Mixing of plant litters strengthens their remediation effects on crude oil-contaminated soil

Potential effects of soil petroleum contamination on decomposition of Artemisia annua plant litter

“…According to our previous studies, the concentration of petroleum in soil is 11 440–44 720 mg kg −1 . 26…”

“…Additionally, the soil samples were analyzed through the Soxhlet extractor method 24 to confirm the absence of petroleum contaminants. The crude oil used was procured from the local oilfield, with the basic physical and chemical properties of the soil and petroleum previously described by Zhang et al 26 The prepared soil was then divided into four subsamples. Three of them were treated with petroleum to create contaminated soils with three concentrations: 15, 30, and 45 g kg −1 , designated as lightly, moderately, and seriously contaminated soil, respectively.…”

“…The study area is situated within the oilelds of Yanchang County, Shaanxi, China (E 109°33 0 -110°30 0 , N 36°14 0 -36°46 0 ), falling within the loess hilly region of the Loess Plateau. The climate in this area is characterized as a warm temperate semiarid monsoon continental climate, with specic temperature, precipitation, and light parameters previously described by Zhang et al 26 The soil in this region is classied as Calcic Cambisols according to the FAO soil classication system. Natural vegetation comprises forest steppe, predominantly featuring Artemisia spp., Bothriochloa ischaemum, and Lespedeza davurica.…”