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Earth Science

Has Plant Life Reached Its Limits? 209

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."
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Has Plant Life Reached Its Limits?

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  • Hmmm... (Score:5, Insightful)

    by NettiWelho ( 1147351 ) on Saturday September 22, 2012 @03:38PM (#41423459)
    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.
    • Re: (Score:3, Interesting)

      All limits are political. And the whole thing sounds like bullshit. Somebody's trying to work the commodities market.

      • Re:Hmmm... (Score:5, Funny)

        by fuzzyfuzzyfungus ( 1223518 ) on Saturday September 22, 2012 @04:22PM (#41423721) Journal

        All limits are political.

        And they say that postmodernism is dead...

      • Re: (Score:2, Interesting)

        by Taco Cowboy ( 5327 )

        All limits are political.

        Can't be more true than that.

        Hemp is band in many many countries just because some species of hemp happen to be marijuana.

        But the use of the hemp plant is much more than marijuana.

        http://en.wikipedia.org/wiki/Hemp [wikipedia.org]

        http://www.informationdistillery.com/hemp.htm [informatio...illery.com]

        http://www.treehugger.com/environmental-policy/perfect-plant-7-great-uses-for-industrial-hemp.html [treehugger.com]

        And most importantly, hemp grows very fast, and it can be grown in many soil types and also under various climate (from damp to arid) condition.

        If that rese

      • Re:Hmmm... (Score:5, Interesting)

        by budgenator ( 254554 ) on Saturday September 22, 2012 @07:38PM (#41424851) Journal

        Well, "primary production increase" => google.com = about 134,000,000 results (0.27 seconds)

        The results surprised Steven Running of the University of Montana and Ramakrishna Nemani of NASA, scientists involved in analyzing the NASA satellite data. They found that over a period of almost two decades, the Earth as a whole became more bountiful by a whopping 6.2%. About 25% of the Earth’s vegetated landmass — almost 110 million square kilometres — enjoyed significant increases and only 7% showed significant declines. When the satellite data zooms in, it finds that each square metre of land, on average, now produces almost 500 grams of greenery per year. Surprise: Earths’ Biosphere is Booming, Satellite Data Suggests CO2 the Cause [wattsupwiththat.com]

        or if you want original sources

        Recent climatic changes have enhanced plant growth in northern mid-latitudes and high latitudes. However, a comprehensive analysis of the impact of global climatic changes on vegetation productivity has not before been expressed in the context of variable limiting factors to plant growth. We present a global investigation of vegetation responses to climatic changes by analyzing 18 years (1982 to 1999) of both climatic data and satellite observations of vegetation activity. Our results indicate that global changes in climate have eased several critical climatic constraints to plant growth, such that net primary production increased 6% (3.4 petagrams of carbon over 18 years) globally. The largest increase was in tropical ecosystems. Amazon rain forests accounted for 42% of the global increase in net primary production, owing mainly to decreased cloud cover and the resulting increase in solar radiation. Climate-Driven Increases in Global Terrestrial Net Primary Production from 1982 to 1999 [sciencemag.org]

        Oh who wrote that paper? " Ramakrishna R. Nemani1,*,, Charles D. Keeling2, Hirofumi Hashimoto1,3, William M. Jolly1, Stephen C. Piper2 Compton J. Tucker4, Ranga B. Myneni5, Steven W. Running1
        Yes, I suspect your BS meter is running true. There seems to be a discontinuity between what Dr. Running said in 2003 about primary production and what he's saying in 2012.

    • Re:Hmmm... (Score:4, Funny)

      by ericloewe ( 2129490 ) on Saturday September 22, 2012 @04:10PM (#41423655)

      Hey, you have to tell us what bullshit generator you use, it actually sounds insightful to those who read the first part of the sentence.

    • 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.

      Is the planet infinitely big?

      • No, but it doesn't matter! As things get more scarcer they get more expensiver. So we just print more money, and buy it! Economy 3.0, baby!

        Or we substitute things. Run out of oil? Burn Hydrogen! Run out of bread? Eat cake!

        As long as our rate of breeding is at least twice our GDP, there's nothing humans can really do to affect our ecosystem. And even if we could, surely the ingenuity of our children will solve any problem we could possibly cause them.

        Or so I understand conventional wisdom to be.

  • by __aaltlg1547 ( 2541114 ) on Saturday September 22, 2012 @03:41PM (#41423473)
    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.
    • by fustakrakich ( 1673220 ) on Saturday September 22, 2012 @04:14PM (#41423669) Journal

      ...mainly water availability.

