Friday, May 31, 2013

Hyderabad Lakes

A shot at a clear water solution

The GHMC, which has taken up a programme for the preservation of 128 lakes within its boundaries, has decided to take up an initiative to clean up at least 60 of these in the first phase, according to GHMC Commissioner M.T. Krishna Babu.

The ‘Hussainsaga’ continues

The dredging of the Hussainsagar lake has been in progress for almost six months without there being any headway on the location of a dump yard for the dredged sediment finalising the site to dump the dredged sediment so far.

Monday, May 27, 2013

Hydroponics - Micronutrients and algal blooms

Hydroponics - Micronutrients and algal blooms

Micro nutrients and algae in Hydroponics -
However, iron, calcium and magnesium deficiencies on leaves and fruit occur even when there is more than a sufficient amount of these elements in a solution. 
Most hydroponic growers come across algae sooner or later.

Phosphate fertilizers are used in large amounts in horticultural, agricultural and turf applications and they are often blamed for algae blooms in rivers and lakes (water carries phosphates and nitrogen fertilizers to these bodies of water). The rapidly growing algae blooms suck oxygen from the water, thus resulting in large fish kills



Of all the amazing substances found on this Earth none are as precious and integral to biological life as water. Water, as we all know, is made up of oxygen and hydrogen atoms, but between the water molecules is a different form of oxygen: molecular oxygen. Molecular oxygen—more commonly known to gardeners as dissolved oxygen—is the oxygen used by aquatic creatures and the aerobic organisms living in and around a plant’s rhizosphere. Water quality evaluations performed for aquatic life applications rate water quality in relation to its dissolved oxygen content—the more dissolved oxygen, the better the water quality. This standard should be applied to water used for plants, too—especially plants in hydroponic systems.
The importance of dissolved oxygen
Good-quality water that includes a high dissolved oxygen content is absolutely crucial to successful indoor horticulture. The most significant benefit of water with a high dissolved oxygen content is the stimulation of beneficial aerobic organisms. Most beneficial microorganisms living in and around a plant’s rhizosphere will only survive, thrive and reproduce in an oxygen-rich environment. Too little dissolved oxygen creates a compounded negative effect—as the beneficial organisms die out because of the lack of dissolved oxygen, the ideal conditions for anaerobic pathogenic organisms are also created. Almost every pathogenic disease related to the plant’s rhizosphere is anaerobic and can be avoided by providing sufficient levels of dissolved oxygen. Another benefit of highly oxygenated water is that dissolved oxygen regulates the availability of certain nutrients—for example, some studies have shown the number of nitrifying microbes increases with the level of dissolved oxygen. Without sufficient dissolved oxygen content, the nitrogen cycle in your soil can be compromised.
Physical factors that affect dissolved oxygen
There are two physical factors that affect dissolved oxygen content relative to indoor horticulture: temperature and salinity. Salinity is less crucial than temperature because by the time a medium or nutrient solution’s salinity level is high enough to affect dissolved oxygen content chances are good that the plant will have already shown signs of over-fertilization or toxic salinity. Temperature, however, is the most crucial and controllable factor associated with dissolved oxygen. Temperature inversely controls the solubility of oxygen in water—in other words, as temperature rises the dissolved oxygen content falls and as temperature decreases the potential dissolved oxygen content increases. If this wasn’t bad enough, the damage is intensified because this inverse relationship with oxygen and water is exponential—so when temperatures rise in your grow room, the dissolved oxygen content in your hydroponic system or grow medium exponentially decreases. This is the number one reason temperature control of the nutrient solution in a hydroponic nutrient reservoir is so crucial.
Temperature control for water
