Monday, 21 July 2008
Wednesday, 18 June 2008
The Importance of Animals or Beasts
What is it about animals that they "get through" to the most severely impaired children? How can animals reach a human mind dead-ened to anything else? It's not mystical or spiritual, but elementary biology. Animals are and always have been throughout our evolution the most stimulating, fascinating things in the world around us. Today, dulled as we are by the high-tech, fast-paced world we have made for ourselves, we see animals as remote and irrelevant.
We may not have animals consciously on our minds very often today; nonetheless they are alive at the deepest levels of our consciousness. Their importance to the human mind and culture is well known to art historians, folklorists and anthropologists.
The animal presence was best explained by biologist Paul Shepard in his 1978 book, Thinking Animal Animals, he said, got our attention more than anything else in nature as we were evolving. "Animals," Shepard wrote, "are among the first inhabitants of the mind's eye. They are basic to the development of speech and thought. Because of their part in the growth of consciousness, they are inseparable from the series of events in each human life. indispensable to our becoming human in the fullest sense."
Throughout our evolution, animals have helped us come to terms with the strange and wonderful world around us. When we lived as foragers with Earth-bound religions, animals were the First Beings and world-shapers, and the teachers and ancestors of people. When we became agriculturists and looked to the heavens for instruction about the seasons and the elements, we saw animal forms among the stars. Of the 48 Ptolemaic constellations, all but a few are organic, and 25 are named for animals. Of the 22 more that were added in the 17th century, 19 have animal names. When we built colossal earthworks to appeal to the power in the heavens, we built them in animal forms.
In Ice-age eaves, the first art shows the human fascination with animal forms. Animals were thought to embody the spirits and powers of nature, and, as art historians know, animals have been used to symbolize nature ever since. In ancient Egypt, Hathor, the cow goddess of the sky, was believed to have given birth to the sun. The sky was seen as a giant cow, her legs the four corners of the world. Ancient astronomers explained the workings of the universe by reference to the zodiac, which means, literally, "the circle of animals." Universally, animals have bonded us to the rest of the living world.
Animals must feed and empower the human mind like nothing else, for we see their presence also in children's toys, in nursery rhymes, in Aesop's fables, and in other moral tales. And we see the animal presence in language, where they provide the basis for some 5,000 expressions.
A GRADUAL ALIENATION
We tend not to think about the importance of animals anymore. In taking over the world, we have marginalized animals, reduced them from kinfolk, powers, and spirits to commodities, sources of spare parts and pests. Animals no longer matter -- or so we like to think.
But they do matter, and in powerful ways that we need to understand if we are to come to terms with nature. In reducing animals' stature, we reduced all of nature and constructed a world view in which people are above and apart from nature. This "dominionist" worldview was built, most agree, during the transition from foraging to farming that occurred between 10,000 and 5,000 years ago. Marginalizing animals was a cornerstone of the whole edifice, for more than any other agricultural development, it broke up the old ideas of kinship and continuity with the living world.
When early herders and farmers intensified their uses of animals, they needed ways to suppress their older beliefs in animal spirit-powers. People were, after all, gradually enslaving their former gods, teachers and ancestors. Before animals could become tools and commodities, they had to be brought down from their pedestals. Over time, the emerging culture came up with a new set of beliefs about animals' essential evil and baseness. Those combined to form an attitude of hatred and contempt for animals.
Today, we describe serial killers and other criminals as "animals" or "beasts" when we want to describe their lust, cruelty or senseless violence -- all behaviors that are, nature writer John Rodman notes, "more frequently observed on the part of men than of beasts."
We may not have animals consciously on our minds very often today; nonetheless they are alive at the deepest levels of our consciousness. Their importance to the human mind and culture is well known to art historians, folklorists and anthropologists.
The animal presence was best explained by biologist Paul Shepard in his 1978 book, Thinking Animal Animals, he said, got our attention more than anything else in nature as we were evolving. "Animals," Shepard wrote, "are among the first inhabitants of the mind's eye. They are basic to the development of speech and thought. Because of their part in the growth of consciousness, they are inseparable from the series of events in each human life. indispensable to our becoming human in the fullest sense."
