Pollen analysis of 1.75 m deep sediment core from Tula-Jalda (Amarkantak) in Anuppur district, Madhya Pradesh shows that around 4500–3600 cal years BP, this region supported open mixed tropical deciduous forests comprising chiefly Madhuca indica followed by Terminalia, Mitragyna parvifolia, Haldina cordifolia, Emblica officinalis and Acacia, under a warm and relatively less humid climate. The retrieval of Cerealia and other cultural plants, viz. Artemisia, Cheno/Am and Caryophyllaceae signifies that the region was under cereal-based agricultural practice.

The deep ocean was once assumed to be lifeless and barren. Today we know that even the deepest waters teem with living creatures, some of them thought to be little changed from when life itself first appeared on the planet. The deep ocean is also essential to the earth’s biosphere—it regulates global temperatures, stores carbon, provides habitat for countless species, and cycles nutrients for marine food webs. Currently stressed by pollution, industrial fishing, and oil and gas development, these cold, dark waters now face another challenge: mining.

Forty years after the ocean floor was first mapped by hand, a team of Australian researchers has created the first digital map of the entire sea floor. Made by the University of Sydney's School of Geosciences and National ICT Australia (NICTA), the map can be used to plot the planet's underwater carbon sinks and understand how oceans respond to climate change.

Knowing the patterns of distribution of sediments in the global ocean is critical for understanding biogeochemical cycles and how deep-sea deposits respond to environmental change at the sea surface. We present the first digital map of seafloor lithologies based on descriptions of nearly 14,500 samples from original cruise reports, interpolated using a support vector machine algorithm. We show that sediment distribution is more complex, with significant deviations from earlier hand-drawn maps, and that major lithologies occur in drastically different proportions globally.

The Bengal Basin evolved as a rift-controlled extensional basin along the NNE–SSW trending Basin Margin Fault coevally with the 85 East Ridge in the Bay of Bengal during the short-lived hotspot activity south of Bhubaneswar. The basin opening post-dated the Kereguelen Plume magmatism (at ~116 Ma), but predated the phase of continental collision that triggered the rise of the Himalaya in the north. Supply of sediments in the initial stages of basin opening was from the west, mainly through the denudation and erosion of the uplifted Precambrian Shield.

An ecomorphodynamic model was developed to study how Avicennia marina mangroves influence channel network evolution in sandy tidal embayments. The model accounts for the effects of mangrove trees on tidal flow patterns and sediment dynamics. Mangrove growth is in turn controlled by hydrodynamic conditions. The presence of mangroves was found to enhance the initiation and branching of tidal channels, partly because the extra flow resistance in mangrove forests favours flow concentration, and thus sediment erosion in between vegetated areas.

Movement of nutrients across ecosystem boundaries can have important effects on food webs and population dynamics. An example from the North Pacific Rim is the connection between productive marine ecosystems and freshwaters driven by annual spawning migrations of Pacific salmon (Oncorhynchus spp).

Riverine export of particulate organic carbon (POC) to the ocean affects the atmospheric carbon inventory over a broad range of timescales. On geological timescales, the balance between sequestration of POC from the terrestrial biosphere and oxidation of rock-derived (petrogenic) organic carbon sets the magnitude of the atmospheric carbon and oxygen reservoirs. Over shorter timescales, variations in the rate of exchange between carbon reservoirs, such as soils and marine sediments, also modulate atmospheric carbon dioxide levels.

The northeastern part of the Indian Ocean, i.e. the Bay of Bengal (BoB) is located near some of the most complicated tectonic zones on the Earth. An earthquake of magnitude ~6.0 occurred on 21 May 2014 near the coast of Odisha. Occasional moderate to large earthquakes in BoB highlight the need to study precise hypocentre locations, and focal mechanisms to understand the cause of intraplate seismicity in BoB.

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