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Item Open Access Data associated with "Resilience and regime shifts: Do novel communities impede ecological recovery in a historically metal-contaminated stream?"(Colorado State University. Libraries, 2019) Wolff, Brian A.; Duggan, Sam B.; Clements, William H.Novel communities that result from exposure to contaminants and other anthropogenic stressors often persist in ecosystems that have experienced regime shifts. Because these systems may not return to pre-disturbance conditions after removal of the stressor, understanding the ecological consequences of regime shifts has important implications for how restoration success is defined. Long-term observational studies can potentially identify regime shifts in disturbed ecosystems; however, experimental approaches may be necessary to demonstrate their ecological consequences. We report results of a long-term (28 year) observational study and a series of stream mesocosm experiments that investigated a regime shift in a mining-contaminated watershed. We tested the hypothesis that establishment of a novel, metal-tolerant macroinvertebrate community in a previously contaminated stream impeded recovery of sensitive species, despite significant improvements in water quality over the past two decades. Despite significant improvements in water quality, abundance and species richness, we observed persistent changes in community composition and trophic structure downstream from a former source of metal contamination. Downstream communities were dominated by large, metal-tolerant caddisflies that likely impeded colonization by metal-sensitive groups (e.g., grazing mayflies). Mesocosm experiments conducted with reference and downstream communities demonstrated that novel communities retained their tolerance to metals, but were significantly more sensitive to other stressors. We suggest that the failure of downstream communities to recover represented a contaminant-induced regime shift that resulted from the sustained dominance of metal-tolerant species. Restoration ecologists generally consider increased species diversity or abundance of recreationally/commercially important species as indicators of restoration success. However, few stream restoration projects have quantified ecological resilience, and none have included a significant experimental component. Our research is the first to experimentally demonstrate that novel communities in a stream recovering from historical metal pollution have lower resilience to other (e.g., non-metal) stressors. These results have important implications for how restoration success is defined. In systems where restoration to pre-disturbance conditions is unlikely, a better understanding of the ecological resilience of novel communities may be critical for assessing the restoration success. We suggest that resilience to novel stressors is an important indicator of restoration effectiveness that may be applicable in other aquatic ecosystems.Item Open Access Data associated with "The importance of extreme rainfall events and their timing in a semi-arid grassland"(Colorado State University. Libraries, 2020) Post, Alison; Knapp, AlanClimate change is intensifying the hydrologic cycle globally, increasing both the size and frequency of extreme precipitation events, or deluges. Arid and semi-arid ecosystems are expected to be particularly responsive to this change because their ecological processes are largely driven by distinct soil moisture pulses. However, since soil moisture, air temperature, and plant phenology vary throughout the growing season, deluges will likely have differing impacts on these systems depending on when they occur. We conducted a field experiment to assess how the seasonal timing (early, middle, or late growing season) of a single deluge (70 mm precipitation event) altered key ecological processes in the semi-arid shortgrass steppe of North America. Regardless of timing, a single deluge stimulated most ecosystem processes, but a deluge at mid-season caused the greatest increase in soil respiration, canopy greenness, aboveground net primary production (ANPP), and growth and flowering of the dominant plant species (Bouteloua gracilis). In contrast, belowground net primary production (BNPP) was insensitive to deluge timing, with a consistent BNPP increase in all the deluge treatments that was almost twice as large as the ANPP response. This BNPP response was largely driven by enhanced root production at 10-20 cm, rather than 0-10 cm, soil depths. In a semi-arid ecosystem, a single deluge can have season-long impacts on many ecosystem processes, but responses can be mediated by event timing. Therefore, predicting responses of semi-arid ecosystems to more dynamic precipitation regimes, and subsequent impacts on the global carbon budget, will require knowledge of how deluge