Conservation agriculture improves yield and potassium balance in intensive rice systems

• Published in: Nutrient cycling in agroecosystems Vol. 128; no. 2; pp. 233 - 250
• Main Authors: Islam, M. J., Cheng, M., Kumar, U., Maniruzzaman, M., Nasreen, S. S., Hossain, M. B., Haque, M. E., Jahiruddin, M., Bell, R. W., Jahangir, M. M. R.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-04-2024; Springer Nature B.V
• Subjects: Agricultural conservation; Agricultural production; Agriculture; Biomedical and Life Sciences; Cereal crops; Conservation; Crop production; Crop residues; Cropping systems; Crops; Leaching; Life Sciences; Original Article; Potassium; Residues; Retention; Rice; Soil conservation; System yield; Conservation agriculture; Strip planting; K fertilizer; K balance; Residue retention
• ISSN: 1385-1314; 1573-0867
• DOI: 10.1007/s10705-024-10348-7

Intensive rice-based systems are mining soil potassium (K) due to negative K balances. Conservation Agriculture (CA) practices may increase yield and economic return of rice-based systems but there is limited understanding of their effects on K pools and balances. This study evaluated crop productivity and K input–output balances under contrasting rice-based intensive cropping and long-term CA. The comprised three factors- (a) soil disturbance (strip planting, SP and conventional tillage, CT); (b) residue retention (low, LR, 20 cm by plant height and high, HR, 50 cm) and; (c) K application-100% K (recommended dose, RD), 50–75% K of RD (low dose, LD), and 125–150% K of RD (high dose, HD). The long-term experiment initiated in 2010 and soil samples were collected in 2018 after 24th crop and 2020 after 30th crop of triple cropping system. The K balances for the 2018 cropping cycle were negative, ranging from − 47 to − 82 kg ha
−1
 yr
−1
. In the 2020 cycle, when the high K dose was increased from 125 to 150% of RD, the negative K balance was significantly reduced in SP-HR-HD (− 19 kg ha
−1
 yr
−1
) while 23–35% higher cropping system yield was achieved. Leaching was a significant K loss pathway. Overall results indicate that minimum soil disturbance and increased crop residue retention had significant positive effects on cropping system yield and K balance. However, to achieve neutral K balance in intensive rice-based cropping systems, increased recycling of K from crop residue, higher doses of K addition or lower K losses are needed.