Livelihood is mode of subsistence. Ecosystem functions as a home in which all living things co-exist, including human beings. Ecological livelihood constitutes a fundamental foundation that reflects the cultural behavioral norms of humans in equal and harmonious relationship with other living things in an ecosystem. A society is defined as knowledgeable when its people know how to conduct themselves in a respectful and polite manner in the arms of the compassionate and tolerate ecosystem, so as to listen to, learn from and understand the ecosystem. In other words, in an ethical and knowledgeable society, people respect their surrounding ecosystem – the cradle of bearing and nurturing themselves. Ecological livelihood represents the operational principles of a society in which people express their gratitude towards the ecosystem through their daily interaction with the ecosystem.
Human beings and other living things can live in the ecosystem without any man-made constructions or machines, while all constructions or machines would stop working if they are rejected by the ecosystem. (Tran thi Lanh 2009)