Carbon Sink Capacity and Agronomic Productivity of Soils of Semiarid Regions of India - Principles of Sustainable Soil Management in Agroecosystems - page 434

TABLE 16.4
Critical Yield Gaps (q ha -1 ) in Major Rainfed Pulse Crops

Yield Potential on
Research Plots

Yield in FLDs at
Farmers Fields

National
Average Crop

Chickpea 20-22 15-18 8.06

Pigeon pea (early) 15-17 12-15 7.97

Pigeon pea (late) 20-25 20-22 -

Mung bean 11-12 9-10 3.81

Urd bean 10-12 8-9 4.40

Field pea 20-22 15-18 10.34

Lentil 15-18 12-14 7.32

Source: Chatuverdi, S.K. and M. Ali, Poor man's meat needs fresh fillip. In The
Hindu Survey of Indian . Agriculture 2002 , 63-69. Chennai, India, 2002.
Note: FLD, front-line demonstration.

16.5 POOR SOIL HEALTH AND MULTINUTRIENT DEFICIENCIES
Therefore, soils under rainfed agriculture are not only thirsty but also hungry. Soil
quality is severely degraded because of low levels of SOM in dry regions of India.
Soils of arid and semiarid regions in India are highly diverse and comprise Vertisols
and Vertic subgroups, Alfisols, Oxisols, Inceptisols, Aridisols, Entisols, and so forth.
Furthermore, there exists a large variation in rainfall, which ranges between 400 and
1500 mm per annum. Accordingly, the length of the growing season ranges between
60 and 180 days and sometimes even lower. Above all, soils are highly degraded,
extremely depleted of their SOM concentration (Figure 16.6), and are multinutrient
deficient ( Table 16.5 ). The SOC concentrations in some regions of rainfed agriculture

0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0

FIGURE 16.6 Rainfed regions in arid and semiarid tropical India are low in SOC. (From
Srinivasarao, Ch., and K.P.R. Vittal, Indian J Fertil , 3, 37-46, 2007.)