      The stuff falls out of the sky every day. We just have distribution issues, only a tiny percentage of which is technical. But be ready for real fast and massive climate change if we were to suddenly 'green the deserts'.

    • by icebike ( 68054 ) * on Saturday September 22, 2012 @04:27PM (#41423763)

      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.

      Well, that's a nice theory, but its simply not true.

      The amount of land dedicated to farming has not substantially increased, (in fact it has decreased) as farming becomes more efficient. Vast tracts of the
      midwest have returned to forest because there is simply no economic need to keep these lands under the plow.

      This whole theory is nothing but a huge rehash of the Limits To Growth, cited in TFA. Yet 40 years hence, LTG has been proven wrong in just about every single prediction they made [reason.com]. Their methodology and assumptions were simply wrong.

      Measurement of plant tonnage via satellite imagery has revealed that plants still grow just about everywhere they ever did. Wow. Major revelation.

      Yet the satellites seem to miss the fact that global food production has more than tripled since 1961, and worldwide, we are only using 7% more land in the process. In North America Europe, and Russia, we are actually cultivating less land, and producing vastly more food. Marginal lands have fallen fallow, and returned to prairie or forest of a 2 hundred years ago.

      Measuring the area covered by plants says nothing about the tonnage harvested every year off of that land. Nor does it say anything about the reduced pollution produced in the process, and the return of natural flora coverage. The total forest area [nationalatlas.gov] in the U.S. has been relatively stable for the last 100 years (currently about 747 million acres). The species may change (they always have over time). But its not because we have converted the land to farming. For the last 100 years, the biggest threat to forests has been housing development, not farming.

      • Trees are just another crop.
        • by icebike ( 68054 ) * on Saturday September 22, 2012 @05:02PM (#41424011)

          Trees are the default crop. Been this way since mankind was swinging from branch to branch,

          • by symbolset ( 646467 ) * on Saturday September 22, 2012 @05:32PM (#41424139) Journal
            Of course the question about terrestrial crops completely ignores the fact that the world is about 70% ocean. In terms of the ability of plants to convert solar energy to carbon trapping, the ocean has always had far more impact than the land does. In the ocean the entire height of the water column that solar energy can reach is teeming with algae doing photosynthesis - and below that other forms of life feed on the detritus. The evolution and distribution of various forms of algae and plankton are far more important.
            • another crop that we can harvest and create food and energy out of. I watched a ted talk a few nights ago that was just amazing the amount of energy these little buggers can hold.
              • by symbolset ( 646467 ) * on Saturday September 22, 2012 @07:47PM (#41424897) Journal

                Yeah, it's impressive. Almost nothing grows so fast as seaweed. Given the recent lesson of Japan tsunami debris we could probably just let an Algae farm go from Japan and harvest it on the West Coast of the US as it grew drifting across the open ocean. No need for fertilization, or weed management or any other service. Maybe other types of open sea aquaculture too like fish pens or mussel farms. In fact, by mixing the types the algae promote other sea life like plankton that the fish eat, and the fish feces feed the mussels and provide nitrogen for the algae, leveraging the lifecycle even more. And the mussels make mussel shells, which are primarily CaCO3 - so they reliably capture CO2 in a form that isn't readily released again. We can eat the seaweed, feed it to cattle, or process it for fuel - and it's useful for industrial chemical uses as well. The fish are protein. Probably get a good bit of bycatch as well like crabs, and no doubt shrimp and other types of sea life will swarm about the periphery of the farms. These farms could cover whole square miles each and work the ocean 150 feet deep. And we could work hundreds of thousands, or millions of them at a time - and feed the world's growing population for another hundred years.

                Add some solar powered geotracking satellite comm tech and shipping warning systems and we could put near-unlimited tracts of Pacific Ocean under agriculture. Wherever the farms wander, when it's time we can go harvest them. And then we can give those ships from China something to take back with them besides coal: the rigging framework the open sea farms are made of.

                We do need some new international agreements though to make it work because right now anybody who wanders out and catches such a thing on the open ocean is free to harvest it.

                I would like to see an experiment taken with just one buoy with a 100m cable drop supporting a ladder of buoyancy neutral arms 100 meters long every 20 meters or so of depth seeded with seaweed and mussels and dropped off of Japan in a current likely to take it to the US west coast. Let it go and see what you get. I'm thinking it would turn into a seaweedburg of epic proportions: a 100m radius, 100m deep cylinder of biomass rich in all forms of sea life, completely surrounded by a diverse variety of ocean creature feeding off it and its detritus.

          • Trees are the default crop. Been this way since mankind was swinging from branch to branch,

            So then it is trees and vines are the default crops.

