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The remote villages in arid and semi-arid inland regions of Rajasthan state in India and many other countries are dependent on brackish groundwater for potable uses. Generally, community RO (Reverse Osmosis) plants are installed for brackish water treatment in rural agglomerations where the MLD (Minimal liquid discharge) scheme is followed which includes pre-treatment and pre-concentration technologies, that consumes relatively low energy than thermal technologies for ZLD (Zero liquid discharge). This paper discusses the application of hybrid processes involving MLD technologies such as IEX (Ion Exchange), NF (Nanofiltration), RO, FO (Forward Osmosis) and UF (Ultrafiltration). for brackish water treatment. The impact of feed water quality and operational parameters such as flux, feed flow rate and transmembrane pressure are discussed. Further, performance indicators such as salt rejection, recovery, energy consumption and scaling propensity are discussed to evaluate the feasibility of various configurations. The findings of this review indicate NF as impressive membrane technology for conjunction with IEX, RO and UF. Further, the use of FO or NF as a pre-treatment for RO has been found to reduce the scaling propensity of RO membranes; and the use of UF as a pre-treatment for NF has been found to reduce the propensity of organic fouling on NF membranes. Also, IEX as a pre-treatment can be coupled with low-pressure RO/NF to remove the scale-causing divalent ions and enhance recovery along with an option of reusing RO/NF reject water for regeneration of IEX column. [ABSTRACT FROM AUTHOR]

The paper contributes to the growing literature highlighting the significance of assessing risk and vulnerability, micro-level perceptions and adaptation decision-making in building resilience of farm communities to climate change in dryland region of India. To select a region for grassroots enquiry, spatial differential in risk to climate change was assessed in Rajasthan, using IPCC AR5 framework. Among the highly vulnerable and risky districts, Bikaner district was selected for elicitation of micro-level imperatives. Rising atmospheric temperature, inter-seasonal displacements of rainfall and recurrence of extreme events were perceived by the farmers resulting in resource degradation, production risks and erosion of households' socio-economic dynamics. As risk preventive measures, suitable adjustment in agricultural practices, natural resource management, shift to off-farm activities and other relief measures were adopted by the farmers. Farmer's choice of adaptation was influenced by several climatic, socio-economic and infrastructural & institutional factors in varying degree. Moreover, several financial, economic, infrastructural and informational bottlenecks to adaptations were reported during household survey and FGDs. The results suggest that capturing grassroots evidence is crucial for directing locally tailored adaptation strategies, along with the improving deficiencies in the developmental pathways for climate-resilient agriculture. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The present paper reports the rediscovery of Helicobarbula porphyreoneura (Müll. Hal.) M.J. Cano in and around Jaigarh fort of Jaipur, Rajasthan (India). The article not only reports in detail the delimitation of Pseudocrossidium and the segregated genus Helicobarbula, where P. porphyreoneurum is currently placed but also provides a detailed description of the species along with illustrations that have not been published yet. Besides this, the current status of the distribution of Helicobarbula and Pseudocrossidium in India is also discussed. [ABSTRACT FROM AUTHOR]

The role of groundwater in irrigation and drinking purposes and sustaining growth in economy is well-known. Groundwater is generally less susceptible to contamination and pollution when compared to surface water bodies. This paper is based on extensive investigations on the spatial and seasonal representative measurement of chemical parameters from 80 dug wells of Churu and adjoining Bikaner districts of Rajasthan, India. The region has dearth of water resources — both surface and sub-surface, with the main source of water being the dug wells. The application of hydro-statistical techniques and tools like Pearson's correlation coefficient, relative activity of sodium ion (SAR), Wilcox diagram, Piper diagram and magnesium hazard indicate that the chemical parameters of the water of the study region is of very poor quality and not suitable for drinking and irrigation purposes. Wilcox diagram shows high sodium content, can destroy the soil structure rendering the soil and water unsuitable. [ABSTRACT FROM AUTHOR]

As the spectre of climate change gains in strength with each passing moment, many of our mundane food crops like rice face the heat, leading to uncertain yields and unforeseen disease outbreaks. Subsequently, mankind is forced to look for alternative food choices that should primarily come from indigenous plants that are less demanding in terms of usage of water and application of chemical-based fertilizers/pesticides. There are plants growing in the wild in the arid and semi-arid zones of Rajasthan, India, that can come to the rescue, with an added potential for development into valuable functional foods—i.e., not only as source of carbohydrates, proteins, and micro-nutrients but also that of health benefiting nutraceuticals (like antioxidant flavonoids) and relevant enzymes. The other parts (non-edible) of these plants have often also been traditionally validated via diverse ethnomedicinal practices; these could also be useful bioenergy sources. Keeping in mind the broader aim of looking at future functional foods that are also required to be environmentally sustainable, the current report: (a) reviews the extant literature on underutilized legumes from arid/semi-arid zones, (b) discusses current status with respect to biological activities present therein, and (c) suggests pertinent research questions and solution paths in the domains of bioactives, bioenergy, and sustainable environment. [ABSTRACT FROM AUTHOR]

