Carbon Sink Capacity and Agronomic Productivity of Soils of Semiarid Regions of India - Principles of Sustainable Soil Management in Agroecosystems - page 423

16 Carbon Sink Capacity

and Agronomic
Productivity of Soils of
Semiarid Regions of India

Ch. Srinivasarao, B. Venkateswarlu,
Rattan Lal, A. K. Singh, Sumanta Kundu,
and Vijay Sandeep Jakkula

CONTENTS
16.1 Introduction ................................................................................................ 424
16.2 Soils of Rainfed Regions ............................................................................ 425
16.3 Constraints in Rainfed Production Systems ............................................... 426
16.3.1 Uncertain Rainfall .......................................................................... 426
16.3.2 Degraded Soils ............................................................................... 426
16.3.3 Low-Input Application ................................................................... 426
16.3.4 Biotic Stresses ................................................................................ 428
16.3.5 Untapped Water-Nutrient Synergy ................................................ 429
16.3.6 Poor Crop Management .................................................................. 429
16.3.7 Lack of Focused Extension Program ............................................. 431
16.3.8 Lack of Appropriate Policy Support .............................................. 432
16.4 Yield Gaps in Rainfed Agriculture ............................................................ 432
16.5 Poor Soil Health and Multinutrient Deficiencies ....................................... 434
16.6 Declining NUE: A Serious Concern .......................................................... 437
16.7 Importance of SOC .................................................................................... 437
16.7.1 Carbon Stocks in Different Soil Types of Rainfed
Agroecosystems of India ................................................................ 438
16.7.2 Soil Carbon Stocks in Relation to Production System ...................440
16.7.3 Carbon Stocks in Relation to Rainfall ........................................... 4 41
16.8 Reasons for Soil Carbon Depletion in Rainfed Tropical Systems ............. 443
16.9 Carbon Sequestration .................................................................................444
16.10 Carbon Management Options ....................................................................446
16.10.1 Site-Specific RMPs......................................................................446
16.10.1.1 Improvement of Crop Yield through Gliricidia
Green Leaf Manuring................................................. 447

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