Carbon Dioxide: Mankind's contribution to atmospheric CO2 so small it's not measurable - [MINISTRY]

Zenaan Harkness zen at
Mon Mar 25 00:49:05 PDT 2019

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TL;DR: most plant species studied appear to have optimal growth
characteristics with CO2 at well above current levels, in particular
at from 743ppm (measured) to 2700ppm (estimate of combination of CO2
and water usage optimization).

That is, plant life on this planet appears optimized for atmospheric
concentration levels of around 1200ppm.

  Atmospheric CO2 Concentrations At 400 PPM Are Still Dangerously Low
  For Life On Earth

    Over the Earth's history, atmospheric CO2 concentrations have
    ranged from 180 ppm to 7000 ppm, see Figure 1 below. On that
    scale we are in fact today barely above the Earth's record lows.
    Figure 1: Atmospheric CO2 concentration is just barely above the
    life-sustaining levels of 150 ppm.

    … It’s a fact that biologists have shown that once the
    atmospheric CO2 level falls below the 500 ppm level, plants
    really begin to suffer. Many of us have seen the video showing
    how plants grow faster under higher CO2 concentrations. The
    following charts show the growth curves of some plants as a
    function of CO2 concentration:

  Study: why CO2 levels are lower during global cold periods

    As recently as 18,000 years ago, at the height of the most recent
    major glaciation, CO2 dipped to its lowest level in recorded
    history at 180 ppm, low enough to stunt plant growth.

    This is only 30 ppm above a level that would result in the death
    of plants due to CO2 starvation.

  CO2 myth busted: Why we need more carbon dioxide to grow food and

    … as CO2 levels are raised by 1,000 ppm photosynthesis increases
    proportionately resulting in more sugars and carbohydrates
    available for plant growth.

  Plant Growth and Carbon Dioxide for Maximum Yield

    Plant growth requires a tremendous amount of Carbon Dioxide (also
    known as CO2). At the center of every plant cell is an atom of
    Carbon, which the plant has absorbed from the surrounding air.
    When all other growing conditions are kept ideal, Carbon Dioxide
    becomes the growth limiting factor. This means, as you increase
    the CO2 in your garden area, you will also increase the plant
    growth rates....and your yields.

    The ideal level of CO2 supplementation to maximize plant growth
    in a well maintained garden is generally 1500 ppm.

    In one final twist of irony, as you begin to increase plant
    growth and Carbon Dioxide levels you will reach a point where
    temperature becomes the limiting factor. In order to benefit from
    the highest levels of CO2 supplementation (1500-2000 ppm), you
    actually need to run your garden area warmer than normal (80-85
    degrees). On average, plants will also require an extra 30 watts
    of light/sq.ft. (70-80 watts/sq.ft.). Plants will use extra water
    and nutrients under these conditions, so make sure they are

    This has one implication which may offer you (the indoor
    gardener) a very nice solution to one of your most difficult
    problems. If all other factors are perfect in your garden EXCEPT
    your temperature runs a little high, you may be able to maximize
    plant growth AND solve your heat problem at the same time with
    the addition of CO2.

  The optimal CO2 concentrations for the growth of three perennial
  grass species

    Here, we examined the optimal atmospheric CO2 concentration
    effect on CO2 fertilization and further on the growth of three
    perennial grasses in growth chambers with the CO2 concentration
    at 400, 600, 800, 1000, and 1200 ppm, respectively.

    … the CO2 fertilization effect may sustain up to about 1000 ppm
    for leaf photosynthesis [46, 49] and 1800 ppm for grain yield of
    crops [50]. For example, Xu [23] examined the optimal atmospheric
    CO2 concentration of the CO2 fertilization effect on the growth
    of winter wheat and found that the optimal atmospheric CO2
    concentration was 894 and 968 ppm for total biomass and leaf

    … Elevated CO2 effects on plant biomass
    We found very strong CO2 fertilization effects on the aboveground
    and total biomass of the three species. The optimal CO2 levels
    for the aboveground biomass were 945, 915, and 1151 ppm, and for
    the total biomass were 915, 1178, and 1386 ppm for tall fescue,
    perennial ryegrass, and Kentucky bluegrass, respectively (Fig.
    1). However, an optimal CO2 of 895 ppm for the belowground was
    found only for the tall fescue, while no obviously optimal CO2 of
    the belowground biomass for the other two species was detected.
    Beyond the optimum, further elevating the ambient CO2
    concentration significantly reduced the growth of perennial
    grasses, indicating the adverse impacts of high CO2 concentration
    on the grass species.

    … we quantified the relationship between CO2 and WUE [water use
    efficiency] of perennial ryegrass through quadratic models and
    found that the optimal CO2 for WUE would occur at about 2700 ppm,
    which was much higher than those of the other two species (Fig.

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