Repository for Oil and Gas Energy Research (ROGER)

Abstract:
Unconventional natural gas development (fracking) has been a rapidly expanding technique used for the extraction of natural gas from the Marcellus Shale formation in Pennsylvania. There remains a knowledge gap regarding the ecological impacts of fracking, especially regarding the long-term health of native Brook trout (Salvelinus fontinalis) populations. During the summer of 2015, Brook trout were sampled from twelve streams located in forested, northwestern Pennsylvania in order to evaluate the impacts of fracking on Brook trout. Four stream sites were undisturbed (no fracking activity), three had a developed well pad without fracking activity, and five had active fracking with natural gas production. Liver tissue was isolated from two to five fish per stream and underwent RNA-Seq analysis to identify differentially expressed genes between ecosystems with differing fracking status. Data were analyzed individually and with samples pooled within-stream to account for hierarchical data structure and variation in sample coverage within streams. Differentially expressed and differentially alternatively spliced genes had functions related to lipid and steroid metabolism, mRNA processing, RNA polymerase and protein regulation. Unique to our study, genes related to xenobiotic and stress responses were found as well as potential markers for endocrine disruption and saline adaptation that were identified in watersheds with active fracking activity. These results support the utility of RNA-Seq to assess trout health and suggest detrimental impacts of fracking on sensitive trout populations.

Abstract:
We sampled headwater streams to characterize impacts of unconventional shale gas development (SGD) on aquatic ecosystems. The study area was relatively un-impacted by confounding activities. Intensity of SGD over the study decreased then increased again but not to levels seen the first year. Shale gas development was associated with increased, but non-impaired, water pH and specific conductance during the latter part of the study. Metrics summarizing macroinvertebrate assemblages were better on average in un-impacted reaches. A genus-level multimetric index of biotic integrity was statistically lower downstream of impacts compared to upstream, but only in the year when SGD activity was most intense. Multivariate analyses indicated that assemblages diverged in similarity downstream compared to upstream of impacts in the first and last years of the study when SGD activity was elevated. Assemblage divergence was related to variation in water quality. Indicator species analysis linked a few key taxa to un-impacted conditions in the first year of the study; tolerant taxa were indicators for impacted conditions later in the study. Our study links SGD to weak negative changes in water quality and benthic macroinvertebrates, which may have negative consequences to food quality for wildlife that rely on aquatic prey within forested systems.

Abstract:
Our study goal was to investigate the impact of biocides and nanoparticles (NPs) on the microbial diversity in a hydraulic fracturing impacted stream. Biocides and NPs are known for their antimicrobial properties and controlling microbial growth. Previous work has shown that biocides can alter the microbial community composition of stream water and may select for biocide-resistant bacteria. Additional studies have shown that nanoparticles can also alter microbial community composition. However, previous work has often focused on the response to a single compound. Here we provide a more thorough analysis of the microbial community response to three different biocides and three different nanoparticles. A microcosm-based study was undertaken that exposed stream microbial communities to either biocides or NPs. Our results showed a decrease in bacterial abundance with different types of nanoparticles, but an increase in microbial abundance in biocide-amended treatments. The microbial community composition (MCC) was distinct from the controls in all biocide and NP treatments, which resulted in differentially enriched taxa in the treatments compared to the controls. Our results indicate that NPs slightly altered the MCC compared to the biocide-treated microcosms. After 14 days, the MCC in the nanoparticle-treated conditions was similar to the MCC in the control. Conversely, the MCC in the biocide-treated microcosms was distinct from the controls at day 14 and distinct from all conditions at day 0. This finding may point to the use of NPs as an alternative to biocides in some settings.

Abstract:
Revenues from oil and gas development play a key role in the economies of many states in the United States, but there are environmental concerns such as local air and water pollution, land cover changes and fragmentation, and negative effects on wildlife. These concerns were exacerbated as oil and gas production reached historic highs due to the expanded use of hydraulic fracturing technology beginning in the mid-2000s. This paper examines the influence of oil and gas development on breeding bird communities in the High Plains ecoregion of Colorado between 2003 and 2018. Specifically, we investigated whether oil and gas drilling or production affected species richness or evenness of bird communities. Our findings indicate that a decrease in producing well density or the number of producing fracking wells were associated with an increase in evenness of the overall bird community and grassland species richness, but disturbances from well drilling generally did not have a statistically significant influence on bird communities. We also found that a decrease in tree cover was associated with an increase in species richness and evenness of the overall bird community.

Abstract:
Diluted bitumen, also known as dilbit, is transported by rail and pipeline across Canada and the United States. Due to the fewer number of studies characterizing the toxicity of dilbit, a dilbit spill poses an unknown risk to freshwater aquatic ecosystems. In the following study, we compared the impact of early-life exposure to conventional and unconventional crude oils on the optomotor behavior, reproductive success, and transgenerational differences in gene expression in zebrafish and their progeny. For exposures, water accommodated fractions (WAFs) of crude oil were generated using a 1:1000 oil to water ratio for 3 different crudes; mixed sweet blend (MSB), medium sour composite (MSC) and dilbit. All three oils generated unique volatile organic compound (VOC) and polycyclic aromatic compound (PAC) profiles. Of the WAFs tested, only dilbit decreased the eye size of 2 dpf larvae, and only MSB exposed larvae had an altered behavioral response to a visual simulation of a predator. Early-life exposure to crude oil had no lasting impact on reproductive success of adult fish; however, each oil had unique impacts on the basal gene expression of the somatically exposed offspring. In this study, the biological effects differed between each of the oils tested, which implied chemical composition plays a critical role in determining the sublethal toxicity of conventional and unconventional crude oils in freshwater ecosystems.

Abstract:
Anthropogenic activities can lead to the loss, fragmentation, and alteration of wildlife habitats. I reviewed the recent literature (2014–2019) focused on the responses of avian, mammalian, and herpetofaunal species to oil and natural gas development, a widespread and still-expanding land use worldwide. My primary goals were to identify any generalities in species’ responses to development and summarize remaining gaps in knowledge. To do so, I evaluated the directionality of a wide variety of responses in relation to taxon, location, development type, development metric, habitat type, and spatiotemporal aspects.

Abstract:
Conservation partners are concerned that oil and gas development in the Prairie Pothole Region may reduce the abundance of breeding duck pairs using associated wetland habitat. We conducted wetland-based surveys for breeding pairs of 5 species of dabbling ducks in the Bakken oil field during 2015–2017 across a gradient of oil and gas development intensity to test the hypothesis that the abundance of breeding duck pairs on survey wetlands would decrease as the development of oil and gas resources increased. We included covariates traditionally used to predict breeding duck pairs (i.e. wetland size and class) and a spatiotemporal index of disturbance when developing zero-inflated Poisson models relating pair abundance to environmental predictors. Similar to past analyses, pair abundance was strongly associated with wetland size. Our results were mixed and suggested that the abundance of early and late nesting species was positively and negatively related, respectively, to an index of disturbance that was largely driven by oil and gas development. Regardless of the direction of the relationship, effect sizes were small and not considered biologically significant. Our findings indicate that in our study area, strategies to conserve wetland resources for breeding duck pairs should not deviate from previous prioritization metrics within the range of oil and gas development we observed. We believe that our findings may have implications to similar landscapes within the Bakken.• Since 2008, the oil and gas development in the North Dakota and Montana portion of Bakken Oil Formation has increased dramatically.• There is considerable overlap between the Bakken Oil Formation and important Prairie Pothole Region wetlands critical for waterfowl production.• We surveyed breeding Blue-winged Teal, Gadwall, Mallard, Northern Pintail, and Northern Shoveler pairs from 2015 to 2017 to determine if breeding pair abundance was lower in proximity to a gradient of disturbance from oil and gas development.• Our results were mixed but regardless, changes in pair abundance were small and we considered the potential biological effect to be small.• We recommend that existing conservation tools continue to be used to identify important grassland and wetland resources in the region given that we did not observe a biologically significant reduction in breeding duck pairs.

