Effect of Applying Hong Kong Biosolids and Lime on Nutrient Availability and Plant Growth in an Acidic Loamy Soil

Abstract

A greenhouse experiment was conducted to evaluate the growth of Brassica chinensis L. in an acidic loamy soil amended with municipal biosolids with or without lime treatment (750 mg kg(-1)). The soil was amended with one of two municipal biosolids from Tai Po (TP) or Yuen Long (YL) wastewater treatment plants at application rates of 0, 5, 10, 25 and 50% (v/v). Initial NH(+)4-N and PO(3-)4-P concentrations in the amended soil increased with an increase in municipal biosolids loading rates and those with biosolids from TP had a greater increase in nutrients than those from YL. However, initial NO(-)3-N contents in both municipal biosolids amended soils decreased with an increase in biosolids loading rates, particularly for the soil amended with YL. Soluble K, Mg, Na and Ca concentrations in the soil increased with application rates. Municipal biosolids amended soil without lime treatment had higher NH(+)4-N, NO(-)3-N and major cation contents than those with lime. Addition of Tai Po municipal biosolids and lime significantly increased the dry weight yields of B. chinensis L., while YL municipal biosolids increased yields only at the 5% rate with lime amendment. The maximum growth was obtained at municipal biosolids application rates of 5 and 10% for TP and 5% for YL for limed soil. Addition of municipal biosolids increased the total N, P, Zn, Cr and major cation concentrations in the shoot tissue, while lime treatment reduced Zn and Cr contents. The high salt and metal concentrations would likely be factors inhibiting plant growth at high application rates, especially for YL biosolids. Further studies to determine the long-term effects of biosolid application on soil and crop quality are warranted.

Biomass production, metal and nutrient content in sorghum plants grown on soils amended with sewage sludge

“…The total concentration of P, Ca, Mg, K, and Zn in the PS was similar to those published by Warman and Termeer (2005) and Bozkurt and Yarılgaç (2010). Mendoza et al (2006) presented similar concentration values to those obtained in this study for Pb and Ni, while concentrations of Cr and Cd in our study were lower than those reported by Wong et al (2001) and Bozkurt and Yarılgaç (2010) (Table 2). The concentration of Cu, Zn, Pb, and Cr present in both sludges is below the maximum concentration allowed for agricultural soils according to international regulations (United States, Brazil, Switzerland, Sweden, Scotland, Belgium, Denmark, Germany, France, Italy, Holland, and Spain) (de Melo et al, 2015).…”

“…The chemical characteristics of the used sludge are presented in Table 2. The PS presented an alkaline pH similar to Wong et al (2001) for a sludge collected from a Hong Kong WWTP and another one generated in India reported by Singh and Agrawal (2008). The concentration of total C (290 g C kg À1 ) of the PS was similar to the concentrations reported by Wong et al (2001) and by Mendoza et al (2006).…”

“…The PS presented an alkaline pH similar to Wong et al (2001) for a sludge collected from a Hong Kong WWTP and another one generated in India reported by Singh and Agrawal (2008). The concentration of total C (290 g C kg À1 ) of the PS was similar to the concentrations reported by Wong et al (2001) and by Mendoza et al (2006). The total N content was similar to Singh and Agrawal (2008) and Warman and Termeer (2005), 34 and 32 g N kg À1 , respectively.…”

“…The total N content was similar to Singh and Agrawal (2008) and Warman and Termeer (2005), 34 and 32 g N kg À1 , respectively. However, Wong et al (2001) and Bozkurt and Yarılgaç (2010) published higher (65 g N kg À1 ) and lower N values (24.8 g N kg À1 ), respectively (Table 2). The total concentration of P, Ca, Mg, K, and Zn in the PS was similar to those published by Warman and Termeer (2005) and Bozkurt and Yarılgaç (2010).…”

Cadmium uptake potential of Brassica napus cocropped with Brassica parachinensis and Zea mays

“…Pots, three replicates each for a treatment, were placed on greenhouse bench top in a randomized block design with a temperature range of 25-35 • C. The water content of the soil was maintained at an average of 60% WHC by watering to weigh daily with deionised water. Nutrients were provided to plants after 14 and 28 days of planting as described by Wong et al [20].…”