Myron Platte wrote:
I’m sorry, not high, rich. There is a huge difference between presence and availability, in terms of minerals. Calcium presence often correlates with alkalinity, but the further the soil ph is from 6.4 in either direction, (and depending on a few other factors) the less available more elements are. That includes calcium. Some plants have the ability to reach through a trapdoor, so to speak, and absorb specific nutrients that are unavailable. This gives them a huge advantage over plants that do not have this ability in places where those nutrients are unavailable. When parts of the plant rot on top of or in the ground, the calcium is returned, in a bioavailable form. This leads to the plant slowly making itself obsolete in one or another area.
Myron Platte wrote:Bindweed indicates very low calcium, phosphate, low humus, poor residue decay, good drainage, and very high potash and magnesium. .
David Wieland wrote:[
I don't know where the idea of disassembling a mountain comes from. Certainly mining is involved in some way with practically everything we have, even if it's just digging up clay to make bricks or cob. We wouldn't be sustainable without it.
As for perlite, mountain disassembly is hyperbole. Here's a description from a gardening website:
Perlite is a volcanic glass that is heated to 1,600 degrees F. (871 C.) whereupon it pops much like popcorn and expands to 13 times its former size, resulting in an incredibly lightweight material.
(Read more at Gardening Know How: What Is Perlite: Learn About Perlite Potting Soil https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/perlite-potting-soil.htm)
The Three Rs practice is good but not enough to sustain us. It certainly can't build a thrift shop, for example.
David Wieland wrote:
Andrew Sackville-West wrote: What does "sustainable item" mean?
Not sure I can answer completely, but part of clothing being sustainable is what was utilized in the manufacture... There was a phase where "stone washed" was "in". Stone washed jeans and stone washed shirts and blouses. The stones were a kind of light weight and abrasive mineral being mined.... maybe something like perlite. The question is whether it is sustainable to disassemble a mountain for this "stone". If the dyes being used to dye the fabric are toxic and result in pollution of streams rivers and ocean, that's probably not sustainable. It is hard work to know these things about commercial products, and especially when the industry and regulatory agencies collaborate in obscuring the information from the buyer.
One other thing is the conditions of the workers who made the clothes. Are they paid a living wage? Is it a sweat shop. The abuse of humans isn't sustainable. It's short term for the laborers and the exploiters.
I think shopping at second hand and thrift shops is more sustainable than new, because IMO, of the three Rs reduce reuse recycle the re-use is the most effective at impacting the waste stream.
John C Daley wrote:
One last thing: engineers and design professionals don't necessarily know as much as they would like you to believe they do. The desire for a guarantee from them is going to inspire them to overbuild. Try to find a person with a lot of practical experience and a willingness to discuss the project, and who is not offended if you ask her /him to talk the variables through.
As a Civil Engineer I want to shoot back here.
- Civil Engineers are taught a lot and also taught how to research and observe.
- In specific areas Civil Engineers learn a lot from overseers who work the ground more regularly.
- Over building will always occur with ground works if a guarantee is expected, since the variables are many.
- In my experience I have not met and Engineer who will not talk through variables.
The biggest issue for me is landowners who have fixed ideas, a tiny budget that is not suitable for the problem and no ongoing plans for maintenance.
The second one is landowners who have mates that know everything, but take no responsibility for being wrong.