Throughout our evolution, animals have helped us come to terms with the strange and wonderful world around us. When we lived as foragers with Earth-bound religions, animals were the First Beings and world-shapers, and the teachers and ancestors of people. When we became agriculturists and looked to the heavens for instruction about the seasons and the elements, we saw animal forms among the stars. Of the 48 Ptolemaic constellations, all but a few are organic, and 25 are named for animals. Of the 22 more that were added in the 17th century, 19 have animal names. When we built colossal earthworks to appeal to the power in the heavens, we built them in animal forms.
In Ice-age eaves, the first art shows the human fascination with animal forms. Animals were thought to embody the spirits and powers of nature, and, as art historians know, animals have been used to symbolize nature ever since. In ancient Egypt, Hathor, the cow goddess of the sky, was believed to have given birth to the sun. The sky was seen as a giant cow, her legs the four corners of the world. Ancient astronomers explained the workings of the universe by reference to the zodiac, which means, literally, "the circle of animals." Universally, animals have bonded us to the rest of the living world.
Animals must feed and empower the human mind like nothing else, for we see their presence also in children's toys, in nursery rhymes, in Aesop's fables, and in other moral tales. And we see the animal presence in language, where they provide the basis for some 5,000 expressions.
A GRADUAL ALIENATION
We tend not to think about the importance of animals anymore. In taking over the world, we have marginalized animals, reduced them from kinfolk, powers, and spirits to commodities, sources of spare parts and pests. Animals no longer matter -- or so we like to think.
But they do matter, and in powerful ways that we need to understand if we are to come to terms with nature. In reducing animals' stature, we reduced all of nature and constructed a world view in which people are above and apart from nature. This "dominionist" worldview was built, most agree, during the transition from foraging to farming that occurred between 10,000 and 5,000 years ago. Marginalizing animals was a cornerstone of the whole edifice, for more than any other agricultural development, it broke up the old ideas of kinship and continuity with the living world.
When early herders and farmers intensified their uses of animals, they needed ways to suppress their older beliefs in animal spirit-powers. People were, after all, gradually enslaving their former gods, teachers and ancestors. Before animals could become tools and commodities, they had to be brought down from their pedestals. Over time, the emerging culture came up with a new set of beliefs about animals' essential evil and baseness. Those combined to form an attitude of hatred and contempt for animals.
Today, we describe serial killers and other criminals as "animals" or "beasts" when we want to describe their lust, cruelty or senseless violence -- all behaviors that are, nature writer John Rodman notes, "more frequently observed on the part of men than of beasts."
A sample essay on The Importance of Animals
Essay by Anita Misra, (1997)
Ever since the dawn of time man and animals have co-existed in the same environment. Scientifically, man himself is classified as an animal with similar needs. Although animals have killed man and man has hunted animals alike, theirs is a symbiotic relationship which cannot be refuted whatever age or time.
In Charles Darwin's theory of evolution, the existence of a conducive eco-system is highly dependent on the interaction between man and beast.
Different types of animals occupy various strata in the food chain of which man is invariably a part. Man relies on animals for food. Most people eat chicken, beef, mutton and pork as well as eggs and milk.
The very existence of man and the nourishment he needs from the time he is a baby comes mostly from animals.
Vegetarians and vegans have argued that they do not rely on animals for food. This is a false assumption as the vegetables and plants that feed the people are highly dependent on animals. In the wild, the animals eat the plants; if no animals ate the plants, there would be an overcrowding of weeds which would lead to the unhealthy development of plant life, resulting in an imbalance in the eco-system.
Animals also help in dispersing the seeds of fruits and vegetables in excretion. This helps to ensure that there is a continuity in the abundance of plant life. The circle of life is held in place by the animals, ie. the animals eat the plants, the animals help the plants reproduce and man eats both the animal and the plant. The faeces of the animals also help in the growth of the plants. When animals die, their decaying bodies also provide nourishment for the plants which in turn nourish the human beings. In vegetable farms, most organic fertilizers also come from decaying animal and plant matter.
Besides food, man also relies on animals for his livelihood. This can be analysed in two ways: indirectly and directly. Agriculturally based countries such as Australia and Argentina rely on some animals to get rid of other animals which might harm their crops. For instance, following the agriculture downturn in Argentina, state authorities released hundreds of foxes to kill the rabbits which were devouring agricultural produce in the field itself and causing great losses to the farmers.
Farmers also use animals, eg. oxen, to plow their land.
More directly, many people use animals as a means of living.
In India hundreds of thousands of people train animals to perform on the streets. Monkeys, cobras and donkeys provide a source of income for their owners and entertainment for the public. The circus works on this concept. Which circus will thrive without the wonderful pantheon of animals? The zoo and the Night Safari also use animals to entertain as well to collect revenue from the tourist industry to pump into the economy. Policemen also use animals like dogs for sniffing out drugs or carrying out search and rescue.
Animals are also crucial in the education of mankind. Medical students often use animals in the laboratory sessions to effectively understand concepts of anatomy. In scientific research, animals are used as guinea pigs to test a product before it is used on humans.
This has often been labelled the exploitation of animals but the importance of using animals to test new products is undeniable. Although human life is placed above that of animals, the necessity of animals to ensure certain aspects of safety for man is critical.
The social standing of man in some ways can be gauged from animals.
If a man has two oxen in India, he is given due respect and if he were to lose the oxen, it would be akin to losing his honour. In the olden days, even today, the possession of horses was considered a great achievement. In medieval France, if a man were to lose his horse due to sheer carelessness, he would often mete out severe punishment upon himself. Using animals to gauge social status might seem frivolous and flippant on the surface, but it has been practised for thousands of years and the importance of animals serving this function will continue in strong focus.
Animals also help develop the emotional and psychological well-being of people. Many people who keep pets such as dogs develop a strong emotional bonding with the animals. They tend to embrace qualities such as sensitivity and loyalty. Of course this is not true with some people who are prone to violent behaviour around animals but studies have shown that most people who have pets around them tend to be gentler, kinder and more loyal. They also develop a sense of responsibility. Children who have pets grow up, often taking these characteristics with them.
Animals also have a therepeutic quality which makes them good healers together with medicine. Some years ago, a girl in Ohio was suffering from high fever with no sign of recovering. Her parents requested her dog to be placed by her bedside and miraculously, within two days, she was on the road to recovery. This phenomenon has been difficult to explain but has been proven effective many times when the emotional boundaries between man and beast break down.
There are many other ways in which man relies on animals, for instance, clothing and accessories. Animals are a source of nourishment, a business as well as emotional and intellectual entities for man.
Unfortunately, Man has taken animals for granted, destroying wildlife and exploiting it unnecessarily for his own selfish reasons. No matter what the animal: carnivore, herbivore or omnivore, they all play a crucial role, directly or indirectly in the existence of man and this aspect of animals has to be understood before man can live blissfully in a symbiotic relationship with them.
Content: 24/30, Language = 16/20, Total = 40/50 (A1).
Well done. Quite the best I have read on this topic. It is mature and sophisticated in tone - even though it covers predictable areas.
resource : http://schools.moe.edu.sg/rjc/subjects/english/gp/downloads/misc-animals.htm
Ever since the dawn of time man and animals have co-existed in the same environment. Scientifically, man himself is classified as an animal with similar needs. Although animals have killed man and man has hunted animals alike, theirs is a symbiotic relationship which cannot be refuted whatever age or time.
In Charles Darwin's theory of evolution, the existence of a conducive eco-system is highly dependent on the interaction between man and beast.
Different types of animals occupy various strata in the food chain of which man is invariably a part. Man relies on animals for food. Most people eat chicken, beef, mutton and pork as well as eggs and milk.
The very existence of man and the nourishment he needs from the time he is a baby comes mostly from animals.
Vegetarians and vegans have argued that they do not rely on animals for food. This is a false assumption as the vegetables and plants that feed the people are highly dependent on animals. In the wild, the animals eat the plants; if no animals ate the plants, there would be an overcrowding of weeds which would lead to the unhealthy development of plant life, resulting in an imbalance in the eco-system.
Animals also help in dispersing the seeds of fruits and vegetables in excretion. This helps to ensure that there is a continuity in the abundance of plant life. The circle of life is held in place by the animals, ie. the animals eat the plants, the animals help the plants reproduce and man eats both the animal and the plant. The faeces of the animals also help in the growth of the plants. When animals die, their decaying bodies also provide nourishment for the plants which in turn nourish the human beings. In vegetable farms, most organic fertilizers also come from decaying animal and plant matter.
Besides food, man also relies on animals for his livelihood. This can be analysed in two ways: indirectly and directly. Agriculturally based countries such as Australia and Argentina rely on some animals to get rid of other animals which might harm their crops. For instance, following the agriculture downturn in Argentina, state authorities released hundreds of foxes to kill the rabbits which were devouring agricultural produce in the field itself and causing great losses to the farmers.
Farmers also use animals, eg. oxen, to plow their land.
More directly, many people use animals as a means of living.
In India hundreds of thousands of people train animals to perform on the streets. Monkeys, cobras and donkeys provide a source of income for their owners and entertainment for the public. The circus works on this concept. Which circus will thrive without the wonderful pantheon of animals? The zoo and the Night Safari also use animals to entertain as well to collect revenue from the tourist industry to pump into the economy. Policemen also use animals like dogs for sniffing out drugs or carrying out search and rescue.
Animals are also crucial in the education of mankind. Medical students often use animals in the laboratory sessions to effectively understand concepts of anatomy. In scientific research, animals are used as guinea pigs to test a product before it is used on humans.
This has often been labelled the exploitation of animals but the importance of using animals to test new products is undeniable. Although human life is placed above that of animals, the necessity of animals to ensure certain aspects of safety for man is critical.
The social standing of man in some ways can be gauged from animals.
If a man has two oxen in India, he is given due respect and if he were to lose the oxen, it would be akin to losing his honour. In the olden days, even today, the possession of horses was considered a great achievement. In medieval France, if a man were to lose his horse due to sheer carelessness, he would often mete out severe punishment upon himself. Using animals to gauge social status might seem frivolous and flippant on the surface, but it has been practised for thousands of years and the importance of animals serving this function will continue in strong focus.
Animals also help develop the emotional and psychological well-being of people. Many people who keep pets such as dogs develop a strong emotional bonding with the animals. They tend to embrace qualities such as sensitivity and loyalty. Of course this is not true with some people who are prone to violent behaviour around animals but studies have shown that most people who have pets around them tend to be gentler, kinder and more loyal. They also develop a sense of responsibility. Children who have pets grow up, often taking these characteristics with them.
Animals also have a therepeutic quality which makes them good healers together with medicine. Some years ago, a girl in Ohio was suffering from high fever with no sign of recovering. Her parents requested her dog to be placed by her bedside and miraculously, within two days, she was on the road to recovery. This phenomenon has been difficult to explain but has been proven effective many times when the emotional boundaries between man and beast break down.
There are many other ways in which man relies on animals, for instance, clothing and accessories. Animals are a source of nourishment, a business as well as emotional and intellectual entities for man.
Unfortunately, Man has taken animals for granted, destroying wildlife and exploiting it unnecessarily for his own selfish reasons. No matter what the animal: carnivore, herbivore or omnivore, they all play a crucial role, directly or indirectly in the existence of man and this aspect of animals has to be understood before man can live blissfully in a symbiotic relationship with them.
Content: 24/30, Language = 16/20, Total = 40/50 (A1).
Well done. Quite the best I have read on this topic. It is mature and sophisticated in tone - even though it covers predictable areas.
resource : http://schools.moe.edu.sg/rjc/subjects/english/gp/downloads/misc-animals.htm
Sunday, 15 June 2008
How to Play String Instrument using Physic terms
How to play a string instrument using physics terms?
Homework question please help!
Describe the physical process that occurs as your instrument is played and produces sound. Begin with force and finish with detection by the human ear. Include types of waves produced and any and all technical (physics) terms possible. Extra points may be given for terms from 1st semester. (pressure, force, newtons laws)
Answer
You pluck or pull or bang on a string that is stretched between two fixed points. Because it's fixed at two points, that limits the wavelengths that are possible--the endpoints have to be nodes of the wave, so the wavelength must be 2, 2/3, 2/5, 2/7, 2/9, etc times the length of the string. These are the harmonics of the string.
