Great Rann Of Kachchh Research Articles

Drought Assessment Using Remote Sensing Techniques in the Great Rann of Kachchh and Adjoining Areas of Thar Desert

Drought Assessment Using Remote Sensing Techniques in the Great Rann of Kachchh and Adjoining Areas of Thar Desert

Update to Floral Diversity at Gujarat Institute of Desert Ecology (GUIDE) Campus Along with New Distribution of Salsola Oppositifolia Desf. in Kachchh

This study explores the biodiversity dynamics within the prestigious Gujarat Institute of Desert Ecology (GUIDE) campus in Bhuj, India, over the span of eight years. Fieldwork conducted during pre-monsoon and post-monsoon periods revealed a significant increase in plant species, genera, and families compared to previous assessments. The taxonomic diversity analysis revealed 239 plant species representing 180 genera and 62 families, with trees, herbs, and shrubs contributing prominently. Fabaceae appeared as the dominant family, followed by Poaceae and Malvaceae. Comparative analysis with previous studies established changes in species composition, notably an increase in tree species and a decrease in herbs. Of particular interest is the discovery of the second distribution of Salsola oppositifolia Desf. on the campus, a plant species first recorded in India in 2022 from Great Rann of Kachchh. The study highlights the crucial role of urban green spaces in supporting biodiversity. With 239 plant species thriving within the campus's urban infrastructure, this study highlights the potential of urban forestry in promotion biodiversity conservation and ecological resilience. Future research directions include exploring the ecological roles of vegetation and development public awareness about the multi-layered benefits of plants beyond oxygen production.

Middle to Late Holocene palaeoenvironmental evolution of the western Great Rann of Kachchh, India: Insights from ichnology, geochemistry, and sedimentology

To understand the palaeoenvironmental changes during the Middle to Late Holocene period, we have carried out multiproxy analysis integrating ichnology, geochemistry, and sedimentology in the Great Rann of Kachchh (GRK). The exposed cliff sections of Rann sediments and overlying Bet sediments are explored and analysed for the characteristics of the sedimentary sequences and ichnological assemblages. Seven recurring ichnotaxa are documented, which comprise of Arenicolites, Paleophycus, Planolites, Psilonichnus, Skolithos, Teichichnus, and Thalassinoides. The ichnological and sedimentological findings were supported by obtained geochemical results, which were then compared with the existing chronological data. The trace fossils associated with the bottom of the Bet Zone and the top surface of the Great Rann sediment units (Middle Holocene) suggest the shallow marine depositional environment. Further, the monospecific occurrence of Teichichnus in the middle units (Middle to Late Holocene period) of the Bet Zone sediments suggests the brackish water environmental conditions associated with the high discharge of fluvial system leading to lowering of salinity. The topmost unit of the Bet Zone sediments shows the disappearance of trace fossils suggesting a terrestrial depositional condition. The present work suggests that the area of the western GRK has witnessed a gradual shifting of shallow marine to the fluvial environment during the Middle to Late Holocene period.

Holocene paleoenvironmental changes in the marginal marine basin of Great Rann of Kachchh, western India: Insights from sedimentological and mineral magnetic studies on a ∼60 m long core

We carried out sedimentological and mineral magnetic studies on a ∼60 m long core recovered from the central part of the Great Rann of Kachchh (GRK), a marginal marine basin, located on the western continental margin of India to understand the Holocene paleoenvironmental changes. We critically analysed the sedimentation pattern, sediment characteristics along with paleoclimatic signatures of global and regional relevance. In GRK basin, the sedimentation started in early Holocene (∼10.6–9.3 kyr BP) under rapidly rising post glacial sea level with very high sedimentation rate (8.71 cm/yr to 2.37 cm/yr) which is also seen in several marginal marine basins across the globe. The abundant laminations, coarse grained sediment flux and environmental magnetic parameters (χlf, S-ratio) suggests that the sedimentation occurred in developing monsoonal conditions under wetter yet fluctuating climate during this period. After ∼9 kyr BP, the environmental magnetic proxies show transition toward relatively wetter condition with peak at ∼6.5 kyr BP. This wetter climatic phase on the other hand corroborates with reduction of sedimentation rate to 0.46 cm/yr. This reduction in sedimentation rate under strengthening monsoonal conditions probably occurred due to rapid filling up of the basin on account of earlier high sedimentation in the basin. The sedimentation rate is reduced significantly after the onset of aridity at ∼4 kyr BP except a minor wet spell recorded during ∼1.5 to 1 kyr BP before drying of the GRK basin.

