IAPRS & SIS, Vol.34, Part 7, "Resource and Environmental Monitoring", Hyderabad, India,2002 
SPECTRAL REFLECTANCE CHARACTERISTICS OF SOILS OF UTTARANCHAL 
STATE, INDIA 
R.K. Saxena', K.S. Verma', Rajeev Srivastava", Janardan Yadav?, N.K. Patel*, R.A. Nasre?, A.K. Barthwal®, A.A. Shiwalkar®, 
: S.L. Londhe* 
“ National Bureau of Soil Survey and Land Use Planning, Amravati Road, Nagpur, India (rksaxena, ksverma, rajeev, akbarthwal, 
rnasre)@nbsslup.mah.nic.in 
? Defence Agricultural Research Laboratory, Pithoragarh, Uttranchal, India 
* Space Application Centre, Ahmedabad, India (nkp. sac, ajayshiwalkar) yahoo.com 
KEYWORDS: Spectral library, Soil albedo, Soil characteristics, Hill & mountain soils 
ABSTRACT: 
The paper discusses the physico-chemical characteristics of some dominant soils of Uttranchal state vis-à-vis their spectral 
reflectance characteristics in the spectral range 350- 1800 nm. The spectral reflectance measurements of collected soil samples were 
taken under natural light condition (Sun) using ASD Spectroradiometer operating in the spectral range 350 to 1800 nm. White 
Spectralon plate was used as calibration standard. The soils of Uttranchal state, in general, have loamy sand to silt loam and silty 
clay loam texture. The soil colour varies from very dark grayish brown (10YR 3/2) to light yellowish brown (10YR 6/4) and reddish 
yellow (7.5 YR 6/6). Soil pH ranges between 5.2 and 6.5 whereas organic carbon content varies from 0..92 to 8.32 per cent. The soil 
spectral reflectance varies with the variation in soil physical and chemical characteristics. In general, the soil spectral reflectance 
showed negative trend with increase in soil organic carbon content. The paper also discusses the results of the correlation carried out 
between spectral reflectance data obtained in different spectral regions with different soil properties. 
1. INTRODUCTION 
The interaction of solar radiation with soil and its spectral 
behaviour is important to understand soil quality and soil 
mapping. Soil colour, particle size, organic matter, iron content, 
soil moisture influence on the spectral reflectance behaviour of 
the soils (Baumgardner et al. 1970; Bowers and Hanks, 1965; 
Da Costa, 1979; Hoffer and Johannsen, 1969; Mathews et al. 
1973; Montgomery, 1976. Recent research has demonstrated 
the ability of reflectance spectroscopy to provide non- 
destructive rapid prediction of soil physical, chemical and 
biological properties in the laboratory (Ben-Dor and Banin, 
1995; Janik et al. 1998; Reeves et al. 1999). Condit (1970, 
1972) measured spectral reflectance of 160 soil samples and 
classified all spectra into three general types with respect to 
their curve shape. Concept of spectral reflectance libraries is 
gaining momentum. Recently, Shepherd and Walsh (2002) 
developed reflectance spectral libraries for characterization of 
soil properties. 
The present paper highlights the salient morphological, physical 
and chemical characteristics of soils of Uttranchal state and 
their spectral behaviour in spectral range of 350 to 1800 nm for 
developing spectral reflectance library. 
2. MATERIALS AND METHODS 
2.1 General Description of the Area 
The Uttranchal state lies between 28°45” to 31°27°N latitude 
and 77°40’ to 81°E longitude and is bounded by Nepal in the 
East, China in the North, Himachal Pradesh in the West and 
Uttar Pradesh in the South. Ninety per cent area of the state is 
hilly and altitude ranges from 200 to 7800 metres above MSL. 
Physiographically the area is divided into 4 physiographic 
divisions, viz. i) Indo-Gangetic plain including Tarai in the 
South, ii) Siwaliks/Outer Himalayas; iii) Lesser Himalayas and 
iv) Greater Himalayas. Vast variation in altitude has bearing on 
   
climatic conditions including rainfall, temperature regime and 
snow fall. The soil moisture regimes are ustic, udic and cryic. 
The soil temperature regime ranges from hyperthermic in 
Lesser Himalayas to thermic/mesic in Greater Himalayas. High 
reaches are covered with snow and have frigid soil temperature 
regime. 
2.2 Methodology 
Forty Soils, occurring on different altitudinal zones, having 
wide variation in their physical and chemical characteristics 
were studied representing the soil order Entisols, Inceptisols, 
Mollisols and Alfisols of Soil Taxonomy. The locations of 10 
representative sites are given in table 1. 
Table 1. Location of soil site 
  
  
  
  
  
  
  
  
  
  
  
Site Soil District Lat./ Altitude 
No Long. (m) 
1 Karan Chamoli 30°17’N 832 
Prayag 79°16’E 
2 Baijnath Bageshwar | 29°54’N 1144 
1936'E 
3 Mahergaon | Nainital 29°22’N 1485 
1932 E 
4 Pithoragarh | Pithoragarh | 29?35' N 1498 
80° 13’ E 
5 Pandukesh | Chamoli 30°38’ N 1958 
war 98 32" E 
6 Chaukori Bageshwar 29°50’ N 1980 
80°01’ E 
7 Auli Chamoli 30°31’ N 2684 
79°34’ E 
8 Malari Chamoli 30°40’ N 3185 
79°33. E 
9 Badrinath Chamoli 30°43’ N 3105 
19°29’ E 
10 Shelang Chamoli 30°31’ N 2684 
79°34’ E 
  
    
  
  
  
  
  
  
   
    
  
  
   
    
  
  
  
    
     
  
  
  
  
  
  
   
  
    
   
   
    
    
    
    
    
    
     
       
     
     
   
    
  
    
     
    
   
    
    
    
    
   
  
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