Abstract:
Europe PMC is an archive of life sciences journal literature., Evaluating the Impact of Hydraulic Fracturing on Streams using Microbial Molecular Signatures.

Abstract:
In 2010, twenty-eight bovines on a Pennsylvania beef farm were exposed to a hydraulic fracturing wastewater leak on their grazing pasture. Over the following year, eleven out of seventeen calves born to the exposed animals died. The farmers framed the deaths as outside normal deathly production on the farm, while state institutions claimed the deaths resulted from the farmers’ negligence, framing them as ordinary. I draw on necropolitics to examine how death becomes a normalized mode of capital production in agri-food systems, investigating how the wastewater spill and calves’ deaths ruptured the everyday production of bovine death. The paper argues that death must occur in prescribed sites and at approved times to function as a site of value accumulation in capitalist agriculture. I examine how the spill and calf death events emerged through promiscuous entanglements between overlapping modes of capital extraction across and through the site of the farm. Using assemblages, I trace unruly, promiscuous encounters at this food-energy contact zone to consider how the calves’ deaths render visible the space-time boundaries used to manage more-than-human mortality as a metabolic process in livestock production, and highlight disparate power relations between diverse necropolitical actors and modes of governance.

Abstract:
Few studies have examined the land use, fragmentation, and conversion impacts from siting unconventional oil and gas wells on farmland. This exploratory GIS study examined these issues in the Bakken shale region in North Dakota. A total of 3,577 well pads containing 6,201 wells located on farmland were digitized and examined in this study. The findings indicate that in addition to land used for agricultural purposes (such as cropland and rangeland), other land types such as native woodlands and wetlands have also been converted to well pads and associated infrastructure. The single-well and multi-well pad footprints in this study were higher than the industrial estimates. The overall average well pad footprint is 6.45 acres while the average single-well pad and multi-well pad footprint is 5.26 acres and 8.60 acres, respectively. Eighty two percent of well pads had 1-2 wells sited on them. The findings show that the well pad footprint differed based on whether the well pad was located in a core or periphery county, on rangeland or cropland, and that single-well well pad footprint increased over time. Several issues that require further research are outlined.

Abstract:
The widespread application of directional drilling and hydraulic fracturing technologies expanded oil and gas (OG) development to previously inaccessible resources. A single OG well can generate millions of liters of wastewater, which is a mixture of brine produced from the fractured formations and injected hydraulic fracturing fluids (HFFs). With thousands of wells completed each year, safe management of OG wastewaters has become a major challenge to the industry and regulators. OG wastewaters are commonly disposed of by underground injection, and previous research showed that surface activities at an Underground Injection Control (UIC) facility in West Virginia affected stream biogeochemistry and sediment microbial communities immediately downstream from the facility. Because microbially driven processes can control the fate and transport of organic and inorganic components of OG wastewater, we designed a series of aerobic microcosm experiments to assess the influence of high total dissolved solids (TDS) and two common HFF additives—the biocide 2,2-dibromo-3-nitrilopropionamide (DBNPA) and ethylene glycol (an anti-scaling additive)—on microbial community structure and function. Microcosms were constructed with sediment collected upstream (background) or downstream (impacted) from the UIC facility in West Virginia. Exposure to elevated TDS resulted in a significant decrease in aerobic respiration, and microbial community analysis following incubation indicated that elevated TDS could be linked to the majority of change in community structure. Over the course of the incubation, the sediment layer in the microcosms became anoxic, and addition of DBNPA was observed to inhibit iron reduction. In general, disruptions to microbial community structure and function were more pronounced in upstream and background sediment microcosms than in impacted sediment microcosms. These results suggest that the microbial community in impacted sediments had adapted following exposure to OG wastewater releases from the site. Our findings demonstrate the potential for releases from an OG wastewater disposal facility to alter microbial communities and biogeochemical processes. We anticipate that these studies will aid in the development of useful models for the potential impact of UIC disposal facilities on adjoining surface water and shallow groundwater.

Abstract:
Hydraulic fracturing has become widely used in recent years to access vast global unconventional sources of oil and gas. This process involves the injection of proprietary mixtures of water and chemicals to fracture shale formations and extract the hydrocarbons trapped within. These injection fluids, along with minerals, hydrocarbons, and saline waters present within the formations being drilled into, return to the surface as flowback and produced water (FPW). FPW is a highly complex mixture, containing metals, salts and clay, as well as many organic chemicals, including polycyclic aromatic hydrocarbons such as phenanthrene. The present study sought to determine the effects of temperature on the accumulation of phenanthrene in rainbow trout (Oncorhynchus mykiss). This model organism resides in rivers overlapping the Montney and Duvernay formations, both highly developed formations for hydraulic fracturing. Rainbow trout acclimated to temperatures of 4, 13 and 17°C were exposed to either 5% or 20% FPW, as well as saline mixtures representing the exact ionic content of FPW to determine the accumulation of radiolabelled 14C phenanthrene within the gill, gut, liver and gallbladder. FPW exposure reduced the overall accumulation of phenanthrene in a manner most often similar to high salinity exposure, indicating that the high ionic strength of FPW is the primary factor affecting accumulation. Accumulation was different at the temperature extremes (4 and 17°C), although no consistent relationship was observed between temperature and accumulation across the observed tissues. These results indicate that several physiological responses occur as a result of FPW exposure and water temperature change which dictate phenanthrene uptake, particularly in the gills. Temperature (and seasonality) alone cannot be used to model the potential accumulation of polycyclic aromatic hydrocarbons after FPW spills.

Abstract:
Hydraulic fracturing flowback and produced water (FPW) is a highly complex and heterogenous wastewater by-product of hydraulic fracturing practices. To date, no research has examined how FPW exposure to freshwater biota may affect energetic homeostasis following subsequent induction of detoxification processes. Rainbow trout (Oncorhynchus mykiss) were acutely exposed for 48 h to either 2.5% or 7.5% FPW, and hepatic metabolism was assessed either immediately or following a 3-week recovery period. Induction of xenobiotic metabolism was observed with an 8.8-fold increase in ethoxyresorufin-O-deethylase (EROD) activity after 48 h exposure to 7.5% FPW, alongside a 10.3-fold increase in the mRNA abundance of cyp1a, both of which returned to basal level after three weeks. Glucose uptake capacity was elevated by 6.8- and 12.9-fold following 2.5% and 7.5% FPW exposure, respectively, while alanine uptake was variable. Activity measurements and mRNA abundance of key enzymes involved in hepatic metabolism indicated that aerobic metabolism was maintained with exposure, as was glycolysis. Gluconeogenesis, as measured by phosphoenolpyruvate carboxykinase (PEPCK) activity, decreased by ~30% 48 h following 2.5% FPW exposure and ~20% 3 weeks after 7.5% FPW exposure. The abundance of pepck mRNA activity followed similar, yet non-significant, trends. Finally, a delayed increase in amino acid catabolism was observed, as glutamate dehydrogenase (GDH) activity was increased 2-fold in 7.5% FPW exposed fish when compared to saline control fish at the 3-week time point. We provide evidence to suggest that although hepatic metabolism is altered following acute FPW exposure, metabolic homeostasis generally returns 3-weeks post-exposure.