The present form of Urbanisation Pattern in India cannot sustain the water requirements in cities, especially in semi-arid regions of India. The tacit knowledge of water resilience has been used since time immemorial to tap and address water demand and risk in India. Now is the right time to blend the traditional and modern technology to address water issues for water resilience. This paper explores the traditional knowledge and its usage in water management system in semi-arid areas and how water resilience can be achieved through co-production of water at a local level in Jodhpur City in the state of Rajasthan. It explores how the water system has been losing its value due to degradation caused by the spatial expansion of the city. It analyses water stress both in terms of water scarcity as well as managing the excess. Using primary and secondary data gathered, the paper proposes ways of co-production of water with community for sustainability and resilience. It suggests eco-restoration of traditional water system, importance of inclusion of varied actors, etc in addition to addressing SDG 6, and using ISO/BIS standards for water resilience. • Water stress to be a critical aspect for sustainability of cities in India. • Importance of integration of tacit/traditional knowledge with explicit knowledge. • Co-production of water for addressing issues related to water resilience. • ISO/BIS standards as a tool for assessing performance on water resilience. [ABSTRACT FROM AUTHOR]

The commonly used precipitation-based drought indices typically rely on probability distribution functions that can be suitable when the data exhibit minimal discrepancies. However, in arid and semi-arid regions, the precipitation data often display significant discrepancies due to highly irregular rainfall patterns. Consequently, imposing any probability distributions on the data for drought analysis in such regions may not be effective. To address this issue, this study employs a novel drought index called the Discrepancy Precipitation Index (DPI), specifically designed for arid regions. Unlike traditional methods, the DPI does not impose a probability distribution on the precipitation data; instead, it relies on the discrepancy between the data and the mean value. Drought severity classifications (i.e., Drought-I, Drought-II, and Drought-III) are proposed based on the DPI values. The DPI is used to characterize and assess the meteorological drought years based on annual and monsoonal precipitation over nineteen districts in Western Rajasthan, India, during 1901–2019. Additionally, a novel statistic called Discrepancy Measure (DM) is employed to assess the degree of discrepancy in the precipitation climatology of the districts for annual and monsoon precipitation time series. Based on annual precipitation, Jaisalmer district exhibited the highest number of historical drought years (35), whereas three districts, i.e., Jhunjhunu, Dausa, and Bhilwara exhibited the lowest number of drought years (11). Similarly, based on monsoon precipitation, Jaisalmer and Bhilwara encountered the highest (34) and the lowest (11) number of drought years, respectively. The return period of Drought-II is lower for monsoon precipitation-based DPI as compared to that of the annual precipitation-based DPI for all the districts. The DM and DPI-based total number of droughts are found to be strongly correlated for both annual and monsoon precipitation. The DM value is highest for Jaisalmer and lowest for Bhilwara district. The findings reveal DPI as an efficient tool for assessing drought years, particularly in arid climatic conditions. Moreover, as the DM value increases for a precipitation series, the DPI becomes more effective in capturing drought events. [ABSTRACT FROM AUTHOR]

Background: Clusterbean is an important legume crop in arid and semi-arid regions of Rajasthan. It provides livelihood security to arid zone farmers. Bacterial leaf blight (BLB) and root rot are two important diseases of clusterbean which limits its production and productivity. Although, management of these diseases are possible through fungicides. However, in present study focus on use of bio agents which are friendly to the environment. Methods: Field experiment was conducted at ARS, SKRAU, Bikaner, Rajasthan during three consecutive kharif seasons of 2017 to 2019. The experiment was conducted on cv. RGC-1033 with six different combination of Trichoderma harzianum and Pseudomonas fluorescens bio-agents viz, seed treatment, soil treatment and their combinations against the root rot disease and compared with an untreated control. Conclusion: Seed treatment with a combination of T. harzianum + P. fluorescens (4+4 g/kg seed) along with soil application of T. harzianum + P. fluorescens (1.25 +1.25 kg in 50 kg FYM for each/ha) was an effective treatment which reduced root rot incidence and increased seed yield under field conditions. It can be recommended to the cultivators of clusterbean for enhancing yield. [ABSTRACT FROM AUTHOR]

A checklist, distribution pattern and taxonomic keys to the Carabidae fauna of the Thar Desert (Rajasthan) are provided. Seventeen species belonging to five subfamilies (Anthiinae, Brachininae, Carabinae, Harpalinae, and Licininae) were recorded. Eight species of Carabidae are first records from the state of Rajasthan. [ABSTRACT FROM AUTHOR]

