Reedbeds and Sewage

The Eco cabins at CAT have their own reed bed systems which are used to treat sewage. Reed bed  sewage systems use a series of natural filtration systems to treat waste water. Discharging of raw wastewater has a negative impact on the environment such as eutrophication of receiving water bodies, pollution of groundwater and odor. What is more, wastewater contains pathogenic organisms which transmit disease to animals and human. For these reasons it is crucial to have an effective sewage management system and operate it in proper way. This is what our biology department does.


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A comparison of two methods of mushrooms cultivation

Today I would like to talk more specifically about how we cultivate our mushrooms here at CAT. Currently, we are testing out 2 different methods so as to compare the results. One method uses straw or cardboard while the other method uses sawdust. In both cases, the straw/cardboard or sawdust must be pasteurised in order to clear them from micro-organisms so that the mushrooms can proliferate easily. This is done by putting them in boiling water for about 2 hours.

In the first method, the straw/cardboard is put in layers in a box with a small mycelium culture (i.e. spore culture), closed in a plastic bag and left in a hot room for about 2 weeks until it is completely colonised by mycelium. The straw is then put into a fruiting room, which is much colder. The cold shock that the mycelia undergo at this stage, make them start fruiting, i.e. growing into mushrooms. This process should take about 2 weeks as well.


The second method uses sawdust, is easier but takes longer. In this case, the mycelium culture is put into the sawdust and in an incubator until the mycelium culture colonises the whole container. The saw dust is then taken out and packed into pre-drilled holes in logs that have been kept on the ground for 2 years (this is to replicate the natural decomposition process). The logs are then left for about 6 month and should, hopefully, grow oyster mushrooms.


Mushrooms propagation or how to grow valuable protein resources

My name is Ariana, I am a long term volunteer in the biology department and today I would like to tell you more about our recent forays in the realm of fungi, that special kingdom not quite plant not quite animal.

Mushrooms are divided into different categories according to the substrate they live on; saprophytic mushrooms that break down organic matter and replenish the soils, parasitic mushrooms that colonize living organisms and mycorrhizal mushrooms that form symbiotic associations with plant roots.

Aside from performing important functions in nature like decomposing and recycling nutrients, mushrooms have a wide range of applications very useful for humanity. In Europe they are most famous for their culinary use, whereas in the East they are most widely employed in medicinal use; in Japan most cancer treating drugs are derived from mushrooms, and in China a huge variety are sold dry as health tonics.

Mushrooms have also been successfully used as barriers for excess nutrient in a process known as mycofiltration, as cleaning agents for toxic pollutant contamination (mycoremediation), and as inhibitors of undesired plant growth (mycopesticides). Mushroom propagation is a low impact very accessible technology that can be adapted to a range of climates, skills, time and materials available.

To propagate mushrooms here at CAT we use, an incubator to keep a stable warm temperature so that the original culture becomes established, an autoclave for sterilization of cheap grains (which the culture can use as a food source to get stronger), and a variety of woody wastes from CAT as substrate for mushroom fruiting.

Hardwood logs plugged with mushroom spawn have been part of the displays of the biology department as an example of ways to grow valuable protein sources on a shady corner of a garden or a forest. This year however, we are conducting experiments to increase the viability of the crop, and hopefully establish a production system that might allow us to do some more research on other exciting applications of fungi. To start with we are collecting different waste products from the many activities that go on at CAT (glass bottles and coffe grounds from the restaurant, bits of straws and hemp from the graduate school, woodchip and sawdust from the building department, cardboards…) and testing them for their suitability as substrate for oyster mushroom production, a species that will be a welcome addition to the restaurant kitchen.

Stay tuned for fruiting developments!


Vole family in our gardens

Morning Everyone, Keeping Roger our gardener and his volunteers company in the garden is a family of voles which seem to have set up home under one of the tarpaulin sheets. They are probably Field Voles, although Bank Voles are very similar and to add to the confusion Field voles sometimes frequent hedgerows and Bank voles can be found in scrubland as well! The Field vole is slightly larger and less reddish and has a shorter tale but as a fleeting glimpse is usually all you get it is difficult to identify with any certainty.

Most of us have seen voles but sometimes you are not quite sure what you’ve see – if you spot something that looks a bit like a small sausage with tiny legs suddenly shoot across the path or lane in front of you it is probably a vole. They are in fact one of our commonest small mammals with a phenomonel breeding rate–a single female can have up to 6 or 7 litters a year and the young become sexually mature at a few weeks old. Mind you they have to reproduce so prolifically as the poor old vole is preyed on relentlessly and is the main food source for many predators–it is the staple diet of Barn Owls (some owl pellets I’m dissecting at the moment contain practically nothing else but vole bones) and foxes like nothing better than a couple of tasty vole snacks as an appetiser before their main course.

In fact it is likely that very few voles live their full lifespan–most of these inoffensive and rather cute little creatures end up as a food item for some hungry predator. The other species of vole found in this country is the much larger Water Vole (the Ratty of Wind in the Willows) which lives as the name suggests in and around inland rivers. You have to work quite hard to observe most of our native mammals but it is worth the effort – so make the most of any chance encounters you have.


