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.
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.
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.
Anyone who has battled kudzu will find this report rather hard to believe.
Three Squirrels
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.