National-scale changes in crop diversity through the Anthropocene

Area of Science:

• Agricultural Science
• Ecology
• Environmental Science

Background:

• Crop expansion beyond domestication centers is a hallmark of the Anthropocene, altering agricultural biodiversity.
• Global-scale analyses of crop diversity changes exist, but national-scale patterns, drivers, and consequences are less understood.

Purpose of the Study:

• To quantify changes in country-level crop richness and evenness from 1961 to 2017.
• To explore the biogeographical patterns of crop diversity in the Anthropocene at national scales.

Main Methods:

• Utilized production data for 339 crops across over 150 countries (1961-2017).
• Quantified country-level changes in crop richness (number of crops) and crop evenness (distribution of crop production).

Main Results:

• Nearly all countries showed increased crop richness, with a distinct global rise beginning in the early 1980s.
• Crop evenness increased in only half of the countries, indicating varied diversity dynamics.
• While crop richness increased universally, crop evenness showed opposing trends, and cropland homogenization was modest.

Conclusions:

• Ubiquitous increases in crop richness are a key biogeographical feature of the Anthropocene.
• National-scale assessments are crucial for understanding how crop diversity changes impact agricultural resilience to environmental shifts.