Spectral reflectance of turfs can provide estensive information concerning color, pests, quality, nutrition and water stress. In the research carried out in Pisa in July 2003, the spectral reflectance of a Cynodon dactylon x transvaalensis Burtt. Davy (cv Santa Ana) turf fertilized with increasing nitrogen rates (from 0 to 450 kg ha-1 di N) was evaluated. Reflectance measurements were performed with LICOR 1800 spectroradiometer and a LICOR 1800-06 telescope (1.5 m height) with a view angle of 15°.Many vegetation indices were calculated combining bands of the same spectrum. Phytometric characteristics (quality, color, height, clipping biomass, nitrogen content) of the turf were evaluated after spectral measurements. Nitrogen rate and bands showed a strong regression with the PAR (R2=0.93) many bands and vegetation indices (R2=0.98). The general formula was y= a+bx+cx2. Infrared bands showed a weaker association with N rate.Color, quality, height, clipping biomass, height and clipping nitrogen content were highly correlate with many bands and vegetation indices.The trial showed how an in-depth analysis of radiation reflected by a bermudagrass turf provides extensive information on the modifications induced by nitrogen fertilization on the canopy.
Indici vegetazionali per la valutazione dello stato nutritivo di un tappeto erboso di gramigna
GROSSI, NICOLA;VOLTERRANI, MARCO;MIELE, SERGIO
2005-01-01
Abstract
Spectral reflectance of turfs can provide estensive information concerning color, pests, quality, nutrition and water stress. In the research carried out in Pisa in July 2003, the spectral reflectance of a Cynodon dactylon x transvaalensis Burtt. Davy (cv Santa Ana) turf fertilized with increasing nitrogen rates (from 0 to 450 kg ha-1 di N) was evaluated. Reflectance measurements were performed with LICOR 1800 spectroradiometer and a LICOR 1800-06 telescope (1.5 m height) with a view angle of 15°.Many vegetation indices were calculated combining bands of the same spectrum. Phytometric characteristics (quality, color, height, clipping biomass, nitrogen content) of the turf were evaluated after spectral measurements. Nitrogen rate and bands showed a strong regression with the PAR (R2=0.93) many bands and vegetation indices (R2=0.98). The general formula was y= a+bx+cx2. Infrared bands showed a weaker association with N rate.Color, quality, height, clipping biomass, height and clipping nitrogen content were highly correlate with many bands and vegetation indices.The trial showed how an in-depth analysis of radiation reflected by a bermudagrass turf provides extensive information on the modifications induced by nitrogen fertilization on the canopy.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
