A measure of growth, reproduction, or yield of a biological system at any scale, together with the services provided. This includes primary production (the rate or extent to which new organic matter is created, usually through photosynthesis); secondary production (the rate or extent to which consumers multiply and grow); related concepts such as standing stock, biomass density, available biomass, trophic transfer, and sustainable yield; and services including not only provisioning of food but also the many other services that are enhanced by high biomass of specific organisms. Distributions include spatial records of chlorophyll concentration; growth rates or biomass of flora or fauna; trophic transfer; human consumption; flood control; or other services, derived through direct measurement, measurement of proxies, or models. Assessments can estimate, model, value, or monetize the ecological or service benefits and impacts of various forms or quantities of primary production or evaluate the effects of nutrients, shading, climate change, or other stressors on production and related services. Predictions are the results of models or projections of future distributions, values, or impacts, including anticipated changes produced by natural and human processes. Predictive models can also evaluate the ecosystem-level effects and impacts to ecological functions or services resulting from changing levels and shifting forms of primary or secondary production; scenario-testing models can compare the production or service outcomes of different management actions, including altering nutrient inputs, harvesting, or other actions.