IAPRS & SIS, Vol.34, Part 7, “Resource and Environmental Monitoring”, Hyderabad, India, 2002 
  
  
3.1.1 B2-V Semi- stabilized to stabilized high dunes and 
major obstacle dunes: An area of 5,796 ha has been mapped 
under this category, which includes stabilized as well semi- 
stabilized high sand dunes ranging more than 40 meters high 
from mean ground level. Parabolic and coalesced parabolic are 
dominant sand dunes occurring in this region (Anon., 1982). 
Upper flanks and leeward side of such dunes are generally bare 
with loose sand and subject to moderate to severe wind erosion. 
Towards windward side of such dunes owned by farmers, 
rainfed farming is done up to the middle flanks during the 
favourable rainfall years. Bajra, guar and moth are the 
important crops produced in such lands. Major parts of such 
dunes, which are government holdings, are active and highly 
degraded. The slopes of the windward side, leeward side and 
crest are about 8%, 24% and 40% respectively. Soils of such 
dunes are light yellowish brown, uniformly sandy and very 
deep. The soil contains 2.5 to 5% clay, 1.5 to 3 % silt and 70 to 
80 % fine sand. These soils can retain 40 to 50 mm of moisture 
per meter depth. 
3.1.2 B2-E Semi-stabilized and stabilized moderately high 
dunes and minor obstacle dunes: This category of dunes 
occur in 21,500 ha or 6.14 % of the total tehsil area and 28.84 
% of the total wastelands. These dunes occupy a large area of 
western and northern parts of the region. Such dunes comprise 
parabolic, coalesced parabolic, transverse and longitudinal 
dunes ranging between 20 to 40 meters height above mean 
ground level. Most of these dunes are active and bare on the 
upper flank, leeward side and left and right arms of the flanks. 
These sand dunes can be classified into land capability class VI 
ec. The slopes of the crest, leeward and windward flanks are 
40%, 24% and 8% respectively. Active parts of the dunes have 
loose sand. The soils have 0.04 to 0.15 % organic carbon, 8-15 
kg of P, Os / ha and 70-150 kg K,O per hectare. Majority of 
such dunes are private holdings. 
3.1.3 B2-D Semi-stabilized to stabilized low dunes, highly 
hummocky and shrub- coppice dunes: Sand dunes of this 
category occur in 12,346 ha or 3.53 per cent of the total tehsil 
and 16.56 per cent of the total wastelands. The height of these 
dunes ranges from 5 to 20 meters. Shrub-coppice dunes (2 to 5 
meters) and barchan dunes are also included in this category. 
Barchan dunes are devoid of any vegetative cover. Such dunes 
are fairly distributed throughout the region. These lands are best 
suited for agri-silvi-pasture and agro-forestry. 
3.1.4 B3-V Closely spaced inter-dune area: An area of 871 ha 
or 0.26 % of the total tehsil area and 1.17 % of the total 
wastelands, has been mapped under this category. These 
wastelands are dominantly occurr in north- western part of the 
region where intensity of medium to high dunes is more. These 
interdune areas are infested with hummocks, low dunes and 
shrub-coppice dunes which are subject to slight to moderate 
wind erosion / deposition. Such areas can be managed by 
farmers themselves by providing technical support from 
research organizations, NGO and government departments and 
by adopting suitable cropping pattern, growing of grasses and 
introduction of improved farming practices 
3.2 ABC CLASSIFICATION OF SANDY WASTELANDS 
IN ARID RAJASTHAN 
3.2.1 A - Dune Complex in Hyper Arid Region (Rainfall « 
100 mm): The entire dune complex (sand dunes, inter-dune and 
sandy undulating area) in «100 mm average annual rainfall 
zone has been classified under category A. (Fig 2). This is 
hyper arid region where most of the terrain is devoid of 
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vegetative cover. Giving a bare and barren outlook, most of the 
dunes, inter-dune and hummocks are active with loose sand and 
subject to severe and very severe wind erosion/ deposition 
hazard (Chatterji and Kar1992). Low and erratic rainfall, high 
evaporation loss, high wind speed, extremes of seasonal 
temperatures and very poor infrastructure developments are 
major constraints making area unfit for human dwelling. 
Longitudinal dunes are common but parabolic, coalesced 
parabolic, transverse and barchans dunes are also seen. The 
stabilization, management and development of such region are 
very expensive, uneconomic and unsustainable. 
3.2.2 B - Sandy Areas in Arid Region (Rainfall > 100mm): 
B1 Active Sand Dunes (100-250 mm rainfall zone) 
B1-V High to very high sand dunes: Because of their large 
size (up to 500 m wide and 4 km long), height (40 m to 110 m), 
and high slopes, these sand dunes require government 
intervention for development. It is not possible for the poor 
farmer alone to manage such vulnerable dunes and tackle the 
menace of wind erosion and deposition. These sand dunes 
constitute both individual and government holdings and occur 
in Barmer (Chatterji and Joshi, 1989), eastern part of Jaisalmer 
and western part of Jodhpur and Bikaner (Anon.1974) districts. 
Excepting their lower base, the entire parts of dunes are highly 
active and unstabilized. Most of these dunes are of old system 
comprising parabolic, coalesced parabolic, longitudinal and 
transverse types. Sizes of sand grains of such dunes vary from 
0.15 to 0.07 mm. The fluvial action has created rills and gullies 
of different dimensions. Soils are very deep and fine sand to 
loamy fine sand, pH 7.8, slight calcareous at surface and 
moderately calcareous in sub soil zone and well drained. Slope 
varies from 5 % in windward side to 40 % towards leeward 
side. Upper flank and leeward side of the dunes are highly 
active with loose sand. 
B1-E Moderately high dunes: In 100 to 250 mm annual 
rainfall zone, even moderately high dunes are highly vulnerable 
to wind erosion, sifting of sand dunes and sand accumulation 
on agricultural fields, roads, rails and settlements. Such 
categories of sand dunes are concentrated in Barmer, eastern 
part of Jaisalmer and western part of Bikaner and Jodhpur 
districts. Longitudinal, parabolic, transverse and high obstacle 
dunes are grouped under this category. The slope of such dunes 
varies from 5 to 20 per cent with very deep fine sand to loamy 
fine sandy soils. Majority of such dunes are private holdings. 
The average length and width of coalesced parabolic dunes are 
1 to 2 km and 200 to 300 meters respectively. The slopes are 
generally 1 to 3 degree towards windward side and 20 to 22 
degree towards leeward side. Longitudinal dunes generally 
occur along the direction of the prevailing south- west wind. 
These are 1.5 to 8 km in length and 200 to 220 meters in width. 
Transverse dunes are found across the path of prevailing south- 
west winds with 45 to 40 degree orientation. Slopes of these 
dunes vary from 16 to 2096 towards leeward side, 8 to 1994 
along the flanks and 1 to 2% along the windward side 
B1-D Low sand dunes, inter-dune and hummocky area: 
Low dunes, inter-dune and hummocks occurring between 100 
to 250 mm annual rainfall zone, are designated under this 
category. Heights of such dunes vary form 5 to 20 meters. 
Parabolic, barchans, obstacles and shrub coppice dunes are 
encountered within this region. These wastelands can be 
managed and put to sustainable use like silvi-pasture and agri- 
silvi-pasture by providing technical and financial support to the 
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