Uploaded on 2015-11-10 by Talana

> Blockquote The city of Johannesburg contains over 10 million trees and is often referred to as an urban forest. The intra-urban spatial variability of the levels of vegetation across Johannesburg’s residential regions has an influence on the urban heat island effect within the city. Residential areas with high levels of vegetation benefit from cooling due to evapo-transpirative processes and thus exhibit weaker heat island effects; while their impoverished counterparts are not so fortunate. The urban heat island effect describes a phenomenon where some urban areas exhibit temperatures that are warmer than that of surrounding areas. The factors influencing the urban heat island effect include the high density of people and buildings and low levels of vegetative cover within populated urban areas. Johannesburg is spread out and has many residential suburbs and distributed business centres. Johannesburg also contains over 10 million trees and is therefore referred to as an urban forest. Studies have shown vegetation to have a mitigating effect on the UHI. However not all parts of Johannesburg contain high levels of vegetation. Areas which are most deficient in vegetation are the city’s urban centres, such as Sandton and Randburg, and informal settlements. ![Green City][1] ![Surrounded by Heat Islands][2] ![Reflective][3] 3. Increased urbanisation with lack of housing stock, led to the development of informal settlements. Deforestation & contamination of streams & rivers are some of the direct consequences of these unplanned events. Since rapid & increased urbanisation is a fact in especially the African continent, my suggestion would be to incorporate the allocation of land for informal settlements, with the provision of services (sanitation, water, energy etc). The building materials are mostly & generally corrugated iron panels - extremely hot in summer & extremely cold in winter. Along with this is the use of coal and wood for energy, exacerbating the problems of air quality & deforestation, fires, sanitation among some. Provision of appropriate (not brick and mortar) materials and services are a minimum in order to control & mitigate effect of uncontrolled & organic settlements. ![Informal Settlements - Unplanned Consequences][4] 4. Policy Yes policies in place with mitigating strategies in spatial development framework plans http://www.jhbcityparks.com/index.php/what-we-do-contents-31/major-projects-contents-58/joburg2040 [The city that's a rain forest][5] [1]: http://www.jhbcityparks.com/images/stories/parks/greencity.jpg [2]: https://placesjournal.org/assets/legacy/media/slideshows/tang-watkins-3.jpg [3]: https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcQy8WUQzBPzT5KuRsVq67gKxHj6nFMCMhPhd_9Hi4IA85dZOfn1 [4]: http://wet-africa.co.za/WET/wp-content/uploads/2014/08/2005_0825aug050010.jpg [5]: http://www.jhbcityparks.com/index.php/street-trees-contents-29