Friday, May 29, 2009

NASA Satellite Detects Red Glow to Map Global Ocean Plant Health


[Fig. Ocean scientists can now remotely measure the amount of fluorescent red light emitted by ocean phytoplankton and assess how efficiently the microscopic plants are turning sunlight and nutrients into food through photosynthesis. (picture source http://www.nasa.gov/)
WASHINGTON -- Researchers have conducted the first global analysis of the health and productivity of ocean plants using a unique signal detected by NASA's Aqua satellite.
Ocean scientists can now remotely measure the amount of fluorescent red light emitted by phytoplankton and assess how efficiently these microscopic plants turn sunlight and nutrients into food through photosynthesis. Researchers also can study how changes in the global environment alter these processes at the center of the ocean food web. Single-celled phytoplankton fuel nearly all ocean ecosystems, serving as the most basic food source for marine animals. Phytoplankton account for half of all photosynthetic activity on Earth and play a key role in the balance of carbon dioxide in the atmosphere. The health of these marine plants affects the amount of carbon dioxide the ocean can absorb from the atmosphere and how the ocean responds to a changing climate. "This is the first direct measurement of the health of the phytoplankton in the ocean," said Michael Behrenfeld, a biologist who specializes in marine plants at Oregon State University. "We have an important new tool for observing changes in phytoplankton every week, all over the planet." All plants absorb energy from the sun, typically more than they can consume through photosynthesis. A small fraction of this extra energy is re-emitted as fluorescent light in red wavelengths. Using the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Aqua satellite, scientists have now observed "red-light fluorescence" over the open ocean. MODIS is the first instrument to observe this signal on a global scale. "The amount of fluorescent light emitted is not constant; it changes with the health of the plant life in the ocean," said Behrenfeld. Scientists previously used satellite sensors to track the amount of plant life in the ocean by measuring the amount and distribution of chlorophyll. "Chlorophyll gives us a picture of how much phytoplankton is present," said co-author Scott Doney, a marine chemist from the Woods Hole Oceanographic Institution in Woods Hole, Mass. "Fluorescence provides insight into how well they are functioning in the ecosystem." With this new measurement, the scientists discovered large areas of the Indian Ocean where phytoplankton were under stress from iron deficiency. They were surprised to see large portions of the ocean "light up" seasonally as phytoplankton responded to a lack of iron in their diet. The amount of fluorescence increases when phytoplankton have too little iron, a nutrient in seawater. Iron reaches the sea surface on winds blowing dust from deserts and other arid areas, and from upwelling currents. The research team detected new regions of the ocean affected by iron deposition and depletion. In the fall and winter and especially the summer, significant southwesterly winds over the Indian Ocean stir up ocean currents and bring more nutrients up from the depths for the phytoplankton to feed on. At the same time, the amount of iron-rich dust delivered by winds is reduced. Climate change could mean stronger winds pick up more dust and blow it to the sea, or less intense winds leave waters dust-free. Some regions will become drier and others wetter, changing the regions where dusty soils accumulate and get swept up into the air. Phytoplankton will reflect and react to these global changes. "On time-scales of weeks to months, we can use this data to track plankton responses to iron inputs from dust storms and the transport of iron-rich water from islands and continents," Doney said. "Over years to decades, we also can detect long-term trends in climate change and other human perturbations to the ocean." These findings appeared in the May edition of the journal Biogeosciences.
Fore more information :

Saturday, May 23, 2009

Radioactive gas Radon may affect the people of Ranchi city in India.

Radon problem cannot be ruled out in the houses of Ranchi city in India.
by
Dr. Nitish Priyadarshi
Fig. House build on the rocks in Ranchi city.
Earth has many ways to kill us. We keep on the lookout, and rightly so, for volcanic eruptions, earthquakes, landslides, flooding, cosmic impacts, climate change and falling rocks on the highway. Should we still worry about radon?
You remember radon—that radioactive gas that comes up from the soil and collects in basements and ground floors, sometimes in well water. Radon is a prominent villain in many countries. Blamed for tens of thousands of deaths from lung cancer. Like asbestos, radon was looked at more kindly when it was new, and today it too is more feared than it deserves.
Radon Geology:
To the geologist, radon is interesting, not worrisome. For one thing, radon starts with uranium, which is worth knowing about for its energy content and its important role in the Earth's heat budget.