This study encompasses the grain size distribution of the playa lakes (Pachpadra, Pokhran, and Didwana) of the Thar Desert in Rajasthan, India. The grain size of sediment particles is the most fundamental feature, giving essential information regarding their origin, transport history, and depositional conditions. The aeolian and fluvial transport processes were evaluated through environmentally sensitive grain size subpopulations to identify the differential sedimentary sources and dynamics in the playas. End-member modelling further determined the sediment grain size distribution through statistical analysis. The playa sediments mainly consist of very fine sand (46–54%) and very coarse silt (22–37%). The results show that the average fine fraction of Pachpadra, Pokhran, and Didwana playa was 46.29%, 66.11%, and 66.28%, respectively. In contrast, the average coarser fraction deposition in Pachpadra, Pokhran, and Didwana corresponds to 53.71%, 33.89%, and 33.72%, respectively. This suggests that the playas mostly contain aeolian sediment rather than fluvial sediment transported by dust/sand storms. Additionally, the textural pattern and depositional distribution of the sediments determined through the Passega CM diagram and bivariate plots indicate that 82% of the samples were poorly sorted, and 18% were very poorly sorted. Furthermore, an environmentally sensitive grain size component (ESGSC) was also assessed to identify the spatial variability and transport processes of sediment between these playas. Three ESGSCs in Pokhran (250 µ, 31 µ, and 2 µ) and Pachpadra (125 µ, 31 µ, and 4 µ), while two ESGSCs in Didwana playa (125 µ and 16 µ) were identified, indicating sediment deposition with moderate velocity in a low energy environment with a mixed sediment population transported by aeolian and fluvial activities. [ABSTRACT FROM AUTHOR]

The arid region of Rajasthan has been classified into unique agro-ecological sub-regions, zones, and sub-zones (indicated by their code number in this abstract) for which sustainable land use has been suggested based on the potentials and constraints. 2.1, 2.2 and 3.1 sub-zones need dune stabilization, silvopastural farming, and kharif cultivation in interdunes; khadin water harvesting system, as well as solar farming. 4.1 and 4.2 sub-zones need rainfed cropping under conserved moisture, agroforestry and limited irrigation, cultivation of low water requiring crops, such as mustard, cumin in rabi. In 4.3 sub-zone under conserved moisture and winter rainfall pulses and mustard are suggested. In 5.1 and 5.2 sub-zones kharif season crops and wheat, mustard, cumin, and condiments irrigated with brackish groundwater by adopting gypsum treatment are suggested. In the canal command area, the micro-irrigation system is doing well in the sandy plain and dune complex area, but in the Ned area irrigation needs to be restricted/avoided. In 5.3 and 5.4 sub-zones, rainfed irrigated crops and fruit cultivation is suggested. In 6.1 sub-zone dune stabilization is suggested; 6.2 and 6.3 sub-zones require erosion control and irrigation water management for the cultivation of cotton, paddy, groundnut, sugarcane, and kinnow. [ABSTRACT FROM AUTHOR]

Climate change is a major concern in Rajasthan's water-stressed state. Climate change has a direct impact on the water resources in many parts of the state. In comparison to the rest of the country, the state has a larger portion of desert or arid lands (58% of the total geographical area) and limited water resources. Therefore, any adverse climate change conditions will likely have a catastrophic impact on the state's already vulnerable water resource system. Attempts have been made in this study to understand the state's climate conditions and highlight isolated past events that suggest climate change may occur in the state. It is emphasised that climate change modelling for various types of climate is required. To develop optimal water resource management strategies for different zones, cutting-edge tools such as remote sensing and geospatial tools must be used. The study's overarching goal is to comprehend the impact of climate change on the study area's water resources. The study's objectives are as follows: (1) to determine the effects of climate change on the water resources of the study location, (2) to investigate the nature and impact of climate change-induced drought disasters in the study area, (3) to identify methods and strategies for mitigating potential risks and vulnerabilities due to climatic variations and (4) determine the scope of research and policy action in response to identified current and future vulnerabilities, as well as the anticipated effects of climate change. The descriptive study used both quantitative and qualitative data collection methods. A total of 100 respondents were chosen from the villages of Rajasthan's Tonk district for quantitative data collection and 05 in-depth interviews with various stakeholders were conducted for qualitative analysis. The study revealed that indigenous knowledge systems have allowed various communities in the area to live in harmony with their environments for generations and that their traditional knowledge systems are essential tools in environment conservation and natural disaster management. Again, according to the study, the majority of respondents believe that climate change is a cause of drought disasters, which should be addressed through effective participatory research. The qualitative interviews made known themes such as stakeholder participation, climate modelling, the impacts of climate change on key development sectors, adaptation needs, initiatives, opportunities, and so on. The findings imply that climate change is one of the critical reasons for the occurrence of drought disasters in the study area and the state as a whole; drought and climate change have severely impacted water resources. To conclude, the study emphasises the emerging need for research, policy, and action to mitigate the impact of climate change on water resources and related areas. [ABSTRACT FROM AUTHOR]

Drought is a dominant climatic feature in arid and semiarid regions. Climate change, temperature variability, and anthropogenic activities caused an increase in agricultural droughts in many regions. Investigation of drought dynamics is important for innovative planning and management of natural resources in drought-prone areas. Remote sensing indices and earth observational datasets were used in this study to investigate droughts in the Bikaner city of Rajasthan, India. Vegetation condition index (VCI), temperature condition index (TCI), and vegetation health index (VHI), estimated from multitemporal Landsat datasets, were used for monitoring the drought-prone areas. Land use land cover (LULC) map, normalized difference vegetation index (NDVI), and surface temperature were also calculated for monitoring the decadal changes in surface features. The results showed that barren lands decreased from around 162.75 to 79.59 km2. The annual average temperature increased by 0.72 °C, while agricultural land increased by 33.83 km2 during 1990‒2020. There was a gradual increase in droughts, but the increase was more in recent years than in the early period. The climatic condition revealed from VCI, TCI, and NDVI maps indicated most of the Bikaner city is prone to moderate and extreme droughts. The study indicates the need for VCI-based real-time drought monitoring for drought management. [ABSTRACT FROM AUTHOR]

