Question

classify farming on the basis of main sources of moisture for crops.

Answer 1

On the basis of main source of moisture for crops, the farming can be
classified as irrigated and rainfed. There is difference in the nature of irrigated
farming as well based on objective of irrigation, i.e. protective or productive.
The objective of protective irrigation is to protect the crops from adverse
effects of soil moisture deficiency which often means that irrigation acts as a
supplementary source of water over and above the rainfall. The strategy of
this kind of irrigation is to provide soil moisture to maximum possible area.
Productive irrigation is meant to provide sufficient soil moisture in the cropping
season to achieve high productivity. In such irrigation the water input per unit
area of cultivated land is higher than protective irrigation. Rainfed farming is
further classified on the basis of adequacy of soil moisture during cropping
season into dryland and wetland farming. In India, the dryland farming is
largely confined to the regions having annual rainfall less than 75 cm. These regions grow hardy and drought resistant crops such as ragi, bajra, moong, gram and guar (fodder crops) and practice various measures of soil moisture
conservation and rain water harvesting. In wetland farming, the rainfall is in
excess of soil moisture requirement of plants during rainy season. Such
regions may face flood and soil erosion hazards. These areas grow various
water intensive crops such as rice, jute and sugarcane and practice
aquaculture in the fresh water bodies.
Rain-dependent areas can be broadly split into two: ‘dry lands’, which
receive less than 750 mm of rain a year; and rainfed areas, which receive
more than 750 mm. Comprising arid and semi-arid ecosystems, dry lands
stretch from Gujarat in the west till Eastern Madhya Pradesh; and from
Rajasthan till the southern tip of India.