Did the Harappan settlement of Dholavira (India) collapse during the onset of Meghalayan stage drought?

ABSTRACTRadiocarbon dating of archaeological carbonates from seven cultural stages of Dholavira, Great Rann of Kachchh (GRK), the largest excavated Harappan settlement in India, suggests the beginning of occupation at ~5500 years BP (pre‐Harappan), and continuation until ~3800 years BP (early part of the Late Harappan period). The settlement rapidly expanded under favourable monsoonal climate conditions when architectural elements such as the Citadel, Bailey, Lower and Middle Town were added between the Early and mid‐Mature Harappan periods. Abundant local mangroves grew around the GRK sustaining prolific populations of the edible gastropod Terebralia palustris. Oxygen isotope (δ18O) sclerochronology of Early Harappan gastropod shell suggests seasonal mixing of some depleted (δ18O ~ −12‰) river water in summer/monsoon months (through ancient Saraswati and/or Indus distributary channels) with seawater that periodically inundated the GRK. Evaporation from this semi‐enclosed water body during the non‐monsoon months enriched the δ18O of water/shell carbonates. The humid fluvial landscape possibly changed due to a catastrophic drought driving the final collapse of the settlement of Dholavira exactly at the onset of the Meghalayan (Late Holocene) stage (~4300–4100 years BP). Indeed, Dholavira presents a classic case for understanding how climate change can increase future drought risk as predicted by the IPCC working group. Copyright © 2019 John Wiley & Sons, Ltd.

New evidence of early Iron Age to Medieval settlements from the southern fringe of Thar Desert (western Great Rann of Kachchh), India: Implications to climate-culture co-evolution

Two hitherto unexplored settlements at Karim Shahi and Vigakot are reported from the uninhabited hyper-arid region of the western Great Rann of Kachchh (GRK), located near southern fringe of Thar Desert, Gujarat, NW India. The archaeological evidence, supported by radiocarbon and optical chronology indicate presence of settlement from the Early Iron Age to Early Historic (~3100–2300 years B.P.) and Historic to Medieval (~1500–900 years B.P.) periods. This would imply that following the Harappan decline, the GRK was still a hospitable terrain for the sustenance of human settlements' during the Early Iron Age. Isotopic and micro-botanical evidence indicate that relatively higher rainfall than today sustained the hydrological system until around the Medieval period. We propose that the early withdrawal of the late Holocene Inter Tropical Convergence Zone (ITCZ) and resultant monsoon decline accounts for the abandonment of settlement in the western (Sindh-Baluchistan) domain. As a consequence, the rivers in the western domain dried early, while the fluvial system in the southern/eastern domain (Sorath/Cholistan in Gujarat/Ghaggar-Hakra-Nara interfluve) was sustained due to monsoonal rain at least up to 1600 years B.P. The settlements were subsequently disrupted due to a combination of hyper-arid climate and infrequent tectonic activity sometime between the late Medieval and recent time. The settlement migration in the southern/eastern domain, as far into the Rann and desert fringe during this period was possibly a nonpareil ancient analogue of modern “climate refugee and refugia” (Warner, 2011; Morelli et al., 2016) induced by anthropogenic climate change.

Unravelling the Hidden Truth from Vigukot in the Great Rann of Kachchh, Western India by Surface and Sub-Surface Mapping

Unravelling the Hidden Truth from Vigukot in the Great Rann of Kachchh, Western India by Surface and Sub-Surface Mapping

Tracing the Vedic Saraswati River in the Great Rann of Kachchh

The lost Saraswati River mentioned in the ancient Indian tradition is postulated to have flown independently of the Indus River into the Arabian Sea, perhaps along courses of now defunct rivers such as Ghaggar, Hakra and Nara. The persistence of such a river during the Harappan Bronze Age and the Iron Age Vedic period is strongly debated. We drilled in the Great Rann of Kachchh (Kutch), an infilled gulf of the Arabian Sea, which must have received input from the Saraswati, if active. Nd and Sr isotopic measurements suggest that a distinct source may have been present before 10 ka. Later in Holocene, under a drying climate, sediments from the Thar Desert probably choked the signature of an independent Saraswati-like river. Alternatively, without excluding a Saraswati-like secondary source, the Indus and the Thar were the dominant sources throughout the post-glacial history of the GRK. Indus-derived sediment accelerated the infilling of GRK after ~6 ka when the Indus delta started to grow. Until its complete infilling few centuries ago, freshwater input from the Indus, and perhaps from the Ghaggar-Hakra-Nara, probably sustained a productive marine environment as well as navigability toward old coastal Harappan and historic towns in the region.

Sources and depositional pathways of mid-Holocene sediments in the Great Rann of Kachchh, India: Implications for fluvial scenario during the Harappan Culture

The decline of the Harappan Culture (5300-3300 yrs BP), one of the earliest urban settlements, has often been linked to the demise of a perennial river (vedic Saraswati?) that originated in the Himalayan Mountain Belt and flowed through the Thar Desert into the Arabian Sea. To test this hypothesis we have studied the mid-Holocene (5.5–1.0 ka) sedimentation history of the Great Rann of Kachchh, an uplifted former gulf of the Arabian Sea, which is believed to have housed the delta of the river. Using trace element geochemistry and Sr-Nd isotopic ratios of sediments as tracers we have determined their provenances. Results of our study suggest that the basin received significant sediment contributions (20–30%) from a distinct sub-Himalayan source, apart from the other proximal sources such as the river Indus, Thar Desert and the ephemeral river Luni. It, however, did not receive any sediment from an independent glacier-fed river. Based on geological and geochemical arguments we infer that these sub-Himalayan sediments could have only been transported through a continuous Ghaggar-Hakra-Nara river channel, possibly seasonal, that flowed through the Harappan heartland. The fact that there was no major change in fluvial sedimentation in the Great Rann of Kachchh and it persisted at least until ∼1.0 ka, suggests that drying up of this river system may not have been the primary cause for the decline of the civilization.

Late Pleistocene–Holocene clay mineral record from the Great Rann of Kachchh basin, Western India: Implications for palaeoenvironments and sediment sources

The present study uses clay mineralogy to delineate a ∼17 ka record of palaeoenvironmental/palaeoclimatic changes in the recently uplifted palaeogulf of Arabian Sea i.e. Great Rann of Kachchh (GRK). Situated on continental margin of Indian subcontinent and flanked by Indus delta, the GRK basin has preserved continuous record of post glacial sedimentation. Clay mineral studies on two long cores (∼60 m and 50 m long) show more abundance of physical weathering products (illite and chlorite) over the chemical weathering products (smectite and kaolinite). We show that the GRK sediments depict multiple sources of sediment input. Dominance of illite-chlorite suggests GRK received sediments dominantly from the Himalayan terrain with minor contribution from adjacent regions. We present the oldest clay mineralogical signature of an interval of intensified monsoon conditions during the late Pleistocene (∼17.7–16.3 cal ka B.P.). Monsoon became stronger before ∼8.4 cal ka B.P., and whereas the mid Holocene weakening of monsoon occurred after ∼7 cal ka B.P. Despite the differences in source region and composition of clay mineral records from the GRK with northeastern and southeastern Arabian Sea, the sedimentation responded to major climatic shifts that have occurred since the LGM.

Morphotectonic control on Quaternary sedimentation and landscape evolution, Pachham Island, Kachchh, Western India

Pachham Island is the westernmost island in a chain of four rocky islands within the Great Rann of Kachchh that are bounded in the north by the Island Belt Fault (IBF). The island is characterized by two parallel and structurally controlled Kaladungar hill range and Goradungar hill range separated by a synclinal central valley. The central valley has acted as a sink for the Quaternary sediments. The island is transversely traversed by a N-S trending basement high termed as Median high that shows pronounced geomorphic and drainage anomaly. The Quaternary sediments comprise coarse-grained colluvio-fluvial deposits, miliolite, and sandy alluvium. The coarse-grained Quaternary deposits were primarily derived from the colluvium generated due to the uplift of the Kaladungar hill range and Goradungar hill range along the IBF and Goradunagar Fault, respectively. The colluvial debris were subsequently reworked, transported down slope and deposited in the central valley. The presence of the deeply incised valleys in Quaternary sediments, two levels of terrace surfaces over the Median high, and the raised Rann floor surrounding the island suggest a dominant role of neotectonics in the landscape evolution and Quaternary sedimentation.

