A friend of ours, Randy Bevis, introduced us to the idea of running a barrelponics system at ISDSI.  Randy runs a development project north of Chiang Mai city where they raise fish for stocking aquaculture ponds in local communities.  We looked into the system, and found a great resource online at F.A.S.T with the barrelponics manual and more information on aquaponics in general. This January on of the ISDSI students from Kalamazoo College, Adam Smith, decided to take on the project, and as part of his J-Term independent study built a barrelponics system at ISDSI, where it is now running with fish (tilapia) and growing vegetables. It is a great small scale system, and we are going to run it and monitor the system to see how we can adapt it to urban sustainability projects — as well as provide fish and vegetables for ISDSI.

The basic idea is to link fish with hydroponic vegetable production, where the fish waste provides nutrients to the plants, and the plants in turn clean the water for the fish.  The only input needs to be fish feed, since energy is taken out of the system in the form of plants and fish.

Here are some photos of the build and an explanation of the system.

The system before loading in the gravel for the hydroponic beds.

Adam linking together the grow beds and the fish barrel. The gravel deformed the barrels, so we added a strap to keep them from deforming too much.

Water from the fish barrel is pumped up to a float tank, and then as it fills a recycled water bottle, it opens a valve (the same as in a toilet) and water flows into the system. This shows the gravel beds and the fish tank.

The first test of the water flowing into the gravel beds -- the water flows in, and then drains into the fish tank before cycling back up through the system.

The whole system -- you can see the tank that holds the water, the water bottle that fills and empties to trigger the valve opening, and the pipes into the grow beds. You can also see the vegetables starting to grow in the gravel beds.

Before the vegetables were big enough to clean the water, Adam found the ammonia levels going up, so we went to the Ping River and pulled out some water hyacynth to help filter the water. (Lydia was more than willing to get her hands dirty and wet...)

The float tank with water hyacynth and water lettuce helping filter the water. We can pull these out as the vegetables get bigger.

Adam explaining the system to students at ISDSI.

Congratulations to Adam on a job well done!

The first Expedition Field Course of the fall semester is our course on Agroecology.  More than just a course about organic and agroecological farming, the course spends a lot of time exploring food systems, agricultural systems, and the relationships between farmers, fields and consumers.

A core part of the course is learning about different plants and how they fit together as an agroecological system.  This is foundational to understanding how this type of farming can be more sustainable than monocropping, with emerging research showing organics tend to be healthier (due to their natural defenses kicking in), higher yields in some cases (in terms of biomass as well as food), as well as some interesting research hinting at higher rates of carbon sequestration for organic and agroecological farming over “conventional” farms (“conventional” meaning high chemical inputs on monocrops, not “conventional” as in what humanity has done for most of history).

Each year the course adapts to current needs and work being done by our village partners and the folks at the Upland Holistic Development Project. What remains year-to-year is a great  opportunity for students to learn about plants and how they fit together in creating a healthy agroecology.  Here is what it looks like:

First, using field guides student go into the fields and forests to identify plants used in agroecosystems.

Next, plants are identified and marked down in relation to other plants and physical features of the landscape.

Healthy agroecosystems (in this case an agroforest) tend to have a LOT of plant diversity.

FInally, working off of maps and field notes, the plants are identified and systems are mapped.

Great new movie out in the theaters in the US.  I’ve not seen it yet, but am working on getting a copy and hopefully we can get a screening here in Chiang Mai.  The folks involved have a deep understanding of food systems, and for anyone interested in sustainability this is really required viewing.

Several of the people in the trailer are authors we read on our courses, and this is a great fit with our course on agroecology as well as several of the other courses that link into food systems issues, such as our forests course.

Featuring interviews with such experts as Eric Schlosser (Fast Food Nation), Michael Pollan (The Omnivore’s Dilemma, In Defense of Food: An Eater’s Manifesto) along with forward thinking social entrepreneurs like Stonyfield’s Gary Hirshberg and Polyface Farms’ Joel Salatin, Food, Inc. reveals surprising—and often shocking truths—about what we eat, how it’s produced, who we have become as a nation and where we are going from here.

Go to the website here for the trailer and other information: http://www.foodincmovie.com/

Any movie with a bar-coded cow has to be good.

If you see it, let us know what you think in the comments!

Here is some of the news about ISDSI in 2007:

• One of our favorite companies making a difference for sustainability is Patagonia. Our program was highlighted in Patagonia’s blog, The Cleanest Line. Read the full entry here. (June)

• ISDSI helped organize the first Southeast Asia ECHO Agricultural Conference. We were involved in the planning committee, helping to increase participation from Thai development workers, and ran a workshop, Global Climate Change: Implications for agriculture and community development. (June)

• An article explaining the ISDSI approach to cross-cultural place-based education is online “A New Model for Study-Abroad” (a pdf version is available here). This was published in The Bangkok Post on March 20, 2007 and can be read online. (March)