      • by EnergyScholar ( 801915 ) on Saturday September 22, 2012 @06:32PM (#41424465)

        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.

        • Mod parent up!
          LTG is more applicable than ever with Peak Everything looming (or already here, for some values of "Everything".)

        • 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.

          • by ultranova ( 717540 ) on Sunday September 23, 2012 @08:35AM (#41427581)

            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.

            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.

        • by khallow ( 566160 )
          Well, if you were ever to come up with evidence for your assertions, that would be interesting.
      • by DevilM ( 191311 )

        Yea for yield increases! However, you failed to mention that ~80% of all arable land is currently in use. Grain productivity peaked years ago. And, depending on whether you like conservative or liberal estimates, we are going to need anywhere from a 40%-60% increase in productivity to mean the demands of the population in just a few decades.

        Did I mention the amount of arable land is also on the decline?

        • by icebike ( 68054 ) *

          Wrong.
          Less arable land is in use for farming today than any other time in the last 100 years. Do some research instead of spouting dogma.

      • The satellites aren't measuring food production. They're measuring primary production. My points about farming, which is the main thing humans to do modify the plant life on Earth, have to do with convenience. We farm where it's easy and cheap, so we don't usually bring new areas to biological production. We instead plow under whatever sorts of plants live where we want to farm and convert the land to producing crops that we like instead of the plants that naturally grow there. This results in little

    • 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

      We're also engaging in land "management" practices which result in these particular quantities of biomass. Rainforest beef, clear cutting, et cetera.

      we would be up against the same things that limit agriculture now: mainly water availability

      Not really. There's not too much of a shortage of contaminated water, and some plants will grow in pretty nasty water. Some species of bamboo stand out in this category, and they have the added benefit of being materially useful. Cutting down plants and making stuff out of them is one way to take carbon out of the atmosphere, and you don't have to do much to ba

    • Comment removed based on user account deletion
      • But I agree 100%, with water recyclers and desalination plants and greenhouses we could probably make deserts into breadbaskets but again here comes politics, you'll get the greenies screaming about threatening some lizard and the big agri lobbyists demanding protection and soon the whole thing would be another political clusterfuck.

        Presently there's no need for any such thing. We have plenty of agricultural capacity on land that's already under cultivation.

    • ... all that what we are really doing is converting areas that grow one kind of plant to grow another kind of plant.

      There has never been a point where we have converted growing areas that grow one kind of plant to grow another (unless they are already fields). When we rip down a rain forest, or clear-cut a woodland, or fill in a swamp, we are destroying an ecosystem of hundreds or thousands of species to grow one species. Biodiversity suffers, and our planet grows a little poorer each time.

  • by EmagGeek ( 574360 ) on Saturday September 22, 2012 @03:42PM (#41423483) Journal

    ... no matter how much plant matter humans harvest for various reasons, the Earth is able to replenish it to its maximum level.

    • by Guppy ( 12314 ) on Saturday September 22, 2012 @04:59PM (#41423985)

      ... no matter how much plant matter humans harvest for various reasons, the Earth is able to replenish it to its maximum level.

      Globally perhaps. But maybe not with the original species useful to humans, or in the same place.

      For instance, deforestation often leads to erosion and topsoil loss (see Haiti), such that even if human harvesting pressure were reduced, the forests could not grow back, instead being replaced by deserts, or grasses and scrub vegetation. The nutrients in the lost soil may end up being dispersed by wind and water, aiding plant growth elsewhere, such that global vegetative production does not suffer. But that doesn't help the local inhabitants much.

    • ... 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 [stuartmcmillen.com]. In the future, please learn the basics of the topic before spouting off your (un) scientific opinion.

  • by BoRegardless ( 721219 ) on Saturday September 22, 2012 @03:51PM (#41423525)

    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.

    • About 10,000 years ago the inland valleys of Egypt were incredibly productive

      The Nile basin and its tributaries remain some of the most fertile land in the world producing vast amounts of grain, dates, and other dry goods, and this hasn't changed for thousands of years. What does constantly change is the political climate of the region, regional conflict disupts the distribution of the Nile Delta output, affecting Kenya, Uganda, Sudan, Ethiopia, and really the whole of north Aftrica. Border wars perpetuate blight in the region, and have for thousands of years, mismanagement and glob

      • The pale-geologists have mapped inland valleys of Egypt, whose runoff formerly went to the Nile, which were incredibly productive and laced with rivers and lakes 7000 years ago which are now desert. Those are the formerly productive regions I was referring to.

