<p></p><p></p><p>Land use alteration and
climate change are major contributors to the hydrological cycle within
watersheds. They can influence the quantity and quality of water resources, the
ecosystem and environmental sustainability. Urban areas have expanded in recent
decades, accompanied by a noticeable increase in energy and water use. Such
changes in land use have many implications for humans to meet the increasing
share of the planet’s resources and water issues. Hence, distinguishing the
effects of land use change from concurrent climate variability is a particular
challenge for studies on operational management processes. In this work, some shortcomings related to climate
variability and land use change have been addressed, as applied to land surface
temperature (LST) and groundwater resources. Thus, the main goal
of this study is to evaluate the impacts of land use change on surface
temperature and the impact of urbanization and climate variation on hydrology. The research methodology included modeling
approaches that were used to estimate the land surface temperature and the
responses of hydrology to climate change and urbanization.</p>
<p>Land use maps
derived from Landsat datasets were analyzed using several classification
techniques to evaluate the intensity and pattern of urbanization and land
surface temperature in the Greater Cairo Region (GCR), Egypt. Accuracy of Landsat derived land use data were relatively
high and up to 96.5%. Findings indicated that the GCR land use alteration was
dynamic and that vegetation loss was the main contributor to urban expansion in
the GCR. Consequently, this led to increased LST and modified urban microclimate.
The results showed that vegetation cover decreased by 7.73% within a 26-year
timespan (1990-2016).</p>
<p>Land use alteration impacted
not only land surface temperature, but also, combined with variation in
climate, affected watershed hydrology, specifically streamflow and baseflow. Changes in streamflow and filtered baseflow in three
watersheds: Little Eagle Creek (LEC), Upper West Branch DuPage
River (UWBDR) and Walzem Creek watershed, from 1980
to 2017, caused by climate alteration and land use change were separated and
accessed using the SWAT (Soil and Water Assessment Tool) model.
Results showed that SWAT performed well in capturing the streamflow and
baseflow in urban catchments. SWAT model calibration and
validation was within acceptable levels for streamflow and baseflow. About 30%, 30% and 12% of the LEC, UWBDR and
Walzem Creek watershed areas changed from agricultural to urban areas. Findings
for the LEC watershed indicated that the variability in the baseflow and
streamflow appeared to be heavily driven by the response to climate change in
comparison to the variability due to altered land use. The contribution of both
land use alteration and climate variability on the flow variation was higher in
the UWBDR watershed. In Walzem Creek, the alteration in streamflow and baseflow
appeared to be driven by the effect of climate variability more than that of urbanization.</p>
<p>Finally, the impacts
of basin lithology and physical properties on baseflow were examined using
multiple regression models. Results suggest that the
baseflow index (BFI) can be predicted using the basin’s physical and geological
characteristics. This included different land uses and climate variables with
high accuracy and low relative errors. BFI was found to be highly driven by
precipitation and fractional areas of different lithologies in the basins in
various regions. These could be estimated with a high accuracy, as opposed to evapotranspiration that caused lower
model accuracy.</p>
<p>Information gleaned from these
outputs can help in understanding the dynamics of land use change and climate
variation, in order to help policy-makers predict and plan for future expansion
in developing countries and across the globe, in achieving long-term
sustainability of soil and water resources and their impact on climate change.
Increasing efforts to prevent further urbanization and vegetation loss should
be regarded as a practical management strategy and are of vital significance to
many communities. In addition, the regression models developed in this study
can be easily exploited in other areas with poor hydrological data quality and
ungauged sites in order to estimate the amount of groundwater discharge.</p><p></p><p></p>
| Identifer | oai:union.ndltd.org:purdue.edu/oai:figshare.com:article/12159183 |
| Date | 24 April 2020 |
| Creators | Mohamed Atef Moham Aboelnour (8736174) |
| Source Sets | Purdue University |
| Detected Language | English |
| Type | Text, Thesis |
| Rights | CC BY 4.0 |
| Relation | https://figshare.com/articles/Assessment_of_land_use_urbanization_impacts_om_surface_temperature_and_hydrology/12159183 |
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