Uranium turns to lead via a long, slow cascade of nuclear decay, and radon sits at an important point in that process.

Not only does the radon nuclide decay quickly, with a half-life less than four days, but the next four nuclides in the cascade decay with a combined half-life less than an hour. In other words, radon packs a powerful dose of radioactivity, and because it is a gaseous element, it can drift out of the minerals where it forms into the air. Thus it's a good signal of uranium, even for buried deposits.

Humans have always been exposed throughout their period of existence to naturally occurring ionising radiation. Specifically, naturally occurring radionuclides are present in variable amounts in our environment. To assess radiological health hazards, naturally occurring radionuclides are being measured in soil, sand, marble, bricks etc throughout the world.

Terrestrial radiation comes from radioactive elements that were present at the time the earth was formed. They continue to decay and form additional radioactive materials.
Unusual soil composition has increased background radiation twenty-five fold or more in a few areas in the world. Locations with high background radiation in the soil, mainly from uranium, include the Rocky Mountains, Kerala India, coastal regions of Brazil, granite rock areas of France, and the northern Nile Delta.

Seeing the rock types and its mineral composition Radon problem cannot be ruled out in the houses of Ranchi city of Jharkhand State in India. This fact was justified by a published report of Research Reactor Institute, Kyoto University, Japan. According to the report Air-gamma dose rate was 0.30 μSv/h on the surface in the densely populated area in the city. In Ranchi the concentration of K-40 (potassium-40) and thorium is high. Concentration of Radium-226 was 75 Bq/Kg in the soils.

Very interesting thing in the Ranchi city is that name of one of its major road is RADIUM ROAD. Till today no body knows from where did this name came from. Name of this road exists from the British rule in India i.e. before 1947.

Seeing the presence of apatite, sphene and zircon in the Ranchi rocks, presence of Uranium cannot be ruled out. According to the report Uranium concentration is also high in Ranchi. All these concentrations are of natural origin. Radioactivity in the bricks made by the local soil may pose threat to the people living in the houses made by these bricks.

When Uranium is there, presence of Radon cannot be ruled out. It is radioactive gas that comes up from the soil and collects in basements and ground floors, sometimes in well water. Radon is a prominent villain in the United States, blamed for tens of thousands of deaths from lung cancer.
Even the granites of the Daltonganj area of Jharkhand state contain anomalous uranium values. Uranium mineralization has also been observed in the granitic rocks comprising the southern periphery of the Hutar basin of Daltonganj area. The Proterozoic granitoids, forming the provenance for the Hutar and Auranga subbasin, have been analyzed which revealed uranium content up to 520 ppm. ( Virnave, 1999).
The radon in home indoor air can come from two sources, the soil or water supply. The radon in water supply poses an inhalation risk and an ingestion risk. Research has shown that risk of lung cancer from breathing radon in air is much larger than the risk of stomach cancer from swallowing water with radon in it. Most of the risk from radon in water comes from radon released into the air when water is used for showering and other household purposes.
Radon in home water in not usually a problem when its source is surface water. A radon in water problem is more likely when its source is ground water, e.g., a private well or a public water supply system that uses ground water.
From last several years people of Ranchi are becoming more dependent on ground water for their daily uses. Indiscriminate deep borings are rampant in the granite rocks of Ranchi city. People are going more and more deeper for search for water.
People of Jharkhand state are unaware of danger from Radon gas.
Radon loves fractures because they set it free. Solid mineral grains are a pretty good trap for gases, but break the grains and the gas escapes. So just having rocks rich in uranium is not enough—they must be fractured, too.
Ranchi rocks are filled with fractures and joints. Ground waters are mined through these fractures and joints. So threat of Radon Poisoning looms large in Ranchi city.

