Open AccessInteractions of Soluble and Solid Organic Amendments with Priming Effects Induced by Glucose
Author(s) -
Thangarajan Ramya,
Chowdhury Saikat,
Kunhikrishnan Anitha,
Bolan Nanthi
Publication year - 2014
Publication title -
vadose zone journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.036
H-Index - 81
ISSN - 1539-1663
DOI - 10.2136/vzj2014.01.0002
Subject(s) - dissolved organic carbon , soil water , environmental chemistry , organic matter , biosolids , compost , chemistry , manure , effluent , soil organic matter , wastewater , environmental science , agronomy , environmental engineering , soil science , biology , organic chemistry
In this work, the effects of various dissolved organic matter (DOM) sources (piggery effluent [PigE], dairy effluent [DE], sewage effluent [SE], and stormwater [SW]) on the priming effect (PE) of soil C as affected by solid organic amendments (biochar [BC], biosolids [BS], compost, and poultry manure [PM]) and microbial activity were quantified using landfill, arable, and metal‐contaminated field and spiked soils. The BC‐amended soil caused significantly lower PEs than BS‐, compost‐, or PM‐amended field soils due to its low DOM. A strong positive correlation was observed between the dissolved organic C content and glucose‐induced PE of soil C. However, a negative correlation between the PE and dissolved N in different sources of DOM suggested that the PE may also be influenced by the quality of added C sources in the soils. The DE‐treated soil with the highest dissolved N resulted in significantly lower PE than PigE‐, SE‐, and SW‐treated soils. Compared with the uncontaminated soils, microbial activity as CO 2 evolution and PE decreased markedly in the metal‐contaminated soils, which may be attributed to the heavy metal toxicity. However, the distinct increase in microbial activity in the wastewater‐treated contaminated soils suggests the capacity of wastewater to reduce metal toxicity in soils. The findings of this study suggest that although wastewater DOM may reduce the toxic effect to microorganisms, it can have an important effect on the source of CO 2 by stimulating the decomposition of native soil organic matter.