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Biospheric Breakdown: What We Must Do to Prevent It?
Volume 8, Number 32: 10 August 2005

Periodically, many of the scientific community seem compelled to engage in a major hand-wringing exercise, wherein they lament the many environmental problems caused by the various operations that provide the vast amount of food and water that are needed to sustain the planet's ever-expanding human population, and where they subsequently put forth various suggestions for dealing with the situation, the most recent case in point being the paper of Foley et al. (2005) in the 22 July issue of Science.

The problem is this: to feed the number of people that will reside on the earth near the mid-point of the current century will require something on the order of a doubling of global food production (Tilman et al., 2001), which will require similar increases in the usurpation of land (Tilman et al., 2002) and water (Wallace, 2000) to meet this objective.

In providing a sobering perspective on the magnitude of the problem, Foley et al. report that "human activities now appropriate nearly one-third to one-half of global ecosystem production," which means that in a mere fifty years humanity could well be appropriating nearly two-thirds to all global ecosystem production simply to support their existence, which would leave essentially nothing for what some have called "wild nature" (Green et al., 2005).

What can be done to avert this looming ecological disaster, which would essentially spell extinction for the vast majority of all higher life forms on the planet?  Foley et al. suggest a number of obviously important things, including "increasing agricultural production per unit land area, per unit fertilizer input, and per unit water consumed; maintaining and increasing soil organic matter ... and maintaining local biodiversity."  But how are these things to be accomplished?

Foley et al. provide several examples where site-specific measures have been taken to address various items on their list of needs.  Nothing, however, compares with what can be done by merely allowing anthropogenic CO2 emissions to take their natural course as technological innovation takes its natural course.  Since the inception of the Industrial Revolution, for example, we calculate in our Editorial of 11 July 2001 - based on the work of Mayeux et al. (1997) and Idso and Idso (2000) - that the 100-ppm increase in atmospheric CO2 concentration that has been caused by the historical burning of fossil fuels has likely increased agricultural production per unit land area by 70% for C3 cereals, 28% for C4 cereals, 33% for fruits and melons, 62% for legumes, 67% for root and tuber crops, and 51% for vegetables.  In addition, it has significantly increased agricultural production per unit of water used (see Water Use Efficiency (Agricultural Species) in our Subject Index) at the same time that it has similarly increased nutrient use efficiency (see Nitrogen Use Efficiency and Phosphorus in our Subject Index).  Furthermore, as a result of these several growth-enhancing phenomena, atmospheric CO2 enrichment simultaneously increases soil organic matter content (see Soils (Carbon Sequestration) in our Subject Index); and there is evidence to suggest that elevated CO2 concentrations tend to maintain, or sometimes even enhance, local and regional biodiversity (see the various sub-headings under Biodiversity in our Subject Index, as well as our major report The Specter of Species Extinction: Will Global Warming Decimate Earth's Biosphere?).

The above-listed consequences of the ongoing rise in the air's CO2 concentration are precisely what Foley et al. acknowledge are needed to avert the incredible catastrophe that otherwise appears unavoidable a mere five decades from now.  We also note that these beneficent effects of atmospheric CO2 enrichment are bestowed without regard for national or regional boundaries and among the rich and poor alike.  As the sun that shines upon all, so too do rapidly-mixed anthropogenic CO2 emissions increase the robustness of vegetation everywhere on earth; and without the help of this phenomenon, we will not succeed in maintaining any semblance of the natural world much beyond the midpoint of the current century.  Yet some people claim these same CO2 emissions pose a greater threat to humanity and the well-being of the biosphere than nuclear warfare and global terrorism.  How horribly wrong they are!

Sherwood, Keith and Craig Idso

References
Foley, J.A., DeFries, R., Asner, G.P., Barford, C., Bonan, G., Carpenter, S.R., Chapin, F.S., Coe, M.T., Daily, G.C., Gibbs, H.K., Helkowski, J.H., Holloway, T., Howard, E.A., Kucharik, C.J., Monfreda, C., Patz, J.A., Prentice, I.C., Ramankutty, N. and Snyder, P.K.  2005.  Global consequences of land use.  Science 309: 570-574.

Green, R.E., Cornell, S.J., Scharlemann, J.P.W. and Balmford, A.  2005.  Farming and the fate of wild nature.  Science 307: 550-555.

Idso, C.D. and Idso, K.E.  2000.  Forecasting world food supplies: The impact of the rising atmospheric CO2 concentration.  Technology 7S: 33-55.

Mayeux, H.S., Johnson, H.B., Polley, H.W. and Malone, S.R.  1997.  Yield of wheat across a subambient carbon dioxide gradient.  Global Change Biology 3: 269-278.

Tilman, D., Cassman, K.G., Matson, P.A., Naylor, R. and Polasky, S.  2002.  Agricultural sustainability and intensive production practices.  Nature 418: 671-677.

Tilman, D., Fargione, J., Wolff, B., D?Antonio, C., Dobson, A., Howarth, R., Schindler, D., Schlesinger, W.H., Simberloff, D. and Swackhamer, D.  2001.  Forecasting agriculturally driven global environmental change.  Science 292: 281-284.

Wallace, J.S.  2000.  Increasing agricultural water use efficiency to meet future food production.  Agriculture, Ecosystems & Environment 82: 105-119.