Climate modelNumerical climate models use quantitative methods to simulate the interactions of the important drivers of climate, including atmosphere, oceans, land surface and ice. They are used for a variety of purposes from study of the dynamics of the climate system to projections of future climate. Climate models may also be qualitative (i.e. not numerical) models and also narratives, largely descriptive, of possible futures.
Climate variability and changeClimate variability includes all the variations in the climate that last longer than individual weather events, whereas the term climate change only refers to those variations that persist for a longer period of time, typically decades or more. Climate change may refer to any time in Earth's history, but the term is now commonly used to describe contemporary climate change. Since the Industrial Revolution, the climate has increasingly been affected by human activities.
PolycultureIn agriculture, polyculture is the practice of growing more than one crop species in the same space, at the same time. In doing this, polyculture attempts to mimic the diversity of natural ecosystems. Polyculture is the opposite of monoculture, in which only one plant or animal species is cultivated together. Polyculture can improve control of some pests, weeds, and diseases while reducing the need for pesticides. Intercrops of legumes with non-legumes can increase yields on low-nitrogen soils due to biological nitrogen fixation.
Crop wild relativeA crop wild relative (CWR) is a wild plant closely related to a domesticated plant. It may be a wild ancestor of the domesticated (cultivated) plant or another closely related taxon. The wild relatives of crop plants constitute an increasingly important resource for improving agricultural production and for maintaining sustainable agro-ecosystems. Their natural selection in the wild accumulates a rich set of useful traits that can be introduced into crop plants by crossing.
Dryland farmingDryland farming and dry farming encompass specific agricultural techniques for the non-irrigated cultivation of crops. Dryland farming is associated with drylands, areas characterized by a cool wet season (which charges the soil with virtually all the moisture that the crops will receive prior to harvest) followed by a warm dry season. They are also associated with arid conditions, areas prone to drought and those having scarce water resources.
Nonfood cropA nonfood crop, also known as industrial crop, is a crop grown to produce goods for manufacturing, for example fibre for clothing, rather than food for consumption. Industrial crops is a designation given to an enterprise that attempts to raise farm sector income, and provide economic development activities for rural areas. Industrial crops also attempt to provide products that can be used as substitutes for imports from other nations.
Hybrid regimeA hybrid regime is a type of political system often created as a result of an incomplete democratic transition from an authoritarian regime to a democratic one (or vice versa). Hybrid regimes are categorized as having a combination of autocratic features with democratic ones and can simultaneously hold political repressions and regular elections. Hybrid regimes are commonly found in developing countries with abundant natural resources such as petro-states.
History of plant breedingPlant breeding started with sedentary agriculture, particularly the domestication of the first agricultural plants, a practice which is estimated to date back 9,000 to 11,000 years. Initially, early human farmers selected food plants with particular desirable characteristics and used these as a seed source for subsequent generations, resulting in an accumulation of characteristics over time. In time however, experiments began with deliberate hybridization, the science and understanding of which was greatly enhanced by the work of Gregor Mendel.
