Great Indian Thar Desert Research Articles

Identification of Playa Lakes and tracking their evolution pathways using geochemical models in the Great Indian Thar desert

Playa Lakes of the great Indian Thar desert are unique and intricate systems with pronounced scientific and ecological significance. In this study, the combined use of geospatial and field data assisted in depicting and understanding the changes within these natural systems. The purpose of this study is to provide a comprehensive dataset of Playa Lakes, which can help with an overall understanding of playas from a geochemical, ecological, and economic perspective. The 1163 surface depressions were accounted for as possible playas considering the threshold area of >5 km2. A total of 42 representative surface water samples were collected from the selected playas (Sambhar, Didwana, Pachpadra, and Pokhran) and hydrochemical analysis was carried out to identify the geochemical evolution of these playas. The major water types were Na-Cl and Na-Cl-SO4 type. Hardie and Eugster's model was used to explain the possible sequence of evolutionary pathways and brine shifts in the selected playas. Simulated evaporation modeling suggests precipitation of major evaporites (chlorides, carbonates, and sulphates) during progressive evaporation. Surface sediment analysis (X-ray diffraction) confirmed the presence of calcite, halite, and dolomite minerals in the playa sediments. The greatest economic value of these playas may be mineral production and providing food and habitat for migratory birds, though conservation and policy intervention is required for their sustainable utilization.

Geomicrobial Exploration of Sulfur Oxidizing Bacteria Indigenous to Kapurdi and Jalipa Lignite Mine Site, Rajasthan

Abstract The metabolic versatility and potential of microbes enables their survival and growth in harsh condition such as sites ravaged by mining activities. The Kapurdi lignite deposit of the Barmer Basin is one of the important Tertiary lignite deposits underlying the Great Indian Thar desert in the north-western part of Rajasthan. The diversity of culturable sulfur oxidizing bacteria (SOB) in Kapurdi and Jalipa lignite mine site, Barmer, Rajasthan was assessed in this study. Bacteria were isolated by plating on selective thiosulfate mineral media, and dominant isolates were identified from their physiological characteristics and 16S rRNA gene sequences. The obligate chemolithotrophic SOB were identified as Thermithiobacillus sp. strain KO11, KO12, KO13 (OP788122, OP788123, OP788124). Whereas heterotrophic SOB was identified as Bacillus sp.strain KO1 (OP788112), Bacillus sp. strain KO2 (OP788113), Bacillus sp.strain KO3 (OP788114), Enterobacter sp.strain KO4, KO5, KO6, KO9 (OP788115, OP788116, OP788117, OP788120), Leclercia sp. Strain KO7 (OP788118), Pantoea sp. strain KO8(OP788119), and Rhodococcussp.strain KO10 (OP788121). The culture condition was optimized for the two most potential SOB i.e., Thermithiobacillus sp. strain KO11 and Leclercia sp. strain KO7. Both the isolates grew well and produced maximum amount of sulfate in thiosulfate mineral media at pH 8.0 and with 40 mM of thiosulfate substrate. Thermithiobacillus sp. strain KO11 had the optimum growth at 45°C indicating its thermophillic nature whereas, Leclercia sp. strain KO7 had optimum growth at 35°C. This study significantly enhances our knowledge of native bacteria in mining impacted environments and their role in biogeochemical cycling of sulfur.