Abstract:
Publicly available toxicological studies on wastewaters associated with unconventional oil and gas (UOG) activities in offshore regions are nonexistent. The current study investigated the impact of hydraulic fracturing-generated flowback water (HF-FW) on whole organism swimming performance/respiration and cardiomyocyte contractility dynamics in mahi-mahi (Coryphaena hippurus—hereafter referred to as “mahi”), an organism which inhabits marine ecosystems where offshore hydraulic fracturing activity is intensifying. Following exposure to 2.75% HF-FW for 24 h, mahi displayed significantly reduced critical swimming speeds (Ucrit) and aerobic scopes (reductions of ∼40 and 61%, respectively) compared to control fish. Additionally, cardiomyocyte exposures to the same HF-FW sample at 2% dilutions reduced a multitude of mahi sarcomere contraction properties at various stimulation frequencies compared to all other treatment groups, including an approximate 40% decrease in sarcomere contraction size and a nearly 50% reduction in sarcomere relaxation velocity compared to controls. An approximate 8-fold change in expression of the cardiac contractile regulatory gene cmlc2 was also seen in ventricles from 2.75% HF-FW-exposed mahi. These results collectively identify cardiac function as a target for HF-FW toxicity and provide some of the first published data on UOG toxicity in a marine species.

Abstract:
Chemical spills in streams can impact ecosystem or human health. Typically, the public learns of spills from reports from industry, media, or government rather than monitoring data. For example, ∼1300 spills (76 ≥ 400 gallons or ∼1500 L) were reported from 2007 to 2014 by the regulator for natural gas wellpads in the Marcellus shale region of Pennsylvania (U.S.), a region of extensive drilling and hydraulic fracturing. Only one such incident of stream contamination in Pennsylvania has been documented with water quality data in peer-reviewed literature. This could indicate that spills (1) were small or contained on wellpads, (2) were diluted, biodegraded, or obscured by other contaminants, (3) were not detected because of sparse monitoring, or (4) were not detected because of the difficulties of inspecting data for complex stream networks. As a first step in addressing the last problem, we developed a geospatial-analysis tool, GeoNet, that analyzes stream networks to detect statistically significant changes between background and potentially impacted sites. GeoNet was used on data in the Water Quality Portal for the Pennsylvania Marcellus region. With the most stringent statistical tests, GeoNet detected 0.2% to 2% of the known contamination incidents (Na ± Cl) in streams. With denser sensor networks, tools like GeoNet could allow real-time detection of polluting events.

Abstract:
Unconventional oil and gas (UOG) drilling has expanded rapidly across the United States, including in the Fayetteville Shale formation in north-central Arkansas where drilling began in 2004. As one of the oldest regions of UOG activity in the United States, this area has experienced significant land-use changes, specifically development of natural habitat and agricultural land for gas infrastructure. In recent years, drilling of new wells has stopped and production has declined. By 2017, 1038 wells had ceased production and been abandoned, which makes them eligible for land reclamation. However, most of these sites (80%) have not been reclaimed and continue to cause losses in ecosystem services. If reclamation was performed on lands associated with abandoned infrastructure, we estimate more than $2 million USD annually in agricultural, timber, and carbon sequestration values would be gained. These benefits far outweigh the costs of reclamation, especially since the benefits accrue over time and reclamation is a short-term cost. Our estimates indicate a 2–4 year break-even time period when cumulative ecosystem services benefits will outweigh reclamation costs. We predicted a well-abandonment rate of 155 per year until 2050 when 98% of wells will be abandoned, which indicates great potential for future ecosystem services restoration. Thus, we recommend that Arkansans at the government and citizen level work to restore lands impacted by UOG development in the Fayetteville Shale region so that their value to landowners and society can be recovered, which will enhance long-term economic and environmental benefits.

Abstract:
The challenge of balancing biodiversity protection with economic growth is epitomized by the development of renewable and unconventional energy, whose adoption is aimed at stemming the impacts of global climate change, yet has outpaced our understanding of biodiversity impacts. We evaluated the potential conflict between biodiversity protection and future electricity generation from renewable (wind farms, run-of-river hydro) and non-renewable (shale gas) sources in British Columbia (BC), Canada using three metrics: greenhouse gas (GHG) emissions, electricity cost, and overlap between future development and conservation priorities for several fish and wildlife groups - small-bodied vertebrates, large mammals, freshwater fish – and undisturbed landscapes. Sharp trade-offs in global versus regional biodiversity conservation exist for all energy technologies, and in BC they are currently smallest for wind energy: low GHG emissions, low-moderate overlap with top conservation priorities, and competitive energy cost. GHG emissions from shale gas are 1000 times higher than those from renewable sources, and run-of-river hydro has high overlap with conservation priorities for small-bodied vertebrates. When all species groups were considered simultaneously, run-of-river hydro had moderate overlap (0.56), while shale gas and onshore wind had low overlap with top conservation priorities (0.23 and 0.24, respectively). The unintended cost of distributed energy sources for regional biodiversity suggest that trade-offs based on more diverse metrics must be incorporated into energy planning.

Abstract:
Unconventional methods of oil and natural gas extraction have been a growing part of North America's energy sector for the past 20-30 years. Technologies such as horizontal hydraulic fracturing have facilitated the exploitation of geologic reserves that were previously resistant to standard drilling approaches. However, the environmental risks associated with hydraulic fracturing are relatively understudied. One such hazard is the wastewater by-product of hydraulic fracturing processes: flowback and produced water (FPW). During FPW production, transport, and storage, there are many potential pathways for environmental exposure. In the current review, toxicological hazards associated with FPW surface water contamination events and potential effects on freshwater biota are assessed. This review contains an extensive survey of chemicals commonly associated with FPW samples from shale formations across North America and median 50% lethal concentration values (LC50) of corresponding chemicals for many freshwater organisms. We identify the characteristics of FPW which may have the greatest potential to be drivers of toxicity to freshwater organisms. Notably, components associated with salinity, the organic fraction, and metal species are reviewed. Additionally, we examine the current state of FPW production in North America and identify the most significant obstacles impeding proper risk assessment development when environmental contamination events of this wastewater occur. Findings within this study will serve to catalyze further work on areas currently lacking in FPW research, including expanded whole effluent testing, repeated and chronic FPW exposure studies, and toxicity identification evaluations.

Abstract:
The present research examines the combined role of the message and source of a news article in persuading political partisans about an environmental policy. In a series of three experiments, we presented participants (total N = 3457) with a realistic news article summarizing scientific evidence concerning the environmental and economic costs and benefits of hydraulic fracturing (fracking). The article’s message was manipulated to support either a conservative (pro-fracking) or liberal (anti-fracking) policy and was attributed to either a conservative news source (Fox News) or a liberal one (MSNBC). Participants who read pro-fracking articles were generally more supportive of fracking than those who read anti-fracking articles, regardless of whether articles were from an ideologically friendly or unfriendly source. Consistent with previous research, however, participants perceived articles with ideologically unfriendly messages to have worse methods than articles with ideologically friendly messages. Finally, liberal participants showed some reduction in resistance to ideologically unfriendly messages coming from an ideologically friendly source, but conservative participants did not. Implications for politicization of environmental policy and future research are discussed.

