Princípios da Agroecologia

Agricultura sustentável tem que considerar aspectos socioeconômicos e culturais dos grupos sociais implicados. Não basta proteger e melhorar o solo ou a produtividade agrícola se não resulta em melhorias nas condições de vida das pessoas envolvidas. Portanto, agricultura sustentável é um conceito que implica aspectos políticos e ideológicos que tem a ver com o conceito de cidadania e libertação dos esquemas de dominação impostos por setores de nossa própria sociedade e por interesses econômicos de grandes grupos, de modo que não se pode abordar o tema reduzindo outra vez as questões técnicas.

Francisco Roberto Caporal

http://www.aba-agroecologia.org.br/

grãos

"Muita gente pequena, em muitos lugares pequenos, fazendo coisas pequenas, mudarão a face da Terra". provérbio africano

Como os lobos mudam rios

Como se processa os animais que comemos

Rio Banabuiu

https://youtu.be/395C33LYzOg

A VERDADE SOBRE O CANCER

https://go.thetruthaboutcancer.com/?ref=3b668440-7278-4130-8d3c-d3e9f17568c8

quinta-feira, 18 de outubro de 2012

Preparing Our Children For a Resilient Future,

Preparing Our Children For a Resilient Future, Part III: Water

Biodiversity, Biological Cleaning, Conservation, Consumerism, Deforestation, Education, Global Warming/Climate Change, Health & Disease, Potable Water, Regional Water Cycle, Soil Erosion & Contamination, Storm Water, Village Development, Waste Water, Water Contaminaton & Loss, Water Harvesting — by Anthea Hudson October 18, 2012

Water — without it life on earth could not exist and yet it is often treated with little care or respect, especially by more affluent communities. Clean drinking water is actually a valuable and diminishing resource, due to all the toxins that are carelessly allowed to make their way into our water systems.
These statistics about water may surprise you and give you a greater understanding about just how important it is that we protect water, especially our potable water.
75% of the Earth’s surface is covered with water — however 97% of that water is the salt water of our oceans. That only leaves 3%, but 2% of that is frozen and only 0.5% is actually usable fresh water! Just 0.5% of all the water on Earth. Kinda brings the point home, doesn’t it?
As you can probably see, it is therefore vital that we help our children understand the value of water, the importance of protecting it and ways in which they can use it more sustainably.
Below are some ideas for introducing these concepts to your children… some of them quite a bit of fun, but with very important messages behind them.

