| Popis: |
The objectives for this study were (1) to investigate the potential usefulness of growing-season spectral measurements in order to predict end-of-season winter wheat dry-matter production and (2) to evaluate straw-total-dry-matter relationships and their possible usefulness in residue management decisions. A field experiment was located on a Williams loam soil (fine—loamy mixed, Typic Argiborolls), 11 km northwest of Sidney, Montana. “Roughrider”, a winterhardy hard red winter wheat (Triticum aestivum L.) cultivar, was seeded to seven stands of from 0 to 100% (100%=1,570,000 plants per hectare). On clear mornings, a handheld radiometer was used to measure reflectances, corresponding to the Landsat multispectral scanner bands. Grain and straw yield data were collected to determine the degree of relationship between grain and dry matter. Relationships between the normalized difference vegetation index [ND7=(MSS7− MSS5)/(MSS7 + MSS5)] as determined from late tillering until the beginning of flowering growth stages, and end-of-season straw and total dry matter clearly established the potential of remote sensing for predicting straw and total dry-matter yield. Predicting dry-matter production is useful in providing an estimate of residue production for erosion control and as a potential source for feed and energy. |
