Over 50 % of the world's population live in urban areas, a proportion that is expected to increase to 66 % by 2050. UN Sustainable Development Goal 11 addresses this situation and emphasises the need to make cities and human settlements inclusive, safe, resilient, and sustainable.
An ever-increasing number of cities are proposing sustainable initiatives that provide pragmatic and lasting solutions to these challenges, for example Portland's "20-minute neighbourhoods" or Jakarta's "car-free Sundays". These innovative projects seek to make the lives of their citizens more sustainable.
Another original proposal promoting healthy urban living can be found in the Dutch city of Utrecht: covering the roofs of bus stop with plants to provide a haven for bees and butterflies in the city centre. Aside from giving this street furniture a facelift, the project also aims to increase the bee population and improve air quality for its citizens.
Planted on the roofs of these bus stop are low-growing succulents called sedum, which are a magnet for bees and other pollinating insects. In the Netherlands, as in many parts of the world, the bee population has declined considerably over the past two decades. Many other insects that carry out a vital role in seed dispersal and plant reproduction are in danger of extinction. Adding greenery that serves as a habitat for these species can't fully address the problem of decline in bee population, but it can help to achieve greater urban biodiversity.
According to the Food and Agriculture Organization (FAO) of the United Nations, there are 100 crop species that provide 90 % of the world's food and the vast majority of these are pollinated by bees. However, the population of these insects has fallen sharply due to pesticide use, air pollution and many of the consequences of climate change. What would happen if bees disappeared? The disappearance of bees would spark a food crisis and a global disaster that would threaten the survival of many plant and animal species, including that of humans.
For now, thanks to this sustainable initiative, the roofs of 316 bus stops have been turned into small gardens that require very little upkeep, while a further 96 stops have had solar panels installed instead. As well as providing honeybees with a habitat in which they can thrive and pollinate, the bus stops offer other benefits for the city: They help clean Utrecht's air by trapping fine dust particles and capturing CO₂ from the atmosphere, thereby reducing its concentration in the air.
More cities standing up for bees
However, Utrecht's initiative to tackle the decline in bee population is not the first of its kind. Four years ago, a "bee highway" was created in the Norwegian city of Oslo. The route crosses the city from east to west and stretches over 9 miles (15 km), with resting and feeding points for bees around every 800 feet (250 metres).
Meanwhile, the London Borough of Brent planted a seven-mile (11 km) long "bee corridor" a few months ago, using wildflowers that attract pollinating insects.
C40 Cities, leading the adaptation to climate change
Some of the world's major cities are taking smart steps to adapt to climate change, leading the way toward a more sustainable future and serving as an inspiration for other similar cities. This is called the C40 group, which aims to reduce its carbon emissions and implement sustainable initiatives to limit global warming to 1.5ºC, in line with the most ambitious objectives of the Paris Agreement. It is crucial that cities join the fight against the climate crisis: local initiatives can achieve global effects.