Water quality degradation and metal contamination in groundwater are serious concerns in an arid region with scanty water resources. This study aimed at evaluating the source of uranium (U) and potential health risk assessment in groundwater of the arid region of western Rajasthan and northern Gujarat. The probable source of vanadium (V) and fluorine (F) was also identified. U and trace metal concentration, along with physicochemical characteristics were determined for 265 groundwater samples collected from groundwater of duricrusts and palaeochannels of western Rajasthan and northern Gujarat. The U concentration ranged between 0.6 and 260 μg L−1 with a mean value of 24 μg L−1, and 30% of samples surpassed the World Health Organization's limit for U (30 μg L−1). Speciation results suggested that dissolution of primary U mineral, carnotite [K2(UO2)2(VO4)2·3H2O] governs the enrichment. Water–rock interaction and evaporation are found the major hydrogeochemical processes controlling U mineralization. Groundwater zones having high U concentrations are characterized by Na–Cl hydrogeochemical facies and high total dissolved solids. It is inferred from geochemical modelling and principal component analysis that silicate weathering, bicarbonate complexation, carnotite dissolution, and ion exchange are principal factors controlling major solute ion chemistry. The annual ingestion doses of U for all the age groups are found to be safe and below the permissible limit in all samples. The health risk assessment with trace elements manifested high carcinogenic risks for children. [ABSTRACT FROM AUTHOR]

Background: Dry root rot of chickpea caused by Macrophomina phaseolina (Tassi) Goid. is emerging as a serious threat to the chickpea production worldwide. The disease is gaining importance under the changing scenario of climate particularly in the rainfed ecologies of India and in arid and semi-arid region of Rajasthan. The current study was aimed to discusses current status of the disease and role of different factors in disease development to help in searching of possible management options for researchers to alleviate the problem. Methods: A roving survey was conducted to record the occurrence and distribution of dry root rot in ten major chickpea growing districts of Rajasthan during rabi season 2014-15 and 2015-16. In each district, minimum three locations/villages were selected, in each location/village minimum three fields were selected and the incidence of disease was recorded after counting the diseased and healthy plants. Result: Overall range of disease incidence in all the districts vary from 5.75 to 12.51 per cent with an average of 9.15 per cent in Rajasthan. The maximum disease incidence 12.51 per cent was observed in Jaisalmer district while minimum in Ajmer district. The disease was found very common in sandy and sandy loam soil than any other types of soil. The deshi/local varieties were found to be more susceptible to infection of M. phaseolina as compared to improved varieties. Disease incidence was also observed higher in sprinkler system of irrigation as compared to flood method and rainfed conditions. The maximum disease incidence was observed in plants at flowering and podding stages in the months of February and March. [ABSTRACT FROM AUTHOR]

Background: Groundnut is an important kharif crop in Rajasthan and occupies important position among state crop list. However, a vast yield gap exists between potential yield and the actual yield obtained due to partial adoption of recommended package of practices by the farmers. The technology gap is a major concern in achieving optimum and sustained production. Considering the facts, present study aimed to study the effect of adaptation of improved technologies in groundnut production, water productivity and sustainability in arid zone of Rajasthan. Methods: Field experiment of groundnut was carried out during four consecutive years 2016 to 2019 on farmer's field of Bikaner districts under cluster frontline demonstrations to assess the impact of improved technologies on yield sustainability, water productivity and economics of groundnut crop. The two treatments evaluated at 25 farmer's field were a) improved technologies i.e. high yielding varieties, seed treatment, timely sowing, optimum plant population, recommended fertilizer management, plant protection measures and irrigation management and b) farmers practice. The groundnut yield, water productivity, sustainability indices, economic returns and benefit to cost ratio of both the systems was compared using appropriate standard statistical procedure. Result: The results of the present field experiment revealed that, the improved practices gave higher and sustainable yield of groundnut over years compared to farmers practice. The mean pod yield recorded (3371 kg ha-1) with improved practices was 24.39 per cent higher than farmer's practice (2710 kg ha-1). Similarly, improved practices had higher sustainability yield index (0.63), sustainability value index (0.47), higher water expense efficiency (74.92 kg ha-1 cm-1), gross water productivity (16.58 m-3), net water productivity (11.89 m-3) and incremental benefit cost ratio (30.1) over farmers practice. [ABSTRACT FROM AUTHOR]

