The fly ash possesses definite water-adsorption capacity, and it also contains various nutrient elements so that it may improve quality of soil obviously.
粉煤灰具有一定的吸水能力，其本身含有多种养分元素，可以明显改良土壤理化性质。
2
Marsh plant has very important function in constructed wetlands system. It has not only adsorption and application nutrient in sewage, adsorption and enrichment heavy metal of sewage.