

One of the live oaks that bless my home

Saturday, July 6, 2013

The last chapter: Industrial agriculture

As I have argued in the previous three blogs, industrial agriculture is the largest human project that impacts the Earth more broadly than any other human activity.  One needs to keep in mind that compared with the global environmental impacts of industrial agriculture, a Macondo well-like blowout is a child's play.  I know it, because I co-wrote a book on this subject with the famous historian and archeologist, Joe Tainter.  For example, in the Amazon forest the underbrush fires set by humans affect 3 million square kilometers, an area of India.  See NASA for a summary of this global catastrophe.

Researchers for the first time mapped the extent and frequency of understory fires across a study area (green) spanning 1.2 million square miles (3 million square kilometers) in the southern Amazon forest. Fires were widespread across the forest frontier during the study period from 1999-2010. Recurrent fires, however, are concentrated in areas favored by the confluence of climate conditions suitable for burning and ignition sources from humans (who were burning the forest for soybean or sugarcane plantations). Image credit: NASA's Earth Observatory.
From an ecological point of view, industrial agriculture creates open, permanently immature ecosystems, most of which are reset by humans each year. To make things worse, the simplified single-plant species agricultural ecosystems are doomed to fall prey to the ever-evolving pests and weeds.   One can prove this gaping vulnerability using thermodynamics, regardless of what Monsanto claims. Because agriculture usually creates baby, mostly barren ecosystems, agriculture is subject to huge soil erosion rates. Soil then becomes yet another depletable fossil resource. In a previous blog, I told you that industrial agriculture cannot be sustainable, because it is continuously subsidized with depleting fossil resources, including fossil water. If you want to check what we are doing with water, go no further than Australia.

Speaking of fossil fuels, humanity extracts one cubic mile (4 cubic km) of fossil petroleum per year, and 150 cubic kilometers of water per year.  Most of this water is irreplaceable on human time scale, and can be regarded as another fossil resource.  Most of groundwater in the world is extracted for agriculture.

So just how big industrial agriculture is?  It is difficult to quantify agriculture's impacts on the Earth, but an analysis of the FAOSTAT data can illuminate some aspects of it.   So here is what I did:  I looked at the world's largest agrofuel and  livestock feed crops: maize (corn in the U.S.), soybeans, sugarcane, and oil palms (rapeseed in Europe).  I have accounted for all countries in the Americas, Asia, Africa, Europe, and Oceania. Separately, I looked at wheat and rice paddies.  The bottom line is shown in the three figures below.

To grow agrofuel crops, humans have taken out from the Earth's most productive tropical forests and savannas (prairies and steppes) an area equal to the Indian subcontinent.  The permanent damage to the health of the planet has been staggering, and humans will pay dearly for this insanity with their lives and health.  The two main food crops, wheat and rice, now span an area equivalent to that of the Democratic Republic of the Congo.  Please remember that these are just the field areas.  Now think about access roads, human settlements, working the land, moving this stuff around, moving the fertilizers in, storage and processing facilities, transport from the tropics to moderate latitudes, and so on.
The total area of the largely agrofuel crops, maize, sugarcane, soybeans, and oil palms (also rapeseed) has almost tripled over the last 50 years, and now it exceeds the area of India.  The total area of wheat and rice paddies has almost doubled to the size of the Democratic Republic of the Congo.  The agrofuel crops thrive in the U.S. and the tropics and have had an enormous negative impact on the environmental health of the planet.

An area of equivalent to the Indian subcontinent has now been taken out of the Earth's forests and savannas to grow mostly agrofuel crops.  Do you still think that slaughtering the most productive ecosystems on the planet is good for her (and our) health?

The area of wheat and rice paddies is now equal to the total area of one of the largest countries in Africa, the Democratic Republic of the Congo, which is neither democratic nor a republic.

With this fourth installment, I am ending - for the time being - my analysis of the multiple and complex influences of industrial agriculture on the state of the planet.  I hope that by now you understand that industrial agrofuels are a sure recipe for humanity to commit suicide faster and more completely.

