Ключевые слова: abstract, agriculture, alternative, bio, biology, clean, concept, conceptual, conservation, continents, day, development, earth, eco, ecologic, ecological, ecology, ecosystem, energy, environment, environmental, friendly, global, globalization, globe, grass, green, growth, leaf, life, map, natural, nature, organic, planet, plant, pollution, recycle, recycled, recycling, renewable, reuse, save, sign, spring, sustainable, symbol, tree, warming, world,