Waves on a string travel at a fixed speed--the square root of tension over density. So if you know the speed and the harmonic wavelengths, you know the harmonic frequencies.
So when you deform the string, it will vibrate with all its harmonic frequencies. The ratio of the frequencies depends on the shape of the deformation. You could use Fourier analysis to figure this out. If you create a sharp deformation by plucking the string, you get a lot of the higher harmonics, so the sound is very twangy. If you strum it gently, you get mostly the principal frequency and the sound is smoother.
The sound is produced when the vibrating string bangs into the surrounding air and causes pressure disturbances. These pressure disturbances propagate into the surrounding air (which is what sound is).
If you want more basic physics on how a wave propagates through a string, read this wiki:
http://en.wikipedia.org/wiki/Vibrating_string
basics of sound:
http://en.wikipedia.org/wiki/Sound#Physi...
Homework question please help!
Describe the physical process that occurs as your instrument is played and produces sound. Begin with force and finish with detection by the human ear. Include types of waves produced and any and all technical (physics) terms possible. Extra points may be given for terms from 1st semester. (pressure, force, newtons laws)
Answer
You pluck or pull or bang on a string that is stretched between two fixed points. Because it's fixed at two points, that limits the wavelengths that are possible--the endpoints have to be nodes of the wave, so the wavelength must be 2, 2/3, 2/5, 2/7, 2/9, etc times the length of the string. These are the harmonics of the string.
Waves on a string travel at a fixed speed--the square root of tension over density. So if you know the speed and the harmonic wavelengths, you know the harmonic frequencies.
So when you deform the string, it will vibrate with all its harmonic frequencies. The ratio of the frequencies depends on the shape of the deformation. You could use Fourier analysis to figure this out. If you create a sharp deformation by plucking the string, you get a lot of the higher harmonics, so the sound is very twangy. If you strum it gently, you get mostly the principal frequency and the sound is smoother.
The sound is produced when the vibrating string bangs into the surrounding air and causes pressure disturbances. These pressure disturbances propagate into the surrounding air (which is what sound is).
If you want more basic physics on how a wave propagates through a string, read this wiki:
http://en.wikipedia.org/wiki/Vibrating_string
basics of sound:
http://en.wikipedia.org/wiki/Sound#Physi...
Hydrophonics System : Continuous Flow Systems
Continuous Flow Systems
Most commercial hydroponic systems direct a continuous flow of nutrient solution over the plant roots. One continuous flow system uses polyvinyl chloride (PVC) pipe of the type commonly used for household waste plumbing. A 2-inch pipe for lettuce or a 4- to 6-inch pipe for tomatoes may be set up with a slight gradient to allow for flow of the solution. Holes of 1- to 1 1/2-inch diameter are drilled in the pipe, and the plants are inserted into the holes. Lettuce plants will support themselves if they have been started in growing cubes. Tomato plants must be supported with wire or string.
The nutrient solution is held in a large tank and pumped or allowed to flow by gravity to the growing pipes. The continuously flowing nutrient solution bathes the roots and then returns to the holding tank. The solution aerates itself as it flows back into the tank.
Major problems with using PVC pipe are its relatively high initial cost and the need for cleaning. After a crop has been grown in the pipe, it should be thoroughly cleaned with a 0.5 to 1.0 percent sodium hypochlorite solution (made by mixing one part of household bleach with nine parts of water) to prevent contamination from disease organisms.
With the nutrient film technique (NFT) the same methods but less expensive materials are used. A flexible plastic tube supported by a wooden tray is used in place of rigid PVC pipe. The tube is made of black plastic film (much like the plastic film mulch use for gardens) with holes punched at specified intervals. The plants are started in root cubes and then placed in the tube where they are bathed in a continuous flow of nutrient solution.
A variation of the continuous flow system is marketed as the Pipe Dream. This system uses 2-inch corrugated plastic drainage pipe placed vertically in a 6-inch drainage pipe for tomatoes or a 2-inch pipe for lettuce (Figure 8). A plastic mesh tube filled with peat moss is placed in the vertical tube and allowed to hang into the horizontal pipe. A nutrient solution flowing in the horizontal pipe supplies water and fertilizer, which move up into the peat moss and thus to the plant roots. Although seeds can be planted directly in the peat moss, it is best to start with transplants.