From Bristol to CAT: Countryfile takes on Sustrans

On the 4th of May, the Countryfile Magazine editorial team and Rich from Sustrans are racing from Bristol to the Centre for Alternative Technolgy in Machynlleth, mid Wales using a variety of different travel methods. They aim to explore the trials and the triumphs of travelling in rural areas. Each person will take different routes and judge how efficient it is a way to travel based on time, cost, experience, environmental impact and the effort (calories/ energy/ stress)


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Plants are endlessly fascinating. In May I’m going to spend three days looking at how they grow, on our Botany for Gardening course

by Chloe Ward
When i was a kid i made a little promise to myself that i would never, ever be as boring as my Mum and Granny who would walk up and down their rows of vegetables discussing each one. It’s a promise I’m happy to break though. Plants are endlessly fascinating. In May I’m going to spend three days looking at how they grow, on our ‘Botany for Gardening’ course. We’ll be doing little experiments and stuff that was boring at school, but strangley is really fun now. There’s still spaces if you want to join in.

Thoughts on peat in response to questions and comments from twitter and facebook. I’d back a levy, but I’d prefer a ban

by Chloe Ward

I would back a levy, though of course i’d prefer a ban. It would be hard to sell bags of peat under the table in the pub, thought i guess it would happen. (trucks in the night?)

It astounds me on how slow the horticulture industry is to stop using peat. I’ve been a gardener for twenty years. I have never, ever used peat or felt the need to. At CAT we make up our own seed and potting mixes, but in other gardens i’ve used commercially sold organic mixes which also work fine. If you’re choosing a potting compost, they do vary in quality, so shop around until you find one which suits you. In 2010 ‘Which? Gardening’ awarded ‘Best Buys’ to three peat free potting composts – Vital Earth Tub and Basket Compost, New Horizon Mulit-Purpose Compost, and Vital Earth Multi-Purpose Compost.

Another big irritation on the peat-front is how sneaky the sellers are in their labelling. For example, recently i have seen a grow-bag labelled as “20% peat-free”. What does that mean, if not 80% peat? So, watch out for that – if in doubt, look for organic certification.

MSc Environmental Change and Practice

Environmental change will affect many aspects of society including the working practices and research agendas of the built environment professions.

Students in the sun at the Centre for Alternative Technology

Responding to this change, a new and innovative master’s degree is commencing at CAT in September 2011 in collaboration with the Cardiff School of Art and Design, University of Wales Institute Cardiff (UWIC).

The aim of the programme is to provide students with the theoretical knowledge and the research and practical skills to be able to operate effectively within their chosen field of the Built Environment, while responding to environmental change. The focus is on buildings and the built environment and is intended for architects, builders, planners, engineers, surveyors, researchers, academics and other built environment professionals and experienced individuals. Students may link coursework to their professional work projects, volunteering projects and/or current research projects running at CAT and at UWIC.

Heliodon pair

A portfolio of work is produced including practical work, case studies and reports. Intensive one week modules are held at CAT and at UWIC, and the programme is available Full Time (1 year) or Part Time (2 years).

Find out more.

Illegal vegetables and how to grow them

by Chloe Ward

Wheel barrow in the gardens at CAT

Do you like the sound of this bean? Want to grow it too? I could sell you some seed for a quid. Bargain? Sadly, though, the law does not permit it. It is illegal to sell my bean seed. Why? Do the seeds yield an illegal drug? Is it an invasive species likely to wreak havoc on our natural ecosystems? Does the plant contain some kind of hazardous toxin? No – it’s just a sweet, innocent, harmless bean, a Climbing French bean with the botanical name of Phaseolus vulgaris. But French beans come with cultivar names too, like ‘Neckar Queen’ and ‘Blauhilde’ and mine hasn’t got one. It’s got no birth certificate. This is the problem. Ever since the passing of the Seed (National List of Varieties) Act 1973, a vegetable seed can only be sold if it is on a special list. To get on the list it has to pass a DUS test. It must be Distinct (different from all other varieties), Uniform (all the plants grown from a pack of seed must be the same) and it must be Stable (the plants should not change from generation to generation). The vegetable seeds for sale today are all on the list. The ones your neighbour gives you may not be.

You can read the rest of this article here

This article was first published in CAT’s Clean Slate magazine.

Growing up: A new age for forest gardening?

by Chloe Ward
Forest gardening offers an environmentally sound way of growing without the back-breaking work. But has it has it lived up to expectations?

Working on the forest garden
I remember clearly the moment of my conversion. 1991 saw the publication of Forest Gardening – the launch of a new way of growing food. It was the most environmentally sound system you could imagine. A vision of food production that was not just low impact but actively beneficial. The idea was enthralling to an aspiring ecological grower. It gave a new direction for the future. I was instantly seduced. Robert A de J Hart (1913-2000) was inspired by the home gardens of the tropics such as those in Kerala, India, in which a wide variety of food plants grow in a small space, above, below and around each other in an organised tangle, similar to the natural forest that grows nearby. It made perfect sense. Why grow crops in one thin layer spread over the earth’s surface when nature makes use of vertical space right up to the tree canopy? Robert set about developing a system of three dimensional food gardening for the temperate environment. He designed a garden comprising a mixture of edible plants: trees and shrubs with bushes below and a ground layer of perennial or self-seeding plants below these. Read the rest of this article here This article was first published in CAT’s Clean Slate magazine.