Recent trends of temperature change under hot and cold desert climates: Comparing the Sahara (Libya) and Central Asia (Xinjiang, China)

2011 ◽  
Vol 75 (11) ◽  
pp. 1105-1113 ◽  
Author(s):  
B. Mamtimin ◽  
A.M.M. Et-Tantawi ◽  
D. Schaefer ◽  
F.X. Meixner ◽  
M. Domroes
Keyword(s):  
Central Asia ◽  
Temperature Change ◽  
Cold Desert ◽  
Recent Trends

Germination and persistence in soil of the dimorphic diaspores of Atriplex centralasiatica

2016 ◽  
Vol 26 (3) ◽  
pp. 273-283 ◽  
Author(s):  
Rui Zhang ◽  
Yan Rong Wang ◽  
Jerry M. Baskin ◽  
Carol C. Baskin ◽  
Kai Luo ◽  
...  
Keyword(s):  
Central Asia ◽  
Soil Surface ◽  
Potassium Nitrate ◽  
Flowering Plants ◽  
Light Regime ◽  
Cold Desert ◽  
Natural Dispersal ◽  
Germination Requirements ◽  
Desert Halophyte ◽  
Constant Dark

AbstractThe fruit plus accessory parts, and thus not only the fruit or seed, is the diaspore in some species of flowering plants. Atriplex centralasiatica, a summer annual salt-secreting cold-desert halophyte of central Asia that produces flat and humped diaspores, is such a species. The dispersal/germination units of this diaspore-heteromorphic species are fruits enclosed in persistent ‘bracteoles’. Germination of black and brown fruits (i.e. ‘bracteoles’ removed) of this species has been studied in some detail previously, but little attention has been given to the germination biology of the intact diaspores. The aim of this study was to compare the germination biology of the intact diaspores of A. centralasiatica, and their fates in the field during 12 months on the soil surface and buried at 5-cm depth. Fresh flat diaspores germinated to 42.7–51.3% in light (12-h photoperiod) and to 16.0–59.3% in constant dark, over a temperature range of 15–20/30°C, while no freshly matured humped diaspores did so under any temperature/light regime. Neither gibberellin (GA3) nor potassium nitrate (KNO3) had an effect on germination of either diaspore. Both diaspores readily imbibed water, and removal of ‘bracteoles’ released most of the dormancy. Thus, the ‘bracteoles’ are primarily responsible for diaspore dormancy in A. centralasiatica. Humped diaspores persisted for a longer period in the soil than flat ones. The germination requirements of intact natural dispersal/germination units of A. centralasiatica differ from those previously reported for fruits of this species.

scholarly journals Elevation and Climate Effects on Vegetation Greenness in an Arid Mountain-Basin System of Central Asia

2020 ◽  
Vol 12 (10) ◽  
pp. 1665 ◽  
Author(s):  
Xiaoli Tai ◽  
Howard E. Epstein ◽  
Bo Li
Keyword(s):  
Central Asia ◽  
Temperature Change ◽  
Vegetation Index ◽  
Positive Response ◽  
Regional Scale ◽  
Warming Trend ◽  
Practical Significance ◽  
Elevation Gradients ◽  
Vegetation Greenness ◽  
Response To Temperature

Mountain-basin systems (MBS) in Central Asia are unique and complex ecosystems, wherein their elevation gradients lead to high spatial heterogeneity in vegetation and its response to climate change. Exploring elevation-dependent vegetation greenness variation and the effects of climate factors on vegetation has important theoretical and practical significance for regulating the ecological processes of this system. Based on the MODIS NDVI (remotely sensed normalized difference vegetation index), and observed precipitation and temperature data sets, we analyzed vegetation greenness and climate patterns and dynamics with respect to elevation (300–3600 m) in a typical MBS, in Altay Prefecture, China, during 2000–2017. Results showed that vegetation exhibited a greening (NDVI) trend for the whole region, as well as the mountain, oasis and desert zones, but only the desert zone reached significant level. Vegetation in all elevation bins showed greening, with significant trends at 400–700 m and 2600–3500 m. In summer, lower elevation bins (below 1500 m) had a nonsignificant wetting and warming trend and higher elevation bins had a nonsignificant drying and warming trend. Temperature trend increased with increasing elevation, indicating that warming was stronger at higher elevations. In addition, precipitation had a significantly positive coefficient and temperature a nonsignificant coefficient with NDVI at both regional scale and subregional scale. Our analysis suggests that the regional average could mask or obscure the relationship between climate and vegetation at elevational scale. Vegetation greenness had a positive response to precipitation change in all elevation bins, and had a negative response to temperature change at lower elevations (below 2600 m), and a positive response to temperature change at higher elevations. We observed that vegetation greenness was more sensitive to precipitation than to temperature at lower elevations (below 2700 m), and was more sensitive to temperature at higher elevations.

scholarly journals Temperature Changes in Central Asia from 1979 to 2011 Based on Multiple Datasets*

