Biological Basis of Sustainable Communities
Sustainable communities are based on the principles of sustainability as found in nature. Natural ecosystems are communities of animals, plants and micro-organisms. These interact benevolently, along with all the non-living components, such as light, temperature and moisture, to form stable communities, whereby plants, animals and micro-organisms are able to satisfy their own needs, as they contribute to other’s needs. The richness, stability and resilience of an ecosystem depend very much on the diverse numbers of species, or biodiversity, within it.
Human beings are biological organisms that have adapted to their environment over perhaps millions of years, and all have real biological needs to be met. Human health, wellbeing and survival within an ecosystem all depend on that ecosystem’s health, wellbeing and survival. Those ecosystems with greater biodiversity are more robust and resilient against human disruption and degradation than those having less biodiversity.
To maintain long-term ecosystem health and well-being, renewable resources must be able to be replenished or regenerated, and non-renewable resources need to be reused or recycled, so that the whole system maintains integrity and equilibrium.
Sustainable Agriculture Principles
Sustainable gardening and farming are particularly suited to sustainable communities, and can make the community more of an ecological wonderland, where the soil will stay fertile, the creeks, rivers and dams will remain unpolluted, the organisation will not need to go into increasing debt, and the community will be more protected from the vagaries of climate and weather.
This can be achieved by living on a property:
- without diminishing natural resources, including soil, creeks, lakes and groundwater;
- without depending on expensive, off-property inputs, eg chemical fertilisers &, sprays;
- without using toxic substances, harmful to farm workers, neighbours, or consumers;
- without entering into debts that rely upon auspicious climate, weather, and market conditions for success and repayment.
And instead improving the property by:
- enriching soil by applying mulch, compost, and growing green-manure crops.
- growing a diversity of produce, to protect soil and lessen marketplace vulnerability;
- using a renewable seed base of many varieties, that may be maintained on the land;
- protecting the farm from climate and weather by growing trees for food, shelterbelts, shade, fodder, drought protection, nitrogenation, desalinisation, and wildlife corridors.
Organic gardening is aimed at producing healthier, tastier and more nourishing food on a sustainable basis without damaging the environment or depleting the soil. To achieve this organic farmers look primarily to improve the quality of the soil by feeding it compost to make it rich and fertile, ensuring it has good texture and structure and by keeping it free of all artificial and chemical contaminants.
Organic gardening is an often-favoured pastime or occupation, a wonderful way to relate to the earth, and ensures topsoil gets richer and deeper every year, which yields easy and luxuriant plant growth, a major principle of sustainability. Proper gardening not only nourishes the earth and feeds the people, but it also makes the community a beautiful place and creates a peaceful, healing atmosphere. Organic gardening, biodynamics and permaculture are practiced for:
- producing nutritious, healthy food,
- connecting people with the earth;
- making optimal use of the land;
- healing the land;
- living without pollution or ecological destruction.
Soils are the foundation of virtually all plant life, and are another biological wonder. Soil fertility is improved by increasing the amount of organic matter in the soil by:
- adding compost made from weeds, manures, food scraps, straw and other forms of organic matter;
- using mulch to cover soil around plants and trees;
- encouraging the activity of soil microbes, worms and beneficial insects;
- growing mixed crops of companion plants;
- rotating monocrops to give the soil exposure to a variety of plants;
- growing and slashing ‘green manure’, nitrogen-fixing crops;
- minimising tillage or other disruptions to soil structure.
In general, the less that soil is disturbed, the better the micro-organisms will process organic matter into humus. Although to begin with, we may have to aerate the soil and do minor other things to get this process under way.
Nature’s final expression of soil is humus, a jelly-like colloid contained in topsoil, which improves soil by:
- balancing soil porosity, making sand more water retentive, and clay more pervious;
- improving friability, aeration and water absorbing capacity of the soil;
- decreasing erosion and compaction, by binding soil to itself;
- modifying temperature extremes, with its insulating properties;
- providing complex, nutrition rich foods for plants.
Compost is pre-digested plant food, rich in organic matter, and on its way to becoming humus. Compost is made from manures, grass clippings weeds and other high nitrogen matters, along with rather higher proportions of straw, sawdust and other organic vegetable matter high in carbon. When mixed together with the right amounts of air and water, the mixture cooks, killing weed seeds and harmful bacteria. Turning it over every 2-3 weeks keeps the process happening. When mixed into soil or spread under mulch, compost becomes invaded by worms, ready to assist micro-organisms in the next stage of creating humus.
Mulch is used as a soil cover around plants, primarily to hold in moisture, prevent weed growth, protect from extremes of heat and cold and to add to the organic matter in the soil. The best mulch is undoubtedly lucerne hay, rich in nitrogen and nitrogen-fixing bacteria, but almost anything, even stones or sheets of plastic, will fulfil at least some of the above requirements of mulch.
Strong, healthy plants are not so prone to attack, because diseases and fungi always infest the weaker, unhealthy plants, bringing nutrients to the soil and eventually producing further plant food. By diversifying the types of crops in a patch, and by rotating single crops each growing season, insects are not so inclined to swarm. Growing the species of plants that they like to settle on, such as the umbrelliferae, or parsley family can attract predator insects, which consume pest insects.
Organic farming does not include chemical fertilisers or the use of poisonous sprays such as herbicides, fungicides or pesticides. Many of these have been found to be far more toxic and residual than their labels indicate, and may penetrate the skin of the fruit into the edible flesh causing various illnesses to consumers. Many have been found to be highly toxic to farm workers, who may absorb chemicals through their skin or breathe in fumes.