Note that each module in the Qualification -Certificate in Environmental Sustainability is a short course in its own right, and may be studied separately.
There are many different ways people go about achieving greater sustainability on their property. The following are just some examples:
Natural farming works with nature, rather than against it. It recognises the fact that nature has many complex processes which interact to control pests, diseases and weeds and to regulate the growth of plants. Chemicals, such as pesticides and artificial fertilisers are being used more and more, even though they can reduce both the overall health of the environment and the quality of farm produce.
Undesirable long-term effects such as soil degradation and imbalances in pest-predator populations also tend to occur. As public concern grows these issues are becoming increasingly important. Farming the natural way aims to ensure quality in both the environment in which we live and in the produce we grow on our farms. There are a variety of ways of growing plants that work with nature rather than against it. Some are techniques that have been used for centuries. Some of the most effective and widely used methods are outlined here.
Organic farming has been given a variety of names over the years - biological farming, sustainable agriculture, alternative agriculture, to name a few. Definitions of what is and isn’t ‘organic’ are also extremely varied.
Some of the most important features of organic production, as recognised by the International Federation of Organic Agriculture Movements (IFOAM), include:
· Promoting existing biological cycles, from micro-organisms in the soil to the plants and animals living in and on the soil.
· Maintaining the environmental resources locally, using them carefully and efficiently and re-using materials as much as possible.
· Not relying heavily on external resources on a continuous basis.
· Minimising any pollution both on-site and leaving the site.
· Maintaining the genetic diversity of the area.
Practices which are typical of organic systems are composting, intercropping, crop rotation and mechanical or heat-based weed control. Pests and diseases are tackled with naturally-produced sprays and biological controls (e.g. predatory mites). Organic farmers generally avoid the use of inorganic (soluble) fertilisers and synthetic chemical herbicides, growth hormones and pesticides.
One of the foundations of organic farming, linking many other principles together, is composting. Bacteria and worms act to break down the waste products by skilfully combining different materials, balancing carbon and nitrogen levels and blending coarse and fine ingredients,.
Composting produces a valuable fertiliser that can be returned to the soil. Natural biological cycles are promoted, ‘wastes’ are re-used and the need for external supplies of fertiliser are reduced or cut altogether.
In the strictest sense Permaculture is a system of production based on perennial or self‑perpetuating plant and animal species which are useful to people.
In a broader context, Permaculture is a philosophy which encompasses the establishment of environments which are highly productive and stable and which provide food, shelter, energy, etc., as well as supportive social and economic infrastructures. In comparison to modern farming techniques practised in Western civilisations, the key elements of Permaculture are low energy and high diversity inputs. The design of the landscape, whether on a suburban block or a large farm, is based on these elements.
A Permaculture system can be developed on virtually any type of site, though the plants selected and used will be restricted by the site’s suitability to the needs of the varieties used. Establishing a Permaculture system requires a reasonable amount of pre-planning and designing.
Factors such as climate, landform, soils, existing vegetation and water availability need to be considered. Observing patterns in the natural environment can give clues to matters which may become a problem later, or which may be beneficial.
A well designed Permaculture farm will fulfil the following criteria:
· Upon maturity it forms a balanced, self-sustaining ecosystem where the relationships between the different plants and animals do not compete strongly to the detriment of each other. The farm does not change a great deal from year to year but it does never the less still continue to change
· It replenishes itself. The plants and animals in the farm feed each other, with perhaps only minimal feed (e.g. natural fertilisers) needing to be introduced from the outside.
· Minimal, if any, work is required to maintain the farm once it is established. Weeds, diseases and pests are minimal due to companion planting and other natural effects which parts of the ecosystem have on each other.
· It is productive. Food or other useful produce can be harvested from the farm on an ongoing basis.
· It is intensive land use. A lot is achieved from a small area. A common design format used is the Mandala Garden, based on a series of circles within each other, with very few pathways and easy efficient watering.
· There is a diverse variety of plant types used. This spreads cropping over the whole year so that there is no time when a "lot" is being taken out of the system. This also means that the nutrients extracted (which are different for each type of plant or animal) are" evened out" i.e. one plant takes out more iron(Fe) ,while another plant next to it takes out less iron and so iron does not get depleted because then not all of the plants have a high iron demand. The diversity of species acts as a buffer, one to another.
· It can adapt to different slopes, soil types and other microclimates.
