Population densityPopulation density (in agriculture: standing stock or plant density) is a measurement of population per unit land area. It is mostly applied to humans, but sometimes to other living organisms too. It is a key geographical term. In simple terms, population density refers to the number of people living in an area per square kilometre, or other unit of land area. Population density is population divided by total land area, sometimes including seas and oceans, as appropriate.
FuelA fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work. The concept was originally applied solely to those materials capable of releasing chemical energy but has since also been applied to other sources of heat energy, such as nuclear energy (via nuclear fission and nuclear fusion). The heat energy released by reactions of fuels can be converted into mechanical energy via a heat engine.
TransdisciplinarityTransdisciplinarity connotes a research strategy that crosses many disciplinary boundaries to create a holistic approach. It applies to research efforts focused on problems that cross the boundaries of two or more disciplines, such as research on effective information systems for biomedical research (see bioinformatics), and can refer to concepts or methods that were originally developed by one discipline, but are now used by several others, such as ethnography, a field research method originally developed in anthropology but now widely used by other disciplines.
Post-industrial societyIn sociology, the post-industrial society is the stage of society's development when the service sector generates more wealth than the manufacturing sector of the economy. The term was originated by Alain Touraine and is closely related to similar sociological theoretical concepts such as post-Fordism, information society, knowledge economy, post-industrial economy, liquid modernity, and network society. They all can be used in economics or social science disciplines as a general theoretical backdrop in research design.
Sustainable fisheryA conventional idea of a sustainable fishery is that it is one that is harvested at a sustainable rate, where the fish population does not decline over time because of fishing practices. Sustainability in fisheries combines theoretical disciplines, such as the population dynamics of fisheries, with practical strategies, such as avoiding overfishing through techniques such as individual fishing quotas, curtailing destructive and illegal fishing practices by lobbying for appropriate law and policy, setting up protected areas, restoring collapsed fisheries, incorporating all externalities involved in harvesting marine ecosystems into fishery economics, educating stakeholders and the wider public, and developing independent certification programs.
Hunter-gathererA traditional hunter-gatherer or forager is a human living an ancestrally derived lifestyle in which most or all food is obtained by foraging, that is, by gathering food from local naturally occurring sources, especially edible wild plants but also insects, fungi, honey, bird eggs, or anything safe to eat, and/or by hunting game (pursuing and/or trapping and killing wild animals, including catching fish). This is a common practice among most omnivores.
Agrarian societyAn agrarian society, or agricultural society, is any community whose economy is based on producing and maintaining crops and farmland. Another way to define an agrarian society is by seeing how much of a nation's total production is in agriculture. In an agrarian society, cultivating the land is the primary source of wealth. Such a society may acknowledge other means of livelihood and work habits but stresses the importance of agriculture and farming.
