Soil amino compound and carbohydrate contents influenced by organic amendments

Authors: He, Zhongqi; Olk, Daniel - Dan; Waldrip, Heidi

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 2/21/2014
Publication Date: 5/1/2014
Citation: He, Z., Olk, D.C., Waldrip, H.M. 2014. Soil amino compound and carbohydrate contents influenced by organic amendments. In: He, Z., Zhang, H., editors. Applied Manure and Nutrient Chemistry for Sustainable Agriculture and Environment. Amsterdam, the Netherlands: Springer. p. 69-82.

Interpretive Summary: Animal manure plays an important role in soil fertility and plant nutrient management. This is especially true where the effective use of nutrient sources, such as organic and low-input agriculture, is crucial to maintaining productivity. Amino acids and amino sugars compounds (ACs) are the major ingredients of organic N in animal manure. This chapter includes two parts: a literature review that provides up-to-date information on the relevant research, and a case study based on greenhouse manure experiment with ryegrasses. The case study demonstrated that poultry manure increased soil extractable ACs when added at a high application rate and depressed them when added at a low application rate. The increase in extractable ACs at the high rate was further amplified in the soils taken from the rhizosphere. The presence of ryegrass decreased concentrations of ACs and carbohydrates, more so through decrease in microbial compounds. Finally, the chapter recommends more types of organic amendments be evaluated for their impacts on soil amino compound and carbohydrate levels, and the relationships in changes between the two types of compounds. Such cumulative knowledge would provide a basis for establishing their specific contributions to soil N and C dynamics over the course of agricultural seasons and beyond.

Technical Abstract: Amino compounds (i. e. amino acids and sugars), and carbohydrates are labile organic components and contribute to the improvement of soil fertility and quality. Animal manure and other organic soil amendments are rich in both amino compounds and carbohydrates, hence organic soil amendments might affect soil processes through these labile components. This chapter first reviews the advances in research on soil concentrations of amino compounds and carbohydrates as impacted by animal manure and other organic amendments. The published papers are mainly on the amino compounds and carbohydrate changes in long term field trials and laboratory or greenhouse incubations, tracking the fate of amendment-derived amino compounds and carbohydrates in soils. To investigate the amino compound and carbohydrate changes in the short-term (16 weeks), we present a greenhouse pot study (4-16 weeks) which demonstrated that poultry manure increased extractable amino compounds when applied to soil at a high rate, and depressed them at a low application rate. The increase at the high rate was further amplified in rhizospheric soils. Whereas microbial activities promoted C and N mineralization, the presence of ryegrass decreased concentrations of amino compounds and carbohydrates, more so through a decrease in microbial compounds. Finally, we recommend more types of organic amendments be evaluated for their impacts on soil amino compound and carbohydrate levels, and the relationships in changes between the two types of compounds. Such cumulative knowledge would provide a basis for establishing their specific contributions to soil N and C dynamics over the course of agricultural seasons and beyond.