Ameliorating effects of designer biochars in a hard-setting subsoil layer: soil fertility and plant biomass

Authors: Sigua, Gilbert; Novak, Jeffrey; Watts, Donald - Don; Myers, William - Tillman; JOHNSON, MARK - Environmental Protection Agency (EPA)

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 3/30/2018
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Soils in the southeastern U.S. Coastal Plain region have meager soil fertility and frequently have compacted subsoil layers (E horizon). Designer biochar has gained global interest as an amendment to improve the fertility, chemical, and physical properties of degraded agricultural soils. We hypothesized that addition of different designer biochars in Norfolk soils with hard setting subsoil layer will have variable effects on soil fertility, biomass and nutrient uptake of winter wheat. Five different designer biochars were evaluated to improve soil fertility and enhance plant biomass and nutrient uptake in soils with hard-setting subsoil layer. Biochars were produced by pyrolysis at 500 centigrade (C) from pine chips (Pinus taeda), poultry litter (Gallus dometicus) feedstock, hardwood, and as blends (50:50 and 80:20) of pine chip (PC): poultry litter (PL). Our results supported our hypothesis that addition of different designer biochars had variable effects on soil fertility, biomass and nutrient uptake of winter wheat. Higher nutrient availability was found after additions of biochars especially applications of 100 percent (%) PL and 50:50 blend of PC and PL. On the average, applications of 100% PL and 50:50 blend of PC:PL had the greatest amount of soil total nitrogen with means of 1.94% and 1.44%, respectively. When compared with the control, 50:50 blend of PC:PL additions resulted in increase of 669% for P, 830% for K, 307% for Ca and 687% for Mg while application of 100% PL increased the concentration of extractable P, K, Ca, and Mg by 363%, 1349%, 152% and 363%, respectively. Our study also demonstrated the favorable and beneficial effects of different designer biochars on biomass productivity and nutrient uptake of winter wheat grown in Norfolk soils with hard setting subsoil layer. Application of 80:20 blends of PC and PL was found to be superior over other blends with the exception of PL because of its favorable effects on biomass productivity and nutrient uptake of winter wheat. Overall, our results showed promising significance for improving soil fertility and tilth of hard setting subsoil layer since biochars did improve the aboveground, belowground and total biomass of winter wheat.