Geoscience Reference
In-Depth Information
Carbon sequestration by organic agriculture as
compared to chemical farming
% Increase in C sequestration
Agro
ecosystems
Range
Mean
Arid
12-25
17.2
Semi-arid
8-19
13.5
Sub-humid
6-15
10.2
Humid
5-14
7.4
Improvement in microbial activity in organic versus
chemical f
farming
% Increase over chemical
farming
Agro
ecosystems
Range
Mean
Arid
4-59
21.5
Semi-arid
6-61
23.7
Sub-humid
8-62
25.9
Humid
9-63
26.5
10.5
Climate variability and food production
Climatic variability and occurrence of extreme events are major
concerns for the Indian subcontinent. There is a need to quantify
the growth and yield responses of important crops and also iden-
tify suitable land use options to sustain agricultural productivity
under this large range of climatic variations. In India, the analy-
sis of seasonal and annual surface air temperatures (Pant and
Kumar, 1997) has shown a significant warming trend of 0.57°C
per hundred years. The warming is found to be mainly contrib-
uted by the post-monsoon and winter seasons. The monsoon
temperatures do not show a significant trend in any major part
of the country. Similar warming trends have also been noticed
in Pakistan, Nepal, Sri Lanka and Bangladesh. The rainfall fluc-
tuations in India have been largely random over a century, with
no systematic change detectable in the summer monsoon sea-
son. However, during recent years areas of increasing trend in
the seasonal rainfall have been found along the west coast, north
Andhra Pradesh and North-West India and areas of decreasing
trend over East Madhya Pradesh, Orissa and North-East India.
