Constructed wetlands are known widely by their characteristic properties like utilization of natural processes, simple and easy of construction, operation and maintain as well. The constructed subsurface flow wetland is designed as a tank with an impervious boundary to prevent seepage and contain a suitable porous media in which emergent plants grow. The water remains below the surface of the gravel/stone/rock media. Soil in constructed subsurface flow wetland absorbs and stores organic matter several years. This accumulation potentially leads to a decline of the filter ability of the constructed wetland. | The 5th International Symposium on Southeast Asian Water Environment 7 - 9 November, 2007. Chiang Mai, Thailand ================================================================================ ORGANIC MATTER DISTRIBUTION OF THE ROOT ZONE IN A CONSTRUCTED SUBSURFACE FLOW WETLAND Le Anh Tuan1,2) and Guido Wyseure2) 1) Department of Environmental and Water Resources Engineering, College of Technology Can Tho University, Campus II, Street 3/2, Can Tho City, Vietnam E-mail: latuan@ 2) Division for Land and Water Management, Faculty of Bioscience Engineering Katholieke Universiteit Leuven, B-3001 Heverlee, Belgium E-mail: Abstract Constructed wetlands are known widely by their characteristic properties like utilization of natural processes, simple and easy of construction, operation and maintain as well. The constructed subsurface flow wetland is designed as a tank with an impervious boundary to prevent seepage and contain a suitable porous media in which emergent plants grow. The water remains below the surface of the gravel/stone/rock media. Soil in constructed subsurface flow wetland absorbs and stores organic matter several years. This accumulation potentially leads to a decline of the filter ability of the constructed wetland. A survey on the vertical and horizontal distribution of the organic matter in sand bed was done in the experimental constructed subsurface flow wetland in Can Tho University’s campus, Vietnam. The linear decreasing organic matter distribution to the increasing vertical and horizontal flow direction is confirmed as the hypothesis in highly deposition of suspended solids and organic matters in the head section of the root zone. It also proves a homogeneous flow pattern in the system Keywords: Constructed wetland, wastewater, organic matter, distribution, root zone. 1. Introduction Constructed wetlands (CW) are mainly built for wastewater treatment purposes. CW are widely used in the USA, Europe and some .
