The capacity of water hyacinth as biofilter and bioaccumulator based on its size

Nowadays, aquatic environmental contamination caused by human activities is increasing. One of several types of contaminants is heavy metal. Water hyacinth, Eichhornia crassipes (Mart.) Solms. is an aquatic plant that has been known to have a capacity to absorb heavy metals through its roots. Previous study reported that water hyacinth can reduce the amount of the suspended solid in the water. The objective of this study is to evaluate the performance of three sizes of water hyacinth in filtering the suspended solid from turbid water. The experiment was conducted in a greenhouse over a period of seven days on August 2019. The plant material was obtained from water body in Sawangan, Depok area. We used fifteen plants which categorized into three sizes of water hyacinth, i.e. small, medium and large. Those plants were first acclimatized for a period of seven days in tap water without addition of nutrients. For the next seven days, the water hyacinths were transferred to a fiberglass rectangular fish tank filled with 50 L water from Situ (Lake) Agathis, Depok. From the results, it was found that the accumulation capacity of lead (Pb), cadmium (Cd) and copper (Cu) by water hyacinth decreased by the increase of plant size. Another result showed that compared to leaves and stems, roots accumulate more heavy metals. Under seven days of growing period, all the fifteen water hyacinth plants can reduce the total dissolved solids (TDS) from 261 ppm to 204 ppm, and total suspended solids (TSS) from 0.0449 ppm to 0.0151 ppm.