Study finds conservation farm policies reduced global cropland degradation

Government conservation-focused agricultural policies have measurably reduced cropland degradation worldwide over the past two decades, according to a new study published in Nature Food by researchers from the University of Bonn and partner institutions.

The researchers analyzed satellite remote-sensing data covering roughly 83 million cropland condition measurements collected between 2001 and 2019 and linked the findings to a database of approximately 4,700 national agricultural policies. Using two quasi-experimental evaluation approaches — difference in discontinuities and difference in differences — the study concluded that conservation-oriented farm policies improved global cropland condition by an average of 2% to 5%.

The study found wide variation in results between countries, with impacts ranging from minimal gains in some nations to improvements exceeding 20% in others. According to the authors, governance quality and policy funding levels were the strongest factors influencing outcomes, with well-funded programs in countries with stronger institutions consistently producing larger improvements.

Among the policy categories assessed, conservation payment programs and soil and land-use regulations delivered the strongest results. Each additional policy in those categories improved cropland condition by an estimated 0.8 to 0.9 percentage points, marking one of the first global-scale attempts to quantify the causal effects of conservation policies on agricultural land quality rather than relying on correlation-based analysis.

The findings suggest that expanding direct-payment programs for conservation practices such as cover cropping, reduced tillage and buffer strips could provide measurable long-term benefits for soil quality and agricultural productivity. The authors added that scaling up well-designed programs in countries with weaker governance structures could generate significantly larger gains than those currently observed.

Sources: Nature Food, University of Bonn