Acta Agriculturae Zhejiangensis ›› 2026, Vol. 38 ›› Issue (1): 114-125.DOI: 10.3969/j.issn.1004-1524.20250361

• Environmental Science • Previous Articles     Next Articles

Effects of green manure returning methods on soil inorganic phosphorus fractions and phosphorus uptake by wheat

GUO Ranran1(), XU Ke1, LI Zhengpeng2, YAN Qingbiao2, LI Rong2, HAN Mei2,*()   

  1. 1. College of Agriculture and Animal Husbandry, Qinghai University, Xining 810016, China
    2. Academy of Agriculture and Forestry Sciences, Qinghai University, Xining 810016, China
  • Received:2025-05-06 Online:2026-01-25 Published:2026-02-11

Abstract:

To investigate the effects of green manure returning to the field on soil inorganic phosphorus (P) fractions and P uptake by wheat, a split-plot field experiment was conducted. The main plots were assigned to two chemical fertilizer application regimes: no chemical fertilizer (N0) and chemical fertilizer application with 157.5 kg·hm-2 N and 78.75 kg·hm-2 P2O5 (N1). The subplots were subjected to three green manure management practices: no green manure (G0), returning of the root stubble of green manure to the field (G1), and green manure incorporation (G2). Following wheat harvest in July 2024, the content of soil total P, available P, and various inorganic P fractions was determined, as well as soil phosphatase activities, wheat grain yield, and P accumulation in different parts of wheat. It was shown that returning the green manure to the field could enhance soil inorganic P content. Compared with the N1G0 treatment, the total soil inorganic P content in the N1G1 and N1G2 treatments increased significantly (p<0.05) by 16.4% and 18.9%, respectively. In comparison with the N0G0 treatment, the total soil inorganic P content in the N0G1 and N0G2 treatments was significantly elevated by 39.6% and 21.5%, respectively. Compared with the N1G0 treatment, the N1G2 treatment resulted in significant increases in the contents of dicalcium phosphate (Ca2-P), octacalcium phosphate (Ca8-P), apatite (Ca10-P), aluminum-bound P (Al-P), and occluded P (O-P) by 25.6%, 48.8%, 11.9%, 16.3%, and 19.3%, respectively. Compared with the N1G0 treatment, the N1G1 treatment significantly increased the contents of Ca8-P, Ca10-P and O-P by 53.3%, 10.6% and 19.5%, respectively. With chemical fertilizer application, green manure returning to the field significantly improved the activities of soil neutral and acid phosphatases. Compared with the N1G0 treatment, the neutral phosphatase activity in N1G1 and N1G2 increased by 3.3% and 4.5%, respectively, while the acid phosphatase activity was enhanced by 19.3% and 31.2%, respectively. Without chemical fertilizer application, the N0G2 treatment significantly increased the activities of soil alkaline, neutral, and acid phosphatases by 21.7%, 6.0%, and 50.8%, respectively, as compared with the N0G0 treatment. Additionally, the N0G1 treatment led to a significant 12.0% increase in acid phosphatase activity compared with the N0G0 treatment. Green manure returning to the field also exerted a significant positive effect on wheat yield. Compared with the N1G0 treatment, the wheat yield in N1G1 and N1G2 increased by 5.8% and 8.7%, respectively. In contrast to N0G0, the wheat yield in N0G1 and N0G2 was elevated by 83.0% and 84.3%, respectively. Furthermore, appropriate treatments with green manure returning to the field facilitated P accumulation in different parts of wheat at both the flowering and maturity stages. In conclusion, green manure returning to the field promoted wheat P uptake by optimizing soil inorganic P fractions and enhancing soil phosphatase activity, thereby achieving the synergistic improvement of wheat yield and P uptake. Under the experimental conditions, green manure incorporration with chemical fertilizer application was the optimal choice for improving soil P availability and promoting wheat growth in Qinghai.

Key words: green manure returning to the field, inorganic phosphorus fraction, wheat, phosphatase activity, phosphorus accumulation

CLC Number: