The Harz Mountains once divided East and West Germany, but today there's a popular national park there. Where barbed wire once stood, a primeval forest is growing. Now climate change is posing serious challenges.

In South Africa, blockchain pioneers developed a crypto platform that allows users to trade unique electronic artworks. Part of the price is donated to conservation projects, which help save endangered animals.

Norway's Arctic coast is plagued by animal invaders: king crabs. While the delicacy is a source of ready money for fishermen, environmental activists fear for the coastal ecosystem as a whole.

Urbanization is growing rapidly across the world. Towns and cities are increasingly vulnerable to extreme weather caused by climate change. But trees and plants can help reduce the risks.

Ethiopia is leading east Africa with its waste management efforts. In 2018, the country transformed its Koshe dumpsite into a waste-to-energy plant that even uses the incinerators' ashes to make bricks.

Tanzania's biggest city, Dar es Salaam, suffers from big traffic problems — but a bus rapid transit system plans to get residents moving again. Current buses are also being phased out for more eco-friendly vehicles.

Around the world record temperatures are being recorded. This is especially obvious in big cities, which have become regular "heat islands." Now a researcher shows us how to ventilate a city.

Cape TowCape Town is upgrading its wastewater treatment plants, most of which were built in the 1950s. The changes will improve the health of citizens — especially those in informal settlements and townships.

Biodiversity is key to healthy surroundings and a better life for all living things. But keeping a balanced environment is essential, says Jean-Paul Ghogue, a freshwater plants specialist for central Africa.

Blue crabs are a serious menace to many other animals in the Mediterranean. Declining fish stocks are a problem for fishermen in Tunisia. Now, some have taken to catching and selling the crabs instead.