Are we covering the world over with concrete?

I was checking out some environmental websites today, and I noticed that one of the themes I kept running across was basically this: That we're covering over all the land on Earth with concrete, and that we're running out of natural places (even man-made ones like farms and parks) and wilderness. How can we know if that's true if we don't get to see any numbers?

So, then I started to try to look up land use statistics. That proved to be very difficult. Basically I came up with several different statistics that all contradicted each other. For example, I read that the amount of land in the U.S. covered in concrete (this includes every building, road, etc.) was as little as 3% of the nation's land, or as much as 40% of the nation's land, depending on which website you were reading.

I couldn't find any statistics for the whole world. I tried such key words as "land use", "urbanization", and "urban sprawl".

Can anyone help me out here? I really want to find this information, and find the truth!

Original and Current Forest Cover across the Globe

What you are looking for is Total Impervious Area calculations however it is difficult to gauge.

www.heinzctr.org...

Total impervious area is difficult to measure. Measurements must be made on a fine scale to account for small areas such as sidewalks and driveways, but the finest-scale satellite information generally available cannot distinguish features of this size. Many local planning and environmental management programs collect this information, but the data have not been compiled regionally or nationally, nor are there standard methods for estimating the amount of impervious surface.

Well, that's pretty cool but not quite what I was looking for. And I'm not looking for precision down to the area sidewalks take up though it would be neat.

Here's one website I found in my reasearch:

biology.usgs.gov...

According to this website (which is run by the USGS and uses their data), the approximate percentage of the total land area of the U.S. that is urbanized (which is, for all practical purposes, also covered in concrete) is about 3%. Not too bad, IMO!

Urbanized land includes all city areas, roads, parking lots, factories, military areas, and even landfills... (Landfills, by the way, appear to take up 0.1% of the total land area of the U.S.)

Also, 40% of the total land area of the U.S. is used as pasture land for livestock; and 15% of the total land area of the U.S. is used for crop lands for food (interestingly, 12% is for food for the livestock, and only 3% is the food for us humans).

Interesting statistics! Does anyone else have any other sources I can look up in my research? Or perhaps comments on that which I just found?

Thanks again!

Here's another question I'm searching for answers to -- is it possible for nature to reclaim land that has been covered over with concrete, but abandoned, with proper human intervention? For example, in the U.S., outside of several major cities (Kansas City, Missouri and Cleveland, Ohio are a couple of random examples) there are big industrial parks which are no longer in use. They sit, abandoned, rotting away.

Assuming we leave all the stuff buried underground (such as pipes, wires, etc.) for simplicity, if we simply bulldozed all the bulidings, dug up the concrete, and re-laid dirt & soil there, would it once again over several decades become a forest or grassy plain? Or, once the damage is done, is it done forever?

P.S. -- Would it be possible if this were moved to the new "Fragile Earth" forum?

Originally posted by ThunderCloud
and 15% of the total land area of the U.S. is used for crop lands for food (interestingly, 12% is for food for the livestock, and only 3% is the food for us humans).

That because those beefs in hamburgers are very inefficient way of producing food.



One thing which hasn't been mentioned: Cities tend to grow to areas where soil is fertile.
And that's the problem especially in many population rich countries with small area.

I dont think we are covering the earth in concrete in a way that will cause problems. If you have ever flown in a plane you know that there is still A LOT of untouched raw land out there. I dont think that the earth will look like the death star or anything, at least not for a few thousand more years

As far as cleaning old industrial sites up and trying to restore them to their natrual state I'm sure it could be done just as most things if enough time, money and energy was spent. Who will pay for it there? there is no financial incentive at all for private companies to do this, and the govt already has enough on their plate.

People like green, which means there will always be grass and trees.

The 3% sounds more like the US, While that 40% was probably referring to cities only.

and yes land can be restored, the US government restores land after there done using it for whatever natural resource it once had is gone. There also alot of people like "green peace" who tries there hardest at protecting the forest and other green things.

The UK is alright with this, as you may know the UK has alot of countryside and is alright, especially the North of England where many farms are

The problem with the big cities is that they make the land impermeable.

One Portuguese politician who is an specialist is this area was always trying to convince people to not build on the slopes of the hills, because when it rains the land will absorb the rain, but the concrete and the asphalt do not, and the result is that the rain from all that area is not absorbed and concentrates on the low lands besides the hills, creating floods in places where naturally there was not a reason to have floods.

The US is a big country. I can't even speculate how much is still natural. And of course a lot of what we call natural--parks and such--isn't really natural; it's mowed and landscaped.

I know in the city where I live it sure seems like things are getting paved over. There's also a lot of overhead wires-- power lines, telephone lines, cable lines... as well as an absurd amount of signs. It's just amazing to me how much resourse--mining, refining, manufacturing--go into making signs that say something trivial. We continue to strip resources from the earth as if there is an unlimited supply. People who grew up in this environment treat it as normal. Having come here from the country, it sometimes seems to me as if humans are a plague upon the land...

cimmerius - If you think humans are a plague then exterminate yourself.

and whats the difference in something is mowed or not? Its still normal unpaved land.

and the US isn't paving everything over, if you believe they are then I would ask you to look up info on Bostons Big Dig. It a multi-billion dollar effort to make the city not only be easier to travel in but as well as make it greener, they put some roads underground in tunnels and put grass and fountains and parks above where the roads used to be, which will also make the city less smoggy.

