Effects of agricultural practices on microtopography in restored prairies

Abstract

Tallgrass prairies are often restored from agricultural fields that have long since removed the natural microtopography. Therefore, our study investigates how these restored prairies recover microtopography. We used precise elevation data collected from LiDAR to compare differences in microtopography between crop fields, fallow fields, newer restored prairies (restored within the last 10 years), and older restored prairies (restored 10 to 20 years ago). We also compared plant biodiversity indices between newer and older restored prairies using nested plot vegetation sampling. Our first research question is how microtopography differs between the sites. Our results show that older restored prairies had the most microtopographic variation, followed by newly restored prairies. Our second research question is how plant biodiversity correlates with microtopographic variation. Our results show that older restored prairies had the highest biodiversity and the highest microtopographic variation. Our third research question is how microtopographic variation changes between 2011 LiDAR data to the 2021 LiDAR data. Our results show an increase in microtopographic variation after a decade once farming has ceased. Synthesis and application: Land managers that have better access to LiDAR data may want to add microtopographic variation as a tool for long-term monitoring ecosystem function in restored tallgrass prairie sites. Our study suggests that microtopographic features appear to increase with the age of a restoration site, providing a visual way to show a restoration’s success.