By Zac Sarian
A retired lady professor from University of the Philippines Los Baños (UPLB) who is an environmentalist has developed a practical technique of rehabilitating polluted streams and shallow rivers so that they can become sustainable fish habitats that will be sources of food for communities.
The lady is Dr. Macrina T. Zafaralla, emeritus professor of the Institute of Biological Sciences at UP Los Baños. Her technique comes by the forbidding name of Aquatic Macrophyte Biosorption System (AMBS). However, it is very simple in layman’s terms.
The AMBS simply involves putting a barrier consisting of bamboo poles across the stream to keep in place the “macrophytes” which are actually either kangkong or water hyacinth. The water plants serve as a filter to the floating solid pollutants while the roots develop into a mat that adsorbs and absorbs the molecules of pollutants that are dissolved in water. This system keeps the water clean and conducive to the proliferation of aquatic life.
Throughout the length of the stream or shallow river, the bamboo barrier and water plants could be installed about one hundred meters apart. Each of these installations becomes a place where the fishes and other aquatic creatures (shrimps, snails, etc.) grow and multiply.
The technique is an original concept as far as Dr. Zafaralla knows. She has not seen a similar idea like it in the Philippines or elsewhere. How did the lady professor conceive of the idea? It all started about seven years ago when she saw a young girl frolicking in the polluted water of Molawin Creek right on the campus of UPLB. She was splashing the dirty water over face and possibly drinking some of it.
Dr. Zafaralla said to herself that the little girl must be saved from the danger of imbibing the dirty water. Then she thought of the water hyacinth (called water lily by most Filipinos) and kangkong as possible cleanser of the dirty stream water. She immediately put her idea into action. With the help of student volunteers, they cleaned up Molawin Creek and installed her AMBS. After a while, voila! The idea worked wonders. The water became clear and in no time at all, tilapia, dalag, shrimp, hito, shells were proliferating and the place became a veritable source of food.
Dissemination of the AMBS soon became the advocacy of the Institute of Biological Sciences but because most of the IBS faculties were busy with their work, Dr. Zafaralla has virtually become a one-woman army doing the rounds spreading the good news about her technology. Aside from Molawin Creek, her technology has been adopted in the Panglao River in Lipa City, the Silang-Sta. Rosa River in Laguna and Cavite, streams in Tanay, Rizal, and elsewhere. In fact, as we were writing this piece, we learned that Sec. Gina Lopez of the Department of Environment and Natural Resources had recruited her to go to Negros with the mission of spreading her technology.
Dr. Zafaralla stresses that to make the rehabilitated streams and rivers remain clean and productive on a sustained basis, members of the community should protect the integrity of the water system. They should not allow overcrowding of the water plants. And they should not dump their garbage there.