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ARS Home » Plains Area » Lincoln, Nebraska » Agroecosystem Management Research » Research » Publications at this Location » Publication #395833
Research Project: Evaluating Management Strategies to Increase Agroecosystem Productivity, Resilience, and Viability

Location: Agroecosystem Management Research

Title: Synergistic use of optical and biophysical traits to assess Bromus inermis pasture performance and quality under different management strategies in Eastern Nebraska, US

Author
item MAZIS, ANASTASIOS - University Of Nebraska
item AWADA, TALA - University Of Nebraska
item ERICKSON, GALEN - University Of Nebraska
item Wienhold, Brian
item Jin, Virginia
item Schmer, Marty
item SUYKER, ANDY - University Of Nebraska
item ZHOU, YUZHEN - University Of Nebraska
item HILLER, JEREMY - University Of Nebraska

Submitted to: Agriculture, Ecosystems and Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/16/2023
Publication Date: 2/22/2023
Citation: Mazis, A., Awada, T., Erickson, G., Wienhold, B.J., Jin, V.L., Schmer, M.R., Suyker, A., Zhou, Y., Hiller, J. 2023. Synergistic use of optical and biophysical traits to assess Bromus inermis pasture performance and quality under different management strategies in Eastern Nebraska, US. Agriculture, Ecosystems and Environment. 348. Article 108400. https://doi.org/10.1016/j.agee.2023.108400.
DOI: https://doi.org/10.1016/j.agee.2023.108400

Interpretive Summary: Decreasing nitrogen (N) fertilizer use in grazing systems can minimize environmental impact. In managed pastures, supplementing N as dry distiller grains plus solubles (DDGS) in cattle feed could be used as an alternative to fertilizing with synthetic N. Here, we tested the effects of different fertilization strategies on smooth brome forage performance at a long-term (15-years) study. We evaluated forage performance using direct plant measures as well as using hand-held vegetation sensors. We found that: (1) smooth brome supplemented with DDGS performs efficiently as an alternative to N fertilization; (2) rotational grazing had a positive impact on the vegetation compared to non-grazing; and (3) forage sensor measurements could be used to assess pasture health.

Technical Abstract: We investigated the synergic use of optical and biophysical traits to characterize Bromus inermis (smooth bromegrass) pasture lands and assess the combined effects of long-term (15-years) rotational grazing and management strategies of (i) no fertilization (C), (ii) mineral nitrogen (N) fertilization (HF), and (iii) supplemented fertilization through dry distiller grains plus soluble (DDGS; SF)- on forage growth, performance, and quality. We found that fertilization improved pasture’s biomass, specific leaf area, leaf area index (LAI), as well as forage quality. The use of N fertilization did not offer an advantage (e.g. feed quality, yield) over DDGS under both grazed and ungrazed conditions. Optical, proximal sensing techniques allowed the characterization of pasture lands in a non-invasive and time-efficient manner. We tested established vegetation indices (VIs) for their accuracy in identifying and quantifying important physiological and morphological traits. Results showed that the Normalized Difference Vegetation Index (NDVI) and Vogelmann (VOG) were among the best performing indices. Results contribute to our understanding of the impact of long-term fertilization management on Bromus inermis pastures and validate the use of proximal sensing methods. Proximal sensing methods provide direct, non-invasive, and time efficient tool for assessment of the performance and health of vegetation, keys to successful integrative management strategies.