This is one of many very interesting videos available on the internet about 'permaculture'. In brief this is a set of principles that can guide how we live (and perhaps especially known for producing food in a more ecological way) based on understanding and working with the natural world, rather than against it.
I will be posting a lot more on this useful approach, but for those who are new to it, here is an interesting example. A walk round the mountain farm established by Sepp Holzer and here presented by his son. Sepp Holzer's Mountain Permaculture Farm