Even the houses build on the rocks filled with cracks and fractures are under threat of Radon poisoning inside the house. Most of the radon indoors is contributed by the ground underneath buildings.
The amount of radon entering buildings from the ground is influenced by the following four factors.
a) Radon concentrations in soil gas: This depends on the concentration of the immediate precursor of Rn-222, Ra-226, in rocks and soils. Elevated levels of radium are found in some granites, limestone's and sandstone's and other geologies.
b) Permeability of the ground: This depends on the nature of the rock and soil under the building Disturbed ground can have greatly increased permeability. Usually the radon comes from the ground within a few metres of the building, but if the ground is particularly permeable or fissured it may come from a greater distance.
c) Entry routes into homes: Concrete floors often have cracks around the edges and gaps around services entries such as mains water supply, electricity or sewage pipes. If homes have suspended timber floors the gaps between the floorboards are the major route of entry. Pathways for soil gas to enter houses are often concealed, and vary between apparently identical houses.
d) Under-pressure of homes: Atmospheric pressure is usually lower indoors than outdoors owning to the warm indoor air rising; this creates a gentle suction at ground level in the building through the so-called `stack effect'. Wind blowing across chimneys and windows can also create an under-pressure (the `Bernoulli effect'). The result is that the building draws in outside air, typically at the rate of one air change per hour. Most of this inflow comes through doors and windows, but perhaps 1% or so comes from the ground. In an average house, this amounts to a couple of cubic metres of soil gas entering the house each hour. The radon concentration in a building depends on the rate of entry of the radon and the rate at which it is removed by ventilation. Increasing the ventilation rate will not always decrease the radon concentrations, however, because ventilation rate and under-pressure are related, and some ways of increasing ventilation, such as the use of extract fans or opening upstairs windows, can also increase the under-pressure.

Recently high concentrations of radioactive gas radon have been detected in Bengalooru’s groundwater, which means a higher risk of stomach cancer for those who drink it.A team from the Bangalore University and the Baba Atomic Research Centre in Mumbai collected 78 samples of water from bore wells, shallow wells, surface water and the supplied drinking water in Bengalooru. More than half the samples contained radon in concentrations up to a thousand times the permissible limit of 11.1 Becquerel per litre.

In the case of Bengalooru (old name Bangalore) it is the large reserves of granite that is causing the problem. Being highly soluble, radon easily dissolves in groundwater. The rate at which radon is released from rocks depends on the porosity of the rocks and the intensity of water flow.
Radon is a cancer-causing natural radioactive gas that we can’t see, smell or taste. Its presence in the home can pose a danger to family's health. Radon is the leading cause of lung cancer among non-smokers. Radon is the second leading cause of lung cancer in America and claims about 20,000 lives annually.
Any home can have a radon problem. This means new and old homes, well-sealed and drafty homes, and homes with or without basements. In fact, people and their family are most likely to get greatest radiation exposure at home. That is where they spend most of their time. Jharkhand government should come forward to analyze the amount of Radon present in groundwater and in the air inside the house.
Sources:
Virnave, S.N. Nuclear Geology and Atomic Mineral Resources. Bharati Bhawan, Patna. 169.
http://www.epa.gov/iaq/radon/
http://www.epa.gov/radon/healthrisks.html
http://www.epa.gov/radon/pubs/hmbyguid.html#6.
http://www.radonguide.com/sources-of-radon-in-buildings.html
http://www.downtoearth.org.in/full6.asp?foldername=20090215&filename=news&sec_id=4&sid=21

Tuesday, May 19, 2009

Ranchi city of India is facing acute water crisis.

Water has decreased in Dams, Ponds and Rivers.
by
Dr. Nitish Priyadarshi


Surface Water has reduced in Kanke Dam

Flow of water in Kanke Dam has also reduced


All the small rivulets flowing through Ranchi city has dried up.


No water in rivulet

Water reduced in one of the important ponds of Ranchi city.
No water in local ponds

Inhabitants of Ranchi city of Jharkhand state of India are facing acute water crisis. Most of the dug wells and deep wells and the corporation taps of this populated area have run dry forcing people to consume polluted surface water. Extensive deforestation, urbanization and industrilisation has led to uneven spread of rainfall, on which the water supply from the dams to the city area is depended. Even the ground water table has been affected due to uneven rainfall. From last few years rainfall due to western disturbances during winter season has shown decline trend. This rainfall earlier used to recharge groundwater which helped to maintain water table in peak summer season.

This summer season most of the ponds and small rivulets flowing through the city has dried up due to unbearable hot temperature. Earlier Ranchi was known for its cool climate even in the summer season. Temperature rarely went up to 41 degree centigrade. But now it is very common. It is a fact that before 1990s whenever temperature rose to 35 degree centigrade during day time, Ranchi plateau used to get evening rainfall which helped to recharge the ground water table as well as surface water table. But now this phenomenon has stopped. Now continuous dry season last for more than six months. From last few years the temperature is showing increasing trend.

