# Special Issue on \"Ecotechnological Green Approaches to Environmental Remediation and Restoration\"
###### Abstract
Phosphorus, a chemical analog of As, can control As motility in soil and As uptake in rice through competition for soil particle uptake sites, thanks to competition between P and As for uptake and the opposing effect of P on root-to-shoot As transfer. Se (IV) is transported to plant roots via phosphate and silicon transporters, and Se (VI) is transported to plant roots via sulphate transporters before competing with arsenic through the known routes. Ca participates in signaling various physiological and biochemical processes as a secondary messenger that mediates several cell and plant growth prospects and responds to various stresses including As toxicity. [PERSON] et al. (contribution 4) studied heavy metal (Cu, Pb, Cd, Cr, Ni and Zn) contamination in cropland soils, its spatial distribution, and its controlling factors in 12 different cities in Shandong Province, China,. The correlation analysis and factor analysis indicated that Cu/Ni/Zn and Pb/Cd were caused by a broad range of human activities, and that proper management of human activities is warranted to mitigate the risk of cropland soil becoming toxic and to ensure environmental health and safety. [PERSON] et al. (contribution 5) showed that viewer grass (_Chrysopogon zizainoides_ L. [PERSON]) can serve the dual purpose of phytoremediation and biofel feedstock generation in metal-contaminated soils. In a greenhouse experiment, they assessed the effectiveness of viewer grass in phytostabilizing copper (Cu)-contaminated soil as well as the potential of the harvested lignocellulosic biomass for downstream bioethanol production. The results obtained from the study with vetiver grass subjected to dilute acid pretreatment, enzymatic hydrolysis, and optimization of fermentation process parameters using response surface methodology (RSM) suggested that the lignocellulosic composition of the grass was altered suitably, showing an appreciable decrease in lignin but an increase in hemicellulose and cellulose content, which led to greater ethanol yield and volumetric productivity from the hydrolysates produced from the metal-stressed biomass. [PERSON] et al. (contribution 6) investigated the use of extracellular biosurfactants (sophorolipids) derived from the yeast _Candida bombicola_ CB2107 in the bioremediation of kerosene-contaminated soils for their subsequent potential application as a substitute for chemical surfactants, thus acting as \"green\" reagents for extracting petroleum hydrocarbons from contaminated soil. The results showed that although sophorolipids have the potential to replace synthetic surfactants, the properties and performance of the biosurfactants vary widely depending on the yeast species/strains and the growing conditions during production. [PERSON] et al. (contribution 7) examined the potential of an extracellular polymeric substance (EPS) produced by _Bacillus licheniformis_ strain KX657843 isolated from earthworm (_Metaphire posthuma_) gut in the adsorption of Cu(II) and Zn(II) from aqueous solution and in flocculation. The negatively charged functional groups of carbohydrates and protein moiety of the EPS were found to be capable of binding and removal of heavy metals through electrostatic interactions. Such a thermostable EPS from earthworm gut bacteria was championed as an effective agent for environmental remediation of heavy metals and as an emerging eco-friendly biofloculant that can potentially replace synthetic flocculants in various applications, such as water/ wastewater treatment and industrial waste treatment. [PERSON] et al. (contribution 8) assessed highly salinity-tolerant bacterial strains for the biodegradation of broad-spectrum antibiotics like sulfamethoxazole (SMX), which is extensively used in intensive coastal aquaculture (_Chanos chanos_) to fight bacterial infections. The antibiotics end up in fish (milkfish) pond sediments, resulting in pollution in rivers and oceans from the discharge of aquaculture wastewater.