EGU24-1004, updated on 08 Mar 2024
https://doi.org/10.5194/egusphere-egu24-1004
EGU General Assembly 2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

Comparative effect of incorporated and surface spread crop residues, poultry manure and their biochars on soil health indicators along a soil profile 

Tanvir Shahzad1, Rummana Basit Mir1, Umme Aiman Fiaz1, Huma Shahid1, Fiza Arshad1, and Muhammad Sanaullah2
Tanvir Shahzad et al.
  • 1Department of Environmental Sciences, Government College University Faisalabad (hereistanvir@gmail.com)
  • 2Institute of Soil and Environmental Sciences, University of Agriculture Faisalabad, Pakistan (sanasial@gmail.com)

Biochar is being touted as a wonderful amendment for improving soil health. However, its effectiveness for alkaline soils that are poor in organic matter has rarely been evaluated, particularly in long term field experiments. We laid down a field experiment based on wheat-maize crop rotation where we either incorporate or spread on surface the residues of the previous crop (wheat or maize), poultry manure or biochar(s) derived from these organic amendments. They are applied at the rate of 2 tons ha-1 before sowing each crop. It was hypothesized that the organic amendments applied in their feedstock or biochar form will considerably differ in space and time vis-à-vis soil health indicators. Moreover, tillage (incorporation i.e., conventional tillage vs surface spreading i.e., no tillage) would significantly alter the effect of these organic amendments. Over two years and four cropping seasons, the CO2-C emissions from the field were significantly higher (12-17%) when residues or biochar were incorporated. However, the feedstocks (residues/manure) induced significantly higher CO2-C emissions than their respective biochars across the tillage treatments (13-23%). Furthermore, the ammonia emissions were significantly reduced when biochars were added (5-11%) where surface spreading, or incorporation didn’t induce any difference. First soil sampling was done till 75 cm in depth increments of 15 cm, after two years of the experiment (Nb: the experiment is running). Microbial biomass (MBC) was significantly higher in upper layers (0-15 cm, 15-30 cm) in the plots incorporated with residues while all other amendments or tillage treatments showed similar MBC. No change in MBC was observed below 30 cm in any treatment. The soil organic carbon content (& stocks) were slightly but significantly higher (by 5-14%) in upper layers where biochars were incorporated, whereas incorporating residues increased soil organic carbon compared to biochar surface spreading. The extracellular enzymatic activity particularly of β-glucosidase, was significantly altered to 60 cm in some treatments with residue addition (incorporation or spreading) inducing higher activity. The leucine aminopeptidase activity remained unchanged throughout the soil profile in most of the treatments. However, chitinase activity was significantly higher in some biochar amended soils. These preliminary results indicate that residues/manure as well as their biochar significantly improve soil health indicators and that their method of application (incorporation vs spreading) significantly alter their effects. However, it must be noted that both types of amendments have improved different soil health indicators at this stage of the experiment.  

How to cite: Shahzad, T., Mir, R. B., Fiaz, U. A., Shahid, H., Arshad, F., and Sanaullah, M.: Comparative effect of incorporated and surface spread crop residues, poultry manure and their biochars on soil health indicators along a soil profile , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1004, https://doi.org/10.5194/egusphere-egu24-1004, 2024.