The first way to control the temperature of your water is to control the temperature of the room itself—soil containers, hydroponic systems, hydroponic reservoirs and anything else in the grow room will eventually take on the ambient temperature of the room. This is one of the reasons you see plants grown outdoors in 100°F heat that survive, even flourish, while indoor gardens that reach 100°F usually end up with severe casualties. The plants grown outdoors can withstand 100°F+ temperatures because their roots and the moisture around them are insulated by the ground. The dissolved oxygen and beneficial aerobic organisms in the soil are unharmed by the heat and continue to function, allowing the plant to continue growing. Now take a look at your indoor plants in the same kind of heat. Their roots are in some sort of soil container or hydroponic system, they are completely surrounded by the ambient air in the room and plants, roots, medium and all will eventually become the same temperature as the room—in this case, 100°F+. Once the water in the soil or hydroponic system gets that hot, the dissolved oxygen content is so low that beneficial aerobic organisms will die off and pathogenic anaerobic organisms will find favorable conditions to thrive and destroy your plants. A little-known fact in the indoor gardening industry is that the stress imposed on plants by high temperatures is usually the result of a decline in dissolved oxygen in the medium or hydroponic system—this harms beneficial microbes and in turn harms the plants. By implementing air conditioners, exhaust and intake fans and air cooled reflectors, however, an indoor horticulturalist can effectively control the ambient temperature—which will help to maintain sufficient dissolved oxygen in the medium or hydroponic solution.
Water chillers
Water chillers have become an increasingly popular tool for the hydroponic gardener. Any hydroponic system that is susceptible to heat from the environment or employs large submersible pumps should absolutely be equipped with a water chiller, which is essentially an air conditioner for water. These handy devices—available at virtually any hydroponics retailer in a variety of sizes—are particularly useful when a hydroponic gardener is also supplementing CO2. Optimal ambient temperatures for CO2 enrichment are higher than normal ambient temperatures, so water chillers allow growers to maintain cool temperatures in their hydroponic systems while increasing the room temperature to maximize CO2 absorption. Water chillers also help to battle the unwanted heat created by the large submersible pumps used in some hydroponic systems.
Aeration is how a gardener replaces the dissolved oxygen that is used up naturally during a plant’s growing process—or more specifically, the oxygen used by microbes within the plant’s rhizosphere. Aeration of a nutrient solution—carried out by vigorous circulation or by an air pump connected to an air stone or diffuser—will help replace used dissolved oxygen. As water bubbles up or circulates it comes into contact with the surrounding air, allowing it to absorb some of the molecular oxygen from the atmosphere. Soil growers can amend their soil with perlite, pumice, coco coir or hydroton to create air pockets that will provide pathways for air to enter the medium.
Oxygen additives
There are numerous oxygen booster additives available at your local hydroponics retailer that can help improve the dissolved oxygen content of your nutrient solution. Make sure you read the bottle carefully; some of these oxidizers are designed for cleaning hydroponic systems (with plants removed!) and should not be added to a regular feeding program. Another good choice for oxygen supplementation is hydrogen peroxide or H2O2. Hydrogen peroxide is one of the most common ways to boost dissolved oxygen content in your nutrient solution, but it is also one of the additives most argued about in the hydroponic community. Here’s my rationale: hydrogen peroxide occurs naturally in rain water and has played an integral role in plant and microbial evolution since the beginning of time. Unfortunately, many growers tend to over-apply hydrogen peroxide, which is counterproductive—high concentrations of hydrogen peroxide will create an oxidization effect, which actually kills beneficial organisms. As long as the hydrogen peroxide is well diluted and used in moderation, though, I see no harm in using it as a dissolved oxygen booster.
Of all the factors that determine success for an indoor horticulturalist, none are as elusive as the dissolved oxygen molecule—its significance is out of all proportion to its physical size and any gardener who has battled root rot or experienced diminished yields due to excessive heat will vouch for its importance. Dissolved oxygen supports the healthy lifecycle of the beneficial microbes, which are the hidden pillars of a garden’s success. By implementing temperature control, aggressive aeration and the supplementation of oxygen-boosting additives, indoor growers can maintain high populations of beneficial microbes, avoid potential problems and maintain optimal conditions in their gardens.

