The effects of different sewage sludge amendment rates on the heavy metal bioaccumulation, growth and biomass of cucumbers (Cucumis sativus L.)

Abstract

When sewage sludge is incorrectly applied, it may adversely impact agro-system productivity. Thus, this study addresses the reaction of Cucumis sativus L. (cucumber) to different amendment rates (0, 10, 20, 30, 40 and 50 g kg) of sewage sludge in a greenhouse pot experiment, in which the plant growth, heavy metal uptake and biomass were evaluated. A randomized complete block design with six treatments and six replications was used as the experimental design. The soil electrical conductivity, organic matter and Cr, Fe, Zn and Ni concentrations increased, but the soil pH decreased in response to the sewage sludge applications. As approved by the Council of European Communities, all of the heavy metal concentrations in the sewage sludge were less than the permitted limit for applying sewage sludge to land. Generally, applications of sewage sludge of up to 40 g kg resulted in a considerable increase in all of the morphometric parameters and biomass of cucumbers in contrast to plants grown on the control soil. Nevertheless, the cucumber shoot height; root length; number of leaves, internodes and fruits; leaf area; absolute growth rate and biomass decreased in response to 50 g kg of sewage sludge. All of the heavy metal concentrations (except the Cu, Zn and Ni in the roots, Mn in the fruits and Pb in the stems) in different cucumber tissues increased with increasing sewage sludge application rates. However, all of the heavy metal concentrations (except the Cr and Fe in the roots, Fe in the leaves and Cu in the fruits) were within the normal range and did not reach phytotoxic levels. A characteristic of these cucumbers was that all of the heavy metals had a bioaccumulation factor <1.0. All of the heavy metals (except Cd, Cu and Zn) had translocation factors that were <1.0. As a result, the sewage sludge used in this study could be considered for use as a fertilizer in cucumber production systems in Saudi Arabia and can also serve as a substitute method of sewage sludge disposal. Graphical Abstract The effects of different sewage sludge amendment rates on the heavy metal bioaccumulation, growth and biomass of cucumbers.

The evaluation of sewage sludge application as a fertilizer for broad bean (Faba sativa Bernh.) crops

“…In our investigation, soil OM increased with the rate of SS addition, achieving its greatest value with the maximum dose (150 t/ha). Eid, El‐Bebany, et al., ; Eid, Alrumman, et al., verified that the addition of SS to soil cultivated with spinach and cucumber promoted a rise in the soil content of OM. The soil OM content in nonamended soil was 1.3%, compared to 1.6, 1.7, 1.9, 2.1, and 2.4%, which corresponded to 1.2‐, 1.3‐, 1.5‐, 1.6‐, and 1.9‐fold increases, respectively, at 30, 60, 90, 120, and 150 t/ha SS amendment rates.…”

“…However, SS may contain high levels of pollutants, either organic and/or HMs (Rastetter & Gerhardt, ). Therefore, an eco‐friendly management strategy of SS is required (Eid, Alrumman, et al., ) because it may lead to environmental pollution if not dealt with appropriately (Singh & Agrawal, ).…”

“…In the following 32 years, it is expected that the request for food will growing by more than 60% as the overall population will increase to 9.3 billion in 2050 (Lee, ). Additionally, in arid and semi‐arid countries, for example, Saudi Arabia, the warm dry summers with a continued drought and inadequate procedures for soil conservation resulted in diminishing soils OM (Eid, Alrumman, et al., ). These conditions have affected the biological, chemical and physical features of the soil, which led to soil deterioration in terms of structure and fertility (Wei & Liu, ).…”

“…Thus, agricultural soil amendment with SS can enhance soil physical characteristics and fertility, which ultimately improve crop production (Koutroubas, Antoniadis, Fotiadis, & Damalas, ). Furthermore, Eid, El‐Bebany, et al., ; Eid, Alrumman, et al., have suggested that SS could provide a appreciated fertilizer, in the forthcoming, that might promote yield, growth, and plant constituents of crops. Additionally, according to Brown and Leonard (), reutilizing organic carbon present in SS is significant for the carbon sequestration fixed from the atmosphere in soils, and it is important for the mitigation of climate change.…”

A Review on Sewage Sludge (Biosolids) a Resource for Sustainable Agriculture

“…Eljarrat et al (2008) reported the significant content of Polybrominated diphenyl ethers (PBDE) in sewage sludge ranged from 197 to 1185 ng/g dry weight (dw) and further in the sewage sludge amended soil PBDE levels in soils ranged between 21 and 690 ng/g dw. Moreover, levels about 200 ng/g dw have been reported in Eid et al (2017) sludge from Sweden and The Netherlands (Sellstrom et al, 1999;de Boer et al, 2002), and around 500 ng/g dw for samples collected in Denmark (Christenson et al, 2003). Higher concentrations were found in USA, with values ranging from 1000 to 2290 ng/g dm for tri-to hexa-BDEs, and from 85 to 4890 ng/g dm for deca-BDE-209, with the mean values of approximately 1600 and 1000 ng/g, respectively (Hale et al, 2003).…”