Sustainable agriculture has become a hot topic of late.

As global population increases, countries around the world are investing in new ways of perpetual growing and self-sustaining agriculture. Led by teacher Claire Mitchell, the AP Environmental Science class at HBA has begun the process of caring for eco-columns, which are small-scale models of self-sustainability. These are housed in Mitchell’s classroom under lights that mimic solar activity. What is an eco-column, exactly? “Ecocolumns are mini, self-contained systems designed to mimic natural ecosystems. They are comprised of terrestrial, decomposition, and aquatic chambers,” explained Mitchell.

For the construction of the eco-columns, students could choose to use a conventional, three-layer design, featuring an aquatic layer on the bottom, a detritus/compost layer in the middle, and a plant/terrestrial layer on the top. The layers are all connected and allow water to flow through consecutively. Nutrients such as nitrogen and phosphorous from the plant layer are flushed down to the detritus layer, where the earthworms further enrich the water to allow the fish in the aquatic environment below to sustain themselves on the nutrient-rich liquid.

Students who chose to deviate from the conventional design used whatever structure they thought best suited their life forms. For example, one group of students reversed the detritus and terrestrial layers and added a sand layer between the aquatic environment and the terrestrial one. The sand acts as a natural filter so that the water in the aquatic environment won’t become overly rich in nutrients or contain any large particles.

Students were also allowed to use coffee filter paper and cotton balls to filter particulates from the water before it enters the aquatic environment. “It’s fun, not that difficult, and provides insight to us students,” said senior Joshua Arenas.