Whoa, slow down Murcielago. Most humans can be a plague without all humans being held accountable. The difference in something being mowed or not is that it is touched by human hands that way. Most of the native plants will disappear when that happens, which leaves it hardly natural.

I really wonder how Boston's Big dig is going to make the city less smoggy. When cars are underground, they still produce exhaust. Unless they have some plan to filter it or something, you're running into a blind alley.

Originally posted by shbaz
Whoa, slow down Murcielago. Most humans can be a plague without all humans being held accountable. The difference in something being mowed or not is that it is touched by human hands that way. Most of the native plants will disappear when that happens, which leaves it hardly natural.

I really wonder how Boston's Big dig is going to make the city less smoggy. When cars are underground, they still produce exhaust. Unless they have some plan to filter it or something, you're running into a blind alley.

I didn't say everyone I had his name in bold for a reason.

Who cares if some native plants die.

and smoggy wasn't the right word, ummm. how about smelly (exhaust fumes). and yes, the tunnel has ventalation shafts that go to a building with big fans and they get released elsewhere (I.E. - not in the heart of Boston).

Here we go again..........

Why does something 'touched by man' become un-natural? Isn't it still a plant? Isn't man 'natural'? I am soooooo tired of hearing this. If you said 'unchanged', or 'wild' then I would agree with you.

As often as I help people who are stuck in the mud (or get stuck myself!!!) I can guarantee you the earth isn't covered in concrete!

No, man isn't natural.

Nature: The natural physical world including plants and animals and landscapes etc.

That is, not altered from the state that erosion, weather, and what little change animals could make to it.

If you regard man as an animal, I suppose that would invalidate my point, but animals don't drive cars, construct buildings, mix concrete, and etc. In essence, "unchanged" and "wild" are covered in the definition of natural.

Who cares if native plants die? If you have to ask, then you probably don't understand most of this thread at all.

Thunder, in response to your initial question -

3% is likely a good estimate of the land in the Us that is covered in some impervious material, be it concrete, macadam, or buildings. Pretty decent, by most accounts. Also consider the areas where the soils has been compacted to the point where it is actually imperivous. This may account for another 1% or so of the land cover in the US. 4%, not too bad. Another source of information for you is available form the Natural Resources Conservation Service, which conducts a National Resources Inventory anually.

Now, why are you asking this question? Land use has a dramatic infulence on many environmental fators, from air temperature to runoff. The most readily impact to see (especially as I sit surrounded by the remnants of hurricane Ivan) is it's effect on stormwater runoff. But, impervious areas are only part of the equation. Cultivated fields that expose the bare earth have a higher
runoff factor than those coverd in a grass, which in turn have a higher runoff factor than forested areas.

Higher runof leads to flash flooding, and less groundwater recharge. Ways to combat these negative effects? Promote more land cover that encourages stormwater infiltration into the soil, or slows the runoff down.

Your other question, can abused land be reclaimed? The answer is yes. But, as others have said, it takes money, time and effort. The federal government does spend some money towrds this effort, but sadly not enough to recover what we have abused. IMHO, the government should impose harsher penalties on individuals and/or corporations that leave an adverse impact on the land, and use these resources to recover them.

Originally posted by shbaz
Who cares if native plants die? If you have to ask, then you probably don't understand most of this thread at all.

Here is my question:

What happens when we invent flying vehicles and the concrete roads become obsolete?

Oh wait! Still ideal for walking on...especially if you use a roller backpack!

Originally posted by shbaz
No, man isn't natural.

Nature: The natural physical world including plants and animals and landscapes etc.

That is, not altered from the state that erosion, weather, and what little change animals could make to it.

If you regard man as an animal, I suppose that would invalidate my point, but animals don't drive cars, construct buildings, mix concrete, and etc. In essence, "unchanged" and "wild" are covered in the definition of natural.

Who cares if native plants die? If you have to ask, then you probably don't understand most of this thread at all.

Its obvious that humans are animals. Why should humans be classified as anything else?

As for the point that animals don't drive cars that is true, but animals do make some sort of buildings, just think of the castors. Not only they make constructions as their constructions change the surrounding area.

Originally posted by shbaz

Who cares if native plants die? If you have to ask, then you probably don't understand most of this thread at all.

Who said I didn't care if native plants die? I sure didn't. Almost all plants are 'native' the only ones that aren't are those that have been created in a labratory. And i'm afraid I just can't get worked up about replacing crab grass with some good kentucky blue!

Humans are animals. They are obviously part of the animal kingdom, and to attempt to place them somewhere else is just plain wrong. Get real.

And finally, the part I qouted. What did I say that made me some kind of an idiot? Ah I see now, I said something that you did not agree with so obviously I am an idiot!