Sewage
Spring is go time for climbers who hope to summit Mount Everest, Earth’s highest peak above sea level. Hundreds of mountaineers from around the world travel to Asia in April and May, headed for base camps in Nepal and Tibet. But jagged peaks won’t be the only thing they see. Especially on Everest’s more heavily traversed Nepal side, they’ll find fields of garbage – including cans, bottles, plastic and human and animal excrement. Each year, more than 60,000 trekkers and climbers visit the Sagarmatha National Park and Buffer Zone, a high-altitude swath of the Khumbu region in northeast Nepal that includes Everest and seven other peaks. Some 400 to 500 climbers attempt to summit Everest every year. The trash problem first became evident in the 1980s and 1990s, when climbing on the mountain and trekking in Khumbu began to increase. Climber and trekker numbers have further skyrocketed in the past 20 years. Most coverage of this issue focuses on nega...
Rivers are awash with excess nutrients, chemicals, and other pollutants, including sewage. Globally, roughly 50% of wastewater is treated at facilities before being released into nearby bodies of water. But new research shows that even advanced treatment might not be enough to safeguard the health of freshwater ecosystems. Researchers released dilute, treated wastewater into an unpolluted stream in northern Spain and made a before and after comparison of energy flows through the ecosystem. “We found subtle yet fundamental shifts in ecosystem function.” “We found subtle yet fundamental shifts in ecosystem function after adding wastewater,” said Ioar de Guzman, a freshwater ecologist at the University of the Basque Country in Spain and lead author of the study. By manipulating a pristine ecosystem, she and her colleagues could isolate the effects of wastewater, which can be masked in streams that contain other types of...