Most commercial hydroponic systems direct a continuous flow of nutrient solution over the plant roots. One continuous flow system uses polyvinyl chloride (PVC) pipe of the type commonly used for household waste plumbing. A 2-inch pipe for lettuce or a 4- to 6-inch pipe for tomatoes may be set up with a slight gradient to allow for flow of the solution. Holes of 1- to 1 1/2-inch diameter are drilled in the pipe, and the plants are inserted into the holes. Lettuce plants will support themselves if they have been started in growing cubes. Tomato plants must be supported with wire or string.
The nutrient solution is held in a large tank and pumped or allowed to flow by gravity to the growing pipes. The continuously flowing nutrient solution bathes the roots and then returns to the holding tank. The solution aerates itself as it flows back into the tank.
Major problems with using PVC pipe are its relatively high initial cost and the need for cleaning. After a crop has been grown in the pipe, it should be thoroughly cleaned with a 0.5 to 1.0 percent sodium hypochlorite solution (made by mixing one part of household bleach with nine parts of water) to prevent contamination from disease organisms.
With the nutrient film technique (NFT) the same methods but less expensive materials are used. A flexible plastic tube supported by a wooden tray is used in place of rigid PVC pipe. The tube is made of black plastic film (much like the plastic film mulch use for gardens) with holes punched at specified intervals. The plants are started in root cubes and then placed in the tube where they are bathed in a continuous flow of nutrient solution.
A variation of the continuous flow system is marketed as the Pipe Dream. This system uses 2-inch corrugated plastic drainage pipe placed vertically in a 6-inch drainage pipe for tomatoes or a 2-inch pipe for lettuce (Figure 8). A plastic mesh tube filled with peat moss is placed in the vertical tube and allowed to hang into the horizontal pipe. A nutrient solution flowing in the horizontal pipe supplies water and fertilizer, which move up into the peat moss and thus to the plant roots. Although seeds can be planted directly in the peat moss, it is best to start with transplants.
Hydrophonics System : Aeroponics
Aeroponics
The adventurous hobbyist may wish to try an even more exotic method of growing plants. In the aeroponic system the roots of the plant grow in a closed container. A misting system bathes the roots in a film of nutrient solution and keeps them near 100 percent relative humidity to prevent drying.
The container may be of almost any design as long as it is moisture proof and dark. Tomatoes may be grown in tall, narrow containers lined with plastic. Lettuce and strawberries have been grown in A-frame containers (Figure 7) to make the best use of available space and light.
Position the spray nozzles so that at least a portion of each plant's roots are sprayed directly. You may leave the nozzles on at low pressure continuously or operate them intermittently, on for 20 seconds and off for 40 seconds. A fungicide may be added to the solution to avoid root rot pathogens.
The adventurous hobbyist may wish to try an even more exotic method of growing plants. In the aeroponic system the roots of the plant grow in a closed container. A misting system bathes the roots in a film of nutrient solution and keeps them near 100 percent relative humidity to prevent drying.
The container may be of almost any design as long as it is moisture proof and dark. Tomatoes may be grown in tall, narrow containers lined with plastic. Lettuce and strawberries have been grown in A-frame containers (Figure 7) to make the best use of available space and light.
Position the spray nozzles so that at least a portion of each plant's roots are sprayed directly. You may leave the nozzles on at low pressure continuously or operate them intermittently, on for 20 seconds and off for 40 seconds. A fungicide may be added to the solution to avoid root rot pathogens.