magnitude, frequency, and timing are being altered by climate change.Item Open Access Data associated with “How Big is Big Enough? Surprising Responses of a Semi-arid Grassland to Increasing Deluge Size”(Colorado State University. Libraries, 2020) Post, Alison; Knapp, AlanClimate change has intensified the hydrologic cycle globally, increasing the magnitude and frequency of large precipitation events, or deluges. Dryland ecosystems are expected to be particularly responsive to increases in deluge size, as their ecological processes are largely dependent on distinct soil moisture pulses. To better understand how increasing deluge size will affect ecosystem function, we conducted a field experiment in a native semi-arid shortgrass steppe (Colorado, USA). We quantified ecological responses to a range of deluge sizes, from moderate to extreme, with the goal of identifying response patterns and thresholds beyond which ecological processes would not increase further (saturate). Using a replicated regression approach, we imposed single deluges that ranged in size from 20 to 120 mm (82.3rd to > 99.9th percentile of historical event size) on undisturbed grassland plots. We quantified pre- and post-deluge responses in soil moisture, soil respiration, and canopy greenness, as well as leaf water potential, growth, and flowering of the dominant grass species (Bouteloua gracilis). We also measured end of season above- and below-ground net primary production (ANPP, BNPP). As expected, this water-limited ecosystem responded strongly to the applied deluges, but surprisingly, most variables increased linearly with deluge size. We found little evidence for response thresholds within the range of deluge sizes imposed, at least during a dry year. Instead, response patterns reflected the linear increase in the duration of elevated soil moisture (2-22 days) with increasing event size. Flowering of B. gracilis and soil respiration responded particularly strongly to deluge size (14- and 4-fold increases, respectively), as did ANPP and BNPP (~60% increase for both). Overall, our results suggest that this semi-arid grassland will respond positively and linearly to predicted increases in deluge size, and that event sizes will need to exceed historical magnitudes before responses saturate.Item Open Access Dataset associated with the manuscript: “Divergent belowground allocation patterns of winter wheat shape rhizosphere microbial communities and nitrogen cycling activities”(Colorado State University. Libraries, 2021) Kelly, Courtland; Fonte, Steven; Haddix, MichellePlant roots add carbon (C) -rich rhizodeposits to the soil, which can alter microbial activity and nitrogen (N) cycling with implications for N availability and uptake by plants. We evaluated root architecture, rhizodeposit C, and microbial community structure and function across a breeding gradient of twelve winter wheat genotypes and examined how these rhizosphere traits were related to the availability and uptake of N from fresh cover crop residues in the soil. We traced wheat-derived C into soil and microbial pools using continuous isotopic labelling (13C-CO2) and applied 15N labelled plant residues to quantify plant and microbial uptake of residue-derived N. Wheat genotypes differed in root C allocation patterns, influencing N cycling. Thicker roots released more C into soil, which enhanced N mineralization through stimulation of the microbial biomass. Microbial biomass increased N-cycling enzyme activity and residue N-uptake by wheat. Microbial communities did not differ between wheat genotypes but were strongly related to patterns in root C allocation, and several genera showed strong relationships with root C deposition and N uptake. The microbial community associated with extractable root-derived C was structurally different from the community associated with residue N uptake, indicating the N-cycling response to exudation was not necessarily carried out by the same microbial community members as those stimulated by rhizosphere C inputs. Our results indicate that differential patterns of rhizodeposition and associated belowground C allocation strategies in winter wheat can alter microbial communities and influence cycling and plant availability of residue N. Ecologically-based nutrient management in agricultural systems should consider the role of crop root traits and associated microbiomes to optimize soil nutrient dynamics.Item Open Access Dataset associated with “Characterizing the importance of denitrification for N2O production in soils using natural abundance and isotopic labelling techniques”(Colorado State University. Libraries, 2021) Stuchiner, EmilyNitrous oxide (N2O), a potent greenhouse gas that contributes significantly to climate change, is emitted mostly from soils by a suite of microbial metabolic pathways that are nontrivial to identify, and subsequently, to manage. Using