Timing and duration of access mat use impacts their mitigation of compaction effects from industrial traffic

• Published in: Journal of environmental management 2022-02, Vol.303, p.114263-114263, Article 114263
• Main Authors: Thompson, Karen A., James, Kassia S., Carlyle, Cameron N., Quideau, Sylvie, Bork, Edward W.
• Format: Article
• Language: English
• Subjects: Dry mixedgrass prairie; Energy infrastructure development; Grassland; Heavy equipment; Nitrogen; Nutrient supply; Penetration resistance; Plants; Seasons; Soil; Water; Water infiltration
• ISSN: 0301-4797; 1095-8630
• DOI: 10.1016/j.jenvman.2021.114263

Grasslands are declining worldwide and are often impacted by industrial activities, including infrastructure development. Current best management practices for low-disturbance development on grasslands include the use of wooden access mats as temporary work platforms and roadways to mitigate soil compaction and rutting due to heavy traffic. We assessed the impacts of heavy traffic (TON), and the impacts of the same heavy equipment driven over top of access mats (AM), on soil physical, hydrological, and nutrient responses in sandy and loamy soils in the Dry Mixedgrass prairies over a 2-year period. We also assessed how the timing (early vs. late in the growing season) and duration (6 vs. 12 vs. 24 weeks) of AM and TON affected the same metrics. Compared to undisturbed soils, TON increased soil penetration resistance (15 cm depth) up to 93% in loamy and up to 101% in sandy soils, and decreased water infiltration rates from 53 to 71%, respectively. Notably, the negative impacts of TON on soil physical characteristics and hydrology were larger in sandy vs. loamy soils, and when moist soils were exposed to traffic early in the growing season. AMs were effective at mitigating soil compaction from industrial traffic when used on sandy soils. However, AM use increased the supply of total nitrogen and other plant macro- and micro-nutrients, particularly in soils subject to longer (12–24 wk) mat placement. Results indicate TON may have long-lasting effects on grassland (particularly sandy) soils, and that AM use represents an effective tool to mitigate traffic impacts. Further, early-season traffic should be avoided when soils are moist (whether with AM or not), and AMs should be placed on soils for limited durations (≤6 wk) to minimize potential nutrient losses. •Direct wheeled traffic compacted soil and reduced infiltration in grassland soils.•Traffic early in the growing season has negative long-lasting impacts on soils.•Access mats mitigated compaction from traffic, particularly in sandy soils.•Increased nutrient supply under access mats may impact grassland recovery.•Access mats used for short (≤6 wk) periods mitigate traffic impacts on soil.