HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Mahdy, A. M. Articles by Lin, Z.-Q. Search for Related Content PubMed PubMed Citation Articles by Mahdy, A. M. Articles by Lin, Z.-Q. Agricola Articles by Mahdy, A. M. Articles by Lin, Z.-Q. Related Collections Phosphorus Plant and Environment Interactions Soil Pollution Other Soil Management Municipal Waste

TECHNICAL REPORTS

Waste Management

Effects of Co-Application of Biosolids and Water Treatment Residuals on Corn Growth and Bioavailable Phosphorus and Aluminum in Alkaline Soils in Egypt

^a Dep. of Soil and Water, College of Agriculture, Alexandria Univ., Alexandria, Egypt
^b Salinity and Alkalinity Soils Research Lab., Ministry of Agriculture, Cairo, Egypt
^c Dep. of Biological Sciences & Environmental Sciences Program, Southern Illinois Univ.-Edwardsville, Edwardsville, IL 62026-1099

^* Corresponding author (zhlin{at}siue.edu).

Received for publication July 22, 2008. The co-application of biosolids and water treatment residuals (WTRs) has been previously trialed to reduce excessive bioavailable P in the soil treated with biosolids. However, uncertainty still exists regarding the environmental consequences of the co-application of biosolids and WTRs, especially in alkaline soils in Egypt or the Middle East region. A greenhouse pot study was conducted with Egyptian alkaline soils to (i) quantify the effects of co-application of biosolids and drinking WTRs on biomass production of corn (Zea mays L. cultivar single hybrid 10), (ii) determine the co-application effects on Olsen-P and KCl-extractable Al in relation to their accumulation in plant tissues, and (iii) optimize the co-application ratio of biosolids to WTRs for the best yield and effective reduction of soil bioavailable P. The results show that, among the studied soils treated with 1% biosolids along with various rates of WTRs, the corn yield increased significantly (P < 0.01) with increasing WTR application rate from 0 to 3% (w/w), but decreased at 4% application rate. The corn yield also significantly correlated with soil water holding capacity that increased with the addition of WTRs. Phosphorus uptake by plants significantly (P < 0.01) increased when the biosolid application rate was increased from 1 to 3% in the three studied soils that were treated with 1, 2, or 3% WTRs. The application of 4% WTRs in the biosolid-amended soils resulted in a significant reduction in soil Olsen-P values, but without having observable phytotoxicity of metals (such as Al) to corn during the growth period. The effective co-application ratio of biosolids to WTRs, for increasing corn yield and minimizing the potential for bioavailable P in runoff, was approximately 1:1 at the application rate of 3% biosolids and 4% WTRs in the alkaline soils.

Abbreviations: DW, dry weight • OM, organic matter • WHC, water holding capacity • WTRs, water treatment residuals