“…Nevertheless, agricultural utilization of sewage sludge to mudflats may contain some toxic elements (e.g., heavy metals) to plants and contaminate groundwater after leaching (McLaren, Clucas, Taylor, & Hendry, 2004;Richards, Steenhuis, Peverly, & Mcbride, 1998). Many previous studies on the use of sludge in degraded farmland (Gorbacheva, Kikuchi, & Gorbachev, 2009;Mamedov et al, 2016;Marques, Jimenez, Perez-Rodriguez, Garcia-Ormaechea, & Bienes, 2005;Ojeda, Alcaniz, & Ortiz, 2003;Sort & Alcaniz, 1996), forest (Dzeletovic, Filipovic, Stojanovic, & Lazarevic, 2009;Hueso-Gonzalez, Martinez-Murillo, & Ruiz-Sinoga, 2014), and quarry soil (Lozano, Fernandez, & Alvarez, 1999;Sort & Alcaniz, 1999) showed that farmland use of sludge could increase heavy metal uptake and accumulation in crop plants (Bozkurt & Yarilgac, 2003;Smiri, Elarbaoui, Missaoui, & Ben, 2015) and leaching loss of heavy metals in soil leachate (Cerezo, Marcos, & Rodriguez, 1999;McLaren et al, 2004;Paramasivam, Sajwan, & Alva, 2006). Transport and fate of the metals in mudflat salt-soil amended by sludge are quite different from those in farmlands due to difference in soil properties including salinity, pH, structure, microbial flora and background level of heavy metals, and so forth (Mallol, 2006;Singh & Kar, 2001).…”