The world could forfeit as much as $39 trillion in economic benefits by 2050 if the rapid destruction of wetlands continues, according to a report released Tuesday by the intergovernmental Convention on Wetlands. The study finds that 22% of wetlands—including peatlands, rivers, lakes, mangroves and coral reefs—have disappeared since 1970, marking the fastest loss rate of any ecosystem. Wetlands deliver essential services such as flood regulation, water purification, carbon storage and support for fisheries and agriculture. Their degradation therefore carries large financial, food-security and climate-adaptation costs. The report estimates that 411 million hectares—roughly half a billion football fields—have already been lost, while one-quarter of the remaining wetlands are in a degraded state. Driving forces include land-use change, pollution, agricultural expansion, invasive species and climate-linked pressures such as sea-level rise and drought. “The scale of loss and degradation is beyond what we can afford to ignore,” lead author Hugh Robertson said. To halt and reverse the decline, the Convention on Wetlands calls for annual global investment of $275 billion to $550 billion—far above current spending levels. The findings will shape discussions at the treaty’s triennial meeting, scheduled for 23–31 July in Victoria Falls, Zimbabwe.