Synthetic Humic Acids Solubilize Otherwise Insoluble Phosphates to Improve Soil Fertility.

Fan Yang,Markus Antonietti,Nadezda V Tarakina,Qing Du,Jingpeng Song,Guixiang Li,Shuaishuai Zhang

doi:10.1002/anie.201911060

Abstract

Artificial humic acids (A‐HA) made from biomass in a hydrothermal process turn otherwise highly insoluble phosphates (e.g. iron phosphate as a model) into highly available phosphorus, which contributes to the fertility of soils and the coupled plant growth. A detailed electron microscopy study revealed etching of the primary iron phosphate crystals by the ‐COOH and phenolic groups of humic acids, but also illustrated the importance of the redox properties of humic matter on the nanoscale. The combined effects result in the formation of then bioavailable phosphate nanoparticles stabilized by humic matter. Typical agricultural chemical tests indicate that the content of total P and directly plant‐available P improved largely. Comparative pot planting experiments before and after treatment of phosphates with A‐HA demonstrate significantly enhanced plant growth, as quantified in higher aboveground and belowground plant biomass.

Highlights

Artificial humic acids (A-HA) made from biomass in a hydrothermal process turn otherwise highly insoluble phosphates into highly available phosphorus, which contributes to the fertility of soils and the coupled plant growth
A detailed electron microscopy study revealed etching of the primary iron phosphate crystals by the -COOH and phenolic groups of humic acids, and illustrated the importance of the redox properties of humic matter on the nanoscale
Wang et al.[11] reported that addition of humic acids to soil together with P fertilizer significantly increased the amount of directly available water soluble phosphate and strongly retarded the formation of mineralized phosphate: The P uptake and crop yield increased by 25 %, especially long after fertilization

Summary

Introduction

Abstract: Artificial humic acids (A-HA) made from biomass in a hydrothermal process turn otherwise highly insoluble phosphates (e.g. iron phosphate as a model) into highly available phosphorus, which contributes to the fertility of soils and the coupled plant growth. Wang et al.[11] reported that addition of humic acids to soil together with P fertilizer significantly increased the amount of directly available water soluble phosphate and strongly retarded the formation of mineralized phosphate: The P uptake and crop yield increased by 25 %, especially long after fertilization.

Results

Conclusion