Where Does Your Water Come From?
Do you know where the water your family uses comes from? Is it collected in a huge dam? Piped from a river? Turned into fresh water from sea water using a desalination plant? Or do you harvest your own water from rain water tanks, property dams, springs, bores and wells?
If your family is responsible for providing all of its own water, then you will probably have a good idea of how important it is to keep that water source in good condition and not to waste water. If, however, you get water from a public source, such as a huge dam or river, then you may not think very much about it. You turn on a tap, and — hey presto — out it comes, whenever you want it. But that doesn’t mean it’s actually a limitless resource or that we should waste it or neglect its care.
Below are some questions to think about in researching the path of your water — from raindrop to tap.
  • Where does water start? Learn about cloud formation. What different types are there and which ones are more likely to result in rain? What can affect how and where clouds form?
  • How does the water flow on the ground to the dam or river that you obtain your water from? Is it runoff from winter snows? It is the result of the joining of many small creeks etc., that meet and create larger and larger flows, until a big river is formed? Where do these flows originate? Where do they end? A lake? Out to sea? What do they pass through along the way that can affect the water quality?
  • If your water ends up in a reservoir, where is it? When was it built, and what was there before? How much water does it hold and what capacity is it currently at? Has the water quantity been higher or lower this year than usual? What about the past decade? If the dam becomes full, how is the overflow dealt with? How is the water treated as it leaves the dam, or anywhere else along the way, before it reaches your home?
  • What about desalination plants? How do they work? How complex and expensive is the process compared to other methods of water harvest? What difficulties have to be dealt with? How much energy is used?
  • Wherever your water is from, how does it travel from its source (dam, river) to your home? Where does it have to travel and how far? What difficulties might have had to be overcome to get the water across this area?
  • With underground water sources, such as bores, wells and springs, how did the water get there originally? In what kind of areas could you expect to find ground water that’s reasonably accessible? What problems might have to be dealt with when harvesting ground water? How is the water brought from underground to the holding tank? Windmill? Well? How can we try to limit the amount of pollutants that may contaminate it? What might happen if the groundwater is allowed to be overused? What quality is the groundwater in your area and what treatment might it need to make it useable? Is it drinking quality water, or really only suitable for gardens and other household use?
  • How is rain water harvested? How does it get from where it falls to the tank… and then to the house or wherever it is being used? What problems may need to be overcome? What considerations might be necessary to maintain its good quality?
  • Once you know where your water comes from, consider taking a day trip (or longer) to follow the path of your water. Track down the river or dam and visit them… Backtrack the source for as long as you like. If there’s a desalination plant, visit the ocean in the area and see if you can visit the plant, or at least get a look at it from outside. What can you learn and discover about your water by actually seeing its progression in person?
Solar Still
For another fun way to collect water, try making your own solar still. This involves digging a hole in the ground, in a sunny location, into which you place some plant material — ideally succulents. A jug or bowl is placed in the centre, as your water collector. The hole is then covered with a sheet of plastic, secured with stones, with a small stone in the centre, causing the plastic to dip down over the jug.
The sun then causes water to be evaporated from the plant material, which then condenses on the plastic and drips down into the jug. You can then drink or otherwise use the collected water!
Just to be safe, use non-toxic plants for this activity.
How Much Water Falls?
Do you know how much rainfall your area gets? Do you think it’s high or low compared to other parts of the country? Have a look at rainfall statistics for your area and compare to other areas.
What about different times of the year — do you get more or less in summer or winter? How does this compare with other areas? Pay special attention to the differences in the times which have higher rainfall between tropical areas and non-tropical. What do you notice?
How does recent rainfall compare with falls a decade ago? A century? Why do you think this might be?
Make a Rain Gauge
You can make a simple rain gauge at home, using a large soft drink or water bottle, and use it to keep track of how much rain falls where you live.
Cut the top ¼ off the bottle, then put it upside down into the remaining part of the bottle. Use some tape to hold it in place, so that it can’t slip or blow out of position.
You can then mark increments (such as millimetres and centimetres) either on the side of the bottle, or onto a piece of card or paper, using a ruler and a marker, and sticking it onto the side of the bottle.
