Remote sensing of crop residue and tillage practices: Present capabilities and future prospects

Sustainable agricultural management is essential not only to maintain productivity of current farmlands, but also to conserve natural environments. Records of agricultural activities are required to assist rapid assessment of agricultural lands, and thus, designation of management plans and policies. By the 1980s, when unfavorable environmental impacts of conventional tillage practices were widely recognized, agronomists introduced conservation tillage to benefit soils and agricultural environments, and soon began programs to monitor adoption of conservation tillage practices. The role of remote sensing in acquiring this information has been increasing because remote sensing technologies can provide the broad scope and the ability to collect sequential imagery to estimate trends and patterns of adoption of alternative tillage practices. This review encompasses comparisons of remote sensing techniques with more conventional methods for surveying and estimating tillage status, applications of remote sensing technologies, data processing and analysis, validation and field data collection, impacts of terrain, spectral and spatial resolution, timing and temporal detail, and prospects of future instruments.