Plant growth‐promoting bacteria (PGPB) expressing 1‐aminocyclopropane‐1‐carboxylic acid (ACC) deaminase activity are widely acknowledged to have a role in mitigation of abiotic stress caused by extreme environmental conditions. Consequently, several studies have focused on the isolation of ACC deaminase positive PGPBs. However, the application of such strains in drought‐prone arid regions has remained grossly under‐exploited. In order to be used in arid agroecosystems, PGPBs need to have the dual capability: to express ACC deaminase and to have the ability to tolerate increased temperature and salt concentration. Conspicuously, to date, very few studies have reported about isolation and characterization of PGPBs with this kind of dual capability. Here we report the isolation of bacterial strains from rhizosphere(s) of Cyamopsis tetragonoloba, a commercial crop from arid regions of Rajasthan, India, and their characterization for ACC deaminase activity and thermohalotolerance. Isolates found positive for desired traits were subsequently assessed for plant growth promotion under simulated drought conditions. Our finding showed that although the bacterial diversity within the rhizosphere of C. tetragonoloba grown in the arid region is quite poor, multiple isolates are ACC deaminase positive. Four isolates were found to be ACC deaminase positive, thermohalotolerant, and successfully enhanced drought tolerance. These isolates were identified as strains belonging to genera Pseudomonas, Enterobacter, and Stenotrophomonas based on 16S rRNA sequence homology. [ABSTRACT FROM AUTHOR]

Simple Summary: We present a systematic investigation of the distribution of microbial communities in arid and semi-arid regions of Thar Desert Rajasthan, India. Their responses in multiple environmental stresses, including surface soil, surface water and underground water were evaluated. We further assess the biotechnological potential of native microorganisms and discover functional species with results providing a detailed understanding of the abundance of microbial communities in these regions, associated with various stress-related biogeochemical and biotechnological processes. We hope our work will facilitate the development of effective future strategies for the use of extremophiles in complex environments. The arid and semi-arid regions of Rajasthan are one of the most extreme biomes of India, possessing diverse microbial communities that exhibit immense biotechnological potential for industries. Herein, we sampled study sites from arid and semi-arid regions of Thar Desert, Rajasthan, India and subjected them to chemical, physical and metagenomics analysis. The microbial diversity was studied using V3–V4 amplicon sequencing of 16S rRNA gene by Illumina MiSeq. Our metagenomic analyses revealed that the sampled sites consist mainly of Proteobacteria (19–31%) followed by unclassified bacteria (5–21%), Actinobacteria (3–25%), Planctomycetes (5–13%), Chloroflexi (2–14%), Bacteroidetes (3–12%), Firmicutes (3–7%), Acidobacteria (1–4%) and Patescibacteria (1–4%). We have found Proteobacteria in abundance which is associated with a range of activities involved in biogeochemical cycles such as carbon, nitrogen, and sulphur. Our study is perhaps the first of its kind to explore soil bacteria from arid and semi-arid regions of Rajasthan, India. We believe that the new microbial candidates found can be further explored for various industrial and biotechnological applications. [ABSTRACT FROM AUTHOR]

Abstract: Community forests/rangelands, called Orans and Gauchars in the western arid part of India, constitute a significant proportion of the total geographical area of the region. Given the economic importance of these areas from time immemorial, the local people took special care to protect and sustainably utilize these common property resources. However, these forests and rangelands have suffered severe degradation in the recent past. Rehabilitation of Orans and Gauchars needs proper planning and execution of a technically feasible package, tailored to suit their unique edaphic, climatic, vegetation, social and legal status. Keeping in view the vast potential of these areas to sustain large scale livestock farming for overall economic upliftment of the local population, there is an urgent need to rehabilitate these degraded areas in an efficient and cost-effective manner. Salient problems faced by these natural assets of western Rajasthan and strategies for their rehabilitation have been discussed in the paper. [ABSTRACT FROM AUTHOR]

In arid and semiarid regions, groundwater is required for the drinking, agriculture, and industrial activities due to scarcity of surface water. Groundwater contaminated with high concentrations of fluoride and nitrate can severely affect human health in these regions. Twenty-eight groundwater samples from rural habitations of Jhunjhunu district, Rajasthan, India, were collected in March 2018 and subjected to analysis for water quality parameters. Fluoride and nitrate concentrations in groundwater varied from 0 to 5.74 mg/L and 10.22–519.64 mg/L, respectively. Nitrate content of about 86% samples and fluoride content of about 54% exceeded the permissible limit of Bureau of Indian Standards (IS:10,500) as well as World Health Organization standards. All groundwater samples belonged to poor to unfit drinking water quality index. Principle component analysis elucidates the anthropogenic contribution to high nitrate concentrations observed in this area. Noncarcinogenic human health risk evaluated from high nitrate and fluoride in drinking water for children, men, and women points to the fact that noncarcinogenic risk is exceeding the allowable limit to human health. The predominating hydrochemical facies in the area is Na+–HCO3−–Cl− followed by Na+–Mg2+–HCO3−–Cl−. The Gibbs plot and bivariate ionic cross-plots suggest the noncarbonate weathering (rock dominance), evaporation dominance, and ion exchange process to be the predominating geochemical mechanisms governing the evolution of groundwater hydrogeochemistry. Giggenbach diagram shows the immature character, i.e., incomplete equilibration of the groundwater. [ABSTRACT FROM AUTHOR]

