scholarly journals Environmental resilience of rangeland ecosystems: assessment drought indices and vegetation trends on arid and semi-arid zones of Central Asia

Author(s):  
Dildora Aralova ◽  
Kristina Toderich ◽  
Ben Jarihani ◽  
Dilshod Gafurov ◽  
Liliya Gismatulina ◽  
...  
2021 ◽  
Author(s):  
Aristeidis Varis ◽  
Christopher Miller ◽  
Patrick Cuthbertson ◽  
Abay Namen ◽  
Zhaken Taimagambetov ◽  
...  

Central Asian caves with Palaeolithic deposits are few but they provide a rich record of human fossils and cultural assemblages that has been used to model Late Pleistocene hominin dispersals. However, previous research has not yet systematically evaluated the formation processes that influence the frequency of Palaeolithic cave sites in the region. To address this deficiency, we combined field survey and micromorphological analyses in the piedmont zone of south Kazakhstan. Here we present our preliminary results focusing on selected sites of the Qaratau mountains. Sediment cover varies among the surveyed caves and loess-like sediments dominate the cave sequences. The preservation of cave deposits is influenced by reworking of cave sediments within the caves but also by the broader erosional processes that shape semi-arid landscapes. Ultimately, deposits of potentially Pleistocene age are scarce. Our study provides new data in the geoarchaeologically neglected region of Central Asia and demonstrates that micromorphology has great analytical potential even within the limitations of rigorous survey projects. We outline some of the processes that influence the formation and preservation of cave deposits inKazakhstan, as well as broader implications for the distribution of Palaeolithic cave sites in Central Asia and other semi-arid environments.


Hydrology ◽  
2019 ◽  
Vol 6 (3) ◽  
pp. 75 ◽  
Author(s):  
Ahmad Nemati ◽  
Seyed Hossein Ghoreishi Najafabadi ◽  
Gholamreza Joodaki ◽  
S. Saeid Mousavi Nadoushani

Drought monitoring needs comprehensive and integrated meteorological and hydrologic data. However, such data are generally not available in extensive catchments. The present study aimed to analyze drought in the central plateau catchment of Iran using the terrestrial water storage deficit index (TSDI). In this arid catchment, the meteorological and hydrologic observed data are scarce. First, the time series of terrestrial water storage changes (TWSC) obtained from the gravity recovery and climate experiment (GRACE) was calculated and validated by the water budget output. Then, the studied area was divided into semi-arid, arid, and hyper-arid zones and the common drought indices of SPI and RDIe within a timescale of 3, 6, and 12 months were calculated to compare the results obtained from the TSDI by using the meteorological data of 105 synoptic stations. Based on the results, the study area experienced a drought with extreme severity and expansion during 2007–2008. The drought spatial distribution map obtained from three indices indicated good conformity. Based on the maps, the severity, duration, and frequency of drought in the semi-arid zone were greater than that in other zones, while no significant drought occurred in the hyper-arid zone. Furthermore, the temporal distribution of drought in all three zones indicated that the TSDI could detect all short- and long-term droughts. The study results showed that the TSDI is a reliable, integrated, and comprehensive index. Using this index in arid areas with little field data led to some valuable results for planning and water resource management.


2008 ◽  
Vol 30 (1) ◽  
pp. 29 ◽  
Author(s):  
Dominic Brown ◽  
John Taylor ◽  
Martin Bell

In recent years, with the formation of organisations such as the Desert Knowledge Cooperative Research Centre, social science interest in the Australian desert has re-surfaced with a research emphasis that is focused on creating sustainable futures for the region. One consequence of this is a demand for detailed demographic information to allow an assessment of different quanta of need in social and economic policy, and for assessment of the impact of these in environmental policy. However, demographic analysis on human populations in the desert to date has attracted very little research attention. In this paper we begin to address this lack of analysis by focusing on the populations, both aboriginal and non-aboriginal, of the arid and semi-arid zones of Australia. We extend earlier analysis by including for the first time demographic information on the semi-arid as well as the arid zone to establish the spatial pattern of population growth within the whole desert area drawing attention to the resulting settlement structure as an outcome of prevailing social, cultural and economic conditions. By examining population structure and demographic components of population change we also present for the first time population projections for the semi-arid zone and, therefore, in combination with the arid zone, for the entire Australian desert. All of this provides a basis for considering social and economic policy implications and the nature of underlying processes that drive change in this region.


Author(s):  
Hanamant M. Halli ◽  
S.S. Rathore ◽  
N. Manjunatha ◽  
Vinod Kumar Wasnik

2020 ◽  
Author(s):  
Alia Ahmed ◽  
Amjad Hameed ◽  
Shazia Saeed

AbstractRecent focus is on analysis of biological activities of extracts from plant species. Zygophyllaceae is exceedingly important angiosperm family with many taxa being used in folk medicines widely dispersed in arid and semi-arid zones of Balochistan, Pakistan. Only a small proportion of them have been scientifically analyzed and many species are nearly facing extinction. Therefore present investigation explores the biochemical and bioactive potential of fourteen folk medicinal plants usually used for treatments of different ailments. Fresh aerial parts of nine taxa and two fruit samples were collected from plants growing in arid and semi-arid zones of Balochistan and analyzed for enzymatic, non-enzymatic and other biochemical activities. Higher phytochemical activities were detected in the aerial parts. Superoxide dismutase was detected maximum in Fagonia indica, (184.7±5.17 units/g), ascorbate peroxidase in Tribulus longipetalus subsp. longipetalus (947.5±12.5 Units/g), catalase and peroxidase was higher in Peganum harmala (555.0±5.0 and 2597.8±0.4 units/g respectively). Maximum esterase and alpha amylase activity was found in Zygophyllum fabago (14.3±0.44 and 140±18.8 mg/g respectively). Flavonoid content was high in T. longipetalus subsp. longipetalus (666.1±49 μg/ml). The highest total phenolic content and tannin was revealed in F. olivieri (72125±425 and 37050±1900 μM/g. respectively). Highest value of ascorbic acid was depicted in F. bruguieri var. rechingeri (448±1.5 μg/g). Total soluble Proteins and reducing sugars were detected higher in P. harmala (372.3±54 and 5.9±0.1 mg/g respectively). Maximum total antioxidant capacity (TAC) was depicted in Z. simplex (16.9±0.01 μM/g). Pigment analysis exhibited the high value of lycopene and total carotenoids in T. terrestris (7.44±0.2 and 35.5±0.0 mg/g respectively). Chlorophyll a, b and total chlorophyll content was found maximum in T. longipetalus subsp. pterophorus (549.1±9.9, 154.3±10 and 703.4±20.2 ug/g respectively). All taxa exhibited anti-inflammatory activity as well as anti-diabetic inhibitory potential. Seed extracts of Zygophyllum eurypterum (96%) exhibited highest inhibitory potential, along with twelve other taxa of Zygophyllaceae indicated (96-76%) activity when compared with the standard drug diclofenac sodium (79%). Seeds of T. longipetalus subsp. longipetalus (85%) exhibited the highest anti-diabetic activity; other eleven taxa also exhibited inhibitory activity of α-amylase ranging from (85-69%) compared with Metformin (67%) standard drug. Phytochemical screening revealed that selected taxa proved to be the potential source of natural antioxidants and could further be explored for in-vivo studies and utilized in pharmaceutical industries as potent therapeutic agents validating their ethno-pharmacological uses.


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