Abstract:
Hydraulic fracturing of horizontal wells is a cost effective means for extracting oil and gas from low permeability formations. Hydraulic fracturing often produces considerable volumes of flowback and produced water (FPW). FPW associated with hydraulic fracturing has been shown to be a complex, often brackish mixture containing a variety of anthropogenic and geogenic compounds. In the present study, the risk of FPW releases to aquatic systems was studied using the model benthic invertebrate, Lumbriculus variegatus and field-collected FPW from a fractured well in Alberta. Acute, chronic, and pulse toxicity were evaluated to better understand the implications of accidental FPW releases to aquatic environments. Although L. variegatus is thought to have a high tolerance to many stressors, acute toxicity was significant at low concentrations (i.e. high dilutions) of FPW (48 h LC50: 4–5%). Chronic toxicity (28 d)of FPW in this species was even more pronounced with LC50s (survival/reproduction) and EC50s (total mass) at dilutions as low as 0.22% FPW. Investigations evaluating pulse toxicity (6 h and 48 h exposure) showed a significant amount of latent mortality occurring when compared to the acute results. Additionally, causality in acute and chronic bioassays differed as acute toxicity appeared to be primarily driven by salinity, which was not the case for chronic toxicity, as other stressors appear to be important as well. The findings of this study show the importance of evaluating multiple exposure regimes, the complexity of FPW, and also shows the potential aquatic risk posed by FPW releases.

Abstract:
Recent technological progresses have unlocked tremendous shale energy resources, leading to increased production of oil and gas and a variety of new environmental pollution issues in the United States. One such example is management of produced waters, which are often disposed of via deep well injection. Produced water injection has been linked to induced seismicity. Thus, there are strong incentives for alternative management strategies that come with new, uncertain environmental risks. This paper summarizes studies of sediment pollution due to oil and gas production. The goal is to highlight potential environmental risks associated with produced water management, including long-term contamination of sediments.

Abstract:
The number of horizontally drilled shale oil and gas wells in the United States has increased from nearly 28,000 in 2007 to nearly 127,000 in 2017, and research has suggested the potential for the development of shale resources to affect nearby stream ecosystems. However, the ability to generalize current studies is limited by the small geographic scope as well as limited breadth and integration of measured chemical and biological indicators parameters. This study tested the hypothesis that a quantifiable, significant relationship exists between the density of oil and gas (OG) development, increasing stream water concentrations of known geochemical tracers of OG extraction, and the composition of benthic macroinvertebrate and microbial communities. Twenty-five headwater streams that drain lands across a gradient of shale gas development intensity were sampled. Our strategy included comprehensive measurements across multiple seasons of sampling to account for temporal variability of geochemical parameters, including known shale OG geochemical tracers, and microbial and benthic macroinvertebrate communities. No significant relationships were found between the intensity of OG development, shale OG geochemical tracers, or benthic macroinvertebrate or microbial community composition, whereas significant seasonal differences in stream chemistry were observed. These results highlight the importance of considering spatial and temporal variability in stream chemistry and biota and not only the presence of anthropogenic activities in a watershed. This comprehensive, integrated study of geochemical and biological variability of headwater streams in watersheds undergoing OG development provides a robust framework for examining the effects of energy development at a regional scale.

Abstract:
Shale-gas production could impact freshwater quality through contamination of the physical and chemical habitat (e.g., fracturing fluids, untreated or treated effluent) or development-related impacts. Despite environmental concerns, information is lacking to support biomonitoring as a diagnostic tool to assess impacts of shale-gas production. We characterized water quality and biota in areas of high shale gas potential (Early Carboniferous bedrock in New Brunswick, Canada) and surrounding geologic areas, and we assessed patterns in benthic macroinvertebrate (BMI) and fish assemblages. Early Carboniferous stations differed primarily based on water chemistry, and BMI were associated with a gradient in conductivity and temperature across geologic classes. Concordance analysis indicated similar classification of stations by both organism groups, though fish were more related to turbidity and nutrients. Concordance among fish and BMI was strongest at high conductivity, Early Carboniferous stations. These results suggest that geology plays a strong role in driving abiotic habitats and biotic communities of streams, even at small spatial scales. Furthermore, they suggest BMI and fish can provide complementary information for biomonitoring in shale-gas development areas, with BMI responding to increased ion concentrations from surface water contamination, and fish responding to changes in nutrients and turbidity resulting from development.

Abstract:
Epigenetic mechanisms such as DNA methylation may vary in response to environmental stressors and introduce adaptive or maladaptive gene expression within and among wild bird populations. We examined the association between DNA methylation and demographic characteristics of the Louisiana Waterthrush Parkesia motacilla in territories with and without disturbance from shale gas development in a Central Appalachian watershed during 2013–2015. We also evaluated the degree to which an individual’s methylated state was subject to change across years in individuals that returned over the course of more than one breeding season (i.e. recaptures). Overall, population methylation differed between adult male and female Waterthrush where adult males generally had fewer methylated restriction sites. Methylation also differed between adult females and nestlings. Age influenced methylation in both adult males and females with a decrease in methylation with age, although adult female recaptures had increased methylation with age. Adult males were variably methylated between shale gas undisturbed and disturbed areas at a population and restriction site (i.e. loci) level, where restriction sites were predominately less methylated in shale gas-disturbed areas. Barium (Ba) and strontium (Sr) data from 2013 feather samples showed adult males had fewer methylated sites at higher concentrations of Ba and Sr, whereas nestlings displayed no correlation of methylation to Ba and Sr concentrations. Adult females displayed increased methylation with increased Sr, a trend also seen year to year in adult female recaptures. Overall, results of our study suggest sex-specific influences of shale gas development on gene expression that may affect long-term population survival and fitness.

Abstract:
Abstract. Over the past decade, the United States has seen a rapid increase in oil and gas extraction from areas where resources were previously thought to be

Abstract:
The land-use impacts of the rapid expansion of U.S. oil and gas infrastructure since the early 2000s are a focus of local, state, and federal policymakers. Agriculture is the dominant land use in many areas with active energy development. Prior studies find that energy development displaces agriculture and assume that this effect is both permanent and homogeneous. We take a novel approach, analyzing landowners' capacity to both anticipate displaced production prior to the drilling of oil and gas wells, and reclaim some land once wells are in production. Using North Dakota's Bakken Shale as a case study, we merge agricultural land-use data from 2006 to 2014 with locations and drilling dates of oil and gas wells. We then use panel fixed-effects models to estimate the spatially- and intertemporally-heterogeneous effects of additional wells on agricultural land. We find that drilling is associated with reduced surrounding crop cover and increased fallow acreage. Importantly, the duration of these effects differs across agricultural land covers, and effects are in some cases temporary. Our analysis suggests that overlooking dynamic land use impacts may overestimate the cumulative net impact of oil and gas development on agricultural land uses by up to a factor of two.