· It develops through an evolutionary process changing rapidly at first but then gradually over a long period ‑ perhaps never becoming totally stable. The biggest challenge for the designer is to foresee these ongoing long term changes
Structure of a Permaculture System
· Large trees dominate the system. The trees used will affect everything else ‑they create shade, reduce temperature fluctuations below (create insulation), reduce light intensities below reduce water loss from the ground surface, act as a wind barrier, etc.
· In any system, there should also be areas without large trees.
· The “edge” between a treed and non-treed area will have a different environment to the areas with and without trees. These “edges” provide conditions for growing things which will not grow totally in the open no in treed areas. In the Southern Hemisphere, the north edge of a treed area is sunny but sheltered, while the south edge is cold but still sheltered more in the open" Edges" are an example of microclimates i.e. small areas within a larger site that have special conditions which favour certain species which will grow well elsewhere.
· Pioneer plants are used initially in a Permaculture system to provide vegetation and aid the development of other plants which take much longer to establish. For example, many legumes grow quickly and fix nitrogen, i.e. raise the nitrogen level in the soil, and thus increase nutrients available to trees and other plants growing beside them .Over time the tall trees will become fully established and then shad out the lower growing plants especially the Pioneer plants that helped to stabilise the area. Pioneer plants are usually, but not always, short lived.
Cultivation of soil is often used extensively in organic growing, particularly to control weed growth.
Where chemical herbicides are not used, ploughing or hoeing can be extremely effective methods of controlling weeds. These techniques also help to open up soils which have become compacted, allowing water and air to penetrate more readily into the soil. Cultivation has been shown (by ADAS research, U.K.) to help reduce plant disease by destroying plants which might harbour those diseases that also invade the desirable crops.
There are problems with cultivation however, as outlined below:
· It can destroy the soil profile, the natural gradation from one type of soil at the surface (usually high organic and very fertile) through layers of other soil types as you go deeper in the soil. When the soil profile is interfered with, hard pans can be created. A pan is a layer beneath the surface of the soil where water and root penetration becomes difficult. Water can build up over a hard pan creating an area of waterlogged soil.
· Drainage patterns can be changed.
· Plant roots can be damaged.
· Heavy machinery can cause compaction, especially in wet conditions. The tyres are the area that courses the most compaction due to the large weight compressed on to a small tyre tread area.
· Shallow cultivation can encourage weed seed germination. Cultivation can also bury seed and protect it from foraging birds and rodents. It may also help keep it moist and warm enough to germinate.
· Loosened soil can be more subject to erosion (e.g. from wind, rain, irrigation).
No Dig Techniques
There are obvious advantages to be had by using techniques which do not dig or cultivate the soil. Some of the techniques are pest, disease and weed control with fire, mulching for weed control and water retention and raised organic beds.
Vegetable-Sod Inter planting
This involves growing mulched rows of vegetables 20-40cm (8-15 in) wide over an existing mowed turf. A narrow line may be cultivated sometimes down the centre of each row to sow seed into, if growing by seed, to hasten germination. Mulch mats, black plastic, paper or organic mulches can be used to contribute to weed control in the rows. Crop rotation is usually practiced between the strips. This contributes towards better weed control. Clover is often encouraged in the strips of turf between rows to help improve nitrogen supplies in the soil.
No Dig Raised Beds - One Method
Build four walls for each bed from timber. Use a wood which will resist rotting such as red gum, jarrah, recycled railway sleepers or even treated pine.(or some local rot resistant timber) The dimensions of the box can be varied but commonly might be 20-30cm (8-12 in)or more high and at least 1 metre (3.4 ft) wide and 1-3 metres (3.4-10 ft) or more long.
The box can be built straight on top of existing ground whether pasture, bare earth or even a gravel path. There should be a little slope on the ground it is built over to ensure good drainage. It may also be necessary to drill a few holes near the base of the timber walls to ensure water is not trapped behind them. Weed growth under and around the box should be cleaned up before building the box. This may be done by burning, mowing, hand weeding, mulching, or a combination of techniques.
Once built, the box can be filled with good quality organic soil, compost, or some other soil substitute such as alternate layers of straw and compost from the compost heap or alternate layers of graded and composted pine bark, manure and soil. The growing medium must be friable, able to hold moisture, and free of disease and weeds (avoid materials, such as grass hay, or fresh manures that may hold large quantities of weed seeds).
