Dear Abir Dey,

Calcareous soil contains organic and inorganic carbon (C) pools, which both contribute to CO2 emission during closed-jar incubation. The mineralization of organic C and dissolution of inorganic C are both related to soil moisture, but the exact effect of water content on CO2 emission from calcareous soil is unclear. The objective of this experiment was to determine the effect of soil water content (air-dried, 30%, 70%, and 100% water-holding capacity (WHC)), carbonate type (CaCO3 or MgCO3), and carbonate amount (0.0, 1.0%, and 2.0%) on CO2 emission from calcareous soil during closed-jar incubation. Soil CO2 emission increased significantly as the water content increased to 70% WHC, regardless of whether or not the soil was amended with carbonates. Soil CO2 emission remained the same or increased slowly as the soil water content increased from 70% WHC to 100% WHC. When the water content was ≤30% WHC, soil CO2 emission from soil amended with 1.0% inorganic C was greater than that from unamended soil. When the soil water content was 70% or 100% WHC, CO2 emission from CaCO3 amended soil was greater than that from the control. Furthermore, CO2 emission from soil amended with 2.0% CaCO3 was greater than that from soil amended with 1.0% CaCO3. Soil CO2 emission was higher in the MgCO3 amended soil than from the unamended soil. Soil CO2 emission decreased as the MgCO3 content increased. Cumulative CO2 emission was 3–6 times higher from MgCO3 amended soil than from CaCO3 amended soil. There was significant interaction effect between soil moisture and carbonates on CO2 emission. Soil moisture plays an important role in CO2 emission from calcareous soil because it affects both biotic and abiotic processes during the closed-jar incubation.

Please find attached herewith tillage & Calcareous soil Consevation articles,

Regards

Prem Baboo

https://www.researchgate.net/post/Short-and_long-term_consequences_of_zero_minimum_tillage_on_crops_productivity_and_soil_environment?_tpcectx=profile_answers

Data Effect of Additional Carbonates on CO2 Emission from Calcare...

Article Effect of Additional Carbonates on CO2 Emission from Calcare...

Dear Abir,

you can find some old papers in the related topics at SSSAJ, which are mostly subscription based. However I feel this area is relatively unexplored in recent times especially in Indian calcareous soils. Couple of book chapters etc is available to gain the basic knowledge but research papers are very few. I can refer you one paper; Caravaca & Albaladejo (1999) at Geoderma, though which is based in cultivated & forest soils of Spain (Attached in inbox). If I find something more, I will send.

Regards,

Debarati

Abir , very relevant to calcareous soils.  Soils in the  tropics, especially those in the drier regions have low reserves of organic matter and plant nutrients. The soil carbon (C) pool composed of soil organic C and soil inorganic C is not only critical for the soil to perform its productivity and environmental functions, but also plays an important role in the global C cycle. The sequestration of atmospheric C in the soil and biomass not only reduces greenhouse effect but also helps maintain or restore the capacity of the soil to perform its production and environmental functions on a sustainable basis. Thus, there is a great interest in research on sequestration of atmospheric C into the soils for maintaining or restoring soil fertility and mitigating carbon dioxide emissions to the atmosphere1. (PDF enclosed )

In such soils , rice intensification followed by wheat intensification has proved very handy  with regard to expending the carbon sink capacity (PDF enclosed ). But , it remains to be still seen , to what an extent conservation agriculture could increase the soil carbon stock , especially in developing world  of dryland areas growing staple crops in small size farms, contrary to effectiveness mechanized farming in big size farms.(PDF enclosed).  

http://www.iisc.ernet.in/~currsci/sep102000/655.pdf

Thank you sir/madam ...the answers are very helpful