Establishment of Crops under Minimal Soil Disturbance and Crop Residue Retention in Rice-Based Cropping System: Yield Advantage, Soil Health Improvement, and Economic Benefit

Abstract

Minimum soil disturbance and increased crop residue retention practices are promising options to enhance soil organic matter, nutrient concentration and crop yield. However, the potentials of the practices in improving soil properties, increasing crop yield and in ensuring economic return have not been tested in the monsoon rice (Oryza sativa L.)‑lentil (Lens culinaris L.)/wheat (Triticum aestivum L.)‑jute (Corchorus culinaris L.) cropping systems on seasonally flooded lowlands of the Eastern Gangetic Plain of South Asia. A field trial for consecutive three years was conducted in the Gangetic Plains of Bangladesh to evaluate the effects of zero tillage (ZT), strip-tillage (ST), bed planting (BP) and conventional tillage (CT) with two residue retention levels (RL—a low level similar to current farmers’ practice and RH—increased retention) on soil properties, yield and economic return. Between rice and jute crops, lentil was grown for the 1st and 2nd years and wheat for the 3rd year during the dry winter season. The ST and BP performed better than the CT and ZT in terms of yield of rice and lentil, whereas ST and ZT performed better than other practices in the case of jute. Higher residue retention (RH) increased crop yield for all the years. The highest rice equivalent yield (sum of 3 crop yields, expressed as rice yield) and the greatest benefit-cost ratio (BCR) were recorded with ST and RH. The increased yield in the ST was associated with reduced soil bulk density (BD), while ST with RH increased soil water (SW) and decreased penetration resistance (PR) of soil. Compared to CT, minimum soil disturbance of ZT and ST increased soil organic matter (SOM) stock by 24% and 23%, respectively; total nitrogen (TN) by 23.5% and 18.4%, respectively; extractable sulphur (S) by 21% and 18%, respectively; whereas Zinc (Zn) concentrations increased by 53% and 47%, respectively, in the upper 0–5 cm soil depth. Accumulation of extractable P, S and Zn in the 0–5 cm depth of soil followed the sequence as ZT > ST > BP > CT practice. The higher amount of residue retention significantly increased SOM, TN and extractable P, K, S and Zn concentrations at 0–5 cm and 5–10 cm soil depths. The 3-year study suggests that ST with RH is a potential crop management approach for the seasonally flooded rice-lentil/wheat-jute cropping systems to enhance soil nutrients status, crop yield and farm economy.

Carbon and Nitrogen Mineralization in Dark Grey Calcareous Floodplain Soil Is Influenced by Tillage Practices and Residue Retention

“…A cropping systems-based experiment was conducted in a farmer's field (23 • 39 45 N, 89 • 29 39 E) at Baliakandi Upazila, Rajbari district, Bangladesh from July 2012 to July 2015, as described by [13]. The experiment site is under Agro-Ecological Zone 12 (Low Ganges River Floodplain) with a well-drained Calcareous Dark Grey Floodplain Soil (FAO: Chromic-Calcaric Gleysols).…”

“…Before starting the first crop, the initial soil properties of the experimental field were analyzed at 0-5, 5-10, and 10-15 cm soil depths. Initial soil properties can be found in [13]. In the initial soil the SOC stocks were 4.76, 4.36, and 3.95 t ha −1 , total N were 0.430, 0.398, 0.364 t ha −1 , and microbial biomass carbon (MBC) were 122, 115, and 110 mg kg −1 , respectively, for 0-5, 5-10, and 10-15 cm soil depth.…”

“…For jute, all of the fallen leaves were dropped on the soil during its growing period regardless of residue treatment. The details of residue retention can be found at Salahin et al [13].…”

“…Land preparation for ZT, ST, BP, and CT are reported in detail by [13]. The crop management and rates of chemical fertilizers for component crops along with their application methods in the cropping sequence are detailed in Salahin et al [13]. Weeds, insect and disease control was done as and when required following the standard safety guidelines.…”

“…Commonly, wetland rice is grown each year in a rotation with upland crops (pulses/ oilseeds/vegetables/wheat/maize/potatoes, etc.,) in the Gangetic plains of South Asia. Novel resource-saving technologies are being developed for most of the crops in the ricebased cropping systems in the ecosystem [8,[11][12][13]. Across the Gangetic plain, the adoption of CA practices by farmers is on the rise [11,14,15].…”