Berlin, Oct 22 (ANI): A new study on landscape around Chesapeake Bay, the largest estuary in the US, has determined that imbalance in nitrogen cycle due to the widespread use of fertilizers is damaging water quality and fish populations.

Professor Grace Brush, from Johns Hopkins University in Baltimore, USA, undertook the study of landscape changes around Chesapeake Bay.

Professor Brush studied the organisms and materials preserved in sediments in Chesapeake Bay spanning 1000 to 14,000 years, alongside available historical records covering the past 300 years, to trace the history of changes to nitrogen loading in the estuary.

She highlights how population growth, agricultural expansion, and urbanization have released nitrogen from the land and moved it to Chesapeake Bay, where it has accumulated and degraded both the natural wildlife and water quality.

The combination of the increasing use of fertilizers, deforestation and the draining of wetlands and floodplains to provide more land for crops, has led to an imbalance in the nitrogen cycle, in particular reduced opportunities for the natural removal of nitrogen.

As a result, there is an excess of nitrogen in the estuary, also known as eutrophication.

This in turn has led to the deterioration of the local ecosystem through reduced concentrations of oxygen in the bay, affecting both the water quality and the fish populations.

Providing food for an increasing population is the main reason for these changes, according to Professor Brush. Although the estuary supplied an abundance of fish species, humans also need plant-based food products in their diets, hence the increase in grasslands and use of fertilizers.

Brush adds that aquatic deterioration is not unique to Chesapeake but a global phenomenon.

Marine "dead zones" with low oxygen and/or toxic algae, caused primarily by the run-off of fertilizers from the land, as well as a greater reliance on fossil fuel, are on the increase.

Brush concludes her review by looking at the likely implications of this imbalanced nitrogen cycle on future ecosystems as well as ways to improve water quality.

She recommends multiple processes to reduce nitrogen accumulation, both natural and engineered, and notes that ultimately the decision to proceed will come down to politics.

According to Brush, the future of the Chesapeake and coastal regions in general will depend very much on the recognition of the importance of nitrogen removal for goals other than restoring the fishery and how successful the various tools for nitrogen removal are. (ANI)

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London, October 22 (ANI): A 10ft high solar- and wind-powered home, which can stroll at walking pace across all terrains, may help deal with problems like floods and unfriendly neighbours in future.

The prototype home has been built on six hydraulic legs that can walk. It has a living room, kitchen, toilet, bed, and wood stove.

A mainframe computer helps control the house's legs.

The pod is all set to take its maiden stroll around rural Cambridgeshire at the Wysing Arts Centre in Bourn on Thursday.

Its makers - art collective N55 in Copenhagen, Denmark - developed it while working with engineers at MIT in Massachusetts, USA.

They say that the prototype house provides a solution to the problem of rising water levels as it can simply walk away from floods.

It costs about 30,000 pounds to build the prototype.

The designers, however, think that the cost of its production can be reduced.

"This house is not just for travellers but also for anyone interested in a more general way of nomadic living," the Telegraph quoted one of its designers at the MIT as saying.

Each leg of the prototype house works independently. They are so designed that three stay on the ground at any one time to ensure stability.

The makers hope the legs could be eventually mounted on any kind of structure, and several pods could be linked together for bigger houses. (ANI)

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Berlin, Oct 22 (ANI): A new research by Japanese and German scientists has determined that climate change will have different effects on lakes in warmer and colder regions of the globe.

The research was undertaken by Scientists from Hokkaido University, the Hokkaido Institute of Environmental Sciences, Kagoshima University and the Helmholtz Centre for Environmental Research (UFZ), who compared current measurements with measurements taken 70 years ago.

This confirmed a rise in temperatures in the deep water layers of lakes in the south of Japan, while the deep water temperatures of lakes in the north remained the same.

Rising temperatures can lead to changes in nutrient exchange and turnover in the water.

In certain circumstances, winter circulation behaviour can be so severely affected by rising temperatures and other climatic factors that oxygen supplies to the lower depths become insufficient for many organisms, leading to an accumulation of nutrients in the deep water, according to the researchers.

Measurements from 2005 and 2007 in deep Japanese caldera lakes provide information about the distribution of dissolved nutrients in the water.

There are two reasons why this chain of lakes makes an excellent research subject for providing general information about circulation under changeable climatic conditions that will be valid for lakes outside the research area.

Firstly, the lakes cover a climate gradient that stretches from the south of Japan to the northern island of Hokkaido.

Secondly, oxygen and nutrient exchange between the deep water and the surface in the lakes under investigation is controlled almost exclusively by temperature differences.

The researchers found that almost all of the lakes studied displayed a good distribution of the dissolved nutrients, despite their enormous depths of up to 423 metres (Lake Tazawa, Honshu).

The lakes can be divided into two main depth-circulation categories based on their climatic conditions.

The researchers expect deep water temperatures of colder lakes (e.g. Lake Shikotsu, Hokkaido) to remain unchanged in warmer winters, provided the temperature rises are not excessive, while deep water temperatures in warmer lakes are likely to rise.

This was confirmed by comparisons with single-point measurements from the 1930s.

The scientists warn that a very steep rise in winter temperatures over the years results in water temperatures that do not fall anywhere near as low as the temperatures of the previous years and depth circulation can cease altogether (Lake Ikeda, Kyushu).

In such circumstances oxygen supplies and nutrient distribution would be interrupted, which would have impacts on organisms. (ANI)

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Washington, Oct 22 (ANI): A team of cosmologists from the University of the Basque Country has determined that the accelerated expansion of the Universe can be explained by dark 'phantom' energy.

To explain the majority of the phenomena occurring in the Universe, complicated calculations with a computer are required and which have to be based on appropriate mathematical models.

This is what the Gravitation and Cosmology research team at the University of the Basque Country (UPV/EHU) is involved in: analyzing models capable of explaining the evolution of the Universe.

One of the phenomena that standard models of physics have not yet been able to explain is that of the accelerated expansion of the Universe.

Although Einstein proposed a static model to describe the cosmos, today it is well known, thanks to supernovas amongst other things, that it is, in fact, expanding.

By measuring the quantity of light that gets to us from a supernova, we can calculate its distance from us, and its colour indicates the speed at which it is distancing itself from us.

The more reddish it is, the faster it is travelling. In other words, comparing two supernovas, the one that is distancing itself more slowly from us is a more bluish colour.

According to observations by astrophysiscists, besides supernovas distancing themselves from us, they are doing so more and more rapidly, i.e. distancing themselves at an accelerated velocity, just like the rest of the material of the Universe.

The energy known to exist in the Universe, however, is not sufficient to cause such acceleration.

Thus, the theory most widely accepted within the scientific community is that there exists a 'dark energy', i.e. an energy that we cannot detect except by the gravitational force that it produces.

In fact, it is believed that 73 percent of the energy of the Universe is dark.

The unique characteristic of dark energy known to us is that it possesses repulsive gravitational force. That is, unlike the gravity we know on Earth, this force tends to distance stars, galaxies and the rest of the structures of the Universe from each other.

This would explain why the expansion of the Universe is not constant, but accelerated.

Such powerful dark energy is known as phantom energy, with which the Universe is able to expand to such an extent that the structures we know today would disappear.

This research group considers that the phantom energy model may be the most suitable to explain the accelerated expansion of the Universe. (ANI)

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