Feasibility of conservation agriculture in the Amu Darya River Lowlands, Central Asia

Human-driven land degradation threatens economic and environmental sustainability of irrigated agricultural production such as in Central Asia. Many current challenges can be eased by implementing Conservation Agriculture (CA), with however unknown financial consequences under the predominating irrigated conditions. We applied the linear programming to compare costs and benefits of four CA production systems, which are cotton-based rotation systems including (i) cotton-cotton and (ii) cotton-wheat-maize rotations under conventional tillage (CT), as well as (iii) cotton-cover crop-cotton, and (iv) cotton-wheat-maize rotations with mulch cover (crop residue retaining) and both rotations under permanent-bed planting (PB) with minimum tillage. All systems were subjected to six levels of land quality and a series of crop pricing schemes. Data were extracted from empirical research on CA in Uzbekistan, complemented with data on input and output prices from surveys. The findings underpinned the financial advantages of more diversified cropping systems (cotton-wheat-maize) over the crop monoculture (cotton-cotton-based system). Crop cultivation on marginal land was unprofitable under CT. In contrast, crop production under PB could generate profits even on croplands with a lower productivity level considered. It is argued that PB with crop residue retaining and applied in cotton-wheat-maize rotation shows most promise for improving crop yields and income.