The MANAGE database: nutrient load and site characteristic updates and runoff concentration data

Area of Science:

• Environmental Science
• Agricultural Science
• Water Quality

Background:

• The "Measured Annual Nutrient loads from AGricultural Environments" (MANAGE) database compiles site characteristics and nutrient export data.
• Previous versions focused on nutrient load data from the 1980s.
• The database supports research on agricultural nutrient runoff.

Purpose of the Study:

• To update and expand the MANAGE database with recent nutrient data.
• To include nitrogen (N) and phosphorus (P) concentration data alongside load data.
• To provide a comprehensive resource for studying agricultural nutrient export.

Main Methods:

• Incorporated N and P load data from 15 new agricultural runoff studies.
• Added N and P concentration data for all 55 included studies.
• Consolidated data from 1677 watershed years across diverse agricultural land uses.

Main Results:

• The database now includes 1677 watershed years of data for various agricultural land uses.
• Average annual runoff loads were 14.2 kg/ha for total N and 2.2 kg/ha for total P.
• Nutrient losses averaged 10-25% of applied fertilizer N and 4-9% of applied fertilizer P.

Conclusions:

• The updated MANAGE database is a valuable resource for modeling and decision-making related to agricultural runoff.
• It contains data from a majority of published N and P export studies on homogeneous agricultural land uses in the USA.
• Regional, crop-specific analyses are recommended for regulatory and programmatic decisions.