Khetri Copper Belt, Rajasthan, is anthropogenically active and geologically belongs to the Delhi super-group. A study was designed to understand the geochemical processes controlling the elemental mobility in the groundwater. Sampling sites were divided into three zones, i.e. copper, quartzite and granite mine zones depending on the type of mineral excavated. A total of 32 representative groundwater samples were collected and analysed for heavy metals and radionuclide (U) using ICP–MS. A maximum U concentration (average 87 µgL−1) is observed in the quartzite mine zone, and minimum (average 13 µgL−1) is found in the copper mine zone samples. A high concentration of U (maximum of 430 µgL−1) in groundwater is attributed to mineral dissolution due to geogenic and anthropogenic activities. Despite the presence of Jaspura and Gothra granitoid in the copper mine zone, the abundance of U is low suggesting the scavenging of U by sulphides or iron oxides. Additionally, at the confluence of two geological groups, Fe concentration is found high with a low concentration of U which further confirms scavenging of U. It is evident from the results that in the absence of iron-bearing sulphides, U concentration in groundwater would be very high compared to the current concentration. It also indicates low concentration of U in the copper mine zone is due to dissolution of Fe sulphide-rich waste. The present study recommends further research to understand the feasibility of mining waste for the removal of U contamination from groundwater. [ABSTRACT FROM AUTHOR]

An increased nitrate (NO3−) concentration in groundwater has been a rising issue on a global scale in recent years. Different consumption mechanisms clearly illustrate the adverse effects on human health. The goal of this present study is to assess the natural and anthropogenic NO3− concentrations in groundwater in a semi arid area of Rajasthan and its related risks to human health in the different groups of ages such as children, males, and females. We have found that most of the samples (n = 90) were influenced by anthropogenic activities. The background level of NO3− had been estimated as 7.2 mg/L using a probabilistic approach. About 93% of nitrate samples exceeded the background limit, while 28% of the samples were beyond the permissible limit of 45 mg/L as per the BIS limits. The results show that the oral exposure of nitrate was very high as compare to dermal contact. With regard to the non-carcinogenic health risk, the total Hazard Index (HITotal) values of groundwater nitrate were an average of 0.895 for males, 1.058 for females, and 1.214 for children. The nitrate health risk assessment shows that about 38%, 46%, and 49% of the samples constitute the non-carcinogenic health risk to males, females, and children, respectively. Children were found to be more prone to health risks due to the potential exposure to groundwater nitrate. [ABSTRACT FROM AUTHOR]

Trends in reference evapotranspiration (ETo) estimated using Penman-Monteith equation were analysed over arid, semi-arid and humid regions of northwest (NW) India during 1985-2018. The Mann-Kendall is used to determine significance of trends. Theil-Sen's estimator and least square linear fitting methods are adopted to find slopes of the trend lines. The results indicated a significant decrease in ETo on annual basis for most of the locations and NW India as a whole. However, the trend was not statistically significant for seasonal ETo. The significant decrease in solar radiation and wind speed nullified the impact of increased temperature and resulted in slight decrease in ETo over arid and semi-arid regions of NW India which could probably be attributed to the increased dust hazy conditions prevailing. In NW India, water is a limiting resource the decrease in ETo may help researchers in decision makers to develop water assets and utilize the irrigation systems more effectively. There was also an increasing trend in production of major crops in the study region. Further, in near future, if this decreasing ETo trend were to remain, it would help in intensification of cropping system with the existing water resource. [ABSTRACT FROM AUTHOR]

The mustard production and productivity of the hot arid region of Rajasthan is dominated by both genetic makeup and environmental conditions. An experiment was conducted with four mustard varieties (RGN-73, RGN-229, RH-30 and Pusa bold) in two growing environments (open environment and neem shade). Pusa bold gave significantly higher plant height than other varieties. Among varieties, RGN-73 had significantly higher number of branches per plant, dry matter accumulation per plant, siliquae per plant, seed yield, stover yield, biological yield, harvest index and heat use efficiency than other varieties. However, significantly higher test weight was in Pusa bold variety. Under open environment condition, significantly higher growth, yield attributes, yield, harvest index and heat use efficiency were found as compared to neem shade environment. The results revealed that variety RGN-229 took more days for completion of life cycle as compared to other varieties, hence RGN-229 variety required significantly more degree days than other varieties. The pheno-thermal index was significantly higher in open condition. [ABSTRACT FROM AUTHOR]