either natural abundance or enriched stable isotope methods has aided in identifying microbial sources of N2O, but each approach has limitations. Here, we conducted a novel pairing of natural abundance and enriched assays on two dissimilar soils, hypothesizing this pairing would better constrain microbial sources of N2O. We incubated paired natural abundance and enriched soils from a corn agroecosystem and a subalpine forest in the laboratory at 10-95% soil saturation for 28 hr. The natural abundance method measured intramolecular site preference (SP) from emitted N2O, whereas the enriched method measured emitted 15N2O from soils amended with 15N-labelled substrate. The isotopic composition of emitted N2O was measured using a laser-based N2O isotopic analyzer, yielding two key findings. First, both methods revealed that denitrification was the primary source of N2O in all soils: isotopic enrichment revealed clear NO3- reduction to N2O, while SP indicated a likely combination of fungal and bacterial denitrification. Second, we quantified, to our knowledge for the first time, persistent (>55%) β-position-specific enrichment in N2O emitted from 15NO3- -amended soils. This counter-intuitive enrichment pattern could be indicative of co-denitrification, an understudied but potentially important contributor to N2O emissions. Our work revealed the ubiquity of denitrification among the soils tested. Future pairings of natural abundance and enriched methods could better characterize diverse denitrification pathways.Item Open Access Dataset associated with “Using isotope pool dilution to understand how organic carbon additions affect N2O consumption in diverse soils”(Colorado State University. Libraries, 2022) Stuchiner, Emily R.; von Fischer, J. C.Nitrous oxide (N2O) is a formidable greenhouse gas with warming potential ~300x greater than CO2. However, its emissions to the atmosphere have gone largely unchecked because the microbial and environmental controls governing N2O emissions have proven difficult to manage. The microbial process N2O consumption is the only know biotic pathway to remove N2O from soil pores and therefore reduce N2O emissions. Consequently, manipulating soils to increase N2O consumption by organic carbon (OC) additions has steadily gained interest. However, the response of N2O emissions to different OC additions are inconsistent, and it is unclear if lower N2O emissions are due to increased consumption, decreased production, or both. Simplified and systematic studies are needed to evaluate the efficacy of different OC additions on N2O consumption. We aimed to manipulate N2O consumption by amending soils with OC compounds (succinate, acetate, propionate) more directly available to denitrifiers. We hypothesized that N2O consumption is OC-limited and predicted these denitrifier-targeted additions would lead to enhanced N2O consumption and increased nosZ gene abundance. We incubated diverse soils in the laboratory and performed a 15N2O isotope pool dilution assay to disentangle microbial N2O emissions from consumption using laser-based spectroscopy. We found that amending soils with OC increased gross N2O consumption in six of eight soils tested. Furthermore, three of eight soils showed Increased N2O Consumption and Decreased N2O Emissions (ICDE), a phenomenon we introduce in this study as an N2O management ideal. All three ICDE soils had low soil OC content, suggesting ICDE is a response to relaxed C-limitation wherein C additions promote soil anoxia, consequently stimulating the reduction of N2O via denitrification. We suggest, generally, OC additions to low OC soils will reduce N2O emissions via ICDE. Future studies should prioritize methodical assessment of different, specific, OC-additions to determine which additions show ICDE in different soils.Item Open Access Dataset associated with “What’s in a name? The paradox of citizen science and community science”(Colorado State University. Libraries, 2021) Lin Hunter, Danielle; Newman, Gregory; Balgopal, MeenaCitizen science has expanded ecological and environmental sciences by making possible studies across greater spatial and temporal scales while incorporating local expertise and interests that might otherwise be overlooked. Broadly, citizen science involves the public in the process of science. However, it continues to struggle to engage diverse participants. Citizen science project coordinators are increasingly trying to promote inclusivity by rebranding as “community science” to avoid the term “citizen.” Rebranding efforts, while well-intentioned, are uninformed by research, as we lack an evidenced-based understanding of these terms. We distributed a survey to those who participate in citizen and community science. We found differences in how well known and accepted the terms are, who is perceived as initiating and benefiting from the projects, and associated