Agriculture does not stop at land's edge.  Here is a large algal bloom on a beach in Qingdao, China (July 6, 2013). A central factor is the high supply of nutrients from agricultural runoff and wastewater, but nutrients injected by seaweed farming are also a contributor.  This green tide, spread over 7,500 square miles, is thought to be twice the size of an outbreak in 2008 that threatened sailing events during the Beijing Olympics,
In closing, please drive less, use less of everything, pester your "representatives" for electrical mass transit systems, and start buying locally.  Soon, you will have to use your friendly light rail or electric train, and buy local food.  And please do not pretend that I did not tell you for the nth time to start behaving like a responsible citizen of a living planet, and stop being a Pac-man-like consumer robot.

Here are the global areas of the crops included in my analysis.  The source of all the data is the FAOSTAT, and I wrote MATLAB programs that read the data in for all the countries on the planet and analyzed the crops I have considered.

By far the largest crop on planet Earth is maize, followed by rice paddies, soybeans, and wheat.  The sugarcane and oil palm plantation areas are much smaller but also grow fast.
In the last 50 years, the total area of maize agriculture has doubled to the area of Iran.
In the last 50 years, the area of rice paddies has increased by 30% to almost the area of Iran.
Over the last 50 years, the total area of soybean agriculture has increased 5-fold to the area of Venezuela. In the Americas, the soybean agriculture area has increased nearly 8-fold.  For an explanation, please look again at the NASA image of the permanently burning Amazon forest.

Over the last 50 years, the total area of wheat agriculture has not quite doubled to the area of Venezuela.  The jump in 1991, follows the fall of the Soviet Union, and jumps of wheat production in Ukraine and Russia.

Over the last 50 years, the total area of sugarcane agriculture has doubled to almost the area of Poland.
Over the last 50 years, the total area of the oil palm plantations has grown 6-fold, to almost the area of Poland.
P.S.P.S. April 6, 2015.  And U.S. prairie continues to be plowed for biofuel crops, emitting as much carbon dioxide as 23 coal-fired power plants operating for one year.

P.S.P.S.P.S.  April 8, 2015. There is no such thing as cheap agriculture.  Trillions of dollars per year of hidden costs of environmental devastation?

Wednesday, July 3, 2013

Satellites confirm: Industrial-scale agrofuels are not viable

The proper mass balance of carbon fluxes in terrestrial ecosystems, described in Appendix B of my OECD paper (2007), confirms the compelling thermodynamic argument that sustainability of any ecosystem requires all mass to be conserved on the average. The larger the spatial scale of an ecosystem and the longer the time-averaging scale are, the stricter adherence to this rule must be. Such are the laws of nature. Physics, chemistry and biology say clearly that there can be no sustained net mass removal from any large ecosystem for more than a few decades.

A young forest in a temperate climate, shown in the previous blog, grows fast in a clear-cut area and transfers nutrients from soil to the young trees. The young trees grow very fast (there is a positive net primary productivity or NPP), but the amount of mass accumulated in the forest is small. When a tree burns or dies some or most of its nutrients go back to the soil. When this tree is logged and hauled away, almost no nutrients are returned. After logging young trees a couple of times the forest soil becomes depleted, while the populations of insects and pathogens are well-established, and the forest productivity rapidly declines. When the forest is allowed to grow long enough, its net ecosystem productivity becomes zero on the average.
Paraphrasing Henry Paulson's famously surprised comments about the 2008 financial meltdown, who would think that there wasn't an infinite supply of these 2000-year  old redwoods? Yes, who would ever anticipate that?
Therefore, in order to export biomass (mostly water, but also carbon, oxygen, hydrogen and a plethora of nutrients) an ecosystem must import equivalent quantities of the chemical elements it lost, or decline irreversibly. Carbon comes from the atmospheric carbon dioxide and water flows in as rain, rivers and irrigation from mined aquifers and lakes. The other nutrients, however, must be rapidly produced from ancient plant matter transformed into methane, coal, petroleum, phosphates, as well as from earth minerals (muriate of potash, dolomites, etc.), - all irreversibly mined by humans.

