Effect of Biochar Addition on Phosphorus Adsorption Characteristics of Red Soil

Abstract

Phosphorus (P) sorption by red soil is strong due to its acidic pH and high content of metal oxides. Biochar addition may increase the availability of red soil P by altering P sorption characteristics. This study examined the influences of doping ratios of the biochar, phosphate concentration, solution pH, and biochar-derived dissolved black carbon (DBC) on P sorption in red soil. The specific sorption mechanisms were explored using 3D fluorescence spectroscopy, infrared spectroscopy, and zeta potential analysis. The results show that the bioavailable P content in the biochar-amended red soil increased to 1.92 mg kg−1, which is an increase of 255% compared with the original red soil. With the increase in the doping ratio of biochar, the maximum sorption amount of P initially decreased and then increased. Moreover, the pH value and the content of the dissolved organic carbon (DOC) of the red soil were effectively elevated by biochar addition. The increase in the DOC content is likely caused by the DBC released from biochar. As the soil pH value increased, the amount of P sorption was reduced due to electrostatic repulsion. P sorption by the red soil decreased with the increasing DBC concentration. The humic acid-like substances in DBC can compete with phosphate for soil sorption sites, leading to a decrease in P absorption. This study demonstrates that the addition of biochar affects P sorption of the red soil mainly by changing its physicochemical properties or by releasing DBC to occupy the sorption sites.

Rhizosphere Microbe Affects Soil Available Nitrogen and Its Implication for the Ecological Adaptability and Rapid Growth of Dendrocalamus sinicus, the Strongest Bamboo in the World

“…The natural distribution of D. sinicus is limited to the red soil habitat of Yunnan, China [30]. Red soil develops in warm temperate and humid climates and is characterized by low pH and soil nutrient availability [2]. In this study, the soil samples displayed a slightly acidic condition, with pH values ranging from 5.58 to 6.13.…”

“…However, there were few studies on the relationship between red soil micro-organisms and rapid growth of woody bamboos. Red soil was characterized by low nutrient availability [2], but D. sinicus growing on the red soil exhibited a substantial aboveground biomass [30]. It was therefore of interest to see how the barren red soil provided sufficient available nutrients for D. sinicus during its rapid growth period.…”

“…Red soil is an important soil type in southern China. Due to soil parent material, high temperature, high humidity and other climatic factors, red soil is generally characterized by high Fe contents, low pH, low contents of organic carbon and soil nutrient elements, as well as strong erosion [1,2]. Nitrogen (N) is one of the major elements essential for plant growth [3].…”

Influence of biochar amendment on removal of heavy metal from soils using phytoremediation by C. roseus and Chrysopogon zizanioides

“…Moreover, other molecular organic acids released by biochar might compete for the adsorption sites. The dissolved black carbon released with biochar amendment increases the total organic carbon, which competes with the phosphate ions for sorption sites (Wu et al, 2022). In all cases, the nutrient concentrations have increased from the initial stage, which can be attributed to plant growth and biomass production.…”

Perbaikan Beberapa Sifat Tanah Sulfat Masam dengan Penerapan Biochar Sekam Padi Teraktivasi Diperkaya Trichoderma sp. dan Limbah Agroindustri untuk Mendorong Hasil IR Zink

“…Abdillah & Widiyastuti (2022) Mekanisme adsorbsi kimia dari biochar juga berperan dalam menekan kembalinya logam agar tidak berdampak pada penurunan pH tanah saat terjadi reduksi (Yang et al, 2021). Chang et al (2021) dan (Yulnafatmawita et al, 2023) Penerapan biochar mampu menurunkan degradasi hara makro dan mikro akibat kelarutan, perlindian, fiksasi dan dominasi logam (Alotaibi et al, 2021;Bilias et al, 2023;Neththasinghe et al, 2023;Rasuli et al, 2022;Wu et al, 2022;Xiu et al, 2023). Namun…”