The Effects of Partial Substitution of Fertilizer Using Different Organic Materials on Soil Nutrient Condition, Aggregate Stability and Enzyme Activity in a Tea Plantation

Chengyi Huang; Kairui Zhang; Wentao Guo; Huijuan Huang; Zhangyong Gou; Liu Yang; Yian Chen; Kokyo Oh; Conggang Fang; Ling Luo

doi:10.3390/plants12223791

The Effects of Partial Substitution of Fertilizer Using Different Organic Materials on Soil Nutrient Condition, Aggregate Stability and Enzyme Activity in a Tea Plantation

Plants (Basel). 2023 Nov 7;12(22):3791. doi: 10.3390/plants12223791.

Authors

Chengyi Huang^{1

2}, Kairui Zhang¹, Wentao Guo¹, Huijuan Huang¹, Zhangyong Gou¹, Liu Yang¹, Yian Chen¹, Kokyo Oh³, Conggang Fang⁴, Ling Luo²

Affiliations

¹ College of Water Conservancy and Hydropower Engineering, Sichuan Agricultural University, Ya'an 625014, China.
² College of Environmental Sciences, Sichuan Agricultural University, Chengdu 611130, China.
³ Saitama International Center for Environmental Science, Saitama 330-9301, Japan.
⁴ Chengdu Land and Resources Information Center, Chengdu 611130, China.

Abstract

Fertilization plays a crucial role in enhancing tea production. However, it has been demonstrated that the long-term single application of chemical fertilizer will reduce soil nutrient content and the formation of soil aggregates, which is not conducive to the sustainable development of soil and agriculture. Many studies have shown that partial substitution of chemical fertilizer with organic fertilizer can improve soil physicochemical properties and soil nutrient content. This study compared the effects of different organic materials as substitutes for chemical fertilizer. We partially replaced chemical fertilizer with rabbit manure, wine lees and rapeseed cake, amounting to 30% of the total annual nitrogen application in the field experiment, and we set nine different fertilization methods to assess and analyze the soil nutrient condition, aggregate stability and enzyme activity. The results showed that the experimental soil aggregate mean weight diameter (MWD) and geometric mean diameter (GMD) were significantly increased compared with control (p < 0.05); the aforementioned fertilization methods also decreased the soil aggregate fractal dimension (D), disruption rate (PAD), average weight-specific surface area (MWSSA) and soil erodibility factor (K). The application of the fertilizer containing organic materials and microbial agent increased soil organic carbon (SOC) by 20.7% to 22.6% and total nitrogen (TN) by 34.6% to 38.1%; it also significantly promoted sucrase, urease and protease activities in all aggregate sizes (p < 0.05) and increased the 2-5 mm aggregate content. The correlation coefficients between the SOC and the enzyme activities were 0.18-0.95, and most of them showed an extremely significant positive correlation (p < 0.01). In conclusion, the application of fertilizers containing organic materials and microbial agents can improve soil aggregate stability, aggregate enzyme activity and soil structural stability.

Keywords: organic materials; replacement of chemical fertilizer; soil aggregate enzyme activity; soil nutrients; tea plantation.

Grants and funding

This research was funded by Key Science and Technology Program of Ya’an City, grant number 2019yyjskf11, the National Nature Science Foundation of China, grant number 41701294, and Agricultural Science and Technology Program of Yibin City, grant number 2022NY013.