Abstract:
Organohalides are routinely detected in fluid produced from hydraulically fractured oil and natural-gas wells, yet the origin and fate of these compounds remain largely unknown. Because few organohalides are disclosed as fracturing fluid additives, one suspected formation mechanism is the reaction of geogenic halides oxidized by injected additives with natural or anthropogenic organic carbon. However, the potential role of microorganisms in organohalide cycling is currently unknown. Here, we uncover the microorganisms and enzymatic systems that contribute to organohalide transformations during hydraulic fracturing through nontarget organohalide chemical analysis and metagenomics. Twenty organohalide compounds were identified in fluid samples produced from two Marcellus Shale natural-gas wells, comprising five structural classes. Genes encoding halogenation and dehalogenation mechanisms were identified in metagenomes assembled from produced fluids collected from four Appalachian Basin natural-gas wells. Metagenomic results show the presence of non-heme chloroperoxidases, enzymes that generate peracetic acid, which can react with dissolved halides to form highly oxidizing hypohalous acid, a halogenation agent for geogenic or anthropogenic organic matter. Microbial organohalide transformation/mineralization could proceed through hydrolytic dehalogenation, with enzymes inferred to operate on haloacetates, haloacids, and haloalkanes of varying carbon chain lengths, some of which are present in these wells. These results indicate that microorganisms may play an underappreciated role in direct and indirect organohalide transformations in hydraulically fractured oil and gas systems.

Abstract:
Production of unconventional oil and gas continues to rise, but the effects of high-density hydraulic fracturing (HF) activity near aquatic ecosystems are not fully understood. A commonly used biocide in HF, 2,2-dibromo-3-nitrilopropionamide (DBNPA), was studied in microcosms of HF-impacted vs. HF-unimpacted surface water streams to (1) compare the microbial community response, (2) investigate DBNPA degradation products based on past HF exposure, and (3) compare the microbial community response differences and similarities between the HF biocides DBNPA and glutaraldehyde. The microbial community responded to DBNPA differently in HF-impacted vs. HF-unimpacted microcosms in terms of 16S rRNA gene copies quantified, alpha and beta diversity, and differential abundance analyses of microbial community composition through time. The difference in microbial community changes affected degradation dynamics. HF-impacted microbial communities were more sensitive to DBNPA, causing the biocide and byproducts of the degradation to persist for longer than in HF-unimpacted microcosms. Seventeen DBNPA byproducts were detected, many of them not widely known as DBNPA byproducts. Many of the believed to be uncharacterized brominated byproducts detected may pose environmental and health impacts. Similar taxa were able to tolerate glutaraldehyde and DBNPA, however DBNPA was not as effective for microbial control as indicated by a smaller overall decrease of 16S rRNA gene copies/mL after exposure to the biocide and a more diverse set of taxa was able to tolerate it. These findings suggest that past HF activity in streams can affect the microbial community response to environmental perturbation such as the biocide DBNPA. Importance Unconventional oil and gas activity can affect pH, total organic carbon, and microbial communities in surface water altering their ability to respond to new environmental and/or anthropogenic perturbations. These findings demonstrate that DBNPA, a common hydraulic fracturing (HF) biocide, affects microbial communities differently as a consequence of past HF exposure, persisting longer in HF-impacted waters. These findings also demonstrate that DBNPA has low efficacy in environmental microbial communities regardless of HF impact. These findings are of interest, as understanding microbial responses is key for formulating remediation strategies in UOG impacted environments. Moreover, some of DBNPA degradation byproducts are even more toxic and recalcitrant than DBNPA itself, and this work identifies novel brominated degradation byproducts formed.

Abstract:
The development of shale petroleum resources has industrialized rural landscapes. We investigated how traffic from energy development expands and intensifies the road-effect zone through increased dust exposure, and how birds and invertebrates inhabiting the road-effect zone in agricultural areas of the Bakken region might be affected by dust exposure. We used dust collectors, trail cameras, and sweep-netting at increasing distances from unpaved roads to determine dust deposition, relative bird abundance, and invertebrate abundance, respectively. We found that traffic associated with fracking along unpaved roads emitted substantial dust 180 m into adjacent crop fields. But neither bird abundance or behavior, nor invertebrate abundance or community composition, appeared to be affected by dust or traffic. These findings suggest that wildlife in previously intensified agricultural landscapes like crop fields are resilient to intensification from energy development, but the same might not be true for wildlife in previously undisturbed habitat.

Abstract:
Flowback and produced water (FPW) is a complex, often brackish, solution formed during the process of hydraulic fracturing. Despite recent findings on the short-term toxicity of FPW on aquatic biota, longer-term impacts of FPW on fish have not yet been investigated and the mechanisms of chronic effects remain unknown. The aim of the present study was to observe the effect of a diluted FPW on ionoregulatory endpoints in the rainbow trout Oncorhynchus mykiss, following a 28-d sub-chronic exposure. A salinity-matched control solution (SW), recreating the salt content of the FPW, was used to differentiate the specific effect of the salts from the effects of the other FPW components (i.e. organics and metals). Overall, fish ionoregulation was not impacted by the chronic exposure. An accumulation of strontium (Sr) and bromide (Br) occurred in the plasma of the FPW-exposed fish only, however no change of plasma ions (Na, K, Cl, Ca, Mg) was observed in SW- or FPW-exposed fish. Similarly, exposures did not alter branchial activity of the osmoregulatory enzymes sodium/potassium ATPase and proton ATPase. Finally, FPW exposure resulted in modifications of gill morphology over time, with fish exposed to the fluid displaying shorter lamellae and increased interlamellar-cell mass. However, these effects were not distinct from morphological changes that also occurred in the gills of control groups.

Abstract:
Understanding how energy infrastructure affects local biodiversity and soil characteristics is important for informing restoration and management. However, the rapid rate of modern oil and gas development is beyond the limit of current knowledge and mitigation strategies. In a mixed-grass prairie in western Oklahoma, we assessed the presence and directionality of biodiversity and environmental gradients associated with energy development in an observational framework. Specifically, we sampled arthropods, vegetation, soil temperature, and soil moisture on the edge of active oil well pads and at 1 m, 10 m, and 100 m away from the well pad. Though variable, the abundance and biomass of most arthropod orders was lower on the pad and 1 m away compared with 10 m and 100 m away, suggesting that the pad itself negatively influenced arthropods but that these effects were limited in spatial extent. However, vegetation structure and composition varied more extensively. Vegetation height, shrub cover, and warm season grass cover increased sixfold, threefold, and fourfold, respectively, from on the oil pad to 100 m away. Forb cover was 5× higher at 10 m from the well pad than on the pad, 1 m away, and 100 m away from the pad. Soil surface temperature was lower at sites farther from well pads, but we found no relationship between soil moisture and distance from well pad. Well pad effects on arthropods and soil temperature appear to be limited to the pad itself, though long-term changes in vegetation structure extend significantly beyond the well footprint and demand a better understanding of the effectiveness of restoration activities around well pads.

Abstract:
Hydraulic fracturing has become a well-established and widespread technology for the extraction of oil and natural gas. Hydraulic fracturing fluids (HFFs) are widely varied and contain many chemicals that are toxic to human and ecological health. HFFs are often spilled on surface soils where their fate and transport is uncertain. In this study, six representative mixtures of HFFs were incubated with a surface soil in bench-scale microcosms, and the microbial community was analyzed over 78 days. The chemical oxygen demand decreased over time, although a significant recalcitrant fraction was found for four of the six amended fluids. With Illumina MiSeq sequencing of a 16S ribosomal RNA (rRNA) gene amplification and follow-through quantitative polymerase chain reaction (qPCR) assays, 24 bacterial taxa closely related to known species were identified to be enriched by at least one of the representative HFFs. These taxa are mostly closely related to well-known xenobiotic degraders, however, the composition of the enrichment was highly unique for each representative HFF. The results indicate that the complex mixtures of biocides and other components elicit unique bacterial community responses in the same soil, thus suggesting that the bioremediation pathways of HFF constituents in soils may differ based on exact HFF composition.

