Submitted to: Agronomy for Sustainable Development
Publication Type: Peer reviewed journal
Publication Acceptance Date: 4/3/2004
Publication Date: 1/14/2005
Citation: McMurtrey, J.E., Daughtry, C.S.T., Devine, T.E., Corp, L.A. 2005. Spectral detection of crop residues for soil conservation from conventional and large biomass soybean. Agronomy for Sustainable Development. 25:25-33. Interpretive Summary: A cost effective method for ameliorating soil erosion in grain crops is to evenly distribute the mature crops plant residue over the soil surface at harvest. In order to assess appropriate soil conservation practices, a rapid effective method of detecting the distribution and amount of crop residues on the soil surface is needed. Soybeans have long been considered poor producers of adequate amounts of crop residue for soil conservation purposes. A spectrally derived cellulose absorption index (CAI) was tested to determine its value as a remote sensing method over soybean plot areas with known above ground crop residue biomass and coverage.
Technical Abstract: A spectrally derived cellulose absorption index (CAI) was tested to determine its value as a remote sensing method over soybean (Glycine max (L.) Merr.) plot areas with known above ground crop residue biomass and coverage. New types of large biomass soybean (LBS) are being bred and tested at the Beltsville Agricultural Research Center, Maryland. LBS can grow to heights of 1.8-meters (6 ft.) or more and can produce significantly increased amounts of crop residue compared to conventional cultivars. LBS can produce 2963 kg more crop residue biomass per hectare (1.3 tons / A) than conventional soybeans and can provide a mean increase of 45 percent more crop residue cover than conventional soybean types. The comparison of LBS versus conventional soybeans was used to spread the range of crop residue production for testing of the CAI remote sensing method. CAI spectrally sensed measures of crop residue were significantly associated with the physical ground measurements of crop biomass at harvest and percent cover after over wintering. Significant correlation between CAI and biomass (r2 = 0.66) and, CAI and two measures of percent cover (r2 = 0.74) were found. Soybean crop residue biomass amounts and coverage could be detected by remote sensing methods.