A commonly used watering technique in these beds is to set a 2 litre (3.5 pint) plastic bottle (eg. soft drink or milk) into the centre of the bed below soil level. Cut the top out, and make holes in the side. This can be filled with water, which will then seep through the holes into the surrounding bed. Mulching the surface may be desirable to assist with controlling water loss and reducing weeds (Ref: Organic No Dig, No Weed Gardening by Pincelot, publisher Thorsons).
Biodynamic farming and gardening is a natural practice which developed from a series of lectures given by Rudolf Steiner in 1924. It has many things in common with other forms of natural growing, but it also has a number of characteristics which are unique. It views the farm or garden as a “total” organism and attempts to develop a sustainable system, where all of the components of the living system have a respected and proper place.
There is a limited amount of scientific evidence available which relates to biodynamics. Some of what is available suggests biodynamic methods do in fact work! It will, however, take a great deal more research for mainstream farmers to become convinced widely of the effectiveness of these techniques; or in fact for the relative effectiveness of different biodynamic techniques to be properly identified.
Principles of Biodynamics:
· Biodynamics involves a different way of looking at growing plants and animals.
· Plant and animal production interrelate.
· Manure from animals feeds plants. Plant growth feeds the animals.
· Biodynamics considers the underlying cause of problems and attempts to deal with those causes rather than dealing with superficial ways of treating problems. Instead of seeing poor growth in leaves and adding nutrients; biodynamics considers what is causing the poor growth -perhaps soil degradation, wrong plant varieties etc. It then deals with the bigger question.
· Produce is a better quality when it is “in touch” with all aspects of a natural ecosystem. Produce which is produced artificially (e.g. battery hens or hydroponic lettuces) will lack this contact with “all parts of nature”, and as such the harvest may lack flavour, nutrients and not be healthy food.
· Economic viability and marketing considerations affect what is grown.
· Available human skills, manpower and other resources affect what is chosen to be grown.
· Conservation and environmental awareness are very important.
· Soil quality is maintained by paying attention to soil life and fertility.
· Lime, rock dusts and other slow acting soil conditioners may be used occasionally.
· Maintaining a botanical diversity leads to reduced problems.
· Rotating crops is important.
· Farm manures should be carefully handled and stored.
Biodynamics believes there is an interaction between crop nutrients, water, energy (light, temperature), and special biodynamic preparations (i.e. sprays) which result in biodynamically produced food having particularly unique characteristics.
Plant selection is given particular importance. Generally, biodynamic growers emphasise the use of seed which has been chosen because it is well adapted to the site and method of growing being used.
“Moon planting” is often considered important. Many biodynamic growers believe better results can be achieved with both animals and plants if consideration is given to lunar cycles. They believe planting, for example, when the moon is in a particular phase - can result in a better crop.
Developing A Biodynamic Farm or Garden
The first step is always to look at the property as a single organism, and to appreciate that whatever changes are made to the property can have implications to many (probably all) of the component parts of that property. There is an obvious (though sometimes subtle) relationship between every plant or animal and its surroundings, both the nearby and the more distant surroundings.
These are a particularly unique and important aspect of biodynamics. There are all sorts of biodynamic preparations. There is a wide experience (throughout many countries) which suggests the use of these preparations is beneficial, resulting in both morphological and physiological changes in plants (e.g. better ripening rates, better dry matter, carbohydrate and protein rates).
Two different sprays (500 and 501) are commonly used. These are made from a precise formulation of quartz and cow manure and are sprayed on crops at diluted rates. Biodynamic growers also use preparations made from plants to stimulate compost and manure heaps.
Cow manure is placed in a cow horn and buried over winter, with the intention of maintaining a colony of beneficial organisms in the horn over the cold months which can then recolonise the soil quickly in the spring.
Insect control sprays are commonly made as follows:
Catch some of the grubs or insects which are becoming a pest. Mash them to a pulp (perhaps in a food processor), then add water and place in a sealed jar for a few days in a refrigerator.
Once fermentation begins, remove and dilute with water (100:1). Spray over affected plants. This is said to repel the insects, though no scientific evidence is known to support the treatment.
Biodynamic growers use a variety of different preparations to add to compost heaps or spray on paddocks or garden plots to encourage faster decomposition. Preparations have included: Yarrow flowers, Valerian flowers, Oak bark, Calendula flowers, Comfrey leaves and preparations from Casuarina and Allocasuarina species