Short answer: "Community-based" on this website means "owned by local, grassroots conservation and community development organizations that have their own rainforest reserves and build their own lodges and tourism attractions."
"Regular" ecotourism is any ecotourism business not owned by community organizations.
More background information: During the last 25 years, many Europeans and North Americans have been inspired to buy up large tracts of Costa Rican tropical forest in order to preserve it. They built eco-lodges as a way of supporting their conservation efforts. They knew how to create a relaxed yet elegant atmosphere of tropical chic in gorgeous mountain settings, or where jungle meets beach. They also were well versed in marketing to the US and Europe. These small, principled eco-lodges attracted the attention of travel magazines, and set a high standard for what ecotourism could be. The lodge owners, usually expats, often had enlightened employment policies and provided training and education for local people, as well as other benefits. So the residents in pristine rural areas saw that ecotourism was a good thing.
This development coincided with a massive sell-off of Costa Rican land to foreigners, so that now 90% of beach territory is owned by non-Costa Ricans. As Costa Rica became famous as an ecotourism destination, larger, more commercial beach hotels and condos were also built, often without any regard to the lack of infrastructure regarding water supply, sewage, solid waste disposal, etc., etc., etc. We witnessed all these problems as we were doing our sustainable tourism rating survey. So responsible ecotourism and unprincipled, exploitative tourism were developing at the same time.
Meanwhile, in traditional farming and fishing communities like La Fortuna near Arenal Volcano, Puerto Viejo and Cahuita on the Atlantic coast, Tamarindo on the Pacific, local people would sell their farms to interested foreigners and often use the money to build simple cabins, in order to get in on the tourism boom. Often farmers did not realize what a fickle industry tourism is, and so would end up without their farms and with only seasonal income from their cabins. They did not have the marketing expertise, the capital, nor the sense of tropical elegance that foreign lodge owners had. Sleepy fishing villages would suddenly sprout forests of signs announcing these cabins and those cabins, late-night bars and discos would open, drugs and crime would rear their ugly heads, and suddenly the traditional way of life had disappeared.
In the frenzy to find new sources of income from tourism, there were few efforts by local residents to band together and address what was being lost. One notable effort was by ATEC, the Talamancan Association for Ecotourism and Conservation founded in the mid-1980s, which still exists in Puerto Viejo de Talamanca today.
So the isolated farming and fishing communities that were funded by the UN Development Program to have their own ecotourism businesses were a way of helping communities confront the challenges brought by tourism.
I hope that the community control of these projects and their relative isolation will help them be able to pick and choose what they want from tourism, while letting it supplement their farming incomes. Family farms get very little support on this planet.
In many of the projects highlighted on this website, organic agriculture, appropriate energy technology, and preservation of forests and rivers are combined with tourism in a way that holds great promise for the future. By visiting these communities, you will be inspired by their ability to put innovative principles into practice. You will also see the results of the intelligent, dedicated work of the Small Grants Program of the Global Environmental Facility, COOPRENA, ACTUAR and other NGO's who, in a time of worldwide chaos, are faithfully sowing the seeds of peace.