Daycent is a daily time series

biogeochemical Biogeochemistry is the scientific discipline that involves the study of the chemical, physical, geological, and biological processes and reactions that govern the composition of the natural environment (including the biosphere, the cryosphere, th ...

model A model is an informative representation of an object, person or system. The term originally denoted the plans of a building in late 16th-century English, and derived via French and Italian ultimately from Latin ''modulus'', a measure. Models c ...

used in

agroecosystems Agroecosystems are the ecosystems supporting the food production systems in our farms and gardens. As the name implies, at the core of an agroecosystem lies the human activity of agriculture. As such they are the basic unit of study in Agroecology, ...

to simulate fluxes of

carbon Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon mak ...

and

nitrogen Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...

between the atmosphere,

vegetation Vegetation is an assemblage of plant species and the ground cover they provide. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic characte ...

, and

soil Soil, also commonly referred to as earth or dirt Dirt is an unclean matter, especially when in contact with a person's clothes, skin, or possessions. In such cases, they are said to become dirty. Common types of dirt include: * Debri ...

. It is a daily version of th
CENTURY
biogeochemical model. The

United States Environmental Protection Agency The Environmental Protection Agency (EPA) is an independent executive agency of the United States federal government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it ...

United States Department of Agriculture The United States Department of Agriculture (USDA) is the federal executive department responsible for developing and executing federal laws related to farming, forestry, rural economic development, and food. It aims to meet the needs of com ...

/ARS and the Colorado State University Natural Resource Ecology Lab are currently using the Daycent model to develop a national inventory of N₂O emissions from

U.S. The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

agricultural soils. This inventory will be compared and contrasted with the existing Intergovernmental Panel on Climate Change (IPCC) agricultural N₂O emissions inventory for the United States. Having more accurate data to account for

nutrient cycling A nutrient cycle (or ecological recycling) is the movement and exchange of inorganic and organic matter back into the production of matter. Energy flow is a unidirectional and noncyclic pathway, whereas the movement of mineral nutrients is cycli ...

could have significant implications for public policy associated with the

United Nations Framework Convention on Climate Change The United Nations Framework Convention on Climate Change (UNFCCC) established an international environmental treaty to combat "dangerous human interference with the climate system", in part by stabilizing greenhouse gas concentrations in ...

(UNFCCC) and potential future

mitigation Mitigation is the reduction of something harmful or the reduction of its harmful effects. It may refer to measures taken to reduce the harmful effects of hazards that remain ''in potentia'', or to manage harmful incidents that have already occur ...

efforts in the United States. Model inputs include daily maximum/minimum air

temperature Temperature is a physical quantity that expresses quantitatively the perceptions of hotness and coldness. Temperature is measurement, measured with a thermometer. Thermometers are calibrated in various Conversion of units of temperature, temp ...

and

precipitation In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls under gravitational pull from clouds. The main forms of precipitation include drizzle, rain, sleet, snow, ice pellets, graupel and hail. ...

, surface

soil texture Soil texture is a classification instrument used both in the field and laboratory to determine soil classes based on their physical texture. Soil texture can be determined using qualitative methods such as texture by feel, and quantitative methods ...

class, and land cover/

use Use may refer to: * Use (law), an obligation on a person to whom property has been conveyed * Use (liturgy), a special form of Roman Catholic ritual adopted for use in a particular diocese * Use–mention distinction, the distinction between using ...

data. Model outputs include daily fluxes of various N-gas species (e.g., N₂O, NO_x, N₂); daily CO₂ flux from heterotrophic soil respiration; soil organic C and N; net primary productivity; daily water and nitrate (NO₃) leaching, and other

ecosystem An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the syste ...

parameters. Daycent has been tested with data from various native and managed systems. In similar studies, comparisons between Daycent simulated data and measured values for annual crop yields, N₂O emissions, and NO₃ leaching produced r² values of 0.72, 0.68, and 0.61 respectively.Del Grosso, Stephen, "Daycent Model Estimates of Greenhouse Gas Mitigation Potential of Cropped Soils in the USA." Session No. 70 U.S. Agriculture’s Role in Soil Carbon Sequestration and Greenhouse Gas Mitigation (GRACEnet) George R. Brown Convention Center: General Assembly Theater Hall C 1:30 PM-5:30 PM, Tuesday, 7 October 2008 Other models used for simulating carbon and nitrogen biogeochemistry in agricultural systems include
DNDC

EPIC

References

External links

* {{DEFAULTSORT:Daycent Agriculture Agronomy Agriculture and the environment Systems ecology