levels of inclusivity. Our findings have important implications for those involved in citizen and community science seeking to better describe projects in the future.Item Open Access Dataset associated with: "Intentional mentoring should increase inclusivity in ecology"(Colorado State University. Libraries, 2021) Stuchiner, Emily; Lin Hunter, Danielle; Neuwald, Jennifer; Webb, Colleen; Balgopal, MeenaHigh quality mentoring relationships can be pivotal to recruitment, retention, and long-term persistence in ecology majors and careers. The graduate-undergraduate student mentoring relationship can become uniquely important during activities like ecological fieldwork. However, graduate students often have little experience as research mentors, which can lead to negative research experiences for undergraduate mentees. Given the potential for mentoring relationships to impact people’s decisions on pursuing ecological studies and/or careers, we created and piloted a mentoring professional development program designed around intentional mentoring. Intentional mentoring requires that mentors preemptively identify what skills and knowledge their mentee should develop as well as the practices to help mentees develop these competencies. Our rationale for using intentional mentoring was that it has the potential to increase mentors’ and mentees’ awareness of issues around diversity, equity, inclusion, and social justice (DEIJ) in research experiences, in addition to developing professional competencies. To evaluate our program, we conducted focus group interviews with graduate and undergraduate student participants following a multi-week mentoring training workshop, the primary aspect of the program. Participants described an increased valuation of intentional mentoring and a desire to be more intentional in their mentoring relationships. Graduate student mentors described an increased desire to be more intentional mentors, whereas undergraduate mentees described an increased desire to seek mentors with whom they could develop intentional relationships. Undergraduates also better recognized the importance of academic mentors. Based on our evaluation, we posit that intentional mentoring can increase the retention and persistence of students with diverse identities in ecology by fostering a sense of belonging. We advocate the implementation of mentoring training workshops as a part of academic ecological programs to increase inclusion in our discipline.Item Open Access Dataset for the reproduction of the item response model in "More robust local governance suggests positive effects of long-term community conservation"(Colorado State University. Libraries, 2020) Salerno, J.Community-based conservation (CBC) is essential to promoting biodiversity protection and livelihood development. Despite significant financial and institutional investment, performance of CBC interventions is mixed, with shortcomings especially evident in wildlife-based CBC in Africa. CBC outcomes are typically evaluated through household livelihood gains, or through policy analysis at higher administrative levels such as the central state. Surprisingly, village or local governance capacity is often missing from project assessment. Through a controlled study, we evaluate CBC interventions at multiple scales in Tanzania. Employing Bayesian multilevel latent trait models, we find that CBC participation predicts stronger village governance institutions. Additionally, compared to control villages, CBC villages have more local civic organizations and small business enterprise, but do not experience greater elite capture of public goods. Together, and in the absence of direct CBC benefits provisioned to households or signs of success at the higher level of multi-village CBC bodies, these findings point to the possibility that village-level governance institutions can adapt in beneficial ways to prolonged CBC interventions.Item Open Access MODIS Monthly Fog and Low Cloud Cover Rasters 2000-2022(Colorado State University. Libraries, 2022) Werner, Zackary; Choi, Christopher Tsz Hin; Winter, Anna; Vorster, Anthony G.; Berger, Anika; O'Shea, Kristen; Evangelista, Paul; Woodward, BrianThe MODIS Monthly Fog and Low Cloud Cover Rasters 2000-2022 dataset contains fog and low cloud cover (FLCC) observations summarized into days per month along the California and Southern Oregon Coast from 2000-2022. This dataset accompanies the publication https://doi.org/10.1016/j.rsase.2022.100832, which describes the methodology for creating this dataset. The dataset can also be viewed through a Google Earth Engine web application https://christopherchoi98.users.earthengine.app/view/modis-fog-detection-app.Item Open Access Soil CO2 flux from plots with various fire histories at the Konza Prairie Biological Station(Colorado State University. Libraries, 2020) Slette, IngridThere is abundant evidence