Pandit Govind Ballabh Pant Memorial Lecture: II

scientific and technological inputs taking into account the indigenous knowledge
(Khoshoo, 1991). This is particularly true for Himalayan agroecosystems.
The concept of agro-ecosystems aims at giving ecological orientation to
the agriculture systems so as to reap the maximum benefit from the available
resources under a particular set of growing conditions. In simpler words, it aims
at using land, water and vegetation for sustainable production/productivity.
Before attempting this, there is need to have precise information on various agroecological
parameters like soil, rainfall, temperature, water, potential evaporation,
etc.
However, there are not many worthwhile examples where agricultural
scientists have looked into the possibility of application of ecological principles in
the agricultural production system(s), and conversely where ecologists have
been involved in agricultural sciences. This is the result of an unwitting schism
between agriculture and ecology. The nearest the two have gone is in the case of
Integrated Pest Management.
The attempt has to match the following aspects for achieving optimum
results.
- Identify and map climate of an area based on temperature regime,
seasonally of rainfall, soil etc.
- Select crop species out of those that are suited to a particular
ecological regime.
- Work out the growing periods based on data on rainfall and potential
evapotranspiration.
- Determine specific crop and cultivar requirements for the particular
growing period.
This would enable to delineate agroecosystems as land units in terms of
major climate and growing period which is ecologically suitable for definite crops
and cultivars. There are there major components of agro-ecosystems: soil-scape
(physiography and soils), beioclimate (rainfall, temperature, vegetation, potential
evapotranspiration, soil storage). Based on these, Sehal et.al (1990) have
identified 21 agro-ecological regions, five of which fall in the Himalaya. Cental to
the whole concept is soil, climate and land-use. These need to be periodically
appraised. Implicit in this is that proper crop species would have to be identified
so as to develop suitable cropping patterns, keeping in view the local practices
and wisdom.
A brief description of the five agroecosystems in the Himalaya, as identified by
Sehgal et.al (1990) is given below:
North-Western Himalaya: This agroecosystem is located in cold and arid
regions with shallow skeletal soils. It covers Ladakh and Gilgit. It covers an area of 15.6
Mha.
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