Impacts of urbanization and climate change on water quantity and quality in the Carp River watershed

Abstract

Pressure on water resources has reached unprecedented levels during the last decades because of climate change, industrialization, and population growth. As a result, vulnerability to inappropriate water availability and/or quality is increasing worldwide. In this paper, a Soil & Water Assessment Tool (SWAT) model of the Carp river watershed located in the city of Ottawa, Ontario was calibrated and validated. The model was then used to evaluate the individual and coupled impacts of urbanization and climate change on water quantity (discharge) and quality (nitrogen and phosphorus loads). While most of the watershed is currently rural, the headwaters will undergo rapid urbanization in the future, and there are concerns about possible negative impacts on water quantity and quality. Seven scenarios were developed to represent various watershed configurations in terms of land use and climate regime. Future climate time series were obtained by statistically downscaling the outputs of nine regional climate models, ran under representative concentration pathways (RCP)4.5 and RCP8.5. The impacts were evaluated at the main outlet and at the outlet of an upstream sub-watershed that would be most affected by urbanization. Results show that climate change and urbanization's impacts vary greatly depending on the spatial scale and geographic location. Globally, the annual average discharge will increase between 6.75 and 9.34% by 2050, while changes in annual average nitrogen and phosphorus loads will vary between −1.20 and 24.84%, and 19.15 and 23.81%, respectively. Local impacts in sub-watersheds undergoing rapid urbanization would be often much larger than watershed-scale impacts.

Climate change impacts on the flow regime and water quality indicators using an artificial neural network (ANN): a case study in Saskatchewan, Canada

“…They concluded that variability of the mentioned water quality parameters may change the ecosystem services of the basin, hence, adaptive management may need to be applied in the region. Zango et al (2021) assessed the impacts of urbanization and climate change on the river runoff as well as water nitrogen and phosphorus loads in the Carp Watershed, Ontario, Canada. They concluded that the urbanization and climate change impacts vary substantially depending on the geographic location and spatial scale.…”

Response of runoff and nitrogen loadings to climate and land use changes in the middle Fenhe River basin in Northern China

“…The Soil and Water Assessment Tool (SWAT) is a semi-distributed, physically based hydrological model that can be used to describe surface, root zone, groundwater, and stream processes (Arnold et al 1998). The SWAT model is now widely used in many watersheds throughout the world to study the impact of climate change and land use on runoff (Yang et al 2019;Hajihosseini et al 2020) and water quality (Delia et al 2021;Zango et al 2022). However, its analytical ability in assessing the sensitivity of water quality to climate change and land use is discussed relatively scarcely in the existing studies.…”

Evolution of landscape dynamics in the Yangtze River Delta from 2000 to 2020

“…Landscape patterns are the distribution patterns and composite structures of landscape units in the space in different numbers, types, densities, and configurations (Turner 1990;Hu 2003), which are influenced by both natural and anthropogenic factors, which in turn restrict various ecological processes, thus further influencing the social and economic aspects of the region (Hao et al 2017;Hashem et al 2019). Quantitative studies of landscape patterns often use the landscape pattern index directly related to land use (Alberti 2005), or evaluate the resources and environmental status of the research area (Guiamel & Lee 2020) and forecast the future development (Gao et al 2021;Zango et al 2021) by various kinds of assessment and prediction model. The scope of study includes watersheds (Nuanchan et al 2015;, deserts (Duan et al 2012), wetlands (Gong et al 2011), etc., delimited by ecological scope, as well as provinces and municipalities delimited by administrative or territorial scope, and countries (Zhao et al 2007;Cirelli & Vineri 2014;Burgalassi & Luzzati 2015;Li & Qi 2019).…”