The main reasons for this water scarcity are as follows:

Dams: There are three major dams (Kanke, Rukka and Hatia) in Ranchi city which is now filled with sediments affecting water table. Due to these sedimentations the storage capacity of all the three dams have decreased many fold. From the year of their constructions silts have never been removed which has not only depleted the water table but also made dame water contaminated.

Topography: General elevation of Ranchi city is 600 m. above the mean sea level and has a flat to gently undulating topography with occasional ridges. The Ranchi plateau gradually slopes down towards south east into the hilly and undulating region of Singhbhum. Due to this uneven topography the rain water are lost through surface runoff resulting in less water percolation below the surface. The thin soil layer of Ranchi plateau which is becoming more thin due to weathering is gradually loosing its water retaining capacity.

Geology and Urbanisation: The process of urbanization and industrilisation from last 20 years has caused changes in the water table as a result of decreased recharge and increased withdrawal. Many of the small ponds which were main source of water in the surrounding areas are now filled for different construction purpose affecting the water table. Lots of DEEP- BORING in the Ranchi city has also forced the water table to move down as well as Ranchi plateau consists of metamorphic rocks which are relatively impermeable and hence serve as poor aquifers. They bear groundwater only in their weathered top portion which rarely exceeds 10 meters.
Rainfall factor: Though Ranchi receives sufficient amount of rainfall (1000mm to 1200 mm every year) but it is not an accurate indicator of groundwater level changes. Recharge is the governing factor (assuming annual withdrawals are constant); it depends on rainfall intensity and distribution and amount of surface runoff. As Ranchi is the plateau area waste of rainwater in the form of surface runoff varies from 35% to 40%. So recharging is not so good.

Many houses have been built over the recharge area which are the major source of water to unconfined aquifer below, because an unconfined aquifer is one in which a water table varies, depending on areas of recharge and discharge and pumping from the wells.
Among the natural drinking water sources are ponds and lakes that too has their life span, is being threatened by early Eutrophication due to sedimentation, which hampers bottom discharge processes. Pollution growth of Algal bloom, weeds in the remaining ponds of Ranchi has made water unfit for domestic use imparting fowl smell.

The state of Jharkhand, although claims to be a store house of minerals in India, is not so rich in water resources. Most of the areas are occupied by the hard rock, which is in general protracted drought prone areas.

Hard rock which occupies major portion of the Jharkhand plateaus are devoid of primary porosity and occurrence and movement of groundwater is controlled by the joints, fractures and fissures present in them.

The need of the day is to conserve every drop of water and recharge the depleted aquifers. Mere slogan shouting will not carry us far. The time is now ripe for action with the involvement of the people who are beneficiaries.

Half- hearted attempts are being made at rainwater harvesting in Ranchi city and with much publicity given in the media. The scheme can benefit thousands of acres of arid lands, if small ponds are excavated at vantage points or small check dams are build in at particular intervals in the different rivulets to conserve soil moisture.

Remedies:

1. Identification of the recharge area or catchment areas in and around Ranchi city to ensure no further construction on those lands.
2. Construction of artificial water reservoirs in suitable area in and around Ranchi to collect the rain waters.
3. Cleaning of ponds, lakes, rivulets and dams periodically to rejuvenate their capacity of storage of water.
4. Providing proper consultancy to determine suitable areas for deep boring and hand pumps.
5. To ensure regular safe drinking water supply from the Municipal to stop reckless deep boring, because in absence of water supply people are forced go for alternative source of drinking water.
6. Water conservation measures from domestic level.
7. Metering and pricing of water.
8. Region wise, in-depth study of the water balance.
9. Further planning of plantation and aforestation to ensure regularity of water cycle.
10. Fostering an awareness of water as a scare resource and its conservation as an important principle-through NGOs.






Monday, May 11, 2009

Thunderstorm with heavy rains lashes Ranchi city of India.

