A simple equation has been developed for describing the bidirectional reflectance of some vegetative canopies and bare soil surfaces. The equation describes directional reflectance as a function of zenith and azimuth view angles and solar azimuth angle. The equation works for simulated and field measured red and IR reflectance under clear sky conditions. Hemispherical reflectance can be calcula...

In this paper, in 2012 and 2013 two of the Three-River Headwaters Region of soil total-nitrogen, data combined ASD FieldSpec 4 made by America spectroradiometer measured spectral reflectance of soil sample chamber data model MSLR and ANN methods modeling. The spectral data is mainly composed of original spectral reflectance(REF) through nine point weighted moving average obtaining four forms of...

Abstract. The reflectance spectra of the soil samples are influenced by soil particle size. Elimination of this effect requires a calibration model to remove the effect of soil particle size. Therefore, this study aimed to investigate the effects of soil particle size on reflectance spectra of sandy soil samples and to produce a particle size calibration model for the spectra of a sandy soil sa...

Visible, Near and Short Wave Infrared (VNSWIR) diffuse reflectance spectroscopy (350 nm to 2500 nm) has been proven to be an efficient tool to determine the Soil Organic Carbon (SOC) content. SOC assessment (SOCa) is usually done by using calibration samples and multivariate models. However one of the major constraints of this technique, when used in field conditions is the spatial variation in...

A two-stream description of the interaction of radiation with vegetation and soil is tested with experimental data for a corn canopy. The results indicate that the two parameters of the theory (reflectance of a dense canopy and the attenuation coe~cient for radiation in the canopy) can be estimated for the Thematic Mapper spectral bands. A collection of soil reflectance data is used to develop ...

Reliable information on soil status and crop health is crucial for detecting and mitigating disasters like pollution or minimizing impact from soil-borne diseases. While infestation with an aggressive soil pathogen can be detected via reflected light spectra, it is unknown to what extent hyperspectral reflectance could be used to detect overall changes in soil biodiversity. We tested the hypoth...

This study was conducted to investigate the effects of soil moisture content on reflectance spectra of sandy soils with different phosphorus (P) concentrations using UV-VIS-NIR reflectance spectroscopy. Sandy soils with average particle size of 250 μm were used. Investigations were conducted at 0, 12.5, 62.5, 175, 375, 750, and 1000 mg/kg phosphorus application rates. Three soil moisture conten...

The purpose of this paper is to analyse the impact of surface soil moisture on spectral reflectance in the optical domain [0.4 – 15 μm]. This work is based on lab spectral reflectance measurements of many bare soils at different moisture contents. Firstly, a classification of bare soil samples is performed according to their spectral signatures: five classes are then defined. Secondly, the soil...

Soil contamination by arsenic and heavy metals is an increasingly severe environmental problem. Efficiently investigation of soil contamination is the premise of soil protection and further the foundation of food security. Visible and near-infrared reflectance spectroscopy (VNIRS) has been widely used in soil science, due to its rapidity and convenience. With different spectrally active soil ch...

A previously developed reflectance-based crop coeJficient (Kcr) for corn, estimated from the normalized difference vegetation index (ND VI), has been shown to overestimate the basal crop coe~cient (KeQ for corn by 24% or more when used with a dark-colored soil. This overestimation occurs because the NDVI produces larger index values for the same vegetation amount over dark backgrounds. Thus, th...