Place the bottle in a spot where it has nothing above it, or too close, to interfere with the water collection.
To avoid it getting tipped or blown over, you can either half bury it in a pot or the ground, or wedge it between a couple of large rocks. Make sure they don’t go too high though and stop any of the rain from reaching the bottle.
At a set time each day, check the measurement of your rainfall and record it. Tip out the collected water and reposition the bottle, ready for the next rainfall. If you wish, you could choose to record it once a week instead of every day; however you may lose a little more due to evaporation, so records won’t be as precise.
This activity could be continued throughout the year, or even longer and comparisons made on your own collected data. If your family is enthusiastic, this project could be undertaken for several years, creating quite a comprehensive set of data for your location.
How Much Water Does Your Household Use?
Carry out your own household water audit. Get your children to work out ways they could measure approximately how much water each household activity uses. Some ways may be: referring to appliance and fixture manuals; timing how long a tap or shower takes to fill a certain size container and working out usage amount from how long it is run each time; or scooping out and measuring after use.
Try to include all water usage, such as:
  • Washing clothes
  • Washing dishes
  • Showers, baths, personal washing, brushing teeth, etc.
  • Animal use
  • Garden and outdoor use
  • Cooking
  • Drinking
So, what was the approximate total of water used daily?
How much do you pay for water per kilolitre and therefore, how much would this amount of water cost?
Is cost the only factor you should be considering, or are there other, possibly more important factors?
Walking for Water
Here’s an activity to show children one of the factors that plays an important part for many people around the world.
How far do you have to go to collect your water? Just to the nearest tap? For many people, the walk to collect their water can be many kilometres! Let’s see how you go doing that.
Get two buckets… and a partner if you can. This cuts the work in half. If not, you will have to manage by yourself. Make sure you know how much your bucket holds — or, more importantly, how much you can manage to carry without spilling any.
Now work out how many bucket loads of water your daily use audit amount would take. Rather a lot, I expect?
Your job is to collect your water from the ‘well’. Decide how far away your well is. Maybe it’s 100 metres… or 500 metres, or even further. Work out where you will need to walk to cover the decided distance. You could decide to walk along the footpath, or do this activity in a park or on a sports oval.
Place a bucket with the planned amount of water in at one end, and the empty bucket at the other. You begin at one end, and your partner at the other.
You each then walk to the other end. Whoever is carrying the bucket with water must be careful not to spill any. Once you reach the other end, you put your bucket down, and pick up the other one… and repeat as many times as it takes to collect your daily amount of water. The full and empty buckets represent walking to the well with an empty one, then back, after filling it.
If you are doing this activity alone, you could just carry the empty bucket back and forth the required number of times, then repeat with the full bucket, or swap buckets for a while as you go.
Did you manage to collect all of your water? Are you tired? If not, extend the distance to your well and try again! And remember, you would have to do this every single day if you were to keep providing the amount of water you currently use. What about carrying the bucket on your head, like many people do — can you manage this without spilling any? How easy is it?
After this activity, do you have a greater respect for the value of water to many people? Do you think you would continue to use as much water as you do now, if you lived in a community which had to collect its water by hand? How might you have to reduce the amount of water you use? What uses are vital and what might you decide to give up, or lessen? (Remember — in many of those communities, if you don’t water your gardens or animals, you don’t have any food to eat!)
What changes could you make right now, in your home, to lessen the water that you use?
How much do you think residential demand for water has changed over time in your area? Can you find any statistics to confirm this? What about agricultural water usage — is it higher or lower? Why? How about factories and other industrial uses — how does this compare now to past times?
Research water use in other countries — which country uses the most and which uses the least? Does the variation surprise you? What do you think might have an effect on how much water a community uses? Where does your country fall in the water usage list? How does your family’s use compare to the national average? Do you think it is fair that some people can easily have so much water and others must struggle to even have a small amount?
How Can We Create More Sustainable Water Practices?
Water Usage
Using less is obviously one of the important ways in which we can lessen our impact on water. What things can you implement in your home to use less water?
Ideas that cost little or nothing:
  • Fix dripping taps, etc.
  • Limit shower time.
  • Showers usually use less water than baths.
