=Paper=
{{Paper
|id=Vol-2323/SKI-Canada-2019-7-1-4
|storemode=property
|title=A GIS-based Model of Ecosystem Services for the Northeast Swale in Saskatoon, Saskatchewan
|pdfUrl=https://ceur-ws.org/Vol-2323/SKI-Canada-2019-7-1-4.pdf
|volume=Vol-2323
|authors=Rong Shen,Honghao Yu,Bram Noble,Weiping Zeng,Sarina Gersher,Thang Phung,Cherie Westbrook,Kenneth Belcher,Farzana Nijhum,Abigail Weger,Robert Alary,Sarah Rutley,Scott Bell
}}
==A GIS-based Model of Ecosystem Services for the Northeast Swale in Saskatoon, Saskatchewan==
https://ceur-ws.org/Vol-2323/SKI-Canada-2019-7-1-4.pdf
Spatial Knowledge and Information Canada, 2019, 7(1), 4
A GIS-based model of ecosystem services
for the Northeast Swale in Saskatoon,
Saskatchewan
RONG SHEN1, HONGHAO YU1, BRAM NOBLE2, WEIPING ZENG1, SARINA GERSHER3, THANG
PHUNG1, CHERIE WESTBROOK2, KENNETH BELCHER4, FARZANA NIJHUM2, ABIGAIL WEGER2,
ROBERT ALARY5, SARAH RUTLEY5, SCOTT BELL2
1The Spatial Initiative, wez948@mail.usask.ca,
2Department of Geography and Planning, b.noble@usask.ca,
3City of Saskatoon,
4Department of Bioresource Policy, Business and Economics, ken.belcher@usask.ca,
5University Library
University of Saskatchewan, Canada
will shrink and further impact the Swale
ABSTRACT (Gersher, 2015)
Protecting natural places on urban fringes The overall goal of this project is to develop
requires tools that are dynamic, easy to and apply an ecosystem services-based
update, and support analysis. A Web GIS regional strategic environmental assessment
system was produced to develop an (RSEA) framework to evaluate baselines
ecosystem services-based framework for the and assess potential risks of future
Northeast Swale, a natural protected area in conservation and development scenarios for
Saskatoon, Saskatchewan. Data were the Swale. Ecosystem services (ES) are the
integrated in a user-friendly Web GIS benefits that society obtains from healthy
system to identify ecosystem services and and functioning ecosystems (ChapinIII,
their values. The building of the tool and its 2013), including food provision, flood
connection with the spatial data of the control, and cultural benefits (D.S.Ojima,
ecosystem are discussed. 2013). To make informed decisions about
the protection of ES, City planners,
1. Introduction conservation authorities and land
developers need baseline information about
ES, the importance of those services, and an
The Northeast Swale (hereafter the Swale) is
a natural protected area in the northeast of understanding of how different choices
the city of Saskatoon, Saskatchewan. The about land development affect ES. The
Swale provides important ecological, evaluation of ES is thus essential to
environmental, and cultural benefits (City of assessing, planning for, and understanding
Saskatoon, 2018), but is under increasing the impacts of lade use decisions (Kenneth J.
pressure from the cumulative impacts of Bagstad, 2012). A major challenge, however,
human activity and urban land use. is that current land use planning processes,
Disturbances in this area have caused a particularly urban land use plans, rarely
decrease in species diversity and an increase integrate futures-based strategic
of invasive species. The planning and future assessments of ‘what if’ scenarios.
development of adjacent residential
GIS is increasingly used to support the
neighborhoods is an enduring threat, that
evaluation of ES, as it can emphasize the
2 A GIS-based model of ecosystem services for the Northeast Swale in Saskatoon
spatial relationships between land use and prairie uplands and a series of wetlands.
human activities (R.S.de Groot, 2010). GIS The Swale is home to hundreds of species,
also helps to present the complexity of including federally-identified species of
current and future land use scenarios that concern. The Swale is also subject to the
urban areas are facing (Philip Stessens, cumulative stress of a growing city,
2017). In previous studies (Austin Troy, including residential development, storm
2006), GIS technology has also been linked water drainage, and an approved commuter
as a tool to value ES, using a transfer parkway.
method with spatial analysis. With the
development of Internet technology, Web
GIS has been widely used. Compared with
traditional GIS, Web GIS allows multiple
users to access maps and supporting data,
and to effectively manage resources, which
can increase the flexibility and reliability of
GIS applications for ES valuations and
assessments (Su Tianyun, 2008).
