The Millennium Ecosystem Assessment classifies ecosystem services as: Provisioning (food, water, timber, fibre), Regulating (climate regulation, disease control, flood regulation), Cultural (recreational, spiritual, aesthetic), and Supporting (nutrient cycling, soil formation, primary production, crop pollination). Nutrient cycling and crop pollination are Supporting services — they are necessary for producing all other ecosystem services. Food and water = Provisioning. Climate and disease control = Regulating. Maintenance of diversity is not a standard MEA category name.