Hydrophonics System : Aggregate Culture
Aggregate Culture
Growing plants in aggregates such as sand or gravel is often preferred to the water culture method since the aggregate helps to support the roots. The aggregate is held in the same type of tank as is used for a water culture system. The nutrient solution is held in a separate tank and pumped into the aggregate tank to moisten the roots as needed. After the aggregate has been flooded it is drained to provide aeration. Enough water and nutrients cling to the aggregate and roots to supply the plant until the next flooding
The solution is generally pumped to within 1 inch of the surface and then allowed to drain. If the top surface of the bed is kept dry, the growth of algae will be minimal. To allow rapid drainage, the aggregate must be coarse. Use sand with particles of at least 1/16-inch diameter or gravel of about 1/4- to 3/8-inch diameter. The best aggregates are silica gravel, granite, basalt, or smooth river-bottom rock of the inert type that contains no calcium. Larger aggregates will require more frequent flooding, whereas smaller aggregates will not drain properly. In small, experimental units you may use any of several different substances. Perlite, Styrofoam, and crushed marbles have all been used successfully by hobbyists.
The aggregate should be flooded for about 10 minutes and allowed to drain for no longer than 30 minutes.
Growing plants in aggregates such as sand or gravel is often preferred to the water culture method since the aggregate helps to support the roots. The aggregate is held in the same type of tank as is used for a water culture system. The nutrient solution is held in a separate tank and pumped into the aggregate tank to moisten the roots as needed. After the aggregate has been flooded it is drained to provide aeration. Enough water and nutrients cling to the aggregate and roots to supply the plant until the next flooding
The solution is generally pumped to within 1 inch of the surface and then allowed to drain. If the top surface of the bed is kept dry, the growth of algae will be minimal. To allow rapid drainage, the aggregate must be coarse. Use sand with particles of at least 1/16-inch diameter or gravel of about 1/4- to 3/8-inch diameter. The best aggregates are silica gravel, granite, basalt, or smooth river-bottom rock of the inert type that contains no calcium. Larger aggregates will require more frequent flooding, whereas smaller aggregates will not drain properly. In small, experimental units you may use any of several different substances. Perlite, Styrofoam, and crushed marbles have all been used successfully by hobbyists.
The aggregate should be flooded for about 10 minutes and allowed to drain for no longer than 30 minutes.
4 Hydrophonics systems
HYDROPONIC SYSTEMS
--------------------------------------------------------------------------------
1.Water Culture or Aquaculture
2.Aggregate Culture
3.Aeroponics
4.Continuous Flow Systems
--------------------------------------------------------------------------------
1. Water Culture or Aquaculture
The water culture method of hydroponics is the simplest to set up on a small scale. In this system the plant roots are totally immersed in a nutrient solution. The major disadvantages of this system are the large amount of water required per plant and the need to aerate the solution continuously.
The actual design of the system is limited only by the imagination of the builder. The system must provide means to (1) support the plant above the solution, (2) aerate the solution, and (3) prevent light from reaching the solution (to prevent the growth of algae).
A standard tray or tank is shown in Figure 1. The tray may be made of concrete or of plastic-lined or asphalt-sealed wood. If you use asphalt to seal the tank, be sure that it does not contain creosote or tars. Do not use asphalt that leaves an oil film on the surface of the water. A typical size is 6 to 12 inches deep, 2 to 3 feet wide, and as long as is convenient. The plants can be supported by inserting them through holes drilled in a plywood top or through holes punched in a l-inch-thick Styrofoam sheet that floats on the surface of the solution.
You can make a small system from a child's wading pool, a plastic pail, a fish tank, or a drinking tumbler. A large tomato plant should be grown in a container that holds at least 2 gallons as the solution in a smaller container will be used up too quickly. Lettuce plants, on the other hand, may be grown in smaller containers.
Short plants such as lettuce and spinach will usually support themselves. Drill a 1-inch hole in the Styrofoam or wooden cover and insert a transplant. The plant may be held in place by packing a flexible material such as cotton into the hole around the stem. A plant started in sand, perlite, or vermiculite can be transplanted easily to the water culture system because these materials can be washed from the roots readily.
Vining plants such as cucumbers and tomatoes must be supported by string. When pruned to a single stem they can be wrapped around a loosely hung string as they grow (Figure 2).
Aerate the solution continuously by pumping air through a perforated hose or pipe immersed in the solution. For small systems an aquarium pump and porous stone will work. Do not bubble the solution too vigorously because excessive movement may damage the tender roots and impair plant growth.
Change the nutrient solution every two weeks when the plants are small and once a week as they begin to mature. Add water daily to keep the solution level constant.
