What’s up this time with QGIS?
In this practical we produced maps on spatial distribution of jobs, one through all industries and four within different selected industries in the capital area. The selected industries were commercial, industrial, scientific and real estate. First, we opened vector data about the job locations in the capital area. The data was in form of 500 x 500 meter grids. In the data there was lots of non-valuable grids which were valued as “-1”. In order to create sensible analysis we converted those “-1”-values to zero with Field calculator and its tool called Conditional statements. Conditional statements -tool is automated find and replace -tool which finds every unwanted value and replace them with preferred one. To be precise, we made find- and replace actions only for columns (industries) we were analysing and created new attribute column for corrected values.
After having our attribute tables ready for map creation we proceeded to make heat maps with default Heat map -tool in QGIS. At first we did a heat map about all of the jobs in Capital area (map below). Settings in the tool were following:
- Output raster: we made a reasonable name for the file
- Radius: 1000 meters
- Cell size: 20 x 20 meters
- Kernel shape: quadric (biweight)
- Use weight from field selected: we selected the sum of jobs
- Output values: raw values
Secondly, we did rest of the maps within the selected industries (commercial as an example below). Settings in the tool were mostly same, only the weighted field varied depending on what industry we were working on.
Finally, we finalized our maps with Map composer adding all the necessities to the maps.
In addition, we did a diagram with MS excel. To do that we needed sufficient data from our vector layer. In order to get what we wanted, which was spatial distribution of jobs in Helsinki, we selected all the the attributes within Helsinki and saved them as own layer using Save selected features -tool. Then we opened our saved file in dbf -format with excel and created a wanted diagram.
In this exercise the phases with QGIS were relatively easy and straightforward, the biggest questions raised again about the things behind operations. What is the Heat map -tool really doing, what all the numbers it produces mean and how to visualize them? It was interesting to notice the uncomfortable feeling when trying to select what to tell in legend.
Analysis of the maps & diagram
The five finished heatmaps provide fantastic visualization of workplace distribution in Helsinki capital region. Each heatmap tells its own story, but they can be roughly separated into two categories: a) both highly local and spread and b) heavily clustered and centered in few locations.
Both industrial and commercial job distribution maps show plenty of activity around Helsinki capital region. With industrial jobs, this probably means factories, logistics centres and office complexes, located in established industrial zones and in proximity of motorways. Industry tends to avoid the pricey land of the city centre (with the exception of Hietalahti dockyard, which I will further examine later).
Commercial jobs are centered in large shopping malls and they too have good connections to motorways. Helsinki city center (which has its own share of shopping centers, too!) is the largest single cluster of commercial activity, but the shopping center of Jumbo in Vantaa doesn’t seem to be far behind. Of the five sectors we compared in this exercise, commercial jobs are most evenly spread. This likely is the result of people’s desire to do their daily shopping close to where they live.
An interesting possibility to continue from this study would be to compare the spatial distribution of commercial and industrial jobs historically, say between 1980 and 2010. In recent decades, many industrial workplaces have disappeared from the Helsinki city centre and relocated to the outskirts of the city (especially by the outer ringroad), that provide good connections and cheaper land. The major exception to me is the Hietalahti dockyard, where they continue to build ice-breakers to this day. Ship-building is one of the few labor-intensive industries remaining within Helsinki borders. Helsinki, hoping to preserve part of its industrial past, supports the dockyard’s operation in its master plan for decades to come.
A different picture emerges from looking at the scientific and real-estate jobs distribution maps (the real-estate industry was our optional choice). These two industries are heavily centralised in the centre of Helsinki and other, very limited areas. The scientific industry hotspots are centered at the university campuses in city centre, Meilahti, Viikki and Otaniemi. Minor activity can be found throughout capital region, probably supported by private sector employers. Many of those companies would probably be attracted to the clusters created by the universities, which makes universities the driving force of the scientific sector in Helsinki region.
Real estate job distribution is also the most active in the city centre, where the land is, of course, dearest. There are many smaller hotspots in local centres such as Herttoniemi, Malmi, Tikkurila and Leppävaara. In that regard, real estate job distribution map is similar to the commercial jobs map. Unlike in that map,one of those minor real-estate hotspots can match the colored carpet of the city centre.
The total job distribution map falls somewhere in between the two categories. It reveals that workplaces exist throughout the capital region. On the other hand, the deep red carpet covering Helsinki city centre show that the activity is heavily centralized. A few otherhotspots in Pitäjänmäki, Keilaniemi, Tikkurila and Helsinki-Vantaa airport complete the picture.
The diagram depicting industry structure by workplaces reveals that Helsinki is a true multi-industry city with no dominant sector of industry. Governance services and hotels and restaurants seem to be the largest sectors, but neither exceeds 1/6 of the total share. Historically, administrative sector has been important for Helsinki as it has never been known as an industrial town. The industry that it had has since relocated to surrounding cities, confirmed by the low share of the sector in the diagram. Those workplaces have been replaced by large scientific and information sectors, for which the university educates a skilled workforce. The relatively large share of international organizations is also worth noting, while it supports Helsinki’s claims of being a multicultural city.
The heatmaps reveal that most industries have clustered or at least have some activity in city centre. According to the maps,Helsinki city centre embodies that multi-industry city depicted in the diagram. The other clusters in the area can be very strong in one industry (such as scientific sector of Otaniemi) but severely lacking in another (for example realestate sector in Otaniemi). The challenge for the future is to duplicate the diverse job structure of the city centre to other districts in the region.