Phosphates are just another form of fossil resource. Over millions of years, the annual cycles of life and death in ocean upwelling zones have propelled sedimentation of organic matter. Critters expire or are eaten, and their shredded carcasses accumulate in sediments as fecal pellets and as gelatinous flocculation termed marine snow. Decay of some of this deposited organic matter consumes virtually all of the dissolved oxygen near the seafloor, a natural process that permits formation of finely-layered, organic-rich muds. These muds are a biogeochemical "strange brew," where calcium -- derived directly from seawater or from the shells of calcareous plankton - and phosphorus - generally derived from bacterial decay of organic matter and dissolution of fish bones and scales - combine over geological time to form pencil-thin laminae and discrete sand to pebble-sized grains of phosphate minerals. Without phosphates there are no living plants or animals.  For more information, see Grimm, 1998.

Therefore, to the extent that humans are no longer integrated with the ecosystems in which they live, they are doomed to extinction by exhausting all accessible planetary stocks of minerals, soil and clean water. The question is not if, but how fast? For ancient agriculture the answer seems to be a few thousands of years, with a possible exception of China.  For modern agriculture, I would be surprised if it lasts for another century without a major systemic crash.

In the last two blogs, I gave you an abstract proof of no trash production in Earth's Kingdom, except for its dirty human slums. Are there any other, more direct proofs, perhaps based on measurements? It turns out that there are two approaches that complement each other and lead to the same conclusions. The first approach is based on a top-down view of the Earth from a satellite and a mapping of the reflected infrared spectra into biomass growth. I will summarize this proof here. The second approach, also described in my OECD paper, involves a direct counting of all crops, grass, and trees, and translating the weighed or otherwise measured biomass into net primary productivity of ecosystems. Both approaches yield very similar results.
Net Primary Productivities (NPP's = what's left for plants to grow and everyone else on the planet to eat) of Asia-Pacific, South America, and Europe - relative to North  America.  Now you understand why we plunder the tropics.  There, plants grow faster, and there is more money to be made with impunity by destroying the environment.  The phenomenal net ecosystem productivity of Asia Pacific is 4.2 larger than that of North America.  The South American ecosystems deliver 2.7 times more than their North American counterparts, and Europe just 0.85. These NPP's were calculated  from the NASA MOD17A2/A3 model.
Global ecosystem productivity can be estimated by combining remote sensing with a carbon cycle analysis. The US National Aeronautics and Space Administration (NASA) Earth Observing System (EOS) currently "produces a regular global estimate of gross primary productivity (GPP) and annual net primary productivity (NPP) of the entire terrestrial earth surface at 1-km spatial resolution, 150 million cells, each having GPP and NPP computed individually."  The MOD17A2/A3 User's Guide (2003) provides a description of the Gross and Net Primary Productivity estimation algorithms designed for the MODIS instrument aboard of the Aqua and Terra satellites.
MODIS, or the Moderate Resolution Imaging Spectroradiometer, is a key instrument that provides high radiometric sensitivity (12-bit) in 36 spectral bands ranging in wavelength from 0.4 to 14.4 microns, which is the range of infrared radiation emitted by tree canopies, grasses, and the Earth surface. Most of this radiation leaves the Earth and warms up the cold universe.  This is the main reason why life can persist on the Earth.

MODIS provides global maps of several land surface characteristics, including surface reflectance, albedo (the percent of total solar energy that is reflected back from the surface), land surface temperature, and vegetation indices. Vegetation indices tell scientists how densely or sparsely vegetated a region is and help them to determine how much of the sunlight that could be used for photosynthesis is being absorbed by the vegetation. MODIS is also very good at detecting deforestation and degeneration of ecosystems.