2014 ◽  
Vol 27 (3) ◽  
pp. 1143-1167 ◽  
Author(s):  
Zengyun Hu ◽  
Chi Zhang ◽  
Qi Hu ◽  
Hanqin Tian
Keyword(s):  
Central Asia ◽  
Temperature Change ◽  
Air Temperature ◽  
Surface Air Temperature ◽  
Early Years ◽  
Semiarid Region ◽  
Climate Variations ◽  
Near Surface ◽  
Local Climate ◽  
Multiple Datasets

Abstract The arid and semiarid region in central Asia is sensitive and vulnerable to climate variations. However, the sparse and highly unevenly distributed meteorological stations in the region provide limited data for understanding of the region’s climate variations. In this study, the near-surface air temperature change in central Asia from 1979 to 2011 was examined using observations from 81 meteorological stations, three local observation validated reanalysis datasets of relatively high spatial resolutions, and the Climate Research Unit (CRU) dataset. Major results suggested that the three reanalysis datasets match well with most of the local climate records, especially in the low-lying plain areas. The consensus of the multiple datasets showed significant regional surface air temperature increases of 0.36°–0.42°C decade−1 in the past 33 years. No significant contributions from declining irrigation and urbanization to temperature change were found. The rate is larger in recent years than in the early years in the study period. Additionally, unlike in many regions in the world, the temperature in winter showed no increase in central Asia in the last three decades, a noticeable departure from the global trend in the twentieth century. The largest increase in surface temperature was occurring in the spring season. Analyses further showed a warming center in the middle of the central Asian states and weakened temperature variability along the northwest–southeast temperature gradient from the northern Kazakhstan to southern Xinjiang. The reanalysis datasets also showed significant negative correlations between temperature increase rate and elevation in this complex terrain region.

scholarly journals Afghanistan as an emerging regional energy hub

2020 ◽  
pp. 10-14
Author(s):  
Mir Sayed Shah Danish ◽  
Tomonobu Senjyu ◽  
Hameedullah Zaheb ◽  
Najib Rahman Sabory ◽  
Mikaeel Ahamadi ◽  
...  
Keyword(s):  
Central Asia ◽  
Political Stability ◽  
Trade Policies ◽  
Energy Hub ◽  
Regional Energy ◽  
Energy Trade ◽  
Recent Trends ◽  
Balance Energy ◽  
Energy Provider ◽  
Energy Sharing

The enormous potential supply of energy in central Asia offers an excellent opportunity to establish international energy-sharing agreements, mitigate political instability, and improve regional socio-economic development. Pakistan and India have increasingly relied on energy imported from Middle and Central Asia to meet frequent energy shortages. Afghanistan has played a central role in recent efforts to balance energy trade among regional countries with an emerging opportunity as an emerging energy hub. This study considers what energy trade policies and strategies are needed to transform Afghanistan from energy consumer to energy provider. This analysis summarizes multi-disciplinary approaches that target geopolitics, economic, trade, management, institutional, environmental, and technical aspects. This study avoided a commentary description of the subject. The overriding objective of this study is addressing key solutions to enable Afghanistan as a leading stakeholder of the energy hub in the region countries. The finding of this study is outlined in 30 recommendations. Beneficiaries and stakeholders also express increasing concern about Afghanistan’s current security and political stability. This brief study can inform students, researchers, scholars, and interested policymakers with the recent trends and future outlook.

scholarly journals Is the Life History Flexibility of Cold Desert Annuals Broad Enough to Cope with Predicted Climate Change? The Case of Erodium oxyrhinchum in Central Asia

Biology ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 780
Author(s):  
Huiliang Liu ◽  
Yanfeng Chen ◽  
Lingwei Zhang ◽  
Jerry M. Baskin ◽  
Carol C. Baskin ◽  
...  
Keyword(s):  
Climate Change ◽  
Life History ◽  
Central Asia ◽  
Seed Dormancy ◽  
Morphological Characters ◽  
Cold Desert ◽  
Nw China ◽  
Desert Annual ◽  
Vegetative And Reproductive Growth ◽  
Projected Changes

Interannual seasonal variability in precipitation may strongly affect the life history and growth of desert annual plants. We compared the effects of dry and wet springs and dry and wet autumns on growth and F2 seed dormancy of plants from spring (SG)- and autumn (AG)-germinated seeds of the cold desert annual Erodium oxyrhinchum. Vegetative and reproductive growth and F2 seed dormancy and germination were monitored from September 2016 to November 2020 in the sandy Gurbantunggut Desert in NW China in Central Asia. Dry autumns decreased the density of AG plants, and dry springs decreased the density of SG plants and growth of SG and AG plants. In dry springs, SG plants were more sensitive to precipitation than AG plants, while in wet springs SG and AG plants had similar responses to precipitation. During growth in both dry and wet springs, most morphological characters of SG and AG plants initially increased rapidly in size/number and then plateaued or decreased, except for SG plants in dry springs. In dry springs, most morphological characters of AG plants were larger or more numerous than those of SG plants, and they were larger/more numerous for SG plants in wet than in dry springs. The percentage biomass allocated to reproduction in SG plants was slightly higher in a wet than in a dry spring. A much higher proportion of dormant seeds was produced by AG plants in a wet spring than in a dry spring. Projected changes in precipitation due to climate change in NW China are not likely to have much of an effect on the biology of this common desert annual plant.

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