作者
Zhijie Ren,Xiaojie Han,Haoxiang Feng,Lifang Wang,Geng Ma,Junhong Li,Jun-Jie Liu,Weihua Tian,Xinhua He,Yanan Zhao,Chenyang Wang
摘要
Although conservation tillage has been widely implemented to address the challenge to improve crop yield and soil quality with fewer environmental costs, its long-term effects on crop yields and soil stoichiometry balance remain uncertain. Here, four different long-term (17-year) tillage practices (conventional tillage (CT), deep scarification (DS), no tillage (NT), and ridge tillage (RT)) were conducted in northern China to evaluate their effects on crop yield, soil nutrients, C sequestration, and soil stoichiometry. The conservation tillage (DS, NT, and RT) increased the recent 5-year average yields by 12.2 %–20.1 % compared with CT, respectively. RT showed the highest C sequestration potential of 10.0 t/ha, followed by DS and NT (6.0 t/ha and 4.4 t/ha, respectively). The DS, NT, and RT enhanced soil available N and K with the best effect for NT, but DS reduced soil total and available P. The conservation tillage significantly increased the C:N, C:P, C:K, and N:P ratios, indicating it sustained soil balanced stoichiometry. Correlation analysis indicated crop yield was closely related to soil C:N, C:P, C:K, and N:P. The structural equation model revealed that the C, N, and P affected C:N and C:P ratios, thus improving crop yield under long-term conservation tillage. In summary, long-term conservation tillage improves soil stoichiometry balance and thus crop yields with great C sequestration potential to achieve sustainable agricultural management in rain-fed farmland.