Banni Grasslands Research Articles

Mid-late Holocene vegetation response to climatic drivers and biotic disturbances in the Banni grasslands of western India

Tropical grasslands and savannas are globally extensive, and are of significant environmental, economic, and ecological importance. These ecosystems are anticipated to be particularly sensitive to future changes in climate, and understanding how these systems have responded to climatic changes in the past can provide us with insights into their potential responses to future global change. In this study, the temporal dynamics of C3-C4 vegetation changes in response to changes in moisture availability, local fire events and changing levels of herbivory in a summer-rainfall region of Western India are reconstructed for the past ~4600calyrBP. Paleodata such as stable carbon isotope of bulk organic matter (δ13Corg), oxygen isotope from carbonate shells (δ18Oshell), macro-charcoal and herbivore dung fungal spores are reported from the retrieved cores of two wetland sites located in the Banni grasslands of Western India. Results show that vegetation in the Banni was composed mostly of C3 vegetation from ~4600 to ~2500calyrBP, after which there was a decline in C3 vegetation. From the late-Holocene to the present, there was a mix of both C3 and C4 vegetation, with C4 grasses being more abundant in the ecosystem. These shifts were coincident with rainfall changes from more mesic conditions during ~4600 to ~2500calyrBP to more arid conditions towards the present as indicated by δ18Oshell isotope data. The period of increase in C4 vegetation also coincides with a period of increased biotic disturbances in the ecosystem, particularly fire. Given the current scenarios of global warming, recurrent drought events and increased anthropogenic use of similar ecosystems, such studies can provide us insights into potential future trajectories of these ecosystems.

New Record of Agamid Lizard <i>Trapelus agilis</i> (Olivier, 1804) (Squamata: Agamidae) from Gujarat, India

We report sightings of the agamid lizard Trapelus agilis (Olivier, 1804) commonly known as the Brilliant Ground Agama, from the state of Gujarat in India. Trapelus agilis is known to be present in the state of Rajasthan from India, but its presence in Gujarat had not been confirmed due to absence of substantial records beside one old record from 1880s. We report sightings of T. agilis on two separate occasions in the years 2014 and 2015 from the region of Banni grasslands in Kachchh district of Gujarat. The observations and the nature of the habitat are described in detail. These recent sightings prompt for a systematic survey of T. agilis in the Kachchh landscape in India.

New record of Agamid Lizard Trapelus agilis (Olivier, 1804)(Squamata: Agamidae) from Gujarat, India

We report sightings of the agamid lizard Trapelus agilis (Olivier, 1804) commonly known as the Brilliant Ground Agama, from the state of Gujarat in India. Trapelus agilis is known to be present in the state of Rajasthan from India, but its presence in Gujarat had not been confirmed due to absence of substantial records beside one old record from 1880s. We report sightings of T. agilis on two separate occasions in the years 2014 and 2015 from the region of Banni grasslands in Kachchh district of Gujarat. The observations and the nature of the habitat are described in detail. These recent sightings prompt for a systematic survey of T. agilis in the Kachchh landscape in India.

Damage due to the Mw 7.7 Kutch, India earthquake of 2001

This paper presents a study of the damage due to the M w 7.6–7.7 intraplate Kutch earthquake of 26 January 2001. It was a powerful earthquake with a high stress drop of about 20 MPa. Aftershocks (up to M 4) have continued for 2.5 years. The distribution of early aftershocks indicates a rupture plane of 20–25 km radius at depths of 10–45 km along an E–W-trending and south-dipping hidden fault situated approximately 25 km north of the Kutch Mainland Fault. The moment tensor solution determined from regional broadband data indicates reverse motion along a south-dipping (by 47°) fault. The earthquake is the largest event in India in the last 50 years and the most destructive in the recorded history in terms of socioeconomic losses with 13,819 deaths (including 14 in Pakistan), collapse/severe damage of over a million houses and US$10 billion economic loss. Surface faulting was not observed. However, intense land deformations have been observed in a 40×20-km meizoseismal area. These include lateral spreading, ground uplifts (about a meter), ground slumping and deep cracks. Liquefaction with ejection of sand and copious water was widespread in the Banni grassland, Rann areas (salt plains), along rivers and also in the coastal areas up to 200 km distance from the epicenter in areas of intensity VII to X+. Stray incidences of liquefaction have occurred up to distances of at least 300 km. For the first time in India, multistory buildings have been destroyed/damaged by an earthquake. The maximum acceleration is inferred to be 700 cm/s 2 and intensities are 1–3 units higher in soil-covered areas than expected from the decay rate of acceleration for hard rock.

Grassland mapping/monitoring of Banni, Kachchh (Gujarat) using remotely-sensed data

Abstract In India 12-15 million ha of land, i.e., 3-7 per cent of the total geographical area, has been recorded as permanent pasture or grazing land. In recent years, the factors responsible for gradual loss of grassland are expanding agriculture, overstocking of domestic animals at a phenomenal rate and improper pasture and grazing land management. However, in an agriculture-based economy, like that of India, a judicious ratio has to be maintained amongst grasslands, croplands and forestlands, in order to obtain optimum results in socio-economic and ecological terms. The acquisition of sufficient and timely information on these resource components is of prime importance for judicious planning. Remote sensing data, which is now available at regular intervals, assumes a great significance. To understand the above-mentioned facts a pilot study has been conducted in the Banni grassland areas of the Kachchh district. Banni, at one time considered the largest grassland of its kind in Asia, has fallen upon sad...