Friday, May 17, 2013

Russia seeks Baltic pollution partnerships

Russia seeks Baltic pollution partnerships

Russia's push to create public-private partnerships as a way to help clean up the polluted Baltic Sea is the focus of an environmental summit this week in St. Petersburg.

ST. PETERSBURG, Russia, April 5 (UPI) -- Russia's push to create public-private partnerships as a way to help clean up the polluted Baltic Sea is the focus of an environmental summit in St. Petersburg.

The meeting, to be attended by Russian Prime Minister Dmitry Medvedev and premiers from 10 other Baltic and northern European nations, is being called in part to strengthen international cooperation on tackling the chronic environmental woes of the Baltic, which is plagued by nitrates and phosphates from waste run-off.

The nutrients, contained in fertilizers and sewage, enter the sea from large "spot" sources such as wastewater treatment facilities and also from diffuse sources, such as scattered farm fields.

Environmentalists say the pollution is causing the "eutrophication" of the Baltic Sea, though which algae blooms deplete oxygen from the water, triggering fish die-offs and creating a 25,000-square-mile-wide "dead zone" the size of Latvia.

A 2007 action plan developed by the Helsinki Commission of nine Baltic Sea nations has achieved a 40 percent reduction in direct nitrogen and phosphorus discharges as well as a 40 percent decrease in airborne nitrogen emissions.

Some 200 Baltic Sea anti-pollution commitments have been at previous summits, including 11 by sovereign states.

But to achieve its stated objective of eliminating the Baltic's algae blooms, direct phosphorous and nitrogen inputs must be cut by a further 42 percent.

Nitrate-reduction targets adopted under the Helsinki Commission agreement cover the Baltic proper, the Gulf of Finland and Bornholm Basin. Targets have been set for oxygen "debt," which is a measure of a lack of oxygen caused by eutrophication. The ultimate aim is to reach a level of oxygen debt that was prevalent in the 1950s to 1970s.

Russia, which holds the rotating presidency of the Council of the Baltic Sea States, has indicated it will use the prime ministerial conference to promote its top priority of establishing international public-private partnerships to tackle environmental challenges.

A release from the Russian delegation, headed by Igor Vdovin, board chairman of the National Agency for Direct Investment, said they will be focused on building such partnerships for environmental projects in two pilot regions -- Kaliningrad and St. Petersburg/Leningrad Oblast.

The Russians said they will be also be seeking to create a "common space" for public-private partnerships in the Baltic Sea region as well as a regional investment fund among the 11 Baltic Sea states attending the event as well as the European Commission.

Finland, which launched the environmental summit process in 2010 and takes over the Council of the Baltic Sea States presidency this year, says it's aiming to speed up the implementation of the Helsinki Commission's clean-up action plan.

Finnish Prime Minister Jyrki Katainen and Minister of the Environment Ville Niinisto were both set to travel to St. Petersburg, the government said Tuesday.

Katainen in November called for closer links between the Baltic Sea countries to combat maritime pollution at an address in Jyvaskyla, the Finnish daily Keskisuomalainen reported.

"The question is to save the Baltic Sea," he said, calling it the biggest challenge facing the surrounding nations. "For it to achieve good ecological status will require closer cooperation and, above all, the cutting down of (nutrient) load factors."

Niinisto, meanwhile will also be present at the Russian-hosted public private partnership forum, the governing National Coalition Party reported in its online magazine.

Sunday, May 12, 2013

What Good is a Diatom
What Good is a Diatom

"Breweries, cough syrup, paint, plastic, insecticides, toothpaste, polishes, ... concrete, animal feed, fertilizers, ... dynamite. It is astounding where the remains of diatoms can be found. One might say that many of the wheels making modern life go 'round are studded with the vacant shells of these tiny phytoplankton, which are used as filters, fillers, insulation, and mild abrasives."
"Diatom shells (more correctly called frustules) are composed of silica, the essence of glass. Because of this their beauty whipped Victorian era microscopists into giddy covetousness. But most frustules escaped the diatom connoisseurs' slides by sinking to the ocean or lake floor after the diatom died."
"Diatoms supply the oxygen in every fourth breath you take. Diatoms are critical in the ecological food chain of streams, lakes and oceans. It's thought diatoms could help slow Earth's current warming trend; scientists have suggested that seeding the ocean with iron to stimulate diatom reproduction could help remove carbon dioxide from circulation."