Abstract:
Metagenomes from hydraulically fractured wells over time identified viral operational taxonomic units predicted to actively infect dominant bacteria, and in vitro experiments show that viral lysis of these hosts can release metabolites important for fermentation.

Abstract:
To inform sustainable energy development, it is important to understand the ecological effects of historical and current production practices and the persistence of those effects. The Williston Basin is one of North America's largest oil production areas and overlaps the Prairie Pothole Region, an area densely populated with wetlands that provide important wildlife habitat. Although historical disposal practices that released chloride-rich waters (brines) produced during oil extraction into the environment are no longer used, brine spills still occur frequently. We sampled 33 wetlands for three amphibian species in Montana and North Dakota during 2015–2017, primarily on National Wildlife Refuges, and used N-mixture models to determine how abundance varied with evidence of brine contamination. To provide insight into effects of historical versus contemporary contamination, we also estimated the association of well density and age with water quality and amphibian abundance. Abundance of boreal chorus frog (Pseudacris maculata) larvae declined most rapidly in response to increased chloride (range: 0.04–17,500 mg/L), followed by the northern leopard frog (Lithobates [Rana] pipiens) and barred tiger salamander (Ambystoma mavortium). Water quality and population- and community-level abundance of amphibians were more strongly related to nearby wells (≤800 m) installed before 1982 than to wells installed since 1982. These results suggest historical brine management practices were the primary driver of contamination and reduced amphibian abundance in wetlands we sampled, reflecting multi-decadal ecological effects. These persistent effects also underscore the critical need for tools to restore landscapes affected by brine contamination.

Abstract:
In the western U.S., produced water from oil and gas wells discharged to surface water augments downstream supplies used for irrigation and livestock watering. Here we investigate six permitted discharges on three neighboring tributary systems in Wyoming. During 2013–16, we evaluated radium activities of the permitted discharges and the potential for radium accumulation in associated stream sediments. Radium activities of the sediments at the points of discharge ranged from approximately 200–3600 Bq kg−1 with elevated activities above the background of 74 Bq kg−1 over 30 km downstream of one permitted discharge. Sediment as deep as 30 cm near the point of discharge had radium activities elevated above background. X-ray diffraction and targeted sequential extraction of radium in sediments indicate that radium is likely coprecipitated with carbonate and, to a lesser extent, sulfate minerals. PHREEQC modeling predicts radium coprecipitation with aragonite and barite, but over-estimates the latter compared to observations of downstream sediment, where carbonate predominates. Mass-balance calculations indicate over 3 billion Bq of radium activity (226Ra + 228Ra) is discharged each year from five of the discharges, combined, with only 5 percent of the annual load retained in stream sediments within 100 m of the effluent discharges; the remaining 95 percent of the radium is transported farther downstream as sediment-associated and aqueous species.

Abstract:
We related Louisiana Waterthrush (Parkesia motacilla) demographic response and nest survival to benthic macroinvertebrate aquatic prey and to shale gas development parameters using models that accounted for both spatial and non-spatial sources of variability in a Central Appalachian USA watershed. In 2013, aquatic prey density and pollution intolerant genera (i.e., pollution tolerance value <4) decreased statistically with increased waterthrush territory length but not in 2014 when territory densities were lower. In general, most demographic responses to aquatic prey were variable and negatively related to aquatic prey in 2013 but positively related in 2014. Competing aquatic prey covariate models to explain nest survival were not statistically significant but differed annually and in general reversed from negative to positive influence on daily survival rate. Potential hydraulic fracturing runoff decreased nest survival both years and was statistically significant in 2014. The EPA Rapid Bioassessment protocol (EPA) and Habitat Suitability Index (HSI) designed for assessing suitability requirements for waterthrush were positively linked to aquatic prey where higher scores increased aquatic prey metrics, but EPA was more strongly linked than HSI and varied annually. While potential hydraulic fracturing runoff in 2013 may have increased Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness, in 2014 shale gas territory disturbance decreased EPT richness. In 2014, intolerant genera decreased at the territory and nest level with increased shale gas disturbance suggesting the potential for localized negative effects on waterthrush. Loss of food resources does not seem directly or solely responsible for demographic declines where waterthrush likely were able to meet their foraging needs. However collective evidence suggests there may be a shale gas disturbance threshold at which waterthrush respond negatively to aquatic prey community changes. Density-dependent regulation of their ability to adapt to environmental change through acquisition of additional resources may also alter demographic response.

Abstract:
Potential for shale gas production is linked to regional geology, which influences water chemistry of freshwater systems. However, there has been little work to establish baseline ecological conditions of rivers within areas of shale gas development. In this study, water chemistry and monitoring metrics for fish and benthic macroinvertebrates were compared among varying-sized streams in New Brunswick, Canada with different underlying geology. Water chemistry and biotic community structure differed strongly among geological age classes. Early Carboniferous stations, with highest potential for shale gas production, had the highest ions, invertebrate abundances, and richness of invertebrates and fish, with strongest differences between Early Carboniferous and older bedrock classes. A reference condition model indicated numerous sites deviated from normal, but this was not specific to geological classes, and reflected the lack of model reference site coverage. These results highlight the importance of selecti...

Abstract:
Oil and gas development is changing the landscape in many regions of the United States and globally. However, the nature, extent, and magnitude of landscape change and development, and precisely how this development compares to other ongoing land conversion (e.g. urban/sub-urban development, timber harvest) is not well understood. In this study, we examine land conversion from oil and gas infrastructure development in the upper Susquehanna River basin in Pennsylvania and New York, an area that has experienced much oil and gas development over the past 10 years. We quantified land conversion in terms of forest canopy geometric volume loss in contrast to previous studies that considered only areal impacts. For the first time in a study of this type, we use fine-scale lidar forest canopy geometric models to assess the volumetric change due to forest clearing from oil and gas development and contrast this land change to clear cut forest harvesting, and urban and suburban development. Results show that oil and gas infrastructure development removed a large volume of forest canopy from 2006 to 2013, and this removal spread over a large portion of the study area. Timber operations (clear cutting) on Pennsylvania State Forest lands removed a larger total volume of forest canopy during the same time period, but this canopy removal was concentrated in a smaller area. Results of our study point to the need to consider volumetric impacts of oil and gas development on ecosystems, and to place potential impacts in context with other ongoing land conversions.

Abstract:
We conducted a large-scale assessment of unconventional oil and gas (UOG) development effects on brook trout (Salvelinus fontinalis) distribution. We compiled 2231 brook trout collection records from the Upper Susquehanna River Watershed, USA. We used boosted regression tree (BRT) analysis to predict occurrence probability at the 1:24,000 stream-segment scale as a function of natural and anthropogenic landscape and climatic attributes. We then evaluated the importance of landscape context (i.e., pre-existing natural habitat quality and anthropogenic degradation) in modulating the effects of UOG on brook trout distribution under UOG development scenarios. BRT made use of 5 anthropogenic (28% relative influence) and 7 natural (72% relative influence) variables to model occurrence with a high degree of accuracy [Area Under the Receiver Operating Curve (AUC) = 0.85 and cross-validated AUC = 0.81]. UOG development impacted 11% (n = 2784) of streams and resulted in a loss of predicted occurrence in 126 (4%). Most streams impacted by UOG had unsuitable underlying natural habitat quality (n = 1220; 44%). Brook trout were predicted to be absent from an additional 26% (n = 733) of streams due to pre-existing non-UOG land uses (i.e., agriculture, residential and commercial development, or historic mining). Streams with a predicted and observed (via existing pre- and post-disturbance fish sampling records) loss of occurrence due to UOG tended to have intermediate natural habitat quality and/or intermediate levels of non-UOG stress. Simulated development of permitted but undeveloped UOG wells (n = 943) resulted in a loss of predicted occurrence in 27 additional streams. Loss of occurrence was strongly dependent upon landscape context, suggesting effects of current and future UOG development are likely most relevant in streams near the probability threshold due to pre-existing habitat degradation.

