Study On The Remediation Techniques Of Degraded Saline-alkaline Wetlands Using Paner Mill Wastes In The Yellow River Delta

Extensive wetlands in the Yellow River Delta have been degraded into saline-alkaline wetlands, resulting in the waste of abundant of land resources. Thus, it is vital to regain ecological security by remedying the degraded saline-alkaline wetlands. The key to the remediation is the decrease of soil salinity. Paper mill wastes, such as paper mill effluent, paper mill sludge and wheat straw residue were used in this study as remediation materials; different techiques were taken according to the characteristics of the wetlands with different degradation levels. Slightly and moderately degraded saline-alkaline wetlands were remedied by irrigation with different frequency of treated paper mill effluent by decreasing soil salts and increasing soil nutrients, microbial population and activity. Two different techiques were utilized for the remediation of severely degraded saline-alkaline wetlands, including1)irrigation with different amount of treated paper mill effluent in combination with plowing and building anti-water-logging ditches, and2)Treat paper mill effluent, paper mill sludge and wheat straw residue were utilized in combination with plowing and buiding anti-water-logging ditches. Improvements of plant growth and soil properties were used to reflect remediation effects, and the results demonstrated that all the techniques presented certain remediation effects. In addition, the opitum parameters of each remediation techniques were exoplored in order to supply theoretical support and technical guidance to the remedation of the extensive degraded saline-alkaline wetlands in the Yellow River Delta.