Long-term effects of organic manure and inorganic fertilization on biological soil quality indicators of soybean-wheat rotation in the Indian mid-Himalaya uri icon

abstract

  • A field experiment was accompanied to scrutinize the effect of long-term (21-year) mineral and organic manure fertilizer treatments on carbon mineralization, glomalin related soil protein and some microbial characteristics of arable soils in Indian mid-Himalaya. The experiment was initiated in 1995 includes six treatments: Control, N 120, NPK, FYM, N + FYM and NPK + FYM. Long-term chemical fertilization has been reported to negative effects on soil biological properties, however, the impact of combined use of organic and inorganic fertilization on soil biological properties and its relationship remains poorly understood. Results showed that integrated use of organic and inorganic (NPK + FYM) for 21 years significantly increased in carbon mineralization, easily extractable glomalin related soil protein (EEGRSP) and total glomalin related soil protein (TGRSP). Soil microbial indices (microbial quotient: qMIC, microbial metabolic quotient: qCO(2) and metabolic potential: MP) were enhanced in the NPK + FYM treatment as compared to rest of the treatments. The activities of seven enzymes, viz. dehydrogenase (DHA), beta-glucosidase (beta-GA), invertase (IA), acid phosphatase (Acid-PA), alkaline phosphatase (Alkaline-PA), arylsulphatase (ASA) and urease activity (UA) were significantly influenced by the application of NPK + FYM as compared rest of treatments. Soil fertilization with NPK and FYM was significantly higher fluorescein diacetate assay (FDA) activity as compared to other treatments. Soil microbial properties had strong positive correlation with qMIC, microbial biomass carbon (MBC) and soil organic carbon (SOC), while qCO(2) had negative correlation under both soil layers. Results showed that the 21-year fertilization experiment clearly indicated that NPK + FYM embodied the best management practice (BMPs) for soil biological sustainability and for sustainable food production.

publication date

  • 2021
  • 2021