  • Where appropriate, shower or bathe together, or re-use bath water for more than one person.
  • Don’t run water continuously while brushing your teeth or washing hands.
  • Don’t wash dishes under a running tap.
  • Save water when getting shower up to temperature, by sitting a bucket under it, then use the water on the garden or for household uses.
  • Bucket out the bath and use on garden.
  • Mulch garden well.
  • Water at ideal times and for the needs of the plants.
Ideas that do cost, but will save water — and money — long term:
  • Install low flow shower heads.
  • Install a dual flush toilet.
  • Install a grey water system.
  • Wash full loads of clothes or dishes — don’t just run for a few things. Choose a small load option if you have one and want to run it for a small load.
  • When replacing washing machines and dishwashers, choose low water usage and small load option models.
  • Dishwashers can often use less than hand washing dishes.
  • Design and plant a low water needs garden.
Catching Water
Catching water that would otherwise just run off is a good way to get extra water. Rain water tanks are ideal; however, barrels, large containers, etc., can adequately catch water for use on the garden.
Roof evaporative air conditioner run-off outlets can have a hose attached, with water run down off the roof and into garden areas.
Makeshift collectors for gutter drain pipes can be made out of cut-off milk or juice bottles, taped to the outlet, with grey water hoses attached, which can then be run to the garden.
What Affects Water Quality?
There are lots of things that affect the quality of our water… most of the detrimental effects are caused by humans! They include things such as pesticides, herbicides, runoff from factory farms, factories, industry, oils spills, chemical spills and litter.
Let’s have a closer look at some of the things that endanger the health of our rivers… and the water we use.
Follow the River’s Journey
Kids love this fun interactive activity! It helps show them, in a hands-on way, what happens to our rivers as they travel across the country and the kinds of pollution we need to be aware of and concerned about. It can be done just as a family activity, or a group — we had fun doing it for our home-schooling group and also my son’s scout troop.
Gather around your ‘river’, preferably with easy access to the water for all involved. Read the story below to the children and have them add the ‘pollutants’ as the story requires. ‘Fish, boats and waves’ are then used to create a natural mixing of the water and pollutants.
The Equipment:
  • A container for your ‘river’, such as a children’s clam shell, blow up toddler pool; or a large plastic container or aquarium if you only have a small group.
  • Cut-out plastic fish, boats or waves can be made, stuck on sticks, and then used to mix the water, as real fish, boats and waves would do.
The ‘Pollutants’:
  • Litter (can be the same basic composition for each lot) — lolly wrappers, can ring pulls, paper scraps, ice cream sticks, etc.
  • Sawdust — if possible, obtain real sawdust. Alternatively you could use bran or similar.
  • Soil — use real soil.
  • Piggery Sludge — thin gravy with a little green colouring
  • Barrel Chemicals — bicarbonate of soda and vinegar, mixed immediately before adding. Add food colouring, if you wish. (Warning: this will foam up, so should be mixed over the water.)
  • Mud — make real mud or gravy.
  • Cow Manure — formed brown play doh or sultanas.
  • Tannery Chemicals — vinegar or water with red food colouring.
  • Fertiliser and Pesticide (can be same for each time) — bicarbonate of soda, or cornflour, or flour.
  • Sewage — water with yellow food colouring, sultanas and toilet paper scraps.
  • Boat oil — car sump oil, or used (brownish) vegetable oil.
  • Sink Scraps — find coleslaw mix or other fine food scraps.
  • Shampoo — shampoo mixed with water and shaken up.
  • Sheep Manure — same as cow manure.
  • Factory Effluent — water with dish detergent and green food colouring, shaken up.
  • Dog Poo — same as other manures.
  • Quarry Sand and Gravel — sand and gravel.
  • Soil and Rubble — soil and rubble.
  • Supermarket Litter — plastic bags, packaging, cigarette butts, etc.
  • Lawn Clippings — lawn clippings or finely chopped green paper.
  • Fishing Line — fishing line scraps, also hooks and sinkers if desired.
  • Salt
  • Algae — dark green powder paint or spirulina/wheatgrass powder.
The Story
The journey of our river starts high up in the mountains, as snow begins to melt when the warmer weather arrives. Melted snow trickles down the steep slopes, joining with other rivulets as it goes. This happens all over the mountain area, forming small creeks as the volume grows. Springs also gush with clear water and join the creeks. As the water travels across the land, creeks join up and eventually the flowing water becomes big enough to be called a river. This river will flow many kilometres as it makes its way to the sea, passing through all sorts of countryside. What does it encounter? What do people do with, and in it? Let’s follow its path and see!
In the beginning the water is clear and pure, travelling through isolated wild areas, rushing, gurgling along, tumbling over rocks.
As it makes its way down the slopes, it passes a ski resort, now closed for the season, where skiers have carelessly littered the area while skiing. Some of this litter is caught up in the water and carried along. (Add litter.)
