Biochar and Manure Co-Application Increases Rice Yield in Low Productive Acid Soil by Increasing Soil pH, Organic Carbon, and Nutrient Retention and Availability

Dong Liang; Yunwang Ning; Cheng Ji; Yongchun Zhang; Huashan Wu; Hongbo Ma; Jianwei Zhang; Jidong Wang

doi:10.3390/plants13070973

Biochar and Manure Co-Application Increases Rice Yield in Low Productive Acid Soil by Increasing Soil pH, Organic Carbon, and Nutrient Retention and Availability

Plants (Basel). 2024 Mar 28;13(7):973. doi: 10.3390/plants13070973.

Authors

Dong Liang^{1

2}, Yunwang Ning^{1

2}, Cheng Ji^{1

2}, Yongchun Zhang^{1

2}, Huashan Wu^{1

2}, Hongbo Ma^{1

2}, Jianwei Zhang^{1

2}, Jidong Wang^{1

2}

Affiliations

¹ Scientific Observatory and Experimental Station of Arable Land Conservation of Jiangsu Province, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China.
² Key Laboratory of Saline-Alkali Soil improvement and Utilization (Coastal Saline-Alkali Lands), Ministry of Agriculture and Rural Affairs, Nanjing 210014, China.

Abstract

In recent years, overuse of chemical fertilization has led to soil acidification and decreased rice yield productivity in southern China. Biochar and manure co-application remediation may have positive effects on rice yield and improve acid paddy soil fertility. This study was conducted to understand the effects of co-application of wood biochar and pig manure on rice yield and acid paddy soil quality (0-40 cm soil layers) in a 5-year field experiment. The experiment consisted of six treatments: no biochar and no fertilizer (CK); biochar only (BC); mineral fertilizer (N); mineral fertilizer combined with biochar (N + BC); manure (25% manure N replacing fertilizer N) combined with mineral fertilizer (MN); and manure combined with mineral fertilizer and biochar (MN + BC). Total nitrogen application for each treatment was the same at 270 kg nitrogen ha^-1y^-1, and 30 t ha^-1 biochar was added to the soil only in the first year. After five years, compared with N treatments, N + BC, MN, and MN + BC treatments increased the rice yield rate to 2.8%, 4.3%, and 6.3%, respectively, by improving soil organic matter, total nitrogen, and available phosphate under a 0-40 cm soil layer. MN + BC had the strongest resistance to soil acidification among all the treatments. The interaction between fertilizers and biochar application was significant (p < 0.05) in rice yield, soil electrical conductivity (10-20 cm), and soil available phosphate (20-40 cm). Principal component analysis indicated that the effect of manure on soil property was stronger than that of biochar in the 0-40 cm soil layer. The overall rice yield and soil fertility decreased in the order of biochar + mineral fertilizer + manure > mineral fertilizer + manure > biochar + mineral fertilizer > mineral fertilizer > biochar > control. These results suggest that biochar and manure co-application is a long-term viable strategy for improving acid soil productivity due to its improvements in soil pH, organic carbon, nutrient retention, and availability.

Keywords: low-productive soil; pig manure; rice; rice–soil interactions; soil layers; wood biochar remediation.

Grants and funding

This study was supported by Jiangsu Agricultural Science and Technology Innovation Fund (CX(21)-1009), Key Research and Development Program of Jiangsu Province (BE2021378), the National Natural Science Foundation of China (42207353), and the Earmarked Fund for CARS-10-Sweetpotato.