Salmon in the Klamath River in the United States were once abundant. They no longer are.
Plastic waste has reached catastrophic proportions in the oceans and it is increasing further still.
Compared to coffee, a popular cash crop, avocado is more tolerant of variations in precipitation.
The 7,000sqm rooftop garden at Thammasat University is the largest such green space in Asia.
Termites can be important for ecosystems in semi-arid lands like grasslands and savannahs.
Gold mining or chocolate making? Some indigenous tribes in the Amazon have made their choice.