--------------------------------------------------------------------------------
1.Water Culture or Aquaculture
2.Aggregate Culture
3.Aeroponics
4.Continuous Flow Systems
--------------------------------------------------------------------------------
1. Water Culture or Aquaculture
The water culture method of hydroponics is the simplest to set up on a small scale. In this system the plant roots are totally immersed in a nutrient solution. The major disadvantages of this system are the large amount of water required per plant and the need to aerate the solution continuously.
The actual design of the system is limited only by the imagination of the builder. The system must provide means to (1) support the plant above the solution, (2) aerate the solution, and (3) prevent light from reaching the solution (to prevent the growth of algae).
A standard tray or tank is shown in Figure 1. The tray may be made of concrete or of plastic-lined or asphalt-sealed wood. If you use asphalt to seal the tank, be sure that it does not contain creosote or tars. Do not use asphalt that leaves an oil film on the surface of the water. A typical size is 6 to 12 inches deep, 2 to 3 feet wide, and as long as is convenient. The plants can be supported by inserting them through holes drilled in a plywood top or through holes punched in a l-inch-thick Styrofoam sheet that floats on the surface of the solution.
You can make a small system from a child's wading pool, a plastic pail, a fish tank, or a drinking tumbler. A large tomato plant should be grown in a container that holds at least 2 gallons as the solution in a smaller container will be used up too quickly. Lettuce plants, on the other hand, may be grown in smaller containers.
Short plants such as lettuce and spinach will usually support themselves. Drill a 1-inch hole in the Styrofoam or wooden cover and insert a transplant. The plant may be held in place by packing a flexible material such as cotton into the hole around the stem. A plant started in sand, perlite, or vermiculite can be transplanted easily to the water culture system because these materials can be washed from the roots readily.
Vining plants such as cucumbers and tomatoes must be supported by string. When pruned to a single stem they can be wrapped around a loosely hung string as they grow (Figure 2).
Aerate the solution continuously by pumping air through a perforated hose or pipe immersed in the solution. For small systems an aquarium pump and porous stone will work. Do not bubble the solution too vigorously because excessive movement may damage the tender roots and impair plant growth.
Change the nutrient solution every two weeks when the plants are small and once a week as they begin to mature. Add water daily to keep the solution level constant.
What is hydrophonics?
Hydroponics from the Greek 'water working', is simply growing plants without soil. (Hydro=water and Ponic=working)
Hydroponics may also be called 'controlled environmental agriculture'.
In a complete controlled environmental agriculture system you control:
light, temperature, water, CO2, oxygen, pH and nutrients
A Hydroponic Garden is low maintenance and efficient. Every other day a pH check is done and water level topped up. Nutrient is changed every 7 - 12 days. A timer is recommended to automatically turn the light and garden on and off.
Tips Propagating Seeds
optimum temperature 75 degree F to 85 degrees F
optimum humidity 80% to 90% Relative
remove humidity tent daily
24 hours light until first true leaves appear
then remove humidity tent, 18 hours of light/day
use only diluted nutrient on seedlings
seed soak-foliar feed-Superthrive BI harden -off, increases light and nutrient levels gradually
foliar feed nitrozyme for 3-5 day harden off period
bolting-increase light intensity and/or ventilation
yellow leaves-increase vegetative nutrient strength
Tips Propagating Stem Cuttings
use 6" humidity dome
18 hours light/day
rooting hormones-Wilson roots, Stim Roots, Willow water
remove largest leaves to avoid wilting
remove tent permanently after 10 days
damping off fungi-better air circulation,and/or treat with damp off
browning leaf tips-to much nutrient.
Thursday, 12 June 2008
In my opinion ...
Hello..listen..the future leader is speaking ...ehem..listen to his opinion shhhh..
Opss...cut..cut camera cut
This is one of the activities done in English Language Class. They did perfectly well before the shot was taken. But, oh well..they were just camera shy he he he. Anyway, what an act...bravo..bravo.
Tuesday, 10 June 2008
Monday, 9 June 2008
The Amazing Twins
A mixed-race British mom gave birth to twins recently
one of each.
No, not a boy and a girl.
Two girls - one black, the other white.
The odds of such a birth are about a million to one,
experts said .
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