DESERT SOLAR POWER INDIA: A SYSTEMATIC STUDY OF POTENTIAL DEVELOPMENT OF SOLAR POWER IN THE INDIAN DESERT

The deserts of Rajasthan have long been known for their spare beauty and their intense sunshine. Now that sun is being turned into a surge of solar power expansion that may one day power not just Rajasthan but a wide swath of India with clean energy. Rajasthan, with its 300 days a year of sunshine and relatively cheap desert land, has set a goal even more ambitious than Indias. In this years state budget, the newly formed state government announced it hoped to install 25,000 megawatts of solar energy in the state within the next five years, and infrastructure to transmit that power to the national grid. Rajasthan is no newcomer to renewable energy. Since the 1990s, the state has been home to a range of wind energy projects, with about 2,800 megawatts of wind capacity now installed, out of an estimated potential capacity of 5,000 megawatts. Altogether wind power in Rajasthan accounts for about 13 percent of Indias wind energy production. But Rajasthans Great Indian Thar Desert, the test site for Indias first underground explosion of a nuclear weapon 15 years ago, may now help make India a solar power as well. The desert set in Rajasthans largest district Jaisalmer, near the border with Pakistan, it is a place of sand dunes and shrub thickets – but also, increasingly, solar installations that could help change the character of Indias energy development. India committed at the U.N. Framework Convention on Climate Change negotiations in Copenhagen in 2009 to reduce its climate-changing emissions, per unit of GDP, by 20 to 25 percent by 2020, compared to 2005 levels. The country is currently the worlds seventh largest emitter of global warming pollution and the fifth biggest producer of emissions from burning fossil fuels. Sixty-eight percent of those emissions from fossil fuel use come from creating energy for the worlds second most populous country, according to Indias energy ministry. Today the country has 2.28 million megawatts of power generating capacity, and about 12.4 percent of that comes from renewable energy. Of the 2,632 megawatts of solar power now installed in India, Rajasthan so far has only 730 megawatts, putting it in second place behind the state of Gujarat, with 916 megawatts, according to Indias Ministry of New and Renewable Energy. But Rajasthan, Indias largest state and 60 percent covered by sunny desert, is now attracting the worlds interest as a solar hotspot. Around 1 lakh (100,000) square kilometers of barren land is available in the northwest arid belt of the state at cheaper rates that could be utilized for large scale solar projects. The government is formulating the policy to harness the enormous solar potential of the region to meet the countrys growing energy requirements. Besides large solar installations, the government is studying the possibility of grid-connected rooftop solar photovoltaic units for households. The Solar Energy Corporation of India estimates that 130 million homes could potentially be equipped with the units, creating 25,000 megawatts of generating capacity. said Alok, Rajasthans Energy Secretary.

Underutilized Fruits and Vegetables in Hot Arid Regions of India: Status and Prospects: A Review

The hot arid regions in India is spread in an area of 31.7 m ha, majority area being in Rajasthan (61%). The great Indian Thar desert is also located in this region. This region receives vary low rain fall with erratic distribution. Presence of harsh climatic condition such as high evapotranspiration, low relative humidity, with high aridity index and high wind velocity are other disadvantages. The soils are also light textured, less fertile, and prone to wind erosion. About 90 per cent of the area is dependent on monsoon rain for growing of annual crops which often fails due to insufficient rain or improper distribution. Despite these limitations, the region has good floral and faunal diversity that supports high human and livestock population. Many drought hardy perennial fruits and vegetables are grown with annual crops to complement farm income. Certain fruit crops like pomegranate (Punica granatum), Indian jujube (Ziziphus mauritiana Lam.), aonla (Emblica officinalis), date palm (Phoenix dactylifera) and Citrus species are grown commercially in irrigated areas. Many underutilized fruit crops also grow naturally or are cultivated. These include kair (Capparis decidua), lasora (Cordia myxa) jhar ber (Ziziphus nummularia), bordi (Ziziphus rotundifolia) pilu (Salvadora oleoides), khejri (Prosopis cineraria), phalsa (Grewia subinaequalis), Bengal quince (Aegle marmelos), karonda (Carissa carandas), prickly pear (Opuntia ficus-indica), kachri (Cucumis melo var. callosus) and snap melon (Cucumis melo var. momordica) etc. Most of these species are drought hardy with less incidence of pests and diseases yet give good yield despite environmental constraints. They serve as a source of nutrition for rural people being rich in vitamins, minerals, dietary fibres and other bioactive compounds. Germplasm collection, evaluation, conservation, ethnomedicinal values, improvement, propagation, agrotechniques, post-harvest management, value addition and future prospects of some of these crops are discussed in the paper.