The bottom line is this:
Over the last 13 years, the measured Gross Primary Productivity of terrestrial plants on the planet Earth has been about 100 gigatons of carbon per year.  It changed by plus or minus a few gigatons of carbon from one year to another, because of the changing weather patterns each year. (Remember, the Earth is cyclic.) This is all the carbon sequestered by all of the photosynthesizing terrestrial plants on the Earth.  About  1/2 of this mass, 50 gigatons/year, has been maintenance food for these plants.  The remaining 50 gigatons of carbon per year have been used up by the same plants to grow and be eaten by all of the Earth's living creatures, some of which then ate other creatures.  Almost nothing is left after each orbit.  The Net Ecosystem Productivity (NEP, defined in the previous blog) has been about zero for the Earth. 
So, when someone says that 50 gigatons/year (1800 EJ/year) of biomass carbon are potentially available for our cars, tanks, and jets to burn as fuel, that person should be declared insane, and become a top adviser to the green nonprofits, think tanks, and world governments.  This person should also be a media star, simply because we live in an insane world in which money and mass are reported to be created from nothing.

In the next installment, I'll explain to you why modern industrial agriculture must be a long-term failure, and some of its global impacts.

Monday, July 1, 2013

Net Ecosystem Productivity is Zero on Planet Earth

In the last bog, I told you how the law of mass conservation governs the large-scale behavior of Earth's households - ecosystems - that must recycle all mass on average and export only low quality heat into the cold universe.  Now, I will give you a few useful definitions of cyclic processes, sustainability, and ecosystem productivity.

Let me start from stating the obvious:  We live in a spaceship we cannot leave, a gorgeous blue, white and green planet Earth that takes us for a spin around her star, the Sun, each year.

But this statement is imprecise. We really live on a vanishingly thin skin of the Earth, her ecosphere.   Think of this skin as of a thin delicate membrane, teaming with life and beauty, but incredibly fragile. We trample on this membrane and poison it.  Then we act surprised when it brakes and shrivels.

Practically all life on the Earth exists between two concentric spheres defined by the mean Earth surface at the radial distance from the Earth's center of R = 6371 km, and the top of the atmosphere at R + 100 km, or outer space at R + 400 km. Almost all of human existence occurs on the surface of the blue sphere (edge of the blue circle). As drawn here, the line thickness of this edge exaggerates the thickness of the life-giving membrane on which we live. This membrane is at most 20 km thick, from the deepest Marianas Trench in the Pacific Ocean (-11 km) to the top of Mount Everest (+9 km). Please hold an orange in your hand. When Earth is reduced to the size of this orange, her surface, on which we all live, is much smoother than the skin of your orange.

Life on the Earth is a cyclic process.  A cyclic process is anything that goes in circles and repeats itself with passage of time.  Days and nights are cyclic, so are years.  After each revolution around the Sun, our planet tries to return to the very state she was in a year earlier.  She reconciles all of her gross mass and heat balances almost perfectly.  (Remember, all mass stays on the Earth and heat is radiated into the universe.)  Therefore, on a human life scale, almost everything the Earth does is exactly cyclic.  The long-term changes in the Earth's climate, or geological epochs are much too slow for humans to observe directly. An abrupt climate change event that might last for a couple of thousands of years is a mere blink of an eye in the Earth's long history.  On the other hand, such a climate change is practically infinitely long from the point of view of humans and their institutions.

Some cyclic process can be sustainable, but only provided that they leave the larger environment unchanged after completing each cycle of taking what they need from the environment and returning their wastes to the environment.  Now you see that a sustainable cyclic process, such as a tropical forest, or a savannah, must recycle almost all of its material waste on an annual basis, so that the environment that feeds it remains healthy.
A sustainable process repeats itself without a loss of quality "forever,"  and leaves the environment intact "forever." 
Please define your favorite "forever."  Mine is about 4000 years.

By this scientific definition, modern industrial agriculture and agrofuel production that is a big part of this agriculture cannot be sustainable.  I repeat: The "renewable biofuels,"  as they are called by the cynical manipulators and the starry-eyed environmental fools, are anything but sustainable.

In a cyclic sustainable ecosystem plants transform sunlight, carbon dioxide, water, and other nutrients to feed themselves and all other living creatures in this ecosystem.  They all die in place and their chemical components are recycled almost exactly.  Only low quality heat leaves into the universe.  In a prairie ecosystem, a living bison eats a dead wolf, whose bones were incorporated into grass.  Nothing is wasted.

Several different ecosystem productivities, i.e., measures of biomass accumulation per unit area and unit time have been used in the ecological literature. Usually this biomass is expressed as grams of carbon (C) per square meter and per year, or as grams of water-free biomass (dmb) per square meter and year. The conversion factor between these two estimates is the carbon mass fraction in the fundamental building blocks of biomass, CHxOy, where x and y are real numbers, e.g., 1.6 and 0.6, that express the overall mass ratios of hydrogen and oxygen to carbon.

The following definitions are common in ecology:
  1. Gross Primary Productivity, GPP = mass of CO2 fixed by plants as glucose.
  2. Ecosystem respiration, Re = mass of CO2 released by metabolic activity of autotrophs, Ra, and heterotrophs (consumers and decomposers), Rh: Re = Ra + Rh, where decomposers are defined as worms, bacteria, fungi, etc. Plants respire about 1/2 of the carbon available from photosynthesis after photorespiration, with the remainder available for growth, propagation, and litter production. Heterotrophs respire most, 82 to 95%, of the biomass left after plant respiration.
  3. Net Primary Productivity, NPP = GPP − Ra
  4. Net Ecosystem Productivity, NEP = GP - Re - Non-R sinks and flows 
If you are interested in learning more, you can read some or all of my constructive OECD paper on biofuels and photovoltaics that got me blacklisted by the Organization for Economic Cooperation and Development headquartered in Paris.

And here is the killer of all industrial biofuels of whatever generation and industrial agriculture:
For all large, mature ecosystems, net ecosystem productivity (NEP) is almost zero.  In other words, one cannot continuously remove large quantities of  plant biomass from a large ecosystem, while simultaneously damaging the ecosystem services, and dumping waste.
For a short while, about a century or so, this mass removal can be accomplished by subsidizing the parent ecosystem with lots of fossil fuels and their products, but we already know that this "green revolution" is unsustainable.

There are countless examples of old thriving ecosystems that went extinct because of humans: Most of the Mediterranean coast and Lebanon were covered with ancient lush forest that was cut for fuel, charcoal, ship-building, and construction. Similarly most of Spain, parts of Portugal, Greece and Turkey, and otherwise most of Europe were completely deforested.  Most of Iraq, Syria and Egypt were devastated by the thousands of years of irrigation and agriculture, with the special emphasis on the last 150 years.  American prairie and about 1/2 of its thick rich soil were annihilated in 100 years. Much of the rich loess soil in northwest China has been flushed to the sea and gone with the wind. And so on.
The graph above shows how the net ecosystem productivity approaches zero in a particular forest. Forest ecosystem biomass fluxes are simulated for a typical stand in the H. J. Andrews Experimental Forest. The Net Primary Productivity (NPP), the heterotrophic respiration (Rh), and the Net Ecosystem Productivity (NEP) are all strongly dependent on stand age. This particular stand builds more plant mass than heterotrophs consume for 200 years. After that, for any particular year, an old-growth stand is in steady state and its average net ecosystem productivity is zero. This graph was adapted from Songa & Woodcock, "A regional forest ecosystem carbon budget model:  Impacts of forest age structure and land use history," J. Ecological Modelling, 164, pp. 33--47, 2003.

All major tropical rainforests in Brazil, Gabon, Congo, Indonesia, and all major savannahs, like the Cerrado in Brazil or Serengeti in Africa, have been here for millennia and are at NEP = 0.  Some of these forests have been here for most of the last 10 million years! These major planetary ecosystems can be destroyed only once in human history, and our beautiful Earth will become very, very hostile to us. (Not enough forest = no rain for starters.) 

The unimaginative, brutish humans are working overtime to annihilate these life-giving miracles of nature, and life on the Earth will never be the same at the time scales of human civilizations. That's thousands of years, and I could tell you dozens of gory stories about how uninhabitable for us the Earth will become. If you want to gain insight into what's in store for all of us, focus on the Middle East.

In the next installment, I will show you experimental verification of the incredibly important theoretical observation that NEP is close zero at the scale of the planet.