Effect of Long-Term Organic Cropping Systems on Physico-Chemical Properties of the Soils of Indian Punjab

Organic farming is gaining momentum because of awareness among consumers for quality food. The long term effects of organic cropping systems on soil quality yet not have been studies in details. Therefore the present study the long term effect of five cropping systems viz. Poplar (Populus deltoids) + turmeric (Curcuma longa), sugarcane (Saccharum officinarum Linn )+ bottle gourd (Lagenaria siceraria) - broccoli (Brassica oleracea), basmati rice (Oryza sativa) - wheat (Triticum aestivum), sugarcane fodder and maize (Zea mays) + summer moong (Vigna radiate) - wheat on soil physico-chemical properties was studied at Bhagat Puran Singh Natural Agriculture Farm and Research Centre, Amritsar, Punjab (31.5730 N, 75.0660 E). The depth wise soil samples from these cropping systems were collected after rabi (2018-19) and kharif (2019) seasons. Poplar + turmeric cropping system has significantly higher soil organic carbon(SOC), soil carbon stock(SOCS), soil aggregate associated carbon(AAC), water stable soil aggregates (WSA) and mean weight diameter(MWD) of soil than other cropping systems. Sugarcane fodder cropping system has significantly higher soil pH than other cropping systems while basmati rice - wheat cropping system has significantly lower electrical conductivity (EC) and higher soil bulk density (BD) compared to other cropping systems. In the top soil (0-7.5 and 7.5-15 cm depths) SOC, SOCS, AAS, EC, WSA and MWD were significantly higher than subsurface layers (15-22.5 cm and 22.5-30 cm depth) whereas soil pH and BD were significantly lower in surface soil than subsurface soil.