INVESTIGATION OF NITROGEN STATUS IN NOVA SCOTIA VINEYARDS UTILIZING CONVENIENT AND EFFECTIVE TOOLS
| dc.contributor.author | Bangwei, Zhang | |
| dc.contributor.copyright-release | Not Applicable | |
| dc.contributor.degree | Doctor of Philosophy | |
| dc.contributor.department | Department of Plant, Food and Environmental Sciences | |
| dc.contributor.ethics-approval | Not Applicable | |
| dc.contributor.external-examiner | Cornelis (Kees) van Leeuwen | |
| dc.contributor.manuscripts | Not Applicable | |
| dc.contributor.thesis-reader | Andrew M. Hammermeister | |
| dc.contributor.thesis-reader | Gordon W. Price | |
| dc.contributor.thesis-reader | Keith D. Fuller | |
| dc.contributor.thesis-supervisor | David L. Burton | |
| dc.date.accessioned | 2024-11-29T15:41:32Z | |
| dc.date.available | 2024-11-29T15:41:32Z | |
| dc.date.defence | 2024-11-14 | |
| dc.date.issued | 2024-11-27 | |
| dc.description | Effective nitrogen management is critical to a vineyard, yet systematic knowledge of vineyard soil N status is lacking. This project aimed at systematically investigating the N status of Nova Scotia vineyards, including N supply, dynamics, and budgets, and to validate the effectiveness of the parameters, biological N availability and N exposure (NE), as tools for predicting and monitoring soil N supply (SNS). We investigated soil N status in NS vineyards, the responses of soil and vine N status to site effect and slope position, and different N application rates. We investigated N mineralization over the growing season (GSN) in vineyards across NS. The N in the sand-sized fraction played a more important role in stabilizing the organic N pool, while N in the micro-fraction was closely associated with the labile N pool. The latter had a greater impact on GSN. Furthermore, the labile N fraction was more affected by the location in the vineyard and the soil depth than the stable N fraction. Our study examined the spatial distribution differences of soil N in vineyards, revealing that site affects GSN and SMN retention through variations in organic matter (OM) accumulation. Our study proposed and established a relationship between traditional soil sampling method and an ion exchange membrane (IEM) method in terms of long-term (months) and short-term (daily) period, offering a scientific basis for evaluating SMN using IEM technology in viticulture. Additionally, by a comprehensive analysis of the N status of vineyard soil and vines, we established a relationship between soil N status, represented by NE, and plant N uptake, yield, and berry quality. Our study revealed that N fertilizer significantly increased N supply post application, boosting growth of the vines, but not significantly affecting berry yield or quality. The was little accumulation of fertilizer N (<10%) in the grapes at harvest and N use efficiency ranged between 26 and 35% based on N content of the berries. Less than 3% of the fertilizer N remained as SMN at harvest, with 60% unaccounted for. The study emphasize that applying N fertilizer annually in the spring may not always be necessary and should not be universally recommended. | |
| dc.description.abstract | Effective nitrogen management is crucial for vineyards, yet systematic knowledge of vineyard soil nitrogen status is lacking. This project systematically investigated the N status of Nova Scotia vineyards, including N supply, dynamics, and budgets. We validated the effectiveness of biological N availability and N exposure as tools for predicting and monitoring soil N supply. Our research examined soil N status, the responses of soil and vine N to site effects, slope positions, and varying N application rates. Findings showed that N in the sand-sized fraction significantly stabilizes the organic N pool, while N in the micro-fraction is closely associated with the labile N pool. We discovered that site variations affect GSN and SMN retention through differences in organic matter accumulation. Additionally, N fertilizer applications significantly increased N supply post-application, boosting vine growth without notably affecting berry yield or quality. | |
| dc.identifier.uri | https://hdl.handle.net/10222/84707 | |
| dc.language.iso | en | |
| dc.subject | viticulture | |
| dc.subject | soil | |
| dc.subject | nitrogen | |
| dc.title | INVESTIGATION OF NITROGEN STATUS IN NOVA SCOTIA VINEYARDS UTILIZING CONVENIENT AND EFFECTIVE TOOLS |