Satellite image based quantification of invasion and patch dynamics of mesquite (Prosopis juliflora) in Great Rann of Kachchh, Kachchh Biosphere Reserve, Gujarat, India

The invasion of alien species is a significant threat to global biodiversity and the top driver of climate change. The present study was conducted in the Great Rann of Kachchh, part of Kachchh Biosphere Reserve, Gujarat, India, which has been severely affected by invasion of Prosopis juliflora. The invasive weed infestation has been identified using multi-temporal remote sensing datasets of 1977, 1990, 1999, 2005 and 2011. Spatial analyses of the transition matrix, extent of invasive colonies, patchiness, coalescence and rate of spread were carried out. During the study period of three and half decades, almost 295 km2 of the natural land cover was converted into Prosopis cover. This study has shown an increment of 42.9% of area under Prosopis cover in the Great Rann of Kachchh, part of the Kachchh Biosphere Reserve during 1977 to 2011. Spatial analysis indicates high occupancy of Prosopis cover with most of the invasion (95.9%) occurring in the grasslands and only 4.1% in other land cover types. The process of Prosopis invasion shows high patch initiation, followed by coalescence, indicating aggressive colonization of species. The number of patches within an area of < 1 km2 increased from 1977 to 2011, indicating the formation of new Prosopis habitats by replacing the grasslands. The largest patch of Prosopis cover increased from 144 km2 in 1977 to 430 km2 in 2011. The estimated mean patch size was 7.8 km2 in 1977. The mean patch size was largest during 2011, i.e., 9 km2. The annual spread rate for Prosopis has been estimated as 2.1% during 2005–2011. The present work has investigated the long term changes in Prosopis cover in the Great Rann of Kachchh, part of Kachchh Biosphere Reserve. The spatial database generated will be useful in preparing strategies for the management of Prosopis juliflora.

Microbial Activity and Culturable Bacterial Diversity in Sediments of the Great Rann of Kachchh, Western India

The Great Rann of Kachchh, a vast expanse of salt desert in Western India is a unique hostile ecosystem posing an extreme environment to life forms due to high salt content, hyper-arid climate, seasonal water logging and extremes of temperature. In the virtual absence of natural vegetation, soils and sediments of Rann of Kachchh are microbially dominated ecosystems. In the present study microbial activity and the diversity of cultivated heterotrophic bacteria were investigated in the sediments collected along a 5-m exposed section at Khadir Island in the Great Rann of Kachchh. Microbial activity (as an index of sediment enzymes) was found to be high in the middle of the section (200-280 cm). Dehydrogenase (DHA), substrate-induced DHA and alkaline phosphatase activities revealed the oligotrophic nature of the basal portion (320-480 cm). Abundant bacterial isolates obtained from different depths were found to be clustered in 12 different phylogenetic groups by amplified ribosomal DNA restriction analysis. 16S rRNA gene sequencing revealed the dominant bacterial ribotypes to be affiliated to Firmicutes (Families Bacillaceae and Staphylococcaceae) and Actinobacteria (Family Brevibacteriaceae) with minor contribution of Proteobacteria (Families Phyllobacteriaceae and Bartonellaceae), pointing their endurance and adaptability to environmental stresses. Statistical analysis indicated that sediment organic carbon, salinity, total available nitrogen and total available phosphorous are most likely critical determinants of microbial activity in the Khadir Island sediments.

Ground Penetrating Radar imaging of two large sand blow craters related to the 2001 Bhuj earthquake, Kachchh, Western India

The 2001 Bhuj earthquake (Mw 7.7) formed several medium to large sand blow craters due to extensive liquefaction of the sediments comprising the Banni plain and Great Rann of Kachchh. We investigated two large closely spaced sand blow craters of different morphologies using Ground Penetrating Radar (GPR) with a view to understand the subsurface deformation, identify the vents and source of the vented sediments. The study comprises velocity surveys, GPR surveys using 200 MHz antennae along three selected transects that is supplemented by data from two trenches excavated. The GPR was able to provide good data on stratigraphy and deformation up to a depth of 6.5 m with good resolution. The GPR successfully imaged the subsurface characteristics of the craters based on the contrasting lithologies of the host sediments and the sediments emplaced in the craters. The GPR also detected three vertical vents of ∼ 1 m width continuing throughout the profile which are reflected as high amplitude vertical events. We conclude that the large sand blows during the 2001 Bhuj earthquake were produced due to liquefaction of sediments in the subsurface at > 6.5 m depth and that the clay-rich sediments of the Banni plain have behaved as the fine grained cap over it. The present study provides a modern analogue for comparing the liquefaction features of past great earthquakes (for example, the 1819 earthquake) that have occurred in the Kachchh region to understand the phenomena of liquefaction.