Abstract:
Production of natural gas using unconventional technologies has risen as demand for alternative fuels has increased. Impacts on the environment from waste generated from these processes are largely unexplored. In particular, the outcomes of organismal exposure to hydraulic fracturing waste have not been rigorously evaluated. We evaluated the effects of exposure to surrogate hydraulic fracturing waste (HF waste) on mucosal bacterial community structure of the brook trout (Salvelinus fontinalis) epidermis. Brook trout are fish native to streams at risk to HF waste exposure. Here, fish were exposed to four treatments (control, 0.00%; low, 0.01%; medium, 0.10%; and high, 1.0% concentrations) of surrogate HF waste synthesized to mimic concentrations documented in the field. Epidermal mucus samples were collected and assessed 15 days post-exposure to determine if the associated bacterial community varied among treatments. We observed differences in epidermal mucosal bacterial community composition at multiple taxonomic scales among treatments. These community changes reflected compositional differences in taxa dominance and community similarity rather than losses or gains in taxonomic richness. The dominant bacterial genus that explained the greatest variation in community structure between exposed and unexposed fish was Flavobacterium. Two genera associated with salmonid diseases, Flavobacterium and Pseudomonas, were statistically more abundant in high treatments than controls. These results suggest that exposure to low levels of HF waste influences bacterial colonization and may lead to a disruption that favors bacterial populations associated with fish disease.

Abstract:
The environmental impacts of hydraulic fracturing, particularly those of surface spills in aquatic ecosystems, are not fully understood. The goals of this study were to (1) understand the effect of previous exposure to hydraulic fracturing fluids on aquatic microbial community structure and (2) examine the impacts exposure has on biodegradation potential of the biocide glutaraldehyde. Microcosms were constructed from hydraulic fracturing-impacted and nonhydraulic fracturing-impacted streamwater within the Marcellus shale region in Pennsylvania. Microcosms were amended with glutaraldehyde and incubated aerobically for 56 days. Microbial community adaptation to glutaraldehyde was monitored using 16S rRNA gene amplicon sequencing and quantification by qPCR. Abiotic and biotic glutaraldehyde degradation was measured using ultra-performance liquid chromatography--high resolution mass spectrometry and total organic carbon. It was found that nonhydraulic fracturing-impacted microcosms biodegraded glutaraldehyde faster than the hydraulic fracturing-impacted microcosms, showing a decrease in degradation potential after exposure to hydraulic fracturing activity. Hydraulic fracturing-impacted microcosms showed higher richness after glutaraldehyde exposure compared to unimpacted streams, indicating an increased tolerance to glutaraldehyde in hydraulic fracturing impacted streams. Beta diversity and differential abundance analysis of sequence count data showed different bacterial enrichment for hydraulic fracturing-impacted and nonhydraulic fracturing-impacted microcosms after glutaraldehyde addition. These findings demonstrated a lasting effect on microbial community structure and glutaraldehyde degradation potential in streams impacted by hydraulic fracturing operations.

Abstract:
Directional well drilling and hydraulic fracturing has enabled energy production from previously inaccessible resources, but caused vegetation conversion and landscape fragmentation, often in relatively undisturbed habitats. We improve forecasts of future ecological impacts from unconventional oil and gas play developments using a new, more spatially-explicit approach. We applied an energy production outlook model, which used geologic and economic data from thousands of wells and three oil price scenarios, to map future drilling patterns and evaluate the spatial distribution of vegetation conversion and habitat impacts. We forecast where future well pad construction may be most intense, illustrating with an example from the Eagle Ford Shale Play of Texas. We also illustrate the ecological utility of this approach using the Spot-tailed Earless Lizard (Holbrookia lacerata) as the focal species, which historically occupied much of the Eagle Ford and awaits a federal decision for possible Endangered Species Act protection. We found that ~17,000–45,500 wells would be drilled 2017‒2045 resulting in vegetation conversion of ~26,485–70,623 ha (0.73–1.96% of pre-development vegetation), depending on price scenario ($40–$80/barrel). Grasslands and row crop habitats were most affected (2.30 and 2.82% areal vegetation reduction). Our approach improves forecasts of where and to what extent future energy development in unconventional plays may change land-use and ecosystem services, enabling natural resource managers to anticipate and direct on-the-ground conservation actions to places where they will most effectively mitigate ecological impacts of well pads and associated infrastructure.

Abstract:
Horizontal drilling and hydraulic fracturing extraction procedures have become increasingly present in Pennsylvania where the Marcellus Shale play is largely located. The potential for long-term environmental impacts to nearby headwater stream ecosystems and aquatic bacterial assemblages is still incompletely understood. Here, we perform high-throughput sequencing of the 16 S rRNA gene to characterize the bacterial community structure of water, sediment, and other environmental samples (n = 189) from 31 headwater stream sites exhibiting different histories of fracking activity in northwestern Pennsylvania over five years (2012–2016). Stream pH was identified as a main driver of bacterial changes within the streams and fracking activity acted as an environmental selector for certain members at lower taxonomic levels within stream sediment. Methanotrophic and methanogenic bacteria (i.e. Methylocystaceae, Beijerinckiaceae, and Methanobacterium) were significantly enriched in sites exhibiting Marcellus shale activity (MSA+) compared to MSA− streams. This study highlighted potential sentinel taxa associated with nascent Marcellus shale activity and some of these taxa remained as stable biomarkers across this five-year study. Identifying the presence and functionality of specific microbial consortia within fracking-impacted streams will provide a clearer understanding of the natural microbial community’s response to fracking and inform in situ remediation strategies.

Abstract:
Hydraulic fracturing for oil and gas can alter the biological integrity of small streams. Persistent and stable community composition and ecological function define integrity that can change in response to alterations. An inherent challenge is identifying ecological indicators supported by adequate data prior to ecosystem alterations, unknown interactions among alterations, and the appropriate scale to measure indicators. Oil and gas extraction has increased in the last decade in density and geographic expanse across the U.S. in regions without a history of extraction. Disturbances associated with extraction are land clearing for supporting infrastructure, freshwater withdrawals, and possible chemical and wastewater water spills during drilling/fracturing, reuse, transport, and treatment. The well and pipeline density along with violations in a watershed are often used as indicators of biological risk at the reach (100 m) and small (<130 km2) watershed scale. The risk for measurable and biologically significant ecological alterations is probably increased by more wells placed close to stream channels, surface water withdrawal volumes that are not scaled to stream discharge seasonal and daily volumes and more frequent transport of wastewater and spills. Yet, the linkage between physical alterations to watersheds and the proposed ecological responses that may serve as endpoints associated with these changes remain largely unquantified. Ecological indicators that can be linked to watershed alterations (e.g. oil and gas pad density) and associated in-stream stressors (i.e. sedimentation) are needed to address rapid species loss and altered ecological functions.