Effect of Prosopis cineraria (L) druce pods and camel milk for nutritional enrichment in traditionally fermented minor millet's drink

Nations around the world are faced with various nutritional challenges in terms of malnutrition and unbalanced nutrition to maintain healthy lifestyles and longevity of their populations. The quest for innovative interventions in existing traditional food recipes hold promises to address local and regional nutritional issues. It includes amalgamation of traditional foods with locally available ingredients for nutritional efficacy and enrichment. Such an attempt has been made on a traditional food called ‘Rabadi’ from western arid and semi-arid regions of the Great Indian Thar Desert. It is prepared by fermentation of ‘Bajra’ – a pearl millet (Pennisetum glaucum) cereal with addition of country buttermilk derived from defatted buffalo or cow milk yogurt. Its intervention was replacement of the buttermilk with inoculated camel milk and incorporation of local ingredients as soybean and flour of ‘Khokha’ – the ripe fruit pods of ‘Khejri’ (Prosopis cineraria) tree. The results exhibited significant enhancement of bioavailable proteins, higher digestibilities and starch hydrolysis to improve glycemic response with overall good acceptability in sensory analysis. The comprehensive results demonstrate promising enrichment of nutrition and a fair capable solution for better health prospects in proposed intervention of the traditional food recipe.

A new record of gastroid fungus Broomeia congregata Berk. from Great Indian Thar Desert, India

Indian Thar desert mostly covering North–Western parts of Rajasthan is known for high temperature, high wind velocity, low rainfall and minimum relative humidity. The harsh climatic conditions of the region had wide fungal diversity along with several unreported species. Present study was aimed to explore the diversity of gastroid fungi from the Indian Thar desert. During survey a gastroid fungus was found growing in the rainy season under Prosopis juliflora tree. The fungal fruiting bodies were collected and identified based on microscopic examination, scanning electron microscopy (SEM) and ITS-5.8S rRNA gene sequences as gasteroid fungus Broomeia congregata Berk., belonging to family Broomeiaceae (Basidiomycota). The ITS-5.8S rRNA gene sequences of the fungus were compared with that of available sequences using BLAST programme and submitted to NCBI, USA. The nucleotide sequence was assigned GenBank accession number MK208821 which is now available in public domain. The morphological characterization and molecular identification validated B. congregata Berk. as a new record from great Indian Thar desert.

Biosynthetic Potential of Bioactive Streptomycetes Isolated From Arid Region of the Thar Desert, Rajasthan (India).

Acquisition of Actinobacteria, especially Streptomyces from previously underexplored habitats and the exploration of their biosynthetic potential have gained much attention in the rejuvenated antibiotics search programs. Herein, we isolated some Streptomyces strains, from an arid region of the Great Indian Thar Desert, which possess an ability to produce novel bioactive compounds. Twenty-one morphologically distinctive strains differing in their aerial and substrate mycelium were isolated by employing a stamping method. Among them, 12 strains were identified by a two-level antimicrobial screening method, exerting antimicrobial effects against a panel of indicator strains including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus species. Based on their potent antimicrobial activity, four isolates were further explored by 16S rRNA gene-based identification, genetic screening, and metabolomic analysis; and it was found that these strains belong to the genus Streptomyces. The selected strains were found to have polyketide synthase and non-ribosomal peptide synthetase systems. In addition, extracellular metabolomic screening revealed that the isolates produced analogs of doxorubicinol, pyrromycin, erythromycin, and 6-13 other putative novel metabolites. These results demonstrate the significance of Streptomyces inhabiting the arid region of Thar Desert, suggesting that similar arid environments can be considered as the reservoirs of novel Streptomyces strains that could have biotechnological significance.

Ecology and conservation of golden jackal (Canis aureus) in Jodhpur, Rajasthan

At north-west of India there is dry, semi arid region called as The Great Indian Thar desert. It lies between 24o and 35o 5’ N latitude and 70o 7’ and 76o 2’ E. Mammals of Thar desert includes the wolf (Canis lupus), the stripped hyaena (Hyaena hyaena), golden Jackal (Canis aureus), the Indian desert fox (Vulpes v. pusilla), wild bore (Susscrofaspc.), black buck (Antilo pecervicapra), blue bull (Boselaphus tragocamelus), chinkara (Gazella benneti), Hanuman langur (Semenopithecus entellus) etc. Golden Jackal is unique in distribution, occurrence, and survives at different environmental conditions in India including the hot desert. Present study has been carried out at Phitkasni village, situated south-east of Jodhpur city. Large population of golden Jackal has observed and data of their homerange, territory, inter-specific relation, conflict with human and mortality has been studied. It is concluded that regular monitoring and proper conservation management is needed in this area so Jackal and other carnivore like wolf, desert fox and hyena can also be conserved.

