This might be a bit of a mess of thoughts as I'm constantly readjusting my ideas but I'll try to write some of it down.
I think a very critical thing is having the right to land, without that it will be very difficult to live in a sustainable way. With control over land concentrated over a very small number of people it will simply be impossible for everybody to live sustainably without somehow taking that land out of the control of those few.
Simply looking at what we need, I view it to be warmth, shelter, food, community, entertainment
Let's start with warmth, let's look at the sustainable resources we have available. We create our own warmth from inside our body as a result of our constant metabolism, we can adjust how warm we are by putting on and taking off layers of clothing.
Clothing also needs to come from somewhere, eg animal skins, fibres such as hemp, flax, cotton etc, these different materials need to be carefully chosen as many have different implications in their use and in some places may be difficult to use sustainably. I'll just use any clothes I find really, there's a lot of things that I do that may not be sustainable in the long run but since they are byproducts of things that I am not contributing to I can justify them.
In the middle of winter it can be too cold for simple insulation to be enough, this is where I think it's important to look at earth-bermed and earthship style dwellings, dugouts etc, as the earth is at a constant 12C (varies depending on location of course) all year round once you get below a couple feet, so as long as you're willing to keep some layers on you can be pretty warm all year round.
If not, then I see wood as the main source of heat for cooking as well as heating, although this certainly needs to be done with a lot of care. If you're looking at mature forests, dead wood forms a very essential part of the ecosystem by hosting recyclers such as bugs and insects, which in turn birds etc feed on and it's quite an integral part of the support for wildlife in an area, so indiscriminately stripping an area of dead wood can be quite destructive. Dead standing trees are a better choice but still have to be taken with care.
It will often actually be better for everything around you to actually cut down one or two mature live trees, chop them up and properly season them until they are burnable. Good burners and insulated buildings can cut down on wood use a lot, open firepits while useful take up quite a bit of wood, though small pits no bigger than a foot across use less wood, this is where proper skills of living out in the woods for a while are absolutely essential to live in sustainable ways, although I'm very used to it it's amazing seeing visitors who've never really used fires before trying to light fires; they either totally fail and end up with a soggy mess, burn green wood or use fires that are far to large for the purpose they serve, but they learn quickly and it's a very useful skill to have.
Shelter can be made from a lot of different natural materials, keeping them waterproof is usually the hardest part; personally I still use plastic tarpaulins for the roofs of shelters as they are just the easiest waterproof way to do things, while they may not be sustainable in the long run if it's the only plastic I buy then I'd say it's a lot better than 'the average'. A general 'shed' style building is the easiest to make, but there's a lot of different designs such as treehouses, benders, yurts, tipis, dugouts etc etc, all with their own pro's and cons, again this just needs trying and experience and it's not really all that difficult. I see having shelters that are biodegradable as a very positive thing, even if it means rebuilding your home every few years I don't see a problem with it.
Food is really the main one, and it's quite complicated to actually figure out things that will work for everybody. A lot of people do say that the planet simply does not have enough resources to feed the number of humans on this planet sustainably, to be honest I'm not really sure but to live sustainably while nourishing and being one with sustainable ecosystems there will probably have to be less people on the planet in simple terms of land use, although with different techniques it may be possible to feed everybody, I simply do not know.
A list of food sources I can think of, then I'll talk about some of them.
Growing plants
Foraging
Hunting
Scavenging
Domesticating animals
Fishing
Growing plants is what I see to be a major part of my food source, but I acknowledge that it can not always be relied on. Even with the best skills some years may have worse weather than others, crops can and do fail and diseases can come along and wipe out huge portions of the food that you rely on.
Permaculture is very important imho, and beyond just the growing food aspect of it, I guess permaculture is what I'm talking about for all of this. But it needs work for different ecosystems, for example nut trees really don't grow very well in the scottish highlands, and forest gardening can be very difficult there as it encourages a high humidity inside the system which leads to a lot of good food rotting, these techniques need developing for all ecosystems and bioregions.
Failing the very 'continuous' theories of forest gardening and similar things, I oppose the use of chemical fertilisers, pesticides, herbicides, plowing and deforestation in order to grow food. Crop rotation and the appropriate use of natural fertilizers such as seaweed, animal manure (where appropriate of course), urine and composted human feces, other natural plants such as comfrey and the appropriate use of leaf mulch and forest humus can take the role of fertilisation and hopefully the continuous improvement of soil nutrients over time.
Nice plants to grow: peas, beans, nuts (where you can), fruit trees, lettuces and other brassicas, root crops such as potatoes and parsnips.
Foraging I believe can take a small but important part in our diet, mainly from fruit trees and berries which can give us important nutrients and minerals, but for example even nettles can provide quite a lot of protein year round if the bushes are kept cut back well. Over time you can develop a knowledge of what plants are edible, which are the highest in nutrients and how to harvest and cook them, again this needs experience.
Hunting is a bit difficult for me, as for now I do follow veganism, but I do recognize that (as before said), crops do fail etc etc and it may be difficult to get a properly complete diet without small amounts of meat. For example in the scottish highlands deer are very common around, and although I would wish to say that we could just let them roam wild and never shoot them, they would soon become as common as the sheep which have totally decimated the whole of the beautiful bioregion of the caledonian forests and turned the hills into bare vistas of grass and heather, so I see shooting small amounts of deer and only as much as is absolutely necessary as being possible in a sustainable future; I also see a difference in terms of environmental and "animal rights" 'factors' between ending the life of an animal when you really need the food from it's own natural environment where it has lived all of it's life without domestication or control from humans and the alternative which would be farming non native animals on land under constant control and cruelty from humans; it's not ideal but it may be necessary.
Scavenging is probably a pretty small part but worth mentioning, I mean finding dead animals and putting their energy to use in your body, recycling the nutrients and continuing their life. As an example I would say I'm vegan but I will occasionally eat roadkill meat (last weekend had some roadkill deer cooked in a maori style earth oven, amazing), and don't see anything wrong with it really. Or scavenging in terms of eating from the bins of establishments such as supermarkets etc, all the food is going to landfill anyway so I view it as a good thing, while not really sustainable in the long run it is a good food source that many people do live off of all year round.
Domesticating animals is something I am really against so I won't say much about it but the reasons why: I view animals as free spirits and confining them with fences, controlling their diets and environments, raising them for the only reason to have food for us as a negative and spiritually unsustainable thing, and however you raise them they will have a negative impact on the ecosystem; whether it's through the large inefficiency in grain-fed animals or the destruction of land (a lot more than just with farming food) with grazing animals I see them as a negative impact.
Fishing I have a similar opinion on as hunting, just to say that ocean ecosystems are in general quite well balanced and great care must be taken not to overfish, however pole and line fishing probably won't have that huge an impact as long as it is done sensibly and with care.
I'll do a quick summary of the community and entertainment; I'm not really sure if there is 'one way' in which we are supposed to live, but personally I love living in a communal almost 'tribal' way, it spreads the necessary tasks between people and makes life a lot easier to live; for example if you have 1 person they have to cook every single meal for themselves, if you have a 'tribe' of 30 people then each person would only have to cook once a month if shared evenly, and it's barely any more effort cooking for 30 people than it is one, not to mention a lot more efficient on resources such as firewood.
Entertainment is also a very important one and one that should not be neglected, I also mean in sustainability of mental and spiritual health, I believe that people can make their own entertainment and help each other with it, and I oppose the concentration of entertainment onto mass media and disconnection from the person and the situation they are in.
Hope this provides a bit of insight, and it doesn't just disappear into the ether, thanks
