Soil carbon pools under long-term rice-wheat cropping system in Inceptisols of Indian Himalayas

Comments on the publication entitled “Agropedogenesis: Humankind as the 6th soil-forming factor and attractors of agrogenic soil degradation’’ by Yakov Kuzyakov and Kazem Zamanian in ‘’Biogeosciences Discuss."

“…Such shift in practice is already under way in tropical soils of many agriculturally based countries including Indian sub-continent. Therefore, it will be important to showcase and also to share some soil carbon research accomplished in India following the recommendations of the National Agricultural Research System (NARS), which suggests no sign of soil degradation in terms of agropedogenesis as conceptualized and proposed by Kuzyakov and Zamanian (2019). It is realized that the carbon content in soils changes depending on the land use system and time.…”

“…The National Bureau of Soil Survey and Land Use Planning (NBSS&LUP) of the Indian Council of Agricultural Research (ICAR), through organized research initiatives, sponsored by national and international organizations, has developed datasets of SOC for two important crop production zones, viz. the Indo-Gangetic Plains (IGP) (52.01 M ha, occupied mainly by Entisols, Inceptisols, Alfisols, Mollisols, Vertisols and their intergrades, and the black soil region (BSR) (76.4 M ha, occupied mainly by Vertisols and their intergrades and Alfisols, Pal, 2017) in the semi-arid tropics (SAT) Mandal et al, 2014). The datasets for 1980 and 2005 indicate an overall increase in SOC stock in the Benchmark spots under agriculture, practised for the last 25 years.…”

“…Results of long-term fertilizer experiments with rice-based double or triple cropping systems indicate soil's capacity to store greater C, and maintain higher C in passive pools and that active fraction of soil C can be used as an indicator of soil health. The application of NPK plus FYM emerged as a cost-effective technology for Indian farmers (Pathak et al, 2011;Mandal et al, 2008;, Krishna et al, 2018 because the application of organic amendments builds up the SOC pool which enhances the quality of the soil, ecosystem services of soils, water and combats climate change (Lal, 2011;Christensen et al, 2009). However, management interventions of the NARS have caused depletion of soil organic carbon in some Mollisol of the IGP and they are presently classified as Alfisols having no other form of degradation.…”

“…(a) Soils as a unique natural capital, provide multiple benefits to humans, and are the foundation of agriculture and deliver multiple soil ecosystem services. It is expected that global food production will grow by 50% by the year 2030 and by 100% by the year 2050 in order to fulfil the demands of a growing world population and changing food consumption patterns (Godfray et al, 2010). It is often feared that the current long-term agricultural systems may damage the natural capital.…”

“…It is often feared that the current long-term agricultural systems may damage the natural capital. Therefore, a need is always felt to mitigate the negative effects of agriculture on soils through 'sustainable intensification of agriculture', which would maintain the increasing trend of the current agro-ecosystems by sustaining natural capital stocks and also by minimizing adverse effect on environment (Baulcombe et al, 2009;Godfray et al, 2010;Koch et al, 2013;Lal, 2009). Projections indicate that 80% of crop production growth in developing countries up to 2030 will be derived through intensification (FAO, 2009).…”