In this paper we develop a Web GIS
platform to visualize existing ES provided
by the Swale, and to identify future
conservation and development pressures.
The sections that follow describe the Figure 1. Study area.
development of the Web GIS tool to connect
spatial information with ES. The online 2.2 Data
maps developed integrate important
features, such as disturbed areas, rare Five categories of data were employed: (1)
species observation locations, and cultural the study area delineation, (2) development
heritage sites. Landscape scanning shows and conservation (land use polygons, road
changes in the Swale landscape over half a construction current and future),
century. Three scenarios, baseline, no neighborhood areas, trails, and target
growth, and fully development, are then management areas, (3) ecological
shown to depict possible future pressures to environments (rare species observation
ES services in the Swale under different locations, habitat area, wetland area, and
levels of development and conservation. vegetation-type polygons), (4) cultural
heritage (historical highlights data were
The results from this work will serve as gathered, such as the pinned rock, Moose
input to a participatory Web-based survey Woods Batoche Trail), and (5) alternative
of city residents, using a choice experiment scenarios of land uses. Shapefile features
design, to assess future scenarios and derive are shared with the Meewasin Valley
ES values. In this paper, we focus on the Authority (MVA) - – a conservation agency
Web GIS platform. created under the provincial Meewasin
Valley Authority Act for the management of
2. Study Area, Data and Methods lands in the South Saskatchewan River
Valley, including Saskatoon’s Northeast
2.1 Study area Swale.
Aerial photographs showing changes in the
The study area for this project is in the
landscape were provided by the University
northeast region of the City of Saskatoon,
of Saskatchewan Library, the National Air
Saskatchewan (Figure 1). The Swale is a 26-
Photo Library, and Natural Resources
kilometer-long corridor that links native
Canada. Photographs from year 1956 and
A GIS-based model of ecosystem services for the Northeast Swale in Saskatoon 3
year 1977 were processed. Landsat satellite provided the basis for all map scales.
level-2 imagery was downloaded from the Photographs
USGS website and was used to represent the
landscape in 1988, 1998, 2008, and 2018.
Airborne Lidar imagery was collected from
the City of Saskatoon to analyze surface were processed in Esri ArcGIS software.
features. Aerial photographs from 1960 and 1972
were geo-referenced for use in the online
2.3 Methods map. Airborne Lidar imagery was collected
for 2017 with 67 tiles covering the Swale
A Web GIS was developed to present a region. Data for full feature cloud points and
baseline Swale map. Geospatial data were bare earth points were explored.
gathered and uploaded into the Web GIS
server so users can view them in a Web The 67 tiles covering the Swale region were
browser or other electronic device with assembled in a mosaic with 1 m spatial
Internet access. Web GIS is a data resolution and 0.05 m vertical accuracy in
management tool that allows users to Esri ArcGIS software to generate the raster
choose specific targets and easily turn data layers of the digital elevation model (DEM)
layers on and off (Ningning Kong, 2014). and the digital terrain model (DTM). The
Web GIS supports multiple data sources DEM was from the bare earth point clouds,
such as HTML and JavaScript so that and the DTM was from the full feature point
designers meet client and user requirements clouds. Then the imagery was put into the
(Yu Nakayama, 2017). ArcScene to show the different elevations of
the surface features.
Figure 2 illustrates the Web GIS model.
Shapefiles were input into ArcMap for
spatial analysis. Maps were generated with
selected styles, saved as .mxd files, stored in
a Microsoft SQL Server, then published
using ArcGIS API for JavaScript.
Aerial photographs of Saskatoon taken in
different years were mosaiced and
georeferenced. We used the City of
Saskatoon road map as the reference for
mosaic image registration; this also
Figure 2. Web-GIS model.
4 A GIS-based model of ecosystem services for the Northeast Swale in Saskatoon
3. Results
The Web GIS system can be accessed at
https://gis1test.usask.ca/swale/. The user
interface is shown in Figure 3.
