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Has Plant Life Reached Its Limits?
hessian writes with this news from the New York Times: "Since 2000, Dr. [Steven] Running and his colleagues have monitored how much plant growth covers terra firma, using two NASA satellites in the agency's Earth Observing System. After they crunched the numbers, combining the current monitoring system's data with satellite observations dating back to 1982, they noticed that terrestrial plant growth, also known as net primary production, remained relatively constant. Over the course of three decades, the observed plant growth on dry land has been about 53.6 petagrams of carbon each year, Dr. Running writes in the article. This suggests that plants' overall productivity — including the corn that humans grow and the trees people log for paper products — is changing little now, no matter how mankind tries to boost it, he said."
I dont think there will be any actual planetary limits on crop production, just the matter of understading all of variables and how they interact.
What we're trying to do is grow SPECIFIC plants that are useful to people. We have never cared much if at all that what we are really doing is converting areas that grow one kind of plant to grow another kind of plant. If we were trying to increase primary production, no doubt we could do that, but we would be up against the same things that limit agriculture now: mainly water availability. But if you built a lot of greenhouses and water recycling systems we could probably increase primary production substantially.
... no matter how much plant matter humans harvest for various reasons, the Earth is able to replenish it to its maximum level.
The MidEast represents instructive activities of man over 10-20 thousand years.
Farming started between Turkey and Iraq of today, the fertile crescent, but land salting and rainfall reductions reduced that output. About 10,000 years ago the inland valleys of Egypt were incredibly productive, but later rainfall reductions then reduced that to desert.
Hence, natural rainfall changes altered growth a lot.
Man induced changes in that same region has caused vegetation to increase in one spot where there is economic incentive to figure out how to grow plants in marginal lands. Israel. They have developed techniques to make it work. Other peoples in the area haven't been as diligent.
Overall, maybe it is merely the cost-benefit ratio that determines whether mankind develops marginal lands.
Plant life has existed on land for 450 million years, which is plenty of time to reach an equilibrium where the total mass is no longer growing. It's actually a relief that human impact on the environment doesn't appreciably alter this equilibrium on the time frame of a few decades. Why is anyone surprised that there is a finite limit and that it is not subject to increase?
There are huge areas where very poor people are living on subsistence agriculture in small plots that are not very productive, especially in Africa and the backwaters of India and China.
Eventually these small plots will be joined into huge efficient and more productive farms with GPS-optimized fertilization and irrigation.
All it would really take is true land ownership rights by the current farmers (many countries do not allow their poor farmers to own the land, its ownership is governmental or transfers are highly restricted), as well as some investment in infrastructure. The first would allow farmers to sell their small plots into larger farms, and the second would make it worth the investment in the large farms to be able to bring the produce out effectively.
More development of service or manufacturing jobs would also be needed to absorb many of the current farm workers, as the larger efficient farms would be more automated and need fewer workers.
What can 30 years of observation tell about billions of years of plant life?
I, for one, think plant life will be there for a long time after humanity. Util it gets swallowed by the red giant sun.
Everyone here seems to be adding their own opinions none of which are suggested or demonstrated in the article. The basis for the conversation is that the green revolution should have made it possible for us to increase the green biomass. What we're seeing is that the green we grow is offset by wild green that grows less and the total green biomass remains constant. This isn't to say it will remain constant for any arbitrary length of time.
So this tells us we can grow one 2500 sequoia, or a similar mass of corn or wheat or soybeans in any given year. We also know that the tropical forests are under assault and because the wealth if tropical forests tend to be in their canopy and not their soul, a cleared area results in erosion and growing desertification. It will be interesting to see in 10 years when we can begin to see what the legacy of slash and burn forest clearing is doing to the Tropical places on earth. Add to that heat stress and drought and we will be seeing new and interesting changes.
Quantity of plant life does equal quality of plant life, much less diversity of plant life. Simply saying we have "X" isn't that terribly helpful without context.
So I'll provide some context and let's put a twist on this story which is being spun for political gain. In the year 1980 we had 4,453,831,714 people (the study starts in 1982 but close enough) In just 30 years the world's population grew 6,848,932,929.
In other words, we have grown the population of the world by 50% in thirty years and we still kept just as much plant life. Job well done with planting things to compensate for a growing population! We don't need to change a thing, we doing everything right. Neither answer is right of course, they are both ways of spinning a set of meaningless facts.
Point of the matter is that any given set of statistics can be twisted for a given political agenda with ease. The only thing this study does is show how easily meaningless data can be slanted for gain political purposes when the data is without merit. All it does is measure quantity without context. Might as well say a ranchers supports incredible wildlife, there's 200 cows and a dozen field mice.
Yes, because I'm fairly certain that the plant kingdom, given the choice of continuing to 'put up with' the human species, who has a chance of getting off this rock and possibly finding new planets / terraforming a new earth, or having them suddenly culled, giving them a slight increase in land (but ultimately destroying a lot of fertility) would happily choose the latter.
Because we've finally, I don't know, gotten around to commercial space rocket launches, and step two of colonizing a new planet is planting things we can eat / help us. Since humans run on oxygen, and plants are pretty nifty at producing a excess of breathable air (albeit from CO2, and a handful of right conditions), this would probably factor into our plans.
I am John Hurt.
Anyone who has battled kudzu will find this report rather hard to believe.