A logging operation and sawmill are located on the lower slopes. Sawdust from the sawmill drifts into the river on the breeze. (Add sawdust.)
The cutting down of so many trees causes erosion of the river banks, causing soil to be washed into the flow of water. (Add soil.)
A large smelly piggery is round the bend. The effluent ponds for their waste is located too close to the river, and is not large enough for all they produce, so revolting stinky sludge often overflows into the water. (Add piggery sludge.)
A pretty spot, downriver a few kilometres, is ruined by the old rusty leaking barrels of chemicals dumped on the river bank. Toxic frothy chemicals seep down into the water. (Add barrel chemicals.)
As the river winds down into the valley, we travel through a large cattle station. Cows’ hooves dig up the earth on the banks as they drink. This makes the banks unstable and mud often slides into the water. (Add mud.)
They also poo as they eat and their manure also drops into the river. (Add cow manure.)
There’s a tannery not far away, where nasty chemicals are disposed of illegally, straight into the river. (Add tannery chemicals.)
Wheat is also grown in this area and the fertiliser and pesticides often end up in the river, especially after rain or during careless application. (Add fertiliser and pesticide.)
A few kilometres downstream is a picturesque campground. Unfortunately, visitors are careless with their litter and it blows into the river. (Add litter.)
Someone camping here is very thoughtless and empties their portable toilet directly into the river, rather than disposing of it in the proper place. Yuck!!! (Add sewage.)
Many visitors also bring their ski boats, which often leak oil into the water. (Add oil.)
It’s a popular stretch of river and many houseboats motor past with happy holiday makers. Water from their kitchen sinks run out into the river, carrying with it grease and food scraps. (Add sink scraps.)
People showering on the boats also release shampoo, soaps and other chemicals into the water. (Add shampoo.)
Orchards line the river for the next few kilometres. Once again, fertilisers and pesticides often drift or wash down to the water. (Add fertiliser and pesticide.)
Next we wind through a sheep station. Attracted by the river water, sheep frequent the banks often, leaving lots of manure that slips into the water. (Add sheep manure.)
Around a few more bends the peaceful rural scene is disturbed by factories, spewing toxic fumes into the air. Some also illegally empty their waste chemicals directly into the river. (Add factory effluent.)
Too close for comfort we come upon a picnic area, where children frolic in the shallow water. Of course, where there are picnics there is often litter, and this spot is no exception. Wrappers, plastic wrap and other refuse blows into the river. (Add litter.)
People also love to bring their dogs along for the fun, but they don’t always pick up what their dogs ‘leave behind’ and the poo often ends up in the water. (Add dog poo.)
The magnificent cliffs on the other side are spoiled by quarrying. Sand and gravel from the operations end up in the river. (Add sand and gravel.)
The quarry is working to supply the new housing development which is in the process of being built, just down the river. Builder’s rubble and disturbed soil make their way into the water. (Add soil and rubble.)
The new development already boasts a fully operational shopping centre. Unfortunately, litter from shoppers such as plastic bags, wrappings, cigarette butts, etc., end up in the river. (Add supermarket litter.)
To keep everything looking ship shape the extensive lawns around the shopping centre and nearby river bank parks are mowed regularly and lawn clippings blow into the river. (Add lawn clippings.)
Fishing has been a popular pastime on the river banks (although less so now, as for some reason the fish seem to be dying. I wonder why…?), but when lines break, hooks, sinkers and fishing line ends up in the river. (Add fishing line, etc.)
There are discussions about building a dam upstream a bit to help supply water to the new community, but because of its high pollution level, there are concerns over the quality and the expense and practicality of making it drinkable.
High salinity is also a worry, as so much of the water has been removed and used by people upstream. (Add salt.)
The algal bloom appearing in this area is also very concerning. (Add algae.)
The river soon makes its way into the nearby sea, taking with it all it has collected along the way. People grumble about the smell of the river water and how dirty and littered their beach is….
I bet you could tell them the reasons why!
Here are a few things to think about:
  • How would you feel about swimming or washing in this water? What about drinking it?
  • How many of these episodes of pollution do you think are illegal? Should they be? What sort of punishments do you think people who pollute our rivers should get?
  • How do you feel about the problems facing our rivers today and what do you think could be done to help? What could you do?
Salinity
As mentioned in the above story, taking too much water from our rivers increases the salinity of the water that is left. This can cause great problems, both for ecosystems (as has been happening in the Lower Murray and Coorong areas in South Australia) and for us in the water we use in our homes and gardens.
The following activity helps children discover the effects of varying degrees of salinity on plant growth.
The Equipment:
