Use of Hyperspectral and Biochemical Data from Black Spruce Needles to Map Soils at a Forest Site in Manitoba

Biochemical assessment of Black Spruce (Picea mariana Mill.) needles collected from trees near Thompson, Manitoba reveals that there are concentrations of potassium (K) in them which reflect the K distribution in the rooting zone. Exchangeable potassium amounts ranged from low to high at lowland/upland locations and were found to be associated with either poorly or well-drained brunisol and luvisol soils. An ammonium-acetate extraction performed on soil samples established that K is in an available form for uptake by the Spruce trees overlying them. A relatively high degree of correlation exists between plant K content and its magnitude in the soil (r=0.868). Comparison of mean spectral signatures between needles with low and high K concentrations showed statistically significant differences in their response patterns in the green and infrared edge wavelength regions. Pearson Product Moment correlation analysis of foliar K content and original and first derivative spectra found that these differences were, to a considerable degree, attributable to K content variability. These relationships indicate that hyperspectral scrutiny of Spruce needles, in conjunction with biochemical examination, may be a useful method for indirectly mapping upland and lowland soils in this area. 1998, Taylor & Francis Group, LLC. All rights reserved.

Use of Hyperspectral and Biochemical Data from Black Spruce Needles to Map Soils at a Forest Site in Manitoba Academic Article