Characteristics of Copper Sorption by Various Agricultural Soils in China and the Effect of Exogenic Dissolved Organic Matter on the Sorption |
| |
Authors: | Xiuhong Ding Wen Ma Xianming Huang Wei Guo Renqing Wang Yuncong Li |
| |
Institution: | 1. Environment Research Institute, Shandong University, Jinan, China;2. Chemistry and Chemical Engineering, Qilu Normal University, Jinan, China;3. Shandong Agricultural Environmental Protection and Rural Energy Station, Jinan, China;4. Department of Soil and Water Science, Tropical Research and Education Center, University of Florida, Homestead, FL, USA |
| |
Abstract: | To explore the effect of exogenic dissolved organic matter (DOM) on Cu(II) sorption in agricultural soils, 26 agricultural soils were collected across China. Exogenic dissolved organic matter, extracting from wheat straw (DOMW) and swine manure (DOMS), respectively, were added to the soils to conduct a series of batch sorption and characterization experiments. The solid-liquid partition coefficient (Kd) ranged from 0.02 to 76.46 L g?1, suggesting different Cu(II) sorption on various soils. PCA analysis indicated that pH, free Fe/Al oxides, carbon, and total Cu content had a significant positive relationship with the Cu(II) sorption, respectively. And the contribution rate of pH was the highest (38.15%). Moreover, DOM markedly inhibited the Cu(II) sorption in alkaline soils while promoted the Cu(II) sorption in acidic soils, which were interacted by the soil properties and DOM characteristics. The effect of DOMS on Cu(II) sorption were more obvious than DOMW, which were further confirmed by Fourier transform infrared (FTIR) spectroscopy. FTIR also showed Cu(II) was primarily adsorbed on the specific functional groups, such as CO, OH, and CO, providing direct evidences for the binding of Cu(II) with DOM. This study can guide the rational use of organic fertilizers, and also provide baseline knowledge for the prevention and control of soil pollution. |
| |
Keywords: | Cu(II) sorption dissolved organic matter agricultural soils partition coefficient soil properties |
|
|