        • Yes, also 12K yrs ago (this is from my faulty memory), the Nile ran west across the Sahara and nomadic humans inhabited the area in large numbers, a geological shift in the mountains where the Nile originates made it turn North along it's present course, creating a desert and dispersing the nomads but at the same time forming the fertile Nile valley. Another similar large scale river movement in Pakistan also dispersed the vast civilization that had arisen around it.

          Here in Australia many of the dairy fa
      • Don't forget the Aswan dam.
        What made the Nile valley fertile was the periodic deposition of mud by flooding.

    • by ppanon ( 16583 ) on Saturday September 22, 2012 @04:50PM (#41423927) Homepage Journal

      Israel. They have developed techniques to make it work.

      Yes, and those techniques involve irrigation using so much water taken from the Jordan River that the Sea of Galilee [marinebuzz.com] and the Dead Sea [smithsonianmag.com] have shrunk dramatically. At this point unless something drastic [jewishjournal.com] is done, in another 40 years Palestinians on the "West Bank" will be able to drive to Jordan.

      But yeah, those "techniques" are totally sustainable with no side effects, aren't they?

    • Why has the rainfall been reduced? Serious question.
      • "Why has the rainfall been reduced? Serious question."

        More like, why has the rainfall been diverted? The only thing that can really reduce total rainfall is global cooling. Unless it's the sort that would cause oceans to boil, global warming should produce more rain. Drought somewhere produces floods elsewhere.

        Changes in wind pattern are probably a major factor in this. Also deserts might produce a feedback loop where warm, dry land reduces the evaporation in a given land area or prevents rain from falling,

    • The Saudis sucked their aquifer dry irrigating wheat fields, had to give up large scale grain growing, and these days irrigate with desalinated sea water, powered by oil and gas.
      Within 15 years they will fall down the cliff way harder than Tunisia, Libya and Egypt.

  • by Anonymous Coward

    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?

  • by TheSync ( 5291 ) on Saturday September 22, 2012 @03:56PM (#41423567) Journal

    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.

    • Comment removed based on user account deletion
    • by icebike ( 68054 ) *

      I agree that Land ownership rights by individual farmers would, all by itself, improve production, and also improve preservation of the soil.
      If the land is theirs, people take care of it. Given just a modicum of education, even subsistence agricultural yields are expected
      to increase by 50 percent in the next 30 years [royalsocie...ishing.org].

      There would be no real need to sell it off to larger farms (this type of farming really only works well on flat land suitable for mechanization).
      With more production comes greater wealth. With

      • "I agree that Land ownership rights by individual farmers would, all by itself, improve production, and also improve preservation of the soil."

        No, it won't. Or at least it's not a silver bullet. Unless the individual farmer can grow everything by himself/herself, a farmer needs to sell his produce in order to buy the other food and items that he needs, meat, fertilizer, pest control, cellphone service etc. This would require access to fair markets not denominated by monopolies that can dictate the price at

  • by Lord Lode ( 1290856 ) on Saturday September 22, 2012 @03:56PM (#41423569)

    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.

  • by Genda ( 560240 ) <mariet@nOspaM.got.net> on Saturday September 22, 2012 @03:58PM (#41423575) Journal

    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.

    • by icebike ( 68054 ) * on Saturday September 22, 2012 @04:49PM (#41423921)

      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.

      No, there is no such "basis for the conversation", and there never was.

      Wherever did you get this idea that it was "possible for us to increase the green biomass", or the idea that we were even trying to do that?

      Earth reached its carrying capacity for plant life several hundred million years ago. Mankind is not going to increase or decrease that. Mankind doesn't even know how to begin to control the total biomass. The earth is on an energy budget dictated by the sun. Plants are going to grow at their own rate, and they are going to cover the earth wherever there is sun and water.

      That this guy, staring at photos taken in the mere past 30 years, sees no change is indication that things are working exactly as they always have. Totally out of the control of man.

      • Earth reached its carrying capacity for plant life several hundred million years ago. Mankind is not going to increase or decrease that. Mankind doesn't even know how to begin to control the total biomass. The earth is on an energy budget dictated by the sun.

        I was going to reply to the parent to your comment but then I saw this and decided I had to kill two birds.

        The Earth's energy budget is only one part of the equation. A lot of that energy budget is not being used to grow plants, and some of what isn't probably could be. The other major parts of the equation are human influence and CO2. Plants are mostly made out of carbon and virtually all of the carbon they're made from comes from the air. If you increase global CO2 then you can, in theory, make more plant

      • by Hatta ( 162192 )

        Wherever did you get this idea that it was "possible for us to increase the green biomass", or the idea that we were even trying to do that?

