Thank you. My question doesn't relate to avoiding salt buildup in the soil, though. I am asking about ways to facilitate gas exchange at the root zone in soils that lack proper aeration for this to happen passively. Since the act of watering displaces soil gasses, pushing out what is already there and drawing in fresh oxygen behind the water, I was curious if watering on a more frequent schedule than necessary would help mitigate the lack of passive gas exchange. Of course, you would have to manually drain the PWT each watering. There seem to be two benefits of a highly aerated container soil, from what I have read and understood so far, and they are closely related: 1. Reduces or eliminates areas that allow no gas exchange (the dreaded PWT - waterlogged areas with insufficient oxygen available for roots to respire) 2. Reduces or eliminates areas that allow insufficient gas exchange (compacted areas where the available oxygen is quickly used up and the other gasses, byproducts of root respiration, end up trapped instead of being able to diffuse out to allow new oxygen in). Now, 1. can be addressed, in part or completely, by the methods described in this thread. Ways to manually drain the soil's PWT when the soil is too dense for it to drain away passively. Are there similar strategies for dealing with 2. manually when a soil is too dense for reasonable gas exchange to occur passively? Will a more frequent watering schedule act as a manual gas exchange?

Great discussion all around. Appreciate everyone's viewpoints & contributions. Kinda busy, but a couple of quick thoughts: As others say, I don't think we are going to significantly de-industrialize any time soon - hopefully we can move quickly towards doing it smarter. I'm not totally opposed to industry or economy of scale ...but we've got to learn to do it with more closed-loops, better designs that turn our problem 'wastes' into resources, etc. We have the know-how of how to meet our basic needs and restore ecological health. We know how to regreen the desert (Geoff Lawton) or restore degraded pasture land while grazing MORE animals (Allan Savory) - As Olpea pointed out, the political will isn't there. So much inertia built up in this approaching-train-wreck of an economic system. How much crappier do things have to get before the growth-at-all-costs nonsense gets tossed? While the rest of the world is figuring that out that growth at all costs, I work on facing up to my own consumption, which is humbling. I am doing my best to withdraw from 'feeding the beast', growing what I can at home, saving and sharing seed & seedlings. Buying what I can't grow from local & organic producers. Most of all, my wife and I just refuse to live a consumerist lifestyle. I laugh every time I take out the garbage because there really is so little of it. We could easily go a couple months without taking out the trash, the next step is cutting down on the recyclables. No-till: Fukuoka did it to good effect with rice, equalling yields of his counterparts using 'green revolution' approaches. There are pockets of Japanese farmers here and there quietly using Fukuoka's method. Hopefully, I'll have the chance to visit one of these farms next time I visit Japan. In the west, I have heard of a lot of people experimenting with no-till or perennial grains, interesting glimpses, but no stunning successes. After a few thousand years of breeding annual grains for till systems, it's not surprising that progress might take a few generations. John Jeavon's biointensive offers small-scale grain production which builds biomass every year, but that is backyard scale - beds double dug by hand. There are many different growing systems out there that will bring high yields without undermining future ability to produce. I don't think there are any one-size-fits-all solutions, but different for each situation. Lastly, I have to emphasize that, despite occasional differences of opinion, I think horticulturalists and farmers, conventional or organic, are some of the best people on earth.

I have a 8hp tecumseh on my snowblower, 10hp Briggs intek on my chipper, 18hp Briggs Vangauard on my generator, a 25hp Kohler Command on my tractor and a honda 5hp lawnmower. All start easy and run great. None of them burn oil. The honda is the quietiest but also has a biggest muffler compared to the others. I will say that I'm disappointed in the honda mower. The underside of my deck is completely rust. I also had to replace the cable to engage the tranny, but had to buy the whole assembly as a kit to get the cable. My deck clogs easily whether I use mulching blades or regular blades and the cut isn't that great. The engine my be great, but the rest of the mower is not worth the 400 paid for it. With proper car, air filter changes, oil changes, new spark plugs, and good gas, any engine will last a long time. I know a lot of people that just put gas in and go. Then the engine breaks and the equipment is the biggest piece of junk. For the average homeowner, I don't think the engine should be of a concern. I think the unit its mounted too should be of more importance.