  • At least half a dozen small pots to grow your plants in — more if you wish. You can use plant pots or containers such as yoghurt or ice cream tubs, or even cut down milk or juice cartons. You will need to make some holes in the bottom for drainage.
  • Small stones or gravel to increase good drainage in bottom of pot.
  • Garden soil or potting mix.
  • Seeds, such as wheat or beans or something else easy to grow.
  • Water.
  • Salt.
  • Container and spoon to mix water and salt solutions.
  • A warm, light area to grow the plants, protected from pests.
The Experiment:
  • Place some stones or gravel in the base of your pot. Top up with the soil/potting mix until about 3 cm from the top of the pot.
  • Using the depth recommended for your specific type of seed, push 2 or 3 seeds down into the soil in each pot. Push the soil back over the seed and firm down.
  • Water the first pot with plain water. Measure the amount you use, so that you can give the other plants the same amount of their water. Water carefully, so as not to disturb the seed. This plant will be your control sample, which will show you how the plants grow normally, with plain water. You can then compare the differences you observe in plants with increasing salinity in their water.
  • Make batches of water with varying salinity. The change of degree in each will depend on the number of plants you are growing. Begin with barely salty water, right up to saltier than sea water, with equally increasing amounts per batch. Water each plant with one of these mixes — the same amount as the first plant.
  • Record how much salt you added to each solution so that you can replicate it over the course of the experiment, and have it to refer to when you finalise your results. Also, make sure you know which plant is receiving which salinity.
  • Carefully water each pot, with the same amount of its water, as often as required. Keep moist, but not soggy.
  • Record what you notice as the plants appear and grow — or don’t. Photos at various stages are a good idea too to help track their progress.
Consider these questions:
  • What do you notice during the first few days after they appear?
  • What happens after a while?
  • Can you theorise what is happening and why?
  • Can you relate your experiment to real world situations and problems?
  • What could be done to help solve these problems?
  • Are any of these being done?
If you want to do more, you could repeat the test to make a comparison between the growth of salt tolerant plants and less salt tolerant plants, under the same conditions as applied before. What do you discover?
How Can We Help Make a Difference?
Apart from adopting sustainable water practices in your own home and other places you use water, a great way for kids to get actively involved with protecting our water is by becoming involved in a Waterwatch group — or starting one if there isn’t one in the area they would like to work to protect.
Waterwatch was established by the Australian Government. It coordinates community participation in monitoring, protection and management of the water quality of our waterways. Waterwatch groups also come up with solutions to pollution problems and put them into action, as well as raising community awareness in the issues facing our waterways. It’s a great way to learn about the scientific principles involved in testing in a hands-on manner and learning to generate solutions and work in a group environment. A really worthwhile activity for the whole family.
You could also carry out your own monitoring of river areas or beaches, noting things such as litter, health of plant life and fauna, erosion and degradation, community use. Can you think of ways to help with any problems you discover?
What about a litter hunt, where you hunt for any litter in the area and dispose of it in a proper manner? Consider taking part in the annual Clean Up Australia Day, choosing a beach or river area to work in. Always wear strong gloves or use tools to pick up litter, in case of germs or sharp dangerous items such as syringes, glass and rusty metal.
Safety Note: Always be aware of safety issues when exploring or working near water. Young children should be supervised at all times, and even older children should be observed. It is also important to make sure all participants understand water safety issues, as well as what to do should an emergency occur.
Below are some useful websites for information on our water to use for research purposes and to follow up on areas of interest that you discover.
Hopefully these activities have given your children a more in depth understanding of water, how we use it and how we can protect it for the future. We need to instill the importance and urgency of addressing the problems facing our water today — and into the future. A clean accessible source of water is one of the most important aspects of creating a resilient life, as well as preserving vital ecosystems for all life on earth.




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BANIR AGROTÓXICOS.

Assine o Abaixo-Assinado virtual que pede o banimento dos agrotóxicos já proibidos em outros países do mundo e que circulam livremente no Brasil.

A Campanha tem o objetivo de alertar a população sobre os perigos dos agrotóxicos, pressionar governos e propor um modelo de agricultura saudável para todas e todos, baseado na agroecologia.

Assine já, pelo banimento dos banidos! Entre no link abaixo.

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