Source and transportation of summer dust over the Tibetan Plateau

Satellite observational evidences (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations, CALIPSO) have presented that the Tibetan Plateau (TP) is subject to heavy loading of dust aerosols during summer. Combining back trajectory and weather system analyses, the source and transportation of summer Tibetan dust from 2007 to 2014 were investigated. The Tibetan dust is mainly from the Taklimakan Desert and partially from the Gurbantunggut Desert and Great Indian Thar Desert. Case study indicates that the meteorological conditions together with the topography benefit the dust emission adjacent to the TP and the transport toward the plateau. When a cold advection or front developed by strong cold advection passes, dust particles are emitted into the atmosphere from the Taklimakan and Gurbantunggut deserts and then transported to the northern slope of the TP with northeasterly wind induced by the Altai and Tian Shan mountains. For the period from 2007 to 2014, the correlation coefficient of the monthly frequencies of summer dust events over the TP and cold advection passing the Taklimakan and Gurbantunggut deserts were as high as 0.68 and 0.34, respectively. Differently, although the correlation is limited, much TP dust mobilized from the Great Indian Thar Desert is associated with the passing low-pressure system activity and generally polluted by anthropogenic aerosols. The polluted dust is further transported to the southern slope of the TP by the prevailing westerly wind. Investigations on the source and transportation of summer dust over the TP provide a solid foundation of data that can be used to reveal the role of TP dust in the radiation balance, hydrological cycle, and monsoon cycle in India and East Asia.

Culturable bioactive actinomycetes from the Great Indian Thar Desert

The present study was attempted to determine the antimicrobial potential of actinomycetes from the Great Indian Thar Desert. A total of 100 different morphotypes based on phenotypic characterization were isolated from desert ecosystems located in the northwest of India and tested for their antimicrobial activity by the cross-streak method. Among the strains tested, 13 actinomycetes exhibiting strong antimicrobial activities against several test organisms, including multidrug resistant bacteria (MRSA) were chosen for a phylogenetic diversity study. The results of 16S rRNA gene sequencing showed their affiliation to actinobacterial genera: Actinomadura, Nocardia, Nonomuraea, Spirillispora, and Streptomyces. Three of these isolates were considered to be new members of the Streptomyces genus and another strain also seemed to be a new species of the genus Spirillispora. Among these strains, five were chosen to study the bioactive products using Q-Tof-MS because of their broad spectrum activity against the panel of test pathogens used. The results showed that they produce many known compounds and might produce few unknown compounds as well. This is the first such report on the selective isolation of actinomycetes from the Great Indian Thar desert, and their screening for antibacterial potential. This ecosystem has never before been explored to this extent.

Sources and processes governing rainwater chemistry in New Delhi, India

Rainwater plays an important role in scavenging of aerosols and gases from atmosphere, and its chemistry helps to understand the relative contributions of atmospheric pollution sources. The present work is aimed to understand and explain the sources, seasonal patterns and the processes thereof affecting rainwater chemistry in an urban environment of Delhi, India. Rainwater samples (n = 111) collected throughout the year in New Delhi showed alkalinity in general. Eight rainwater samples, collected in late monsoon and winter season, had pH less than 5.6 indicating that Delhi continues to face the prospects of acid rain despite the introduction of compressed natural gas as the clean fuel in city transport. Organic acids could be the possible contributors of acidity in rainwater samples having the fractional acidity (FA) value of 0.174, which is greater than the annual average FA (0.011) and the (Ca2+ + Mg2+ + NH4 +)/(SO4 2− + NO3 −) ration of more than one. Average acid neutralization factors of cations decrease in the order Ca2+ (1.01) > NH4 + (0.77) > Mg2+ (0.10). However, neutralization by Ca2+ dominates only in summer season as cation-rich dust is transported from the Great Indian Thar Desert to this region by strong summer S–SW winds, while NH4 + dominates in rainwater of other three sampling seasons. Identified dominant sources for soluble ions in rainwater are (1) non-silicate crustal source for carbonates and sulfates of Ca and Mg, (2) emissions from catalytic convertor-fitted vehicles and agriculture fields for NH3 and (3) mixed anthropogenic sources for SO4 2−, NO3 − and Cl−. Rainwater chemistry showed significant seasonal variations. This could be due to the changes in relative proportions of natural and anthropogenic sources of soluble ions to rainwater. Dominance of anthropogenic sources over crustal sources can result in acidic rains, which can adversely affect the environment and human health in this region.

