Removal of abamectin and conventional pollutants in vertical flow constructed wetlands with Fe-modified biochar

Abstract

To improve the ability of constructed wetlands to remove abamectin (ABM) and nutrients, the influence of four different substrates on constructed wetlands was studied.

Recent Advance on the Effects of Biochar on Constructed Wetlands: Treatment Performance and Microorganisms

“…Under low-temperature conditions, the performance of CWs to treat pollutants will be greatly reduced, and the addition of biochar alone cannot achieve a good effect. A large number of studies have found that modified biochar has a good effect on the treatment of pollutants in CWs at low temperatures [53]. The adsorption capacity of biochar for nitrate is limited, and modified methods are usually used to improve the adsorption capacity of biochar in CWs [54].…”

A Literature Review of Wetland Treatment Systems Used to Treat Runoff Mixtures Containing Antibiotics and Pesticides from Urban and Agricultural Landscapes

“…Only one study in 2020 considered a runoff mixture containing antibiotics, nutrients, pesticides, and other pharmaceuticals [103]. Of these studies that looked at mixtures, only 16 specifically analyzed the impact on nitrogen removal in the presence of different contaminants [23,30,58,59,67,97,102,103,[112][113][114]120,131,169,179,181,201]. Thus, the data shows that only recently have some of these contaminants started to be studied individually, in the case of antibiotics, but also as mixtures.…”

“…used in 11% of the studies (Table 6). It is important to note that not all studies used wetland plants [43,83,89] or identified the specific plant species within the wetland system [148,159,179]. Also, not all primary studies that specified the plant species present in the wetland system analyzed the impact of phytoremediation as a removal mechanism [21,173,205].…”

“…This included studies that compared different media types [67,104,170] or analyzed the amount of contaminant sorbed to the wetland media by determining the concentrations of contaminants [74,87,135,170,229] or determining sorption isotherm coefficients for the media [137,196,198]. The different media types found in the primary studies included biochar [59,170,179,192], straw [133,134], compost [170], different types of soil [67,145,196,197], gravel [104, 161,229], pebbles [179], zeolite [59,114,147,218], and cobbles [104].…”

“…The increased microbial activity enhanced the removal capabilities for CUPS and antibiotics [59,60], with microbial degradation being a leading mechanism for removal [194]. However, the microbial communities were impacted by the substrate [59,194], the type and concentration of contaminants present [58,114,179], and the physicochemical properties of the water [179]. In particular, Lu et al (2021) reported the presence of sulfamethoxazole improved interactions for denitrifying bacteria, but also decreased network complexity and microbial interaction on the whole molecular network, thus altering the community structure of nitrogen-transforming microorganisms [114].…”