Three Squirrels
More plant growth is largely a simple input/output problem, because plant life is already highly-evolved and adapted to make effective use of the available resources. To get more plant growth you throw more of whatever the limiting resources are: phosphates, nitrates, water, CO2, land area (which builds in things like sunlight). Increasing the availability of these resources is costly, and, therefore, so is increasing plant growth. Unless you just want to fix a lot of CO2 (in which case the oceans, which were not part of this study, may be a better bet) you would actually prefer to limit your augmentation of natural plant growth. What you desire is high efficiency fields, where loss due to pests and drought is minimal, where most of the energy of the plant is invested in producing your desired food product rather than in fighting with weeds, etc., and therefore, where less resources need to be invested to produce the same output. The alternative would be to just grow so many plants that you get what you want out of it regardless of massive crop loss, but that is simply not the best solution. (And, of course, the effect on net plant growth is balances by the fact you are often displacing other plants for the purpose.)
When things get complex, multiply by the complex conjugate.
The more rocks we are on, the less important any one particular rock becomes.
Can you be Even More Awesome?!
Limits To Growth has never been proven wrong. This lie, originally created by Economists, has been told, and retold, and retold again, and I see it again in that Reason article, which I just read. Same lies! Try this: Go out and buy the original 1973 Limits to Growth book. Read it and look at the numbers. Now get CURRENT data on the same items. Compare. You will find that they match strikingly well.
The anti-Limits to Growth hatchet jobs tend to use the same lies. The standard approach, which is REPEATED in that lame Reason article, is to deliberately misinterpret LTG as predicting stuff it never said, then 'proving' that misinterpretation wrong. It's the standard 'Straw Man' argument, and that wretched Reason article does it AGAIN.
To repeat myself: go out and buy the original 1973 Limits to Growth book, or any of the more recent ones. Read it and look at the numbers. Now get HISTORICAL data on the same items. Compare. You will find that they match strikingly well. Nothing in Limits to Growth has been proven wrong, that is a FALSE MEME that represents a triumph of Disinformation.
... no matter how much plant matter humans harvest for various reasons, the Earth is able to replenish it to its maximum level.
Nope, the universe does not work that way, no matter how much we would like it to be so. You seem lack a basic understanding of ecological carrying capacity. When any species transgresses the carrying capacity of an ecosystem, it permanently reduces the carrying capacity of that ecosystem. This is basic Biology. The Reindeer of St. Matthew Island illustrate this point very well. In the future, please learn the basics of the topic before spouting off your (un) scientific opinion.
In 1972, the Limits researchers estimated known global oil reserves at 455 billion barrels.
Since this book isn't freely available online, and not within a reasonable time's distance away from me, how about you go open your copy, and tell us the actual figure that the book lists (since you claim it's not this 455 million barrels number).
Then go onto Wikipedia, and tell us the actual production to date.
But even this misses the point of the article: A higher price will cause supply to go up, and demand to go down. This is called the law of supply and demand, maybe you've heard of it.
Wonder what the public key field is for?
Sensational headlines sell newspaper, get TV viewers to stay up late to see the News, get research grants or inspire the general public to make direct contributions; besides there wern't too many lies told. What has happened is the truth was said in such a way that you heard something that wasn't said. For example saying that human activity has pushed an over-specialized sub-species that was dying out without regard to what we were doing to go extinct a decade sooner than it would have otherwise is as alarming as saying we are wiping out their habitat.
Apocalypse Cancelled, Sorry, No Ticket Refunds
Well, if you were ever to come up with evidence for your assertions, that would be interesting.
Nice argumentation, man! And it fits to ANY discussion about ANY topic! Did you elaborate it all yourself? Can I copy it? Please put it under CC license!
Strength, balance, courage and reason. If you know what's this about, contact me!
There's two problems in applying the law of supply and demand to oil:
1) The largest possible supply is limited. After all, there's just a limited amount of oil in the crust, and it will only be replaced at geological time scales (if ever - it's entirely possible that the specific conditions that originally resulted in oil formation won't be repeated again). There's another limit related to net energy oil extraction - that is, a point where extracting a barrel of oil requires more energy than said barrel will produce when burned. So yes, the supply (total extracted oil) will go up, but only asymptotically growing towards a limit, rather than towards infinity. That also means that there's a third limit: the point where the curve showing total extracted oil starts to flatten, meaning that the rate of extraction starts to slow, also known as peak oil.
2) The lowest possible demand is effectively limited, at least if we want to not die. We need to move stuff around, power agriculture, power industry, and power our homes. Homes and factories can be connected to the power grid, so we could in theory power them with nuclear power, but transportation can't. Current batteries have nowhere near the energy densities or safety where they could replace oil as a mobile energy source, and even if they did, we simply do not have the economic resources to replace old vehicles and do the necessary grid upgrades to power hundreds of millions of electric cars in the economic chaos caused by an oil price shock.
Basically, the law of supply and demand only works on luxury goods (you can live without) whose supply can be easily scaled by anyone who wishes to enter the field (no cartels controlling a significant chunk of the supply, barriers of entry or natural limits). None of these is true for oil, thus it won't obey the law of supply and demand except accidentally.
But of course a website using a slogan "Free minds and free markets" would have every incentive to pretend otherwise, since all solutions basically come down, at the very least, to government manipulating the price of oil to ensure a slow, steady increase to allow adaptation rather than a sudden "price wall" the economy would crash headfirst against.
Forget magic. Any technology distinguishable from divine power is insufficiently advanced.