Email RIS file
Bookmark
Report an Issue

Behavior of Duckweed as an Agricultural Amendment : Nitrogen Mineralization, Leaching, and Sorghum Uptake

Author:
Kreider, Andrew
Published:
[University Park, Pennsylvania] : Pennsylvania State University, 2015.
Physical Description:
1 electronic document
Additional Creators:
Brennan, Rachel, Bruns, Mary Ann, Bryant, Ray, and Burgos, William
Access Online

Availability

I Want It
I Want It

Finding items...

Graduate Program:
Restrictions on Access:
Open Access.
Summary:
Excessive nitrogen (N) and phosphorus (P) in surface waters can promote eutrophication (algae-dominated, low oxygen waters) which decreases water quality and aquatic life. Duckweed (Lemna minor), a floating aquatic plant, rapidly absorbs N and P from water and its composition shows strong potential as a soil amendment. Therefore, it may be used to transfer N and P from eutrophic water bodies to agricultural fields. In this work, dried duckweed was incorporated into agricultural soil in microcosm, column, and field tests to evaluate biological nitrogen cycling, nutrient retention, and crop yield compared to compost, diammonium phosphate (DAP), and an amendment-free control. In microcosm tests, 25 ± 13% of duckweed N was mineralized, providing on average less mineral-N than DAP (107 ± 21%), but more than compost (11 ± 12%). In columns, duckweed treatments leached only 2% of the N added, which is less than the 60% of DAP-N that leached. Nearly 4% more phosphate was leached from DAP treatments than from duckweed treatments relative to the control. Duckweed and compost stabilized additional phosphate-P, likely due to their organic carbon content. Crop yield, as well as runoff N and P, were measured in field tests growing forage sorghum (Sorghum bicolor). Although less total N was applied to duckweed plots than to DAP plots (75 kg/ha vs. 130 kg/ha, respectively), duckweed was found to retain 30% more total mineral-N in a tilled agricultural field than DAP, while supporting a comparable yield. These tests indicate that duckweed may provide a sustainable source of N and P.
Other Subject(s):
Genre(s):
Dissertation Note:
M.S. Pennsylvania State University 2015.
Technical Details:
The full text of the dissertation is available as an Adobe Acrobat .pdf file ; Adobe Acrobat Reader required to view the file.
View MARC record | catkey: 16212912