what is rain water harvesting?
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it means collectin rain water in big tanks and using it 4 future purpose.it is mainly done in water scarity places.in some places that has heavy rain collects it and use it in whole summer season.it is used to water plants ad 4 bathing and washing.these water can also be used as drinking water after purifying  it.special methods such as constructing rain tanks,using filters are used 4 that.
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you can separate water into its constituents by passing electricity through it
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Water which can be used to irrigate fields and genrate electricity if dammed up.
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dams aim to receipt the surplus water at the rainy seasom so it's water can utilize at dry season. The utilizing to change the natural distribution water to demand condition. And other used such as generating a generator to produce electric.\n\nBArrages created just to boosting up the water level or face irrigate so the water can irrigating the longest place that we designed.
708032
The Mekong River and the annual monsoon rains I would have thought.\nThey are beneficial as all water resources are in irrigation and Industry, especially in that region of  the flooding of rice paddys.\nI know in S.E. Asia they have up to three rice crops harvested every year. Vietnam used to be called the rice bowl of Asia.
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efficient use of under ground water\n\nEngineering Practices\nWater Reuse and Recycling\n\nLand irrigation methods\nInstall irrigation devices that are the most water efficient for each use. Micro and drip irrigation and soaker hoses are examples of water efficient irrigation methods.\n\nPlant it smart. Xeriscape landscaping is a great way to design, install and maintain both your plants and irrigation system. More importantly, it will save time, money and water.\n\nLeakage/Loss Control
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Rain water but not acid rain water.  Since I don't get a lot of rain in my state I usually used purified water mixed with miracle grow.  If you want your plant to grow faster make sure you give it enough light as well.
254960
It's a chemical reaction between the materials used in country roads and natural raindrops.  The drops gather together (congeal) and become frogs.  Where I grew up it was suburban city concrete sidewalks and worms.
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The gravel is to keep the dust down and to allow for better drainage when it rains.  As you are probably aware the region is extremely dry most of the year but when the rain comes the ground is unable to absorb the water and forms huge puddles.  The gravel helps cut down on this water and some of the damage it can do if it is left to sit (think electrical and health hazards).
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step 1: place a bunch of buckets around your school\nstep 2: after a rainy day collect all the water from the buckets.\nstep3: boil the water to kill all the bacteria in it.
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No. It is a chemical compound. All rain water is a compound of two elements hydrogen and oxygen. The chemical formula for water is h2o - meaning two hydrogen atoms and one oxygen. Usually when rain becomes acid it has sulfur dioxide (another compound formed of sulfur and oxygen) and nitrogen oxide (yet another compound formed from the combination of the elements nitrogen and oxygen as well). These chemicals combine with the water to form sulphuric acid and nitric acid.
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food, water and shelter
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Because when people build dams or change the structure of a water way it disrupts the delicate balance that is required to support fish and other wild life. Dredging is a procedure used to remove large deposits of debris that collect at the bottom of rivers and streams after they have been changed.
557230
to maximize surface area for the collection of sunlight and minimize weight and material used. also, yes it helps transport water and nutrients.
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There are currently NGO's  doing just that. The problem in the developing nations is the corruption in all areas of government. As volunteers or paid employee's the task can become daunting as technology introduced into these villages that seems antique by our standards is modern to them. Teaching modern farming techniques like rotating crops and good agriculture management empowers the local farmers and improves yield. It is a time consuming venture and water management pratices are very important when well water is the only source. You have a good idea, work with it and have fun.
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The shape of a drop of rain is constrained by the surface tension, which tries to give it the shape for which the surface area is minimum. For a given volume, the spherical shape has the minimum surface area. That is why rain drops acquire spherical shape.
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Not really. BUT, through cloud seeding we are now reducing the damage that hail stones cause to crops. if there were a way to do this so tha rain fell in a different place then the application could be used as a tool by the military. they could force drought on areas that rely on rain for their economy or cause flooding in areas that already  receive sufficient rain-fall. the technology exists but is not really practical as the scale of an operation would be prohibitive (not to mention that doing these things would take time and the military likes quick and clean operations. (unlike Iraq)