Characterization of aeolian sands from Indian desert

Aeolian sands, from Sam, Jaisalmer, Rajasthan, India, belong to the Great Indian Thar desert and, primarily, attract tourists from India and all over the world. Though, certain studies were conducted on the geological origin of these sand and deserts, results related to their physical, chemical, morphological, mineralogical, thermal, electrical and geotechnical characteristics are scanty. However, with an increase in demand of the land for infrastructure development (for residential, commercial and strategic facilities), for which their stabilization may be essential, and a need to utilize these (aeolian) sands as a construction material, particularly due to acute scarcity of sand, their complete characterization becomes essential. With this in view, a detailed study was conducted to characterize these sands and details are presented in this paper. In general, these sands are found to exhibit properties similar to aeolian sands from the Arabian Peninsula, Australia and China. Further, with an intention to utilize these sands in construction industry, especially as fine aggregate in concrete and mortar and designing thermal beds for buried conduits and electrical cables, the results have been compared with those for the Indian standard sands. Based on the chemical composition and chemical properties, and crushing strength of aeolian sands, their utilization in concrete and other construction materials (viz., bricks, building blocks, paver blocks etc.) appears to be quite promising. Also, the collapse potential of these sands has been found to be quite low while its angle of internal friction is quite high. These parameters suggest that aeolian sands from the Great Indian Thar desert can also be used for various engineering applications.

The Composition of Essential Oil from Cymbopogon Species of the Great Indian Thar Desert

The Composition of Essential Oil from Cymbopogon Species of the Great Indian Thar Desert

Physico-chemical properties and petrographic characteristics of the Kapurdi lignite deposit, Barmer Basin, Rajasthan, India

The Kapurdi lignite deposit of the Barmer Basin is one of the important Tertiary lignite deposits underlying the Great Indian Thar desert in the northwestern part of Rajasthan. The sedimentary sequence of the area is characterised by marked lithofacies changes over short distances. The lignite beds in the sequence are lenticular in shape, dark brown and exhibit non-banded granular texture. The Vicker's micro-hardness values ( HμV) vary in close range from 20.0 to 22.0 kg/mm 2. Chemical analysis of the lignites has shown that they are low in ash and matured in rank, like the lignite deposits of the Palana Basin. The lignite ash contains low silica contents with appreciable quantities of alkali and other oxides. This has caused the lower ash fusion temperatures. Petrographic studies have revealed that the huminite group of macerals is the dominant constituent in all the samples. Humocollinite is the major constituent in the lignite beds, while humodetrinite predominates in the carbonaceous beds. In the liptinite group, resinite is the major component. It is found as infillings of cavities, joints and cell lumens. Conspicuously, the inertinite (organic inert) content is very low and is mainly represented by fungal bodies of sclerotinite. The reflectance values of Kapurdi lignites further corroborate that they are matured in rank and may be grouped in the “hard brown coal” category.

Population of goats related to climate in western India: an ecological assessment

Western India experiences arid to dry subhumid ecoclimate. Aridity increases from east to west to the Great Indian Desert or Thar Desert. The desert economy is animal based and goats are the most common livestock; density of goats increases with increase in aridity. There are large morphological variations in goats warranting the recognition of population differences throughout the region. The present investigations were therefore undertaken to see whether there are population differences and, if so, to establish the populations on a sound ecological basis. Eleven physical measurements of the animals were made in the fields of western India in a total of 518 animals (255 adults). Five populations were initially segregated by means of a scatter diagram. Population differences were confirmed by mathematical treatments using analysis of variance (one-way and two-way) and Students-Newman-Keuls test, which yields a critical comparison among means. Discriminant analysis was used to determine whether the goat populations differed significantly between the five climo-edaphic-vegetational zones. Each population was designated according to the locality having the greatest density as: POP1Ku, POP2Sa, POP3Jh, POP4Ga, POP5Pa. The five populations occurring in distinct climo-edaphic-vegetational zones or ecological niches in western India may be referred to as ecotypes.