We’ll discuss here three kinds of energy ‘crises.’ One is in supply of highly concentrated forms. One is with respect to places in the world using less concentrated forms (like firewood, for example). The third has to do with the use of fossil fuels to support unsustainable industrial modes of agriculture.

There are measures of energy content (calorie, for instance), but really none for concentration, which is what we’re particularly interested in in terms of the evolution of human societies, and the differences between, for instance, industrial and agrarian societies.

The 2nd law of thermodynamics, dealing with entropy, basically describes movement of energy from concentrated to dispersed forms. In the process, something is lost–no matter how organized and structured human bodies might be, or an elephant, or a city or a skyscraper, or a sophisticated diagnostic machine used by Jiffy Lube to tell you how much your ‘oil change’ is going to cost you, there is slightly more disorganization or disruption, but it is dispersed. This is the idea of entropy, the state toward which the universe is steadily, if glacially, moving.

Ecosystems and terminology

• Ecosystems—dynamic complexes of interacting biotic and abiotic elements
• Abiotic (soil, minerals, water, land forms, climate) and biotic elements
• Terrestrial ecosystems—this would include forests (tropical, temperate, deciduous, coniferous); grasslands, savanna (how open is canopy?); desert; tundra; mountains
• Aquatic ecosystems—lakes, ponds, rivers, estuaries, oceans, inland seas
• Limiting factors—temperature and rainfall (latitude and altitude also pose limits, in terms of temperature, day length, etc., sometimes affected by climate variation, though–for instance, the moderating effect of the Gulf Stream on Europe’s climate)
• Populations (aggregations of species)
• Communities (aggregations of populations within ecosystem)
• Evolution, co-evolution – differential reproduction, interaction
• Diversity (think in human societal terms as well, even languages, economic or political systems, cultures) If rapid change occurs in an environment, how does genetic diversity within a species population increase its chances for survival?
• Habitat, succession, climax species
• Food pyramid/web—represents, trophic or feeding structure of biotic community
  • Hierarchical—producers, consumers, detritivores
• Uses of energy
  • Production (accumulation of biomass)
  • Respiration (self-maintenance)
  • Storage (dead organic matter)
• Entropy—process of energy degradation from high (concentrated) to low (dispersed) grade—energy degrades as it passes through ecosystems
• There is therefore a need for continuous, high-quality input of energy, or storage capacity (when input is low)—where is energy stored in a natural or human ecosystem?

Most productive ecosystems

1. estuaries, springs, coral reefs, alluvial plains, fuel-subsidized agriculture;
2. moist forests, shallow lakes, moist grasslands, avg. agriculture
3. grasslands, deep lakes, mountain forests, unsubsidized agriculture

Ecosystems need:

• Continuous input of high-quality energy
• Storage capacity
• Dissipative structures

Odum’s maximum power principle: ‘systems most likely to survive in this competitive world are those that efficiently transform the most energy into useful work for themselves and surrounding systems with which they are linked for mutual benefit.’

What about transfers of energy, predators?

• 10% rule—about 10% of total energy available at beginning will be available for next transformation
• According to Odum, ‘predators are relatively rare and energy-expensive componenets of ecosystems, but they may be very important in terms of feedback control of herbivores, which in turn may have a major effect on plant production.’

Concentration of solar energy—by plants, by fossilization, by electricity

human appropriation of photosynthetic capacity

• near 40%
• only about 4% for food, fiber, fuel for humans, animals
• Odum says at least 1/3 of primary production must be left for the ecosystem

What limits ecosystem growth?

• • Nutrients, chemicals (remember soil map)—N, P and K
  • Toxins (even salts—hydraulic societies)
  • Soil = clorpt (climate, organisms, relief, parent material, time)
  • Temperature, water, sunlight (think caves, lakes)
  • Photosynthetic capacity

Now, Enter humans . . .

