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Biology subjects

Curran, M. F.

Publications and source records attributed to Curran, M. F..

2 recordsLinked to original sources

Soil stockpile age does not impact vegetation establishment in a cold, arid natural gas field

Land reclamation is critical to ensure surface disturbance associated with natural gas development is not permanent. Soil management is critical to reclamation success, especially in environments which are challenged by aridity. Typically, natural gas well pad construction involves stripping topsoil to allow for equipment to be on level ground and placing it into a stockpile. After well pad construction is complete, soil is respread and seeded across a large portion of the initial disturbance to initiate interim reclamation. With the advent of new extraction technologies (e.g., directional drilling), it is not always known how many individual wells will be placed on a given well pad until results from exploratory tests are examined. Previous research has shown soil disturbance during natural gas well pad construction and subsequent reclamation in cold, arid environments is highest at the stripping and respreading phases, with minimal soil activity occurring during the stockpile phase. Other research has shown that additional soil disturbances after reclamation is initiated may exacerbate soil damage, limiting revegetation potential. However, no studies have been conducted to determine if soil stockpile age impacts vegetation emergence. Here, we examine soil stockpiles which are 1-7 years old in the Jonah Infill natural gas field for vegetation emergence and vegetation cover using an image analysis software called SamplePoint. In a ten-week greenhouse experiment, we found vegetation cover across stockpile age-classes increased uniformly during the study period but that there was no significant difference in rate of vegetation cover increase or percent vegetation cover over time. These findings suggest it may be better to keep soil stockpiled in cold, arid natural gas fields when it is uncertain if additional construction activities will be required on a well pad location rather than respreading soil with a chance that redisturbance is necessary.

ecology↗

Early seral vegetation communities increase insect abundance and diversity in a semiarid natural gas field during early and late growing season

Insects are critical components of terrestrial ecosystems and are often considered ecosystem engineers. Due to the vast amount of ecosystem services they provide, because statistically valid samples can be captured in short durations, and because they respond rapidly to environmental change, insects have been used as indicators of restoration success and ecosystem functionality. In Wyoming (USA), thousands of acres of land surface has been disturbed to extract natural resources. While traditional reclamation practices of these lands focused on site stabilization and weed control, more recent efforts have been made to restore ecosystem services. It has been suggested that a spatial and temporal mosaic of flowering species will benefit insect populations. In this study, we compared early seral reclamation sites (i.e., well pads undergoing interim reclamation) to reference areas at two points within a growing season. We found reference ecosystems were devoid of forb species, while one year old reclaimed sites contained late-season blooming Rocky Mountain beeplant (Cleome serrulata) and three-four year old well pads contained early-season blooming perennial forb species, mainly western yarrow (Achillea millefolium). We compared insect abundance and family richness on 6 well pads with early season perennial forbs and 6 well pads with the late season annual forb, Rocky Mountain beeplant to insect communities on adjacent reference areas. A total of 237 insects were found on early season reclaimed sites compared to 84 on reference sites, while 858 insects were found on late season reclaimed sites compared to 40 on reference sites. Insect abundance and family richness was significantly higher on reclaimed well pads compared to reference areas at both points in the growing season. We also found interesting differences in abundance at family levels.

ecology↗