Abstract:
West Texas’ Permian Basin, consisting of ancient marine rocks, is underlain by water-soluble rocks and multiple oil-rich formations. In the region that is densely populated with oil producing facilities, many localized geohazards, such as ground subsidence and micro-earthquakes, have gone unnoticed. Here we identify the localized geohazards in West Texas, using the satellite radar interferometry from newly launched radar satellites that provide radar images freely to public for the first time, and probe the causal mechanisms of ground deformation, encompassing oil/gas production activities and subsurface geological characteristics. Based on our observations and analyses, human activities of fluid (saltwater, CO2) injection for stimulation of hydrocarbon production, salt dissolution in abandoned oil facilities, and hydrocarbon extraction each have negative impacts on the ground surface and infrastructures, including possible induced seismicity. Proactive continuous and detailed monitoring of ground deformation from space over the currently operating and the previously operated oil/gas production facilities, as demonstrated by this research, is essential to securing the safety of humanity, preserving property, and sustaining the growth of the hydrocarbon production industry.

Abstract:
Recent research assessed how hydrocarbon and wind energy expansion has altered the North American landscape. Less understood, however, is how this energy development compares to other anthropogenic land use changes. Texas leads U.S. hydrocarbon production and wind power generation and has a rapidly expanding population. Thus, for ~47% of Texas (~324,000 km2), we mapped the 2014 footprint of energy activities (~665,000 oil and gas wells, ~5700 wind turbines, ~237,000 km oil and gas pipelines, and ~2000 km electrical transmission lines). We compared the footprint of energy development to non-energy-related activities (agriculture, roads, urbanization) and found direct landscape alteration from all factors affects ~23% of the study area (~76,000 km2), led by agriculture (~16%; ~52,882 km2). Oil and gas activities altered <1% of the study area (2081 km2), with 838 km2 from pipelines and 1242 km2 from well pad construction—and that the median Eagle Ford well pad is 7.7 times larger than that in the Permian Basin (16,200 vs. 2100 m2). Wind energy occupied <0.01% (~24 km2), with ~14 km2 from turbine pads and ~10 km2 from power transmission lines. We found that edge effects of widely-distributed energy infrastructure caused more indirect landscape alteration than larger, more concentrated urbanization and agriculture. This study presents a novel technique to quantify and compare anthropogenic activities causing both direct and indirect landscape alteration. We illustrate this landscape-mapping framework in Texas for the Spot-tailed Earless Lizard (Holbrookia lacerata); however, the approach can be applied to a range of species in developing regions globally.

Abstract:
Understanding long-term implications of energy development on ecosystem function requires establishing regional datasets to quantify past development and determine relationships to predict future development. The Piceance Basin in western Colorado has a history of energy production and development is expected to continue into the foreseeable future due to abundant natural gas resources. To facilitate analyses of regional energy development we digitized all well pads in the Colorado portion of the basin, determined the previous land cover of areas converted to well pads over three time periods (2002–2006, 2007–2011, and 2012–2016), and explored the relationship between number of wells per pad and pad area to model future development. We also calculated the area of pads constructed prior to 2002. Over 21million m2 has been converted to well pads with approximately 13million m2 converted since 2002. The largest land conversion since 2002 occurred in shrub/scrub (7.9million m2), evergreen (2.1million m2), and deciduous (1.3million m2) forest environments based on National Land Cover Database classifications. Operational practices have transitioned from single well pads to multi-well pads, increasing the average number of wells per pad from 2.5 prior to 2002, to 9.1 between 2012 and 2016. During the same time period the pad area per well has increased from 2030 m2 to 3504 m2. Kernel density estimation was used to model the relationship between the number of wells per pad and pad area, with these curves exhibiting a lognormal distribution. Therefore, either kernel density estimation or lognormal probability distributions may potentially be used to model land use requirements for future development. Digitized well pad locations in the Piceance Basin contribute to a growing body of spatial data on energy infrastructure and, coupled with study results, will facilitate future regional and national studies assessing the spatial and temporal effects of energy development on ecosystem function.

Abstract:
This paper considers the possible impacts of oil development on wildlife in the grasslands ecosystem, particularly in the province of Saskatchewan. The Bakken Formation, a major North American shale play, overlaps with one of the largest areas for grassland birds in Canada the US. Access to the oil is made possible through fracking and horizontal drilling, which are controversial techniques that have been regulated and banned in other parts of North America and the world. Drawing on analysis of recovery documents for listed species at risk, this paper illustrates that oil development is impacting species through habitat destruction, oil and noise pollution, invasive species, and road infrastructure. Current wildlife policy in Saskatchewan is inadequate to protect species at risk in the Bakken Formation.

Abstract:
The United States energy industry is transforming with the rapid development of alternative energy sources and technological advancements in fossil fuels. Two major changes include the growth of wind turbines and unconventional oil and gas. We measured land-use impacts and associated ecosystem services costs of unconventional gas and wind energy development within the Anadarko Basin of the Oklahoma Woodford Shale, an area that has experienced large increases in both energy sectors. Unconventional gas wells developed three times as much land compared to wind turbines (on a per unit basis), resulting in higher ecosystem services costs for gas. Gas wells had higher impacts on intensive agricultural lands (i.e., row crops) compared to wind turbines that had higher impacts on natural grasslands/pastures. Because wind turbines produced on average less energy compared to gas wells, the average land-use-related ecosystem cost per gigajoule of energy produced was almost the same. Our results demonstrate that both unconventional gas and wind energy have substantial impacts on land use, which likely affect wildlife populations and land-use-related ecosystem services. Although wind energy does not have the associated greenhouse gas emissions, we suggest that the direct impacts on ecosystems in terms of land use are similar to unconventional fossil fuels. Considering the expected rapid global expansion of these two forms of energy production, many ecosystems are likely to be at risk.

Abstract:
Shale gas development continues to outpace the implementation of best management practices for wildlife affected by development. We examined demographic responses of the Louisiana Waterthrush (Parkesia motacilla) to shale gas development during 2009–2011 and 2013–2015 in a predominantly forested landscape in West Virginia, USA. Forest cover across the study area decreased from 95% in 2008 to 91% in 2015, while the area affected by shale gas development increased from 0.4% to 3.9%. We quantified nest survival and productivity, a source–sink threshold, riparian habitat quality, territory density, and territory length by monitoring 58.1 km of forested headwater streams (n = 14 streams). Across years, we saw annual variability in nest survival, with a general declining trend over time. Of 11 a priori models tested to explain nest survival (n = 280 nests), 4 models that included temporal, habitat, and shale gas covariates were supported, and 2 of these models accounted for most of the variation in daily nest survival rate. After accounting for temporal effects (rainfall, nest age, and time within season), shale gas development had negative effects on nest survival. Population-level nest productivity declined and individual productivity was lower in areas disturbed by shale gas development than in undisturbed areas, and a source–sink threshold suggested that disturbed areas were more at risk of being sink habitat. Riparian habitat quality scores, as measured by a U.S. Environmental Protection Agency index and a waterthrush-specific habitat suitability index, differed by year and were negatively related to the amount of each territory disturbed by shale gas development. Territory density was not related to the amount of shale gas disturbance, but decreased over time as territory lengths increased. Overall, our results suggest a decline in waterthrush site quality as shale gas development increases, despite relatively small site-wide forest loss.