Land use land cover (LULC) classification of Churu district of Rajasthan state in India was done through hybrid classification technique. Landsat imageries of 1998, 2008 and 2018 were used to ascertain the rate and nature of spatio-temporal LULC changes. Major focus was given on vegetative cover change detection of the study area. On the basis of field survey and standard classification classes, the land use classes of the study area were divided into eleven classes. A detailed vegetative classification has been done while categorizing the classes. This classification method employed maximum likelihood and ISODATA clustering. The decision tree approach was used to create the multi-temporal hybrid LULC classification. The accuracy assessment results have shown excellent results at 91% overall accuracy with a kappa of 0.92. The results indicated that agriculture, crop land dominated the land use of Churu district while natural vegetation (forest areas) had the least share in land cover during the entire study period from 1998 to 2018. Shannon's entropy index was used to determine the changes in spatial distributional pattern of built up during the period 1998 to 2018 for the study area in general and also for each of the eight sub-administrative regions (tehsils). The increase in the built up area in the study area during the period of 1998 to 2018 was quite paltry with a general dispersed type of built up. The increase varied from moderate to nominal with the entropy value decreasing from 0.84 to 0.71 for the study area in general. [ABSTRACT FROM AUTHOR]

1. The aim of this study was to determine the nutritional status of backyard chickens reared under 4 different agro-climatic conditions (tropical, humid subtropical, cool-temperate and semi-arid) of India during different seasons of the year and to compare their nutritional status with those reared under confined feeding system (CFS). In each season, 15 adult and 15 grower chickens were slaughtered for collecting content of crop and gizzard to assess the nutritional status from different agro-climatic conditions. 2. The dry matter content of crop and gizzard was higher (P < 0.01) in chickens reared under backyard conditions compared to those reared under CFS. 3. Higher (P < 0.01) crop and gizzard contents were recorded during winter compared to the rainy season. The proportion of grains in the crop during summer and winter season was higher compared to rainy season. Further, there were more insects present in the crop during the rainy season and winter compared to summer. 4. The proportion of insects was higher in chickens reared in humid, subtropical and cool temperate regions compared to semi-arid conditions. The consumption of grasses was higher in cool-temperate regions as compared to those reared under other areas. 5. Crude protein (CP), Ca, P and gross energy (GE) content of the crop were higher in chickens reared under CFS compared to those reared in backyard systems and CP in the crop contents was lower in backyard chickens reared in humid subtropical and semi-arid regions compared to other areas. Similarly, lower (P < 0.01) Ca levels were seen in crop and gizzard contents from birds reared in semi-arid Rajasthan, and P and GE were lower in tropical wet and dry Telangana (TWT) compared to the chickens reared in the backyard conditions in other regions. 6. Based on the results, the nutrient intake for birds utilising the scavenging feed resource base (SFRB) in the TWT region was below the requirements of backyard chickens from the other regions selected in the present study. GE and CP were critically deficient in the SFRB of the TWT region. Therefore, evolving location-specific supplementary diets using locally available feed resources to meet nutrient requirement of backyard chickens is required for optimising production potential. [ABSTRACT FROM AUTHOR]

In the present study, trends and variations in climatic variables (i.e. rainfall, wet day frequency, surface temperature, diurnal temperature, cloud cover, and reference and potential evapotranspiration) were analyzed on seasonal (monsoon and non-monsoon) and annual time scales for the Ajmer District of Rajasthan, India. This was done using non-parametric statistical techniques, i.e. the Mann-Kendall (MK) and Modified Mann-Kendall (MMK) tests, over a period of 100 years. The MK test with prewhitening (MK-PW) of climatic series was also applied to climatic variables and the results were compared to those obtained through the MK and MMK tests in order to assess the performance of trend detection methods. The Pettitt-Mann-Whitney (PMW) test was applied to detect the temporal shift in climatic series. The trend analysis revealed that annual and seasonal rainfall did not show any statistically significant trend at a 10% significant level. A noticeable trend increase was found in wet day frequency, surface temperature and reference evapotranspiration ( ET) during the non-monsoon season from the three non-parametric statistical tests at a 10% significance level. A statistically significant decrease in maximum temperature was found during the non-monsoon season by the MK-PW test alone. This analysis of several climatic variables at the district scale is helpful for the planning and management of water resources and the development of adaptation strategies in adverse climatic conditions. [ABSTRACT FROM AUTHOR]

Land degradation has recently been exacerbated in rangelands of arid Rajasthan by heavy grazing pressures. The total livestock population in the arid region of Rajasthan has reached 29.25 million in the year 2001 from 10.34 million in the year 1951. In terms of adult cattle units (ACU) the livestock pressure was 9.58 million in 1983, which increased to 11.27 million in 2001. Local grazing pressures are surpassing the recommended stocking rates of the rangelands at an enormous pace. The pressure was 0.87 ACU ha-1 in 1981 which increased to 1.02 ACU ha-1 ha in 2001 against the optimum desirable density of 0.2 ACU ha-1. Excellent, good, fair, poor and very poor condition rangelands (having approximate productivity of 2.0, 1.5, 1.0, 0.75, and 0.5 Mg ha-1, respectively) can safely provide year long grazing to 0.25-0.30, 0.20, 0.17, 0.13, and 0.01-0.06 ACU ha-1 blocks, respectively, during normal years. The carrying capacities of the rangelands were estimated several decades ago, however, qualitative evidence is available regarding changes in soil and vegetation patterns. There is need to evolve practices for improving the long-term productivity and sustainability of rangeland ecosystems. An increase of 639% in forage yield was observed over control by adopting moisture conservation technique. Increase in forage yield was recorded in the range of 30 to 122% in "poor" and 29 to 107% in "fair" class rangelands after 3-5 years of reseeding. Premonsoon sowing of grass seeds give 36% higher forage yield over monsoon sowing. Application of 22.5 kg N h-1 during normal year resulted in additional increase in forage yield by 20 to 70%. If sustainable productivity increases are to be achieved, mechanisms must be developed to involve fully range users (herders) in all aspects of project planning and implementation. A flexible stocking rate, dependent on seasonal and annual variation in feed availability, is suggested as a key element in any improved range and livestock management strategy. [ABSTRACT FROM AUTHOR]

