In this edition of eco@africa, we visit Nigeria were small farmers are dealing with increasing challenges in the face of climate change. One radio station, the Smallholders Farmers Rural Radio, is trying to help them with its daily agricultural programming. The station broadcasts everything from environmental farming techniques to business advice and daily market information.

A green oasis springs up in the Egyptian desert. Is it a mirage? In this case, no - it's one of many forests growing in an otherwise sandy arid landscape thanks to a little ingenuity from German and Egyptian scientists - and some reprocessed sewage.

We also go to Kenya, where the battle to save a tree containing properties that help fight illnesses like prostate cancer is underway. And we look to South Africa, where this week's Eco Hero is working to protect the endangered African penguin.

We find out how one town in northern England has become a veritable outdoor buffet for inhabitants and how a German brewery is brewing beer and saving energy at the same time.

Have you ever wondered why our oceans are becoming acidic and what the consequences are for marine life and us? We give you the lowdown. It's not to be missed.