Biochar Production, Application and Benefits Part One: Karry Fisher-Watts

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1 13 October 2016 Biochar Production, Application and Benefits Part One: Karry Fisher-Watts Key Points Biochar applied to acidic soils can improve agricultural productivity. The byproducts of biochar production can be used in a range of differing applications and purposes. Biochar remains in the soil for many years. The materials used to make biochar are organic in nature and, depending on the situation, can include tree waste, wood and wood products, crop residues, straw, rice husks, bamboo and animal dung. Introduction The potential of charcoal, in the form of biochar, to enhance soil fertility, while restoring carbon to the soil, has recently gained considerable attention. Pointing to the Terra Preta soils of the Amazon, man-made dark earths which were enriched with char more than 1,500 years ago, supporters cite the high fertility these soils have even today. The actual chemistry of these char residues, however, has only recently been investigated. Their stability and fertility may be related to protective habitats their internal spaces provide for microbes, or to char s molecular structure, which creates a large chemical exchange capacity (the ability to hold trace elements needed for plant nutrition). Although biochar has not, as yet, been extensively studied, research suggests that biological carbon converted to biochar can sequester about 50 per cent of its initial carbon in the soil for long periods, leading to a more stable and long-lasting soil carbon than would be the case from direct land application of uncharred carbon. Ms Karry Fisher and her husband Barry Watts own and manage a bush-foods and apiary business from Perth and their property in the upper Great Southern Region of Western Australia. In October 2013, Karry and Barry purchased a two-hectare block at Brookton, located 140 kilometres south-east of Perth. They named the property Treōwstede, a word derived from the Anglo-Saxon period which

2 translates to treed place. Their goal was to establish a sandalwood and bush-foods plantation. They were unaware at the time of purchase however, that the soil contained high salt levels and suffered other general fertility degradation challenges that had to be overcome. Karry and Barry have embraced the mammoth task of rehabilitating their property with a combination of scientific advice, a lot of creative thinking and hard work. They hope to bring life back to the land that has been badly degraded through poor farming practices. Ultimately, they aim to build new healthy fertile soils, which leave an enduring legacy where native flora and fauna can thrive. In time, they expect to be managing a profitable business while helping to offset carbon emissions, reduce environmental pollution, lower the water table and remediate the impact of dryland salinity through their natural farming practices. FDI recently took the opportunity to interview Karry to discuss her use of biochar as a way to enhance the fertility of her property using activated biochar and wood vinegar. Figure 1: Biochar produced from organic matter. Source: Hans Erken, Flickr. Page 2 of 6

3 Commentary FDI: What is biochar and how is it produced? What is the economic value of biochar? KF-W: The production and use of charcoal has a long history, with a variety of uses around the planet. These ranged from simple cooking, domestic heating in the early stages and being used later in early metalwork production of copper implements for commercial use from the iron age to modern day. In South America, the early use of charcoal was to make black paint. It was also made into a fine powder and used as part of a process for making small metal objects encased in clay and fired. Importantly, research is uncovering the use of Biochar in broad acre agriculture in the Amazonian region of South America where it was used to improve soil. Much of the soils of the Amazon Region are acidic and have poor nutrient retention properties due to high rainfalls which wash the nutrients away. These two factors made sustainable agriculture very difficult. Over time, the early farmers learned to survive by establishing small communities made possible by small-scale land clearing, using fire. Domestic waste and pottery shards (clay materials high in iron) were added to these burning piles that were later covered with soil, allowing them to smoulder and extinguish. Over time the treated soil took on a black colour and today is referred to as Terra Preta, or black earth. These early farmers discovered that treated areas produced greater crop yields and that unproductive land was turned to sustainable agriculture, resulting in an increase in the number of communities across the region. Biochar, as we call this black material today, is a modern word to describe forest and agricultural waste materials that are pyrolysised (using heat to decompose organic material in a low-oxygen environment) and used as a soil amendment. Biochar generally is alkaline. It has been discovered that using biochar on acidic soils can raise the soil ph (a numeric scale used to specify levels of acidity) to improve agricultural productivity. It opens up land which was once considered too acidic for agricultural production. FDI: What benefits do you achieve by using biochar and what effect does it have on soil? KF-W: There are many possible benefits to biochar, including the following: The ability to hold twice its weight in moisture. Biochar has a high cation exchange capacity. This enables a wide range of nutrients to be bound together which are then added to the soil as a form of fertilizer or conditioner. A further benefit of this process is that it reduces nutrient leaching and pollution of the water table. Correctly used, biochar can also reduce plant stress, such as that caused by the impact of salinity during periods of drought by providing a reservoir for plants to access moisture. It also provides a habitat that supports fungi and bacteria. Biochar is also able to aerate heavily compacted clay and, in so doing, reduces the overall density of soil by allowing moisture to move, roots to develop and nutrients to flow to plants. Page 3 of 6

