Category : Uncategorized
As settlements, industries and other city infrastructure expand into the landscape to settle and connect swelling numbers of urban dwellers, natural ecosystems continuously recoil together with the services they provide. Kampala City, the 13th fastest growing city on the planet best embodies this classical phenomena. From 1989 to 2010, corresponding with explosive population growth, the area of developed land within the city increased from 27% to 78%. Noteworthy, this development occurs at the expense of the natural assets that built areas replace and affects the capacity of ecosystems to provide their attendant services. However, there are natural vegetation patches that survive this wave of degradation and such enclaves referred to herein as remnant patches inspired a probe by a team of three researchers led by Urban Action Lab’s Professor Shuaib Lwasa. This investigation set out to examine why cities’ remnant patches remain after their parent ecosystems have been degraded and to provide clues on how long and strong these patches can stand the same destructive forces that created them. To provide insights into these two questions, a combination of remote sensing, GIS and surveys were conducted. High resolution mosaic of satellite images were classified and attributed using spatialized data from ground truthing exercises. Patch attributes such as closeness, connectivity, neighbouring landuse, biodiversity rank, ecosystem services change, and status were probed in a GIS environment. Such investigation provided answers and clues as to why and how some patches survive the same destructive processes that eroded parent ecosystems. Further analyses and interpretation of field surveys gave glimpses of the capacity of the city’s remnant patches to withstand future degradation forces. Findings indicated that patches that were connected or close to similar patches had significantly higher chances of withstanding destruction as compared to those that were distant from and/or not connected to similar patches. Patches that were protected by fencing or natural buffers also were at a low risk of being converted. Patch neighbouring landuses such as settlements and construction sites posed serious threats to patches than neighbours like beaches and recreation centres. This inquiry established that patch attributes such as connectivity, closeness, and neighbouring landuse were key indicators of patch dynamics such as resilience, a parameter that is increasingly becoming important in modern cities. Most importantly however, this investigation provided novel blueprints for city planners and conservationists which if replicated/mimicked on new or vulnerable patches could be a final frontier in conserving cities’ fast disappearing biodiversity.
By Benon B Nabaasa Shuaib Lwasa Enock Ssekuubwa