Objectives of the project

Long-term single chemical fertilizers application has emerged serious land degradation problems including soil organic matter depletion and structure deterioration in intensive wheat-maize system in the North China Plain (NCP). Lime concretion black soil, as the main cultivated soil and typical low-medium yielding farmland in this region, was characterized by sticky and heavy texture, poor soil structure and low soil organic matter. Utilization of fertilizer substitution by biogas slurry irrigation is a promising approach to soil fertility and aggregate improvement, especially in the context of lacking sources of organic fertilizer in agriculture and massive biogas slurry production in husbandry. A representative field experiment was manipulated in a consecutive wheat-maize rotation for 5 years to address the variation of soil physiochemical properties and aggregation characteristics with different biogas slurry substitution proportions. The results confirmed that biogas slurry irrigation could influence soil properties and change aggregate characteristics of lime concretion black soil in the NCP. Furthermore, the physiochemical properties improvement and aggregate stability enhancement are determined by biogas slurry substitution proportion. Soil bulk density declined, and water holding capacity, organic matter, available phosphorus available potassium contents and C/N ratio increased with substitution proportion increased. Half alternative with biogas slurry irrigation acquired the strongest aggregate stability parameter and soil pH as well as total nitrogen among different treatments. These results suggested that lime concretion black soil in NCP are readily amenable to improve by biogas slurry application in less than 5 years, which could be a priority for coordinated agriculture and animal husbandry in this region. Our PhD student Xihuan Zhang work with this topic. In Ukraine we would like to use the similar technology and we start from the green house experiment and then microfield experiment.

Key words: biogas slurry; organic fertilizer; physiochemical properties; soil fertility; soil microbiome

Multidisciplinary research team composition:

Elina Zakharchenko, main coordinator, PhD, associate professor, Department of Agrotechnologies and Soil science, Sumy National Agrarian University

Xihuan Zhang, co-reseacher, PhD student, Department of Agrotechnologies and Soil science, Sumy National Agrarian University

Degtyarjov Vasyl, co-reseacher, Dsc, Professor, Head of Soil Science Department, Kharkiv National Agrarian University named by V.V. Dokuchaev (from 7.09.2021 State Biotechnological University)

Zlenko Iryna, co-reseacher, PhD, associate professor, Department of Ecology, Dnipro State Agrarian and economic University