The latest is of the journal Science is devoted to hydrogen as a fuel and to other aspects of the energy equation. I've appended the titles; for access to full articles, you must be a subscriber. In the meantime, I'll post the series' editors introduction. ------------------------------------------------------------ Not So Simple Robert Coontz and Brooks Hanson Seen up close, hydrogen looks like a recipe for success. Small and simple--one proton and one electron in its most common atomic form--hydrogen was the first element to assemble as the universe cooled off after the big bang, and it is still the most widespread. It accounts for 90% of the atoms in the universe, two-thirds of the atoms in water, and a fair proportion of the atoms in living organisms and their geologic legacy, fossil fuels. To scientists and engineers, those atoms offer both promise and frustration. Highly electronegative, they are eager to bond, and they release energy generously when they do. That makes them potentially useful, if you can find them. On Earth, however, unattached hydrogen is vanishingly rare. It must be liberated by breaking chemical bonds, which requires energy. Once released, the atoms pair up into two-atom molecules, whose dumbbell-shaped electron clouds are so well balanced that fleeting charge differences can pull them into a liquid only at a frigid -252.89 Celsius, 20 kelvin above absolute zero. The result, at normal human-scale temperatures, is an invisible gas: light, jittery, and slippery; hard to store, transport, liquefy, and handle safely; and capable of releasing only as much energy as human beings first pump into it. All of which indicates that using hydrogen as a common currency for an energy economy will be far from simple. The papers and News stories in this special section explore some of its many facets. Consider hydrogen's green image. As a manufactured product, hydrogen is only as clean or dirty as the processes that produce it in the first place. Turner (p. 972) describes various options for large-scale hydrogen production in his Viewpoint. Furthermore, as News writer Service points out (p. 958), production is just one of many technologies that must mature and mesh for hydrogen power to become a reality, a fact that leads many experts to urge policymakers to cast as wide a net as possible. In some places, the transition to hydrogen may be relatively straightforward. For her News story (p. 966), Vogel visited Iceland, whose abundant natural energy resources have given it a clear head start. Elsewhere, though, various technological detours and bridges may lie ahead. The Viewpoint by Demirdöven and Deutch (p. 974) and Cho's News story (p. 964) describe different intermediate technologies that may shape the next generation of automobiles. Meanwhile, the fires of the fossil fuel-based "carbon economy" seem sure to burn intensely for at least another half-century or so [see the Editorial by Kennedy (p. 917)]. Service's News story on carbon sequestration (p. 962) and Pacala and Socolow's Review (p. 968) explore strategies--including using hydrogen--for mitigating their effects. Two generations down the line, the world may end up with a hydrogen economy completely different from the one it expected to develop. Perhaps the intermediate steps on the road to hydrogen will turn out to be the destination. The title we chose for this issue--Toward a Hydrogen Economy-- reflects that basic uncertainty and the complexity of what is sure to be a long, scientifically engaging journey. ============================================================ SPECIAL ISSUE: Toward a Hydrogen Economy --------------------------------------------------------------------------- Toward a Hydrogen Economy: Introduction to special issue -------------------- Not So Simple Robert Coontz and Brooks Hanson http://www.sciencemag.org/cgi/content/summary/305/5686/957?etoc p. 957 Toward a Hydrogen Economy: News -------------------- The Hydrogen Backlash Robert F. Service http://www.sciencemag.org/cgi/content/summary/305/5686/958?etoc p. 958 The Carbon Conundrum Robert F. Service http://www.sciencemag.org/cgi/content/summary/305/5686/962?etoc p. 962 Choosing a CO2 Separation Technology Robert F. Service http://www.sciencemag.org/cgi/content/summary/305/5686/963?etoc p. 963 Fire and ICE: Revving Up for H2 Adrian Cho http://www.sciencemag.org/cgi/content/summary/305/5686/964?etoc p. 964 Will the Future Dawn in the North? Gretchen Vogel http://www.sciencemag.org/cgi/content/summary/305/5686/966?etoc p. 966 Can the Developing World Skip Petroleum? Gretchen Vogel http://www.sciencemag.org/cgi/content/summary/305/5686/967?etoc p. 967 Toward a Hydrogen Economy: Viewpoint -------------------- Sustainable Hydrogen Production John A. Turner http://www.sciencemag.org/cgi/content/abstract/305/5686/972?etoc p. 972 Hybrid Cars Now, Fuel Cell Cars Later Nurettin Demirdoven and John Deutch http://www.sciencemag.org/cgi/content/abstract/305/5686/974?etoc p. 974 Toward a Hydrogen Economy: Review -------------------- Stabilization Wedges: Solving the Climate Problem for the Next 50 Years with Current Technologies S. Pacala and R. Socolow http://www.sciencemag.org/cgi/content/abstract/305/5686/968?etoc p. 968 ---------------------------------------------------------------------------