Background: Land use change plays a vital role in global carbon dynamics. Understanding land use change impact on soil carbon stock is crucial for implementing land use management to increase carbon stock and reducing carbon emission. Therefore, the objective of our study was to determine land use change and to assess its effect on soil carbon stock in semi-arid part of Rajasthan, India. Landsat temporal satellite data of Pushkar valley region of Rajasthan acquired on 1993, 2003, and 2014 were analyzed to assess land use change. Internal trading of land use was depicted through matrices. Soil organic carbon (SOC) stock was calculated for soil to a depth of 30 cm in each land use type in 2014 using field data collection. The SOC stock for previous years was estimated using stock change factor. The effect of land use change on SOC stock was determined by calculating change in SOC stock (t/ha) by deducting the base-year SOC stock from the final year stock of a particular land use conversion. Results: The total area under agricultural lands was increased by 32.14% while that under forest was decreased by 23.14% during the time period of 1993–2014. Overall land use change shows that in both the periods (1993–2003 and 2003–2014), 7% of forest area was converted to agricultural land and about 15% changes occurred among agricultural land. In 1993–2003, changes among agricultural land led to maximum loss of soil carbon, i.e., 4.88 Mt C and during 2003–2014, conversion of forest to agricultural land led to loss in 3.16 Mt C. Conclusion: There was a continuous decrease in forest area and increase in cultivated area in each time period. Land use change led to alteration in carbon equity in soil due to change or loss in vegetation. Overall, we can conclude that the internal trading of land use area during the 10-year period (1993–2003) led to net loss of SOC stock by 8.29 Mt C. Similarly, land use change during 11-year period (2003–2014) caused net loss of SOC by 2.76 Mt C. Efforts should be made to implement proper land use management practices to enhance the SOC content. [ABSTRACT FROM AUTHOR]

Land cover is a crucial component in assessment of biodiversity and ecosystem services. In arid regions, land cover is mostly composed of aeolian structures which exhibit fragile environmental scenario. The major challenge in this highly dynamic landscape was conversion of desertic land to intensive land use such as agricultural farmlands. To overcome this challenge Indira Gandhi Canal (IGC) and its branches were extended over this district. The main interest of this research was to investigate net primary productivity (NPP) changes using multi-temporal satellite imagery and meteorological datasets within the timeframe of 30 years from 1982 to 2012 over this region. This study was taken up to assess the impact of canal in and around IGC command area in Jaisalmer District to understand the consequence on desertic environment. Analysis of three decades terrestrial NPP over IGC command area in Jaisalmer District, India, shows significant increase in NPP. The satellite data-based analysis of NPP as well as validation with the optical data in the study region revealed that this increasing trend in NPP is basically associated to increase in canal networks. The water supply from the canal gradually led to expansion of irrigation in the agricultural fields leading to change in dynamics of the area. This systematic and long-term NPP analysis will be useful to strengthen our understanding for the role of regional land cover types and impact of their change in the national and global carbon cycle for understanding land degradation and desertification scenario in the study area. [ABSTRACT FROM AUTHOR]

The rural farmers in western Rajasthan State are uneducated and most of the applications of Information and Communication Technology (ICT) are demonstrated and run in the English Language. The majority of these rural farmers who are illiterates with a very low level of understanding of the English Language find it difficult to take advantage of the availability of ICT to facilitate their access to information for their farm businesses. This study examined the role of ICT in enhancing the farmers' access to production and marketing information in western Rajasthan State in India. Primary data was collected from 133 farmers consisting of 71 ICT users and 62 Non-ICT users through questionnaire administration. The results of the Analysis of Variance test regarding the farmers' access to different types of production and marketing information revealed that the user type (i.e., ICT versus Non-ICT user) significantly explains the differences in farmers' access to the different types of marketing and production information. These results are consistent with the empirical results of the student's t-test that farmers' access to different types of production and marketing information from ICT sources is significantly higher than from Non-ICT sources. Consistently, the empirical results of the multiple regressions revealed that the percentage of production and marketing information obtained from ICT sources had positive significant influence on the farmers' access to marketing and production information; and that the percentage of marketing and production information obtained from Non-ICT sources had negative significant influence on the farmers' access to marketing and production information. These results suggest that ICT sources of marketing and production information play a crucial role in the farmers' access to this information for their business operations. The implication is that proper education and training of farmers (especially the female farmers) about the utilization of ICT sources to accelerate access to information is crucial. [ABSTRACT FROM AUTHOR]