Friday, May 10, 2013

Huge toxic algae bloom expected for Lake Erie

Huge toxic algae bloom expected for Lake Erie

Scientists are warning that conditions are perfect for a bumper crop of algae to grow in Lake Erie this summer.

They say heavy April showers are washing fertilizer off farm fields into the water in larger amounts, and those chemicals feed algae blooms that starve the lake of oxygen. Feeding on phosphorus, algae produces bad smells and toxins that are absorbed by underwater life, choking it off.

"There's a 99 per cent chance, there's a strong chance, that [we will] have very bad algae this year," said Raj Bejankiwar, a scientist with the International Joint Commission.

The warning comes two years after Lake Erie experienced the worst algae blooms on record.

By the numbers

Approximately 40 million people live around the Great Lakes.
About 73 million tourists visited the Great Lakes in Ontario in 2010.
About $12.3 billion was injected into the economy by those tourists.
Source: IJC

Blooms are traditionally confined to the summer months, mainly August. Last year, however, warmer temperatures in March allowed algae to grow earlier in the year, but the bloom wasn't as big as the one witnessed in 2011.

This year, April rain could cause as big a bloom as the one from two years ago. Heavy spring rain was to partially blame for that one, too.

Phosphorus gets from the fields to the lakes in one of three ways:

Blown there by the wind.
Soaking through the soil, entering the ground water and flowing into rivers and lakes.
Rain washes it off the top of the soil and directly into rivers and lakes.

Bejankiwar is the lead on the Lake Erie Ecosystem Priority, a branch of the IJC that is studying algae levels in Lake Erie. He said it's normal to have some algae in the lake, but not massive blooms.
Bejankiwar said extra nutrients that feed algae also come from sewage treatment plants, recreational properties and golf courses. He said most of the phosphorus comes from farm run-off.

It's not much phosphorus per farm or per hectare, but it adds up, says one professor.
"If we're talking about the amount a farmer would lose, we're talking less than a few grams per hectare," said Ivan O'Halloran, a professor at Ridgetown College.
O'Halloran said that one kg of phosphorus run-off can have a "significant impact" on algae levels.

'No fertilizer police'
He said one way farmers try to decrease the amount of phosphorus that ends up in the lakes is to make sure they only put what they need into the soil. Soil tests can be done to see how much fertilizer is necessary.

However, there are no "fertilizer police," and best management practices are not laws: they are suggestions, O'Halloran said. That all makes it hard to regulate the distribution of fertilizer.

Henry Denotter, a Kingsville farmer, plants ground cover in the fall to keep the fertilizer from washing into the ditch. After the wheat is harvested, Denotter plants beets and clover in his wheat field to keep the soil in place. Even then, some phosphorus always escapes, he said.
"We do whatever we can to try and retain it, but we have to stay in business, too," Denotter said.
Denotter said it's impossible to keep all the fertilizer in the soil and dire predictions from scientists won't change that.
He thinks scientists should recognize there is only so much farmers can do.
Denotter already uses GPS to determine where he needs to fertilize; uses soil tests to determine how much fertilizer he needs; and uses what he calls a "no-till" system, where he doesn't turn up the earth.
Denotter said it's in farmers' best interest to do what they can to keep the phosphorus in the soil because it costs about $700 per tonne.

Last fall, the Essex Region Conservation Authority and Windsor-Essex County Environment Committee launched an educational campaign about blue-green algae. It's called Overload: Lake Erie Blue Green Algae.