Impacts of climate change, land management practices and land cover on water resources at the watershed scale
| dc.contributor.advisor | Meng, Fan-Rui | |
| dc.contributor.advisor | Bourque, Charles P.-A | |
| dc.contributor.author | Kang, Xiaoyu | |
| dc.date.accessioned | 2024-10-17T17:56:59Z | |
| dc.date.available | 2024-10-17T17:56:59Z | |
| dc.date.issued | 2024-08 | |
| dc.description.abstract | Water resources are critical to sustaining terrestrial ecosystems and socio-economic systems globally. However, global water supplies are threatened by deforestation and conversion to agricultural lands. Assessing the impacts of landcover change at the watershed scale poses significant challenges. Difficulty arises from inherent variability associated with the interaction of complex land-surface conditions due to variation in watershed characteristics and landuse/landcover, daily-to-annual response of watersheds to changing local-to-regional weather. It also comes with small sample sizes typically obtained with traditional watershed experiments. Consequently, comprehensive, integrated models of watershed hydrology is used in assessing impacts of climate change, land management, and landcover on water resources in watersheds. Hydrological models have their own limitations, as they are developed and refined according to pre-existing knowledge of hydrological processes. In this study, a comprehensive hydrological model (i.e., SWAT) in combination with experimental data and statistical methods was used to assess the impacts of climate change, landuse practices, and landcover variances on water resources at the watershed scale. This hybrid approach overcomes the limitations existing in both field experiments and watershed models. Here, three scientific questions associated with the application of the model are addressed. Climate change is shown to have a negative impact on crop yields under three emission scenarios, Representative Concentration Pathways (RCPs) 2.6, 4.5, and 8.5. Under RCP 8.5, a significant reduction in crop yield is projected to ensue from 2060 to 2099, i.e., 13–23% from historical yields. Present research also indicates the impacts of elevated ambient CO2 concentrations on water yield can be distinguished at watershed level and was shown to be responsible for a 1.6% increase in water yield over 23-year. The gradual, annual application of flow diversion terraces in the same watershed caused a measurable reduction in water yield by about 29% at the end of the study period. It was also found that forested watersheds had lower peak flow during the snowmelt seasons, and this flow was delayed by at least 7–17 days following the peak flow observed in an agricultural watershed. The results from this study have profound implications for water-resource management, landuse planning, and flood-risk management. | |
| dc.description.copyright | © Xiaoyu Kang, 2024 | |
| dc.format.extent | xv, 172 | |
| dc.format.medium | electronic | |
| dc.identifier.uri | https://unbscholar.lib.unb.ca/handle/1882/38162 | |
| dc.language.iso | en | |
| dc.publisher | University of New Brunswick | |
| dc.relation | Province of New Brunswick | |
| dc.relation | Agriculture and Agri-Food Canada | |
| dc.relation | University of New Brunswick - Faculty of Forestry and Environmental Management | |
| dc.relation | Natural Sciences and Engineering Research Council (NSERC) | |
| dc.relation | New Brunswick Environmental Trust Fund (NBETF) | |
| dc.relation | Environment and Climate Change Canada (ECCC) | |
| dc.rights | http://purl.org/coar/access_right/c_abf2 | |
| dc.subject.discipline | Forestry and Environmental Management | |
| dc.title | Impacts of climate change, land management practices and land cover on water resources at the watershed scale | |
| dc.type | doctoral thesis | |
| oaire.license.condition | other | |
| thesis.degree.discipline | Forestry and Environmental Management | |
| thesis.degree.grantor | University of New Brunswick | |
| thesis.degree.level | doctorate | |
| thesis.degree.name | Ph.D. |