        If the limiting factor for plant growth is something other than incident sunlight, then it should be possible to increase the green biomass. One such factor could be fixed nitrogen [nih.gov]. Biological sources fix about 200Tg of nitrogen per year, the Haber process fixes about 100Tg. It's certainly not unreasonable to hypothesize that this could have a measureable effect on

    • The whole point of the Green Revolution was to make our crop plants more efficient at making food for us. Total biological output from the crops has not increased.
      • The whole point of the Green Revolution was to make our crop plants more efficient at making food for us. Total biological output from the crops has not increased.

        I'm puzzled by this comment. Isn't increased efficiency leading to higher biological output from plants?

        Plant one hectare of inbred corn, and one hectare of hybrid corn. Fertilize and control pests in exactly the same way and you're telling me the biological output of hybrid corn isn't greater?

        • Higher output in the context of what we eat, lower output in the context of 'wasted' stem material that we don't eat. Fertilizers/etc have led to increases in overall productivity, but the biggest gains have been made through altering the development to reallocate resources to the product we use.
          • by the biologist ( 1659443 ) on Saturday September 22, 2012 @08:11PM (#41425057)

            Modern wheat and rice are very short compared to the varieties in use before the Green Revolution. The height of the older strains allowed the plants to grow over the weeds. Modern farm chemicals did away with the weeds, which did improve yields. Without those weeds, the plants were now wasting much of their resources in growing tall. The Green Revolution, at least as I think of that term, came about when people realized the plants were wasting resources and that this waste could be reduced through directed breeding towards certain traits rather than just breeding for best yield in a generalized sense.

            The heterosis, hybrid vigor, taken advantage of in corn is definitely part of the current high yields. And yes, this probably is best described as part of the Green Revolution as applied to corn. That said, modern corns are also far shorter than historic varieties, with less energy going to produce the stems and more to produce seeds. Theres a lot of factors which go into it.

            Has this clarified my thinking?

        • We don't eat the entire biomass. Hybridised crops tend to be optimized for eating, so they produce more and larger edible bits - kernels, fruit, etc. That often comes at the cost of the rest of the plant - it's why, if you plant a high-producing fruit tree in your garden, you're supposed to pull off all the developing fruit in the first few years. These plants have been designed to produce lots of fruit, and they will, but if not managed, the energy diverted into fruit production will stunt the tree's growt

    • This article seems to be lacking important details, such as what percentage of this biomass is human cultivated. If say, 95% of the biomass in 1982 was wild plant growth, then even if we had quadrupled the 5% of human cultivated biomass with no losses elsewhere, then we'd only be at 115% of the 1982 biomass. And this isn't considering the losses of biomass due to land development and such.
  • by onyxruby ( 118189 ) <onyxruby@ c o m c a s t . net> on Saturday September 22, 2012 @03:59PM (#41423589)

    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 [infoplease.com] just 30 years the world's population grew 6,848,932,929.

    Over the course of three decades, the observed plant growth on dry land has been about 53.6 petagrams of carbon each year

    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.

  • Kudzu? (Score:5, Funny)

    by rueger ( 210566 ) * on Saturday September 22, 2012 @04:39PM (#41423853) Homepage
    Anyone who has battled kudzu will find this report rather hard to believe.
  • Did anybody notice that this leveling off of plant biomass is *despite* the enormous amounts of energy spent on irrigation, fertilizers and pesticides, aka the Green Revolution, and industrial food production?
    Oh and most of that energy is produced from fossil fuels. *That* is why we're way beyond the Earth's carrying capacity, why world food production is slacking, prices are rising and we see food riots.
    And I didn't even mention global warming (yet, heh.)

    Watch https://www.youtube.com/watch?v=aRLg8No0RVQ [youtube.com].

    • Actually it's not about agricultural production but total plant production, and the implication is that the planet's plants can't keep up with human CO2 production. An other study have reported a slightly less than 7% increase in Net production and almost half the increase occured in tropical rain-forrests, curiously the paper was co-author by Dr Running as well.

  • by physicsphairy ( 720718 ) on Saturday September 22, 2012 @04:49PM (#41423925)

    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.)

  • Nature seeks an equilibrium, we're the ones that insist on spreading like viruses. The point is there are factors that when we plant more crops it tends to remove the resources needed for native plants. Look up Global Dimming and you'll find nature is also compensating for increased CO2 with more cloud cover moderating the amount of light reaching the Earth limiting the warming. Unfortunately it also reduces the light plants have available reducing the overall amount of green plants. This trend has been rec
  • The observation was that total plant life is not increasing. How does that imply a limit? What factors indicate that plant life should be increasing?

    During the recent global recession, many people's incomes have remained stagnant, or decreased. Does that mean those people have reached the limit of their income potential?

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