Many houses and trees destroyed in few seconds thunder and storms.
by
Dr. Nitish Priyadarshi
Today at 1:15 noon severe rain with high velocity of wind with hailstorm suddenly kept people of Ranchi under fear. It was type of hurricane with remained only for few seconds but made great loss to the people. Force of the wind was so strong that it twisted one of the tree in circular road. Asbestos were seen flying in the sky. Impact was so great that even the Iron rod pillars with advertisement board were also seen flying. It was caused by the low pressure and strong winds. Storms are created when a center of low pressure develops, with a system of high pressure surrounding it. This combination of opposing forces can create winds and result in the formation of storm clouds, such as the cumulonimbus. Small, localized areas of low pressure can form from hot air rising off hot ground, resulting in smaller disturbances such as dust devils and whirlwinds.From last few days the temperature of Ranchi city was above 41 degree centigrade which is unusual as Ranchi was known as the summer capital of Bihar, Jharkhand united before 1970s.
Heavy rain with hailstorm lashes Ranchi city.

Thundering blow of air entering into the house of the author.

Patient trapped inside the Van

Houses and shops destroyed

Water logged in the backyard of the authors house


Twisted tree


Streets are blocked due to uprooted trees

Friday, May 8, 2009

Similarities in concept of evolution of life on earth in Dashavatar and modern Geology.

There are many similarities between two theories.
by
Dr. Nitish Priyadarshi
Mankind has long sought to learn how, when and where life originated; and plants have come into existence.
Until the middle of the nineteenth century life was presumed to be created by some supernatural power either once or at successive intervals.
The biblical story of creation of world within six days was put forward by Spanish monk Father Sudrez. He described that the earth and heaven were created on the first day and sky on the second day. Third day the earth surface dried and the ancestors of plants and animals originated. The Sun, the moon, and the stars were created on the fourth day, the birds and the fishes appeared on the fifth day and finally man and beasts were created on the sixth day of creation. In the end of seventh day a woman was constructed from the 12th rib of the man.
According to Hindu mythology the world was created by God Brahma. Gods, men and devils developed from His head; birds from His chest; goats from His mouth, and plants from the hairs of the body.
According to ancient and mediaeval beliefs the life is distributed throughout the cosmos in the form of resistant spores of living forms, the Cosmozoa. These reached the earth accidentally from some other planets, and on getting favourable conditions for life these developed into organisms.
The entire life span of earth is called the geologic time. Plants and animals have changed gradually during the passage of geologic time and present a chronological sequence of events, which led to the evolution of more and more complex from the simple ones. These evolutionary changes are read in the form of fossils that are found in succeeding rock beds on the strata.

In Hindu mythology the concept of biological evolution (from fish to modern man) is clearly shown in the form of Dashavatar (ten avatars of Lord Vishnu). If we compare it with geologic time scale of biological evolution, there are few similarities. According to Dashavatar the first avatar of Lord Vishnu was in the form of fish on this earth. If we compare it biological events on different Geological Time Scale first developed life was also in the form of fish which originated during Cambrian period.

Second avatar was in the form of Tortoise(reptiles). In geology also first reptiles comes as second important evolution which originated in Mississippian period just after Amphibians.

Third avatar was in the form of Boar. In Tertiary periods all the big mammals originated.


Narasimha, the Man-Lion (Nara= man, simha=lion) was the fourth avatar. But in geology no such evidences are mentioned. It may have been related with Ape Man The term may sometimes refer to extinct early human ancestors, such as the undiscovered missing link between apes and humans.

Fifth avatar was in the form of Vamana, the dwarf man. It may be related with the first man originated during Pliocene. It may be related with Neanderthals. Neanderthals were generally only 12 to 14 cm (4½–5½ in) shorter than modern humans, contrary to a common view of them as "very short" or "just over 5 feet".


Parashurama, the man with an axe was the sixth avatar. It has the similarities with the first modern man originated during Quaternary period or the man of Iron age.
Lord Rama the prince of Ayodhya , Lord Krishna and Lord Buddha were the other avatars of Lord Vishnu. It indicates the physical and mental changes and evolution in the man from its time of appearance.

There may be difference in opinion regarding comparing time of evolution of different spices in Dashavatar and modern geological time scale. But it is also true that most of the sequence of evolution is same. Only difference is that in Dashavatar there is no concept of Dinosaurs or birds.
Sources:
Rastogi, V.B. 1988. Organic Evolution. Kedar Nath Ram Nath, New Delhi.
Cvancara, A.M. 1995. A field manual for the amateur geologist. John Wiley & sons, Inc. New York.
http://encyclopedia.farlex.com/_/viewer.aspx?path=hut&name=aa325261.jpg
http://www.topnews.in/files/Neanderthal.jpg
http://i6.photobucket.com/albums/y223/NigelWaring/Misc/BFMM340.jpg