4 Biochar also is able to cause porous sandy soils to retain moisture, thus reducing the need to irrigate and thus help to provide a habitat for soil life. Biochar is also able to bind pesticides and chemical spills. Biochar can spread through various layers of soil, thus extending from its original place of deposit and, in so doing, opening compacted layers of soil. As a result, the activity of earth worms and dung beetles can be enhanced. Biochar has been used in cattle feed lots and chicken pens. It is also easy to transport in bulk because of its light weight due to its porosity. To accelerate the pyrolysis process, a primary requirement for making charcoal for agricultural or for domestic or commercial factory use, is that the raw material must contain as little moisture as possible. If suitably dry material is sourced, biochar can be produced in a simple dug out pit. For larger, commercial quantities in the developed world, charcoal, or its end use being biochar, is generally produced in kiln or retort type structure at temperatures ranging from 400 o C to 750 o C. Biochar can be produced from a wide range of raw materials. In developing countries, where charcoal is frequently a source of heating and cooking, this can be inexpensive. In semi-nomadic and village cultures in Africa, simple materials such as dead wood and cattle dung are used while in Asia common materials include bamboo, contaminated rice straw and animal dung. In developed nations sources include trees grown for biochar production, tree waste from furniture factories, contaminated grain, straw and the list goes on. Even dead animals and chicken manure can be converted into charcoal. Not all charcoal can be converted into biochar for agricultural use, however. For example, human sewage sludge often contains heavy metals and other contaminants that have entered the sewage system and would be harmful to soil if applied. Treated wood is also another example of a material that is not suitable for making into biochar for use in agriculture. There is now considerable research being undertaken around the world into the use of charcoal to sequester CO 2 into the soil through the application in agriculture of charcoal in the form of biochar. During the process of making charcoal, a by-product is produced known as Pyro ligneous Acid. It is also known as wood vinegar (WV). WV is the condensate that comes from the smoke when the biomass is being carbonised. WV has been used in Japan and in many Asian countries for centuries. It has a wide range of uses and there is significant research being conducted into its application. China is one of the world s leading nations researching the applications for WV in agriculture and in other fields. The WV contains water, acetic acid, methanol, acetone, oils and heavy tars from the process of distillation of the smoke that rises during the second and third stages of the pyrolysis procedure. The residues form into three layers, where the heavy tars settle to the bottom, the pyro ligneous acids (WV) settle in the middle and the light bio oils settle on the surface. Generally, this settling period goes on from three to 12 months for particle settlement. Uses of WV are: Page 4 of 6

5 Bio-oil is a crude oil, which is sold to bio fuel refineries and can be converted into transport fuels like diesel. Pyro ligneous acid can be used in a wide range of agriculture applications. Applications of WV have helped in seed germination rates in broad acre agriculture. It has been used as a spray for leaves, resulting in greater photosynthesis. As a soil application it has been used to promote healthy soil biota with increased beneficial fungal and microbial activity. It is used in animal feedstock applications to increase chicken health, meat and egg production. Adding wood vinegar to composts aids in the increase of beneficial microbial activity, which speeds up the process of composting. The Tar has applications in agriculture as an additive for sealing wounds after castration and as an ingredient used in sealing horse hooves. Industrial applications include using the tar as part of a road base or as a preservation oil used for timber. FDI: How do you apply biochar to your soils and how do you determine your rates of application for an area to be treated? KF-W: At present, our technique of applying the biochar is relatively low on technology but high in labour. The process of activating our biochar, with WV imitates as much as possible what occurs in nature. WV is an integral part of bushfood farms growth success at Brookton. On our property, the effects of Dryland Salinity have been our primary concern, particularly once we understood the extent of the problem and the possible long term outcomes if we did not manage the land with considerable care. Dryland Salinity is not the result of a single cause; the remediation of the land was going to require a multi-layered approach to understand how to mitigate its effects and has dictated our farming strategy, especially in regard to what would successfully grow in the long term. During our initial phases we consulted with professionals from the University of Western Australia. This enabled us to determine what we could grow, how we could grow it and, at the same time, help in the mitigation of the rising water table and dissolved salts. The initial strategy required the planting of a range of very salt tolerant trees and shrubs known as Halophytes along and around the zones which had an open salt scald. These would act as pumps to naturally begin the process of lowering the water table and, in due course, take with it the surface salts. In addition, salt tolerant coloniser plants and weeds could come in and help to expedite revegetation. The discovery of biochar and WV occurred by accident as a result of observing the burning off of bushland and the smoke that was produced. After we had gone through the burn off, we stopped a few weeks later to rest before continuing our journey and noticed the fresh carbonised material on the ground and how quickly life had returned. The emphasis here was on how quickly green life had returned - this was our Eureka charcoal/biochar moment. Research quickly ensued, resulting from our limited knowledge in the use of pyro ligneous acid in agriculture. We looked into how to produce biochar for us on our property. We based our application rate, from information sourced on the internet, to be one tonne per acre (0.4 tonne/hectare). The amount we were looking at was about four tonnes initially. Because of the urgency and the lack of knowledge on producing biochar, we turned to a company called Simcoa Pty Ltd, located in the southwest of WA. Page 5 of 6

6 I will continue this story in the next edition of this interview. ***** About the Interviewee: Treōwstede is a retirement strategy for Barry and Karry. Both agreed it was important to have a lifestyle that kept both physically fit, lowered the health their risk associated with illness associated with ageing. Buying a small rural property within close proximity to Perth would enable them to manage their retirement years enjoy a simple semi-rural lifestyle, importantly, providing an opportunity to supplement their income. In addition, the legacy they will leave will be long lasting. After 2½ years of textbook, internet searches, joining groups and developing networks of like-minded people in the Natural Farming Community and users and producers of biochar, they are well on their way with their Bushfood Farm and Apiary Project. As Karry puts it, there are so many opportunities to value add with their naturally farmed produce, with a focus on single source where ever possible, the opportunities are only limited by ones imagination. The key to the project is simple, limit your lines, be unique, and keep it boutique! Both Karry and Barry continuously enjoy learning about the benefits Natural Farming on the environment and the ability to repurpose waste materials for use as farming amendments. ***** Any opinions or views expressed in this paper are those of the individual interviewee, unless stated to be those of Future Directions International. Published by Future Directions International Pty Ltd. 80 Birdwood Parade, Dalkeith WA 6009, Australia. Tel: Fax: info@futuredirections.org.au Web: Page 6 of 6