With rising sea levels, higher carbon dioxide levels and plastic bottles glutting landfills and oceans, the issue of sustainability has become a hot topic. Hotels and resorts have started to act by ramping up efforts to reduce or eliminate completely their resource and energy consumption.

“If big hotels can make small changes, the ripple can be huge,” said Paula Vlamings, chief executive of Tourism Cares, a nonprofit that works with travel operators to mitigate tourism’s environmental impact. “Sustainability is more than energy conservation or recycling; it is about sustaining communities for the tourism product.”

While Marriott International and other large chains have promised to eliminate items that never fully decompose, like plastic straws, there is still a lot more work to be done.

“There are thousands of these one-at-a-time initiatives, but these are not evenly spread across the lodging industry,” said Bjorn Hanson, a clinical professor at New York University’s Tisch Center for Hospitality and Tourism.