Identifying pathways to mitigate the negative impact of urbanization trends on croplands

University Of Nebraska-Lincoln, Lincoln NE

Investigators

Abstract

The United States (U.S.) and China accounted for 40 percent of the global increase in urban area during the past three decades. Through this process, urbanization has appropriated millions of hectares of cropland. The overall objective of this project is to identify pathways to reconcile urban growth with crop production, while minimizing negative environmental footprint. The central hypothesis is that current trajectories in urbanization are fostering cropland expansion into less-productive marginal environments and promoting unsustainable crop yield gains on existing cropland, both leading to higher negative environmental impact. Specific aims are to (i) quantify long-term trends in converted land (that was previously cropland and has changed to urban use) and new cropland (due to expansion of cropland on acres not previously used for crops) for key staple crops in U.S. and China, (ii) estimate potential productivity and environmental footprint associated with converted and new cropland for each crop, and (iii) explore future scenarios of land-use change, crop production, and environmental impact for different trajectories of urbanization, intensification, and climate change. To accomplish these aims, remote sensing data will be used to investigate spatio-temporal trends in urbanization and associated changes in planted area for key staple crops in the U.S. and China, coupled with crop modeling and climate and soil datasets to estimate the potential productivity and environmental footprint of the converted and new cropland. The research will provide an assessment of urbanization impact on area and production of key staple crops in each country and evaluate pathways to reconcile urban growth with crop production via better land-use planning and sustainable crop intensification in a context of changing climate and increasing food demand. Through an approach that combines use of remote sensing, crop modeling, and spatial analysis, the project will contribute in-depth understanding of current crop-specific dynamics in cropland conversion for urban uses and the productivity and environmental footprint associated with the converted and new cropland. It will also provide insights on the available room to mitigate these impacts via sustainable crop intensification on existing cropland. Findings from this study will serve as a foundation for future regional studies assessing interactions between urbanization, food production, and environmental impact. From a broader perspective, the research will increase the scientific knowledge for regional modeling of agro-ecosystems and improve current capability to inform land-use policy and prioritize agricultural research and development programs for more sustainable urban-rural interactions. U.S. and Chinese researchers with diverse racial and gender backgrounds will work under the umbrella of this project. Several dissemination activities will be conducted to communicate the research findings to the public, aiming to increase societal awareness about urban expansion and the concomitant need to protect croplands, which, ultimately, can help the U.S., China, and the rest of the world meet the goal of improving food security and economic development while protecting natural resources. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.