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PUNJAB

Geographical Position and climate

Punjab is one of the smallest states of India representing 1.5% geographical area and 2.5% of the
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population of India. The geographical area of the state is 50376 km . It lies within latitudes of
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29 55’ to 32 30’ north and longitudes of 73 55’ to 76 50’ east in the Indo-Gangetic plains of
northern India.Except for a strip of the Shivalik Hills along its eastern border, the entire area is
flat alluvial plain with height above the sea level ranging from 180 to 290 meters. The Punjab
state has been mainly differentiated in three agro-climatic zones mainly on the basis of rainfall
amount, viz. sub-mountaneous undulating zone, central plain zone and south-western zone. The
normal annual rainfall in sub-mountainous undulating, central plain and south-western zone
is1070, 750 and 530 mm, respectively, whereas, the normal monsoon rainfall for these regions is
849, 604 and 406 mm, respectively. The monsoon rain occurring during July to September with
pre-monsoon showers during the month of June constitutes 80% of the annual rainfall.Sub-
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mountain undulating region, the average maximum temperature of 40-41 C is recorded during
first fortnight of June, where as minimum temperature is recorded during the month of January.
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The average minimum temperature varies from 6-7 C. Whereas central plain region: The mean
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maximum temperature recorded during first fortnight of June is 42 C in the southern half and
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41 C in the northern half. The mean minimum temperature varies from 7 C in the southern half
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to 4 C in the northern parts of the region. As the latitudinal extent is not much in western region,
there is not much temperature variation from south to north.
Soils

The soils of Punjab have developed on alluvium brought from the Himalayas by the rivers of
Indus system during Pleistocene and Recent times. The different types of soils of Punjab have
been classified as i) soils of arid and hot south-western zone (0.85 m ha), ii) soils of semi arid
(semi dry) and less hot central plain zone (3.69 m ha), iii) soils of semi-arid (sub moist) and less
hot (lower kandi) zone (0.42 m ha) and iv) soils of sub humid (sub moist) and warm (upper
kandi) zone (0.07 m ha). The high nutritional requirements of paddy and wheat have exhausted
the Punjab soils of vital nutrients. Majority of the soils in the state have low N supplying
capacity as 61% soils are rated as low (<0.4%) and 36% are medium (0-4-0.7%) in organic
carbon. Contrary to common belief, intensive cultivation of rice-wheat has rather improved soil
organic carbon (SOC) status by 38% during the last 25-years. In addition, soil pH declined by
0.8 units from 8.5 in 1981/82 to 7.7 in 2005/06 that has positive implications for availability of
P, Zn, Fe and Mn. Majority of the soils in the state have medium to high content of plant
available P and K. While 36% soils are deficient in available P, only 7% are deficient in
available potassium.The status of plant-available K in soil has virtually remained unaltered,
mainly because of the presence of K-bearing minerals in soil and addition of K through irrigation
water. About 25% soils in the state are deficient in available S. Another important issue that
could constrain sustainable crop production is the availability of micronutrients in soils. While
the Mn deficiency has increased from 3 to 11%, zinc deficiency has rather decreased from 43%
in the year 1990 to 22% during 2002-2007.