The requested URL /scielo.php?script=sci_arttext&pid=S0074-02762011000700016 was not found on this server. has increased significantly in the last decade or two. Our governments should be spending serious money on researching evaporation limiting methods, but do not appear to be doing so, just as they are doing next to nothing to limit the cause of the problem – What can be done economically to reduce the evaporation losses of the increasingly precious and scarce water in storages across southern Australia? Whatever is done will cost money, but often to get by without water is not an option, we simply must have the water! In my own dams I loose far more water to evaporation than I use for Annual evaporation in the Clare Valley, from a Bureau of Meteorology map on the Net, is between 1600 and 1800mm per year, and the Northern and Yorke Natural Resources Management Board has estimated that evaporative losses from farm dams (2100ML/yr) is greater than the amount of irrigation

water that is taken from them. In warmer areas – and most of South Australia is warmer than Clare – the losses would be even worse. The simple loss of water is not even the whole problem; evaporates any salt – there is always salt in natural water –so the salinity of the remaining water increases. The higher the salinity of water, the more problematic is its use. On a calm day the air close to the surface of the water in a storage becomes saturated with water vapour. So long as the layer of saturated air stays put, there will be little further evaporation, but if there is a wind the saturated air layer will be continually mixing with dry air and evaporation will continue. Evaporation can be reduced by either providing some sort of a barrier between the water and the air or by somehow slowing the movement of the air near Planting a wind-break of trees and shrubs around the dam will help to some Full dams, a sight we don't see so often in recent years.

(My dam, the nearer one, filled about two years out of every three in its first ten years, in the next six years it did not fill at all. In the six years since installing AgFloats it has never been dry.) Note that the wall of my dam is vegetated. Installation of some evaporation barriers would involve heavy damage to this.renaud air purifier shanghai The capacity of my dam is about 2.5ML.honeywell f100f2010 media air cleaner 20 x 25 Consideration should also be given to what will happen to dust and leavesozein air purifier review that will blow onto the devices; what happens to the rain that falls onto Some systems require pumping to remove rain water from the cover;

increasing costs and labour. Several of the products use expanded polystyrene which, in my experienc, becomes chalky and powdery on the surface after long exposure to sunlight. Obviously if your dam leaks then an evaporation barrier is not going to All of the products that seem likely to be acceptable and effective are going to stop you from swimming in your dam. My reading on the evaporation barrier subject indicates that if the water contains a significant amount of organic matter (leaves, algae,there must be significant contact between air and water to avoid the water going bad. If contact with the air and light is cut off the algae and inverbebrates They and the leaf litter will then rot and this will quickly use up all the oxigen in the water; methane and hydrogen sulphide (rotten egg gas) are produced by bacteria that live in anoxic conditions, and quite probably the water will become acidic. This problem can be avoided if most of the organic matter is removed from

the water before it goes into the sealed storage. Evaporation reduction does not come cheap; either you pay for ready-made fixes in money or you pay for home-made fixes with less money but a lot The costs of the individual products can be found in A rough calculation: my case – Average annual evaporation in my area (Clare, SA) is about 2m. this represents something like a megalitre of water (it depends very much on how much water is in the dam at the start of the evaporation If the cure I use reduces the evaporation by 80%, costs $7000 and lasts twelve years this is 800kL × 12 = 9.6ML; $7000 for 9.6ML is $0.73/kL. This might be compared with using a big covered tank. I priced a 250kL tank at $15 000. Assuming a life of 15 years we have 250kL × 15 = 3.75ML; $15 000 for 3.75ML Also the evaporation barrier will make up to 2ML available to me while the tank would only have given me an eighth as much.

I will leave it to the accountants to calculate money costs, depreciation,Choosing flooring for your home can be a confusing experience.The options can be daunting. The best place to start is to speak with a professional so you get the information that you really need. We had a chat with Mr Amini at Collingwood Flooring Xtra and he gave us the lowdown of the different types of flooring available, the benefits and drawbacks of each type and helped us out with a handy list of questions to ask the professionals when you’re flooring or re-flooring your home. A synthetic material that’s sold by the square metre from a large roll. It can be cut to fit the exact measurements of the room you’re flooring. How much does it cost per square metre? Around $30 for supply and $55 laid. You’re looking for a cheap and cheerful flooring option in a kitchen or bathroom. Be careful what you lay lino on top of because traditionally it’s secured to the floor with heavy duty glue, which may damage the under surface.

It’s worth considering why you are relaying the floor. If it’s a renovation to attract new buyers it’s worth noting that many buyers have a positive view of wooden flooring, and a lesser view of lino, so it may not help you achieve your maximum sale price. A synthetic and inexpensive flooring material that is traditionally designed to imitate wood. It’s sold in tile or plank form. Similar to lino, it’s around $25 for supply and $55 laid although keep in mind that laminate is easier to DIY than other types of flooring so you might be able to save on labour costs. You’re looking for a cost effective and easily removable flooring solution. It has a much better reputation than lino and won’t damage the existing floors in your home. Better steer clear of laminate floors if you live in an apartment though as it’s not very sound proof. A more cost effective alternative to solid timber, bamboo is layered flooring material that is cross-grained to counter act its natural tendencies to expand and contract with temperature changes.

Ideal as an alternative to solid wood in areas that are moist and humid. About $45 for supply only and $80 to have it laid. You’re looking for a cost effective and environmentally friendly alternative to wood. It’s also great for bathrooms and damp climates where solid timber wouldn’t cope. Exactly what it sounds like – solid timber planks. This also includes parquetry flooring which is a mosaic style design of smaller pieces of solid timber. It really varies when it comes to solid timber but costs start at $170 per square metre depending on hardness and go up to $300 laid. Our experts say you’d be hard pressed to find a professional flooring store that will sell supply only as it’s very tricky to DIY timber flooring and can be really expensive if you don’t do it properly. If it’s in your price range and you can afford the regular maintenance. Solid timber flooring retains heat beautifully in cold climates and will give your home a warm and natural ambience.

Not recommended for moist areas or humid climates though. Make sure you budget correctly because there can be hidden costs in flooring such as installation and maintenance. Always ask if your flooring of choice is appropriate for where you want to lay it. Climate, sound control and heavy foot traffic can all have a significant impact on the correct choice of flooring. It’s important to ask about upkeep of your flooring. For example lino is a very cost effective option but may not be easy to repair if it becomes damaged. Solid timber is extremely durable but only if it’s properly sealed after installation. Be sure to ask about the future of your flooring to save yourself money both now and down the track. Although the price of flooring can vary from $30 per square metre for lino to $300 for solid timber the durability varies accordingly. Cheaper flooring options will save you money in the short term but when their more durable counterparts outlast them by 20 or 30 odd years then it’s important to consider replacement in your budgeting.