Agricultural yields (and a looming ‘energy crisis’):

1. increased by mechanization, fertilizers, irrigation, pesticides (subsidies)

• • doubling crop input requires 10-fold increase in subsidies
  • between 1950-84, 250% increase in world grain production
  • 31% to make inorganic fertilizer; 19% for running machinery; 16% for transportation; 13% irrigation; 8% raising livestock (not feed); 5% for crop drying; 5% for pesticide production; 3% miscellaneous (think resource process)

(much of the following comes from Dale Allen Pfeiffer’s article, ‘eating fossil fuels‘)

2. plant selection (high-yield varieties, plant breeding—amount put into vegetation, seed production varies from wild to domesticated varieties)
3. ‘pre-industrial’ systems—obviously agrarian farming uses less energy subsidies, but has reasonable energy efficiencies
4. protein production is really a limiting factor for humans (meat is expensive—soybeans, amaranth, vs sugar cane, rice/wheat–protein content of staple crops varies)
5. livestock (produce five times the biomass of humans)
6. rangeland versus agriculture (the former is usually located on less productive land)
7. land-extensive agriculture (moving onto marginal lands—West Africa example–prime land, especially in the United States, may be converted into living space–urban sprawl, for example)
8. conversion of forest to agriculture (we need forestland too, by the way)
9. fish farming versus commercial fishing—oh, did you think your salmon was wild? Since 1970, fish farming or aquaculture has gone from 4% of fish ‘produced’ to over 27%.
10. depleted soils, pest problems—we must continue to increase energy subsidies just to maintain current productivity levels—we’ve reached diminishing returns. As urban growth displaces some of the most fertile soils, not only must societies use more ‘land extensive’ strategies (find new acreage/hectarage to cultivate), but they are generally less fertile soils, requiring either more energy subsidies, or more acreage in production.
11. modern industrial agriculture is unsustainable—it takes 500 yrs to produce one inch of topsoil, which can be lost in one nasty storm, especially with annual cropping that leaves soil largely exposed to the elements. Soil is eroding 30 times faster than it is being regenerated; aquifer depletion is occurring most everywhere as well, for instance the Ogallala Aquifer.
12. According to Pfeiffer, ‘Much of the soil in the Great Plains is little more than a sponge into which we must pour hydrocarbon-based fertilizers in order to produce crops.’ And we haven’t even mentioned the depletion of
13. cropland lost—2 million acres to erosion, salinization; 1 million to urbanization each year
14. agriculture consumes 85% of freshwater resources; less than .1% of ground water removed is replaced by rainfall
15. use of pesticides has increased 33 fold in two decades—yet we lose more to pests. Think about the role of evolution in this process–insect pests and other pathogens are prolific, and unless a pesticide kills them all, natural selection, or differential reproduction, quickly produces resistant strains, which has been a source of comfort to the petrochemical industry.
16. monocultures, no crop rotation, replacement of complex ecosystems with farms (of trees, fish, crops)—what has been the industrial response? Genetic engineering (oops! Wrong site). The answer to that torturously slow process of evolution.

the ‘other’ energy crisis—fuelwood is the main source of energy in the third world

• urban growth It’s happening, fueled by globalization, factory production, free trade zones, Western consumption, cheap labor, etc.
• increased demand for firewood in rapidly growing urban areas without major utilities systems
• poaching–the laws of supply and demand, combined with ambiguous property rights for farming villages, create opportunities for enterprising capitalists to sell fuelwood at unsustainable rates (forcing those who collect for household use, mostly women, to expend more of their own energy, walk further, etc.) at far below its market value–this is how Harrison’s ‘resouce crisis’ looks in poor countries
• cash economy, need for income–again, this creates the incentives to commercialize the fuelwood supply–who’s looking at conservation and supply issues?
• losses—to soil, moisture-holding, shade, habitat
• supply versus demand-side policies–again, how important is conservation of existing fuelwood resources, and production of new sources, and how does this fit with property rights and farming villagers’ control over their territories?

Ideas

That’s what the Drawdown book is all about …