Nitrogen availability is a pivotal control on terrestrial carbon sequestration and global climate change. Historical and contemporary views assume that nitrogen enters Earth’s land-surface ecosystems from the atmosphere. Here we demonstrate that bedrock is a nitrogen source that rivals atmospheric nitrogen inputs across major sectors of the global terrestrial environment.

Bed sediment samples were collected along the 9.5 km long inlet channel of Chilika lagoon, east coast of India during low freshwater discharge and low rainfall condition. Distributions of bed sediment along with its texture were studied in detail. Bivariate plots between mean, sorting, skewness and kurtosis of sediments revealed definite grouping pattern. The study, through C-M plot, indicates that the prime factors for transportation of sediment within inlet channel of Chilika lagoon are rolling and bottom suspension during period of low discharge and low rainfall (November-June).

Increased energy demand has led to plans for building many new dams in the western Amazon, mostly in the Andean region. Historical data and mechanistic scenarios are used to examine potential impacts above and below six of the largest dams planned for the region, including reductions in downstream sediment and nutrient supplies, changes in downstream flood pulse, changes in upstream and downstream fish yields, reservoir siltation, greenhouse gas emissions and mercury contamination.

A likely consequence of global warming will be the redistribution of Earth’s rain belts, affecting water availability for many of Earth’s inhabitants. We consider three ways in which planetary warming might influence the global distribution of precipitation. The first possibility is that rainfall in the tropics will increase and that the subtropics and mid-latitudes will become more arid. A second possibility is that Earth’s thermal equator, around which the planet’s rain belts and dry zones are organized, will migrate northward.

Coastal zones are dynamic interfaces of land and water of high ecological diversity and critical economic importance. The boundaries, shape and size of this coast change constantly under the influence of both natural and anthropogenic factors. The study area, Tupilipalem is one of the proposal sites for constructing a major port, to be named Dugarajapatnam Port, along the east coast of Andhra Pradesh, India.

Original Source

The West Antarctic Ice Sheet is one of the largest potential sources of rising sea levels. Over the past 40 years, glaciers flowing into the Amundsen Sea sector of the ice sheet have thinned at an accelerating rate, and several numerical models suggest that unstable and irreversible retreat of the grounding line—which marks the boundary between grounded ice and floating ice shelf—is underway.