Figure 3. Northeast Swale online map interface.
The website is designed in a user-friendly
way. A drop down menu can be found on
the top right corner of the web page, where
functionalities are grouped in 7 categories,
namely study area, distributed versus
developed, species, culture heritage,
Landsat images 1988-2018, lidar DTM and
alternative scenarios. Layers under each Figure 4. Hotspot map for rare species locations.
category can be turned on or off.
3.2 Development and conservation
3D viewer option allows users to see
landscape changes in elevation. Common The Swale is a protected habitat surrounded
GIS functionalities such as zoom, compass, by agricultural and urban land use. The area
default map view is also available through adjacent to the Swale has been disturbed,
the quick buttons located on the top-left potentially by factors that influence the
corner. Furthermore, changes in rare balance between ecosystem and social
species from year 1900 to 2017 can also be activities. The MVA has conducted targeted
accessed on the bottom of the web page; the conservation grazing and prescribed
changes during all those years can burning to control invasive plant species, as
automatically be played in a forward time- shown in Figure 5. Such actions maintain
order image sequence. and improve the ecosystem balance.
3.1 Ecological environment
The Swale is covered by native vegetation
and rare plant species, thanks to the efforts
of conservation management. It holds over
200 plant varieties, 100 species of birds,
and other species such as hares, foxes,
coyotes, and deer (Watchers, 2018). Rare
species have been observed all over the
Swale, mostly around wetlands. A higher
accumulation of rare species is found in the
Swale than in other areas of Saskatoon
Figure 5. Map of prescribed burning and targeted
(Figure 4). conservation grazing in the Swale.
A GIS-based model of ecosystem services for the Northeast Swale in Saskatoon 5
3.3 Cultural heritage supports active transportation, stormwater
management and conservation of sensitive
Figure 6 shows important historical sites in areas (Gersher, 2015). Among these three
the Swale that should be protected. Such communities, only Aspen Ridge has a
sites have high educational value to greenway.
Saskatoon citizens.
Figure 6. Cultural heritage sites in the Swale. Figure 7. Baseline shows the existed development around
the Swale.
A 3D animation tour along the Moose
Woods Batoche trail tells the story of this Compared with the “baseline” condition, a
historical site and rare species in the Swale “no growth” scenario only adds future
(https://gis1test.usask.ca/swale/trail/). planned roads. As shown in Figure 8, the
northern part of the Saskatoon Freeway
3.4 Alternative scenarios (dark red line) is a planned future highway.
This category shows three scenarios of the
Swale’s “future”, which will be used in a
choice experiment survey to gather
resident’s values of ES and impacts to ES.
Figure 7 represents the current development
level around the Swale. Urban
infrastructure (roads, residential)
development potentially or directly affects
this area. Three major roads go through the
Swale. The North Commuter Parkway
passes across the Swale and cuts the small
southwest edge of the swale off from the Figure 8 shows a provincial highway is in the future
main Swale. Range Road 3050 cuts through construction plan.
the middle of the Swale. Trails are currently
only in the southwest of the Swale, In Figure 9, future potential neighborhoods
providing limited public access. Existing and trails are added. On the north of the
neighborhoods around the Swale are Swale, University Heights 3 will be
Silverspring and Evergreen, which are fully developed, resulting in the Swale being
developed. Aspen Ridge is currently under surround by residential area. Also, in the
development. A greenway was built to full development scenario, the density of
separate the ecological area and residential trails increases (i.e. access), which provides
area, which includes an ecological buffer, more education and recreation area, but
trail zone and transition zone. The greenway may also bring additional disturbances to
the natural landscape.
6 A GIS-based model of ecosystem services for the Northeast Swale in Saskatoon
4. Conclusion
The Northeast Swale has significant
ecological and historical value for
Saskatoon. This Web GIS platform provides
non-technical users access to technical
maps. By visiting the website on a laptop or
a mobile device, users can easily review ES
features around the Swale and customize
the maps to discover their interests. Public
users can also learn about existing,
emerging, and future development
Figure 9. Full development shows the potential future for pressures and potential. The visualization of
the Swale. ES and potential threats can raise people’s
Urban development stress, including awareness, which could further influence
increased access, invasives, and storm water their willingness to become involved in
runoff/management, may adversely affect public issues, influence the way they use
the ecological environment of the Swale and natural areas, and their willingness to
how residents value the Swale’s ES. financially support their conservation. For
professionals (e.g. city planners), land
3.5 Other information developers, and government, the platform
provides a common and transparent
The online map scanning function allows for baseline to explore, plan for, and value ES in
comparison of 1988, 1998, 2008, and 2018 land use zonation, permitting and decision
(Figure 10). Urbanization can be observed making.
throughout these years. In 1988, the land
Although conservation management is
south of the Swale was covered by native
being conducted, the Swale continues to
grassland. Now, it is residential. In the
face pressures from adjacent urban
future, when the neighborhood north of the
development. Citizen education and
Swale is developed, the Swale will become a
informed management are needed to
grassland “oasis” surrounded by urban
maintain a balance between human activity
areas.
and a healthy ecosystem. This means that
the values placed on ES have a significant
role to play. If, for example, the ecological
buffer around the Swale increases, wildlife
in the Swale could be less affected by human
activity; however, the required revenue (i.e.
residential property tax base) for developing
and maintaining such a buffer zone may
increase. Similarly, more trails would
provide greater public access to the Swale,
which is good for education and recreational
benefit; however, increased access may
result in adverse effects to some ecosystem
services (e.g. habitat), or a decrease in the
value placed on other ES (e.g. natural view-
Figure 10. Online map scanning function shows difference scape).
of landscape around the Swale in 1988 and 2018.
The next stage of our work will involve a
survey of residents adjacent to the Swale, to
A GIS-based model of ecosystem services for the Northeast Swale in Saskatoon 7
assess ES derived from the swale, their Ecosystems. In Vulnerability of
willingness to pay to protect those services, Ecosystems to Climate.
and how the ES values may change under Gersher, E. A. (2015). Meewasin Northeast
the different scenarios of conservation and Swale Master Plan. Saskatoon.
development pressures. The results will be Kenneth J. Bagstad, D. S. (2012). Ecosystem
of value to targeting education programs, Services Valuation to Support
informing land use zoning, and establishing Decisionmaking on Public Lands—A
funding programs to ensure ES protection. Case Study of the San Pedro River
Watershed, Arizona. Reston: U.S.
Acknowledgements Geological Survey.
Ningning Kong, T. Z. (2014). Evaluation of
We thank Environment and Climate Change web GIS functionality in academic
Canada (Environmental Damages Fund) libraries. Elsevier, 1.
(Project 1000-41-0044) for funding this Philip Stessens, A. Z. (2017). Analysing
research project. The authors also thank urban green space accessibility and
The Spatial Initiative and the Social quality: A GIS-based model as
Sciences Research Laboratories (SSRL) at spatial decision support for urban
the University of Saskatchewan for ecosystem services in Brussels.
providing funding and technical support for Ecosystem Services, 328-340.
this project. R.S.de Groot, R. L. (2010). Challenges in
integrating the concept of ecosystem
6. References services and values in landscape
planning, management and decision
Austin Troy, M. A. (2006). Mapping making. Ecological Complexity,
ecosystem services: Practical 260-272.
challenges and opportunities in Su Tianyun, L. B. (2008). A Yellow Sea
linking GIS and value transfer. Large Marine Ecosystem Data
Ecological Economics, 435-449. Sharing System Based on WebGIS
ChapinIII, F. (2013, November 2). Overview Technology. Advances in Marine
of Ecosystem Functions and Science.
Services: Their Importance and Watchers, N. S. (2018). The Northeast
Vulnerability. In Vulnerability of Swale. Retrieved from Swale
Ecosystems to Climate. Retrieved watchers:
from Wikipedia: https://www.swalewatchers.org/abo
https://en.wikipedia.org/wiki/Ecosy ut.html
stem_services Yu Nakayama, K. N. (2017). A Web GIS
D.S.Ojima, T. K. (2013). Social–Ecological Framework for Participatory Sensing
Vulnerability of Grassland Service: An Open Source-Based
Implementation. Geosciences.