020 ◽

Vol 191 ◽

pp. 104566 ◽

Cited By ~ 5

Author(s):

Xuewen Yang ◽

Ninglian Wang ◽

An'an Chen ◽

Jing He ◽

Ting Hua ◽

...

Keyword(s):

Central Asia ◽

Aral Sea ◽

Water Volume ◽

Arid Central Asia

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A Solution to the Aral Sea Crisis? Sustainable Water Use in Central Asia

Water and Environment Journal ◽

10.1111/j.1747-6593.2000.tb00252.x ◽

2000 ◽

Vol 14 (3) ◽

pp. 213-218 ◽

Cited By ~ 1

Author(s):

T. Hannan

Keyword(s):

Central Asia ◽

Water Use ◽

Aral Sea ◽

Sustainable Water Use

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Anthropogenic Influences on Environmental Changes of Lake Bosten, the Largest Inland Freshwater Lake in China

Sustainability ◽

10.3390/su12020711 ◽

2020 ◽

Vol 12 (2) ◽

pp. 711 ◽

Cited By ~ 4

Author(s):

Wen Liu ◽

Long Ma ◽

Jilili Abuduwaili

Keyword(s):

Central Asia ◽

Lake Sediments ◽

Human Activities ◽

Environmental Changes ◽

Living Environment ◽

Water Levels ◽

Aral Sea ◽

Anthropogenic Factors ◽

Large Spatial Scale ◽

The 1960S

A short lacustrine sediment core (41 cm) from Lake Bosten in arid central Asia was used to investigate the environmental changes that occurred in the past ≈150 years based on the superposition of climate and anthropogenic factors. Geochemical elements, total organic carbon (TOC) and nitrogen (TN), and stable isotope data (δ13Corg and δ15N) were used to identify abnormal environmental changes. The average C/N ratio in the sediments of Lake Bosten suggested that the organic matter in lake sediments was mainly from aquatic plants. The δ13Corg and δ15N in the lake sediments mainly reflect changes in the structure of the lake’s ecosystem. Before the 1960s, the primary productivity of the lake was relatively low with a relatively stable lake water environment. From the 1960s to the mid-1980s, the lake’s ecosystem was closely related to a significant decline in water levels caused by human activities and an increase in salinity. From the late 1980s to ≈2000, the aquatic plant structure of Lake Bosten did not change significantly. After 2000, the upper part of the sedimentary record suggested enhanced productivity due to urban and industrial development in the catchment area. However, sedimentary perspectives of the responses of different environmental proxies in sediments to human activities were anisochronous, and the increasing heavy metal (Pb and Cu) and P accumulations appeared in 1970, reflecting heightened human impacts. Through the comparison between the Aral Sea and Lake Bosten, it was inferred that, under the intervention of human activities, the lake experienced a completely different evolution trend. Humans, as geological agents, should protect our living environment while satisfying social development. The results will provide an important supplement to a large spatial scale study of the influences of human activities on the environment in Central Asia, which also has some significant implications for the protection of the ecological environment and the realization of sustainable development in arid regions.

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Quantitative Soil Wind Erosion Potential Mapping for Central Asia Using the Google Earth Engine Platform

Remote Sensing ◽

10.3390/rs12203430 ◽

2020 ◽

Vol 12 (20) ◽

pp. 3430

Author(s):

Wei Wang ◽

Alim Samat ◽

Yongxiao Ge ◽

Long Ma ◽

Abula Tuheti ◽

...

Keyword(s):

Wind Speed ◽

Central Asia ◽

Wind Erosion ◽

Large Scale ◽

Google Earth ◽

Geospatial Data ◽

Aral Sea ◽

Erosion Modeling ◽

Soil Wind Erosion ◽

Google Earth Engine

A lack of long-term soil wind erosion data impedes sustainable land management in developing regions, especially in Central Asia (CA). Compared with large-scale field measurements, wind erosion modeling based on geospatial data is an efficient and effective method for quantitative soil wind erosion mapping. However, conventional local-based wind erosion modeling is time-consuming and labor-intensive, especially when processing large amounts of geospatial data. To address this issue, we developed a Google Earth Engine-based Revised Wind Erosion Equation (RWEQ) model, named GEE-RWEQ, to delineate the Soil Wind Erosion Potential (SWEP). Based on the GEE-RWEQ model, terabytes of Remote Sensing (RS) data, climate assimilation data, and some other geospatial data were applied to produce monthly SWEP with a high spatial resolution (500 m) across CA between 2000 and 2019. The results show that the mean SWEP is in good agreement with the ground observation-based dust storm index (DSI), satellite-based Aerosol Optical Depth (AOD), and Absorbing Aerosol Index (AAI), confirming that GEE-RWEQ is a robust wind erosion prediction model. Wind speed factors primarily determined the wind erosion in CA (r = 0.7, p < 0.001), and the SWEP has significantly increased since 2011 because of the reversal of global terrestrial stilling in recent years. The Aral Sea Dry Lakebed (ASDLB), formed by shrinkage of the Aral Sea, is the most severe wind erosion area in CA (47.29 kg/m2/y). Temporally, the wind erosion dominated by wind speed has the largest spatial extent of wind erosion in Spring (MAM). Meanwhile, affected by the spatial difference of the snowmelt period in CA, the wind erosion hazard center moved from the southwest (Karakum Desert) to the middle of CA (Kyzylkum Desert and Muyunkum Desert) during spring. According to the impacts of land cover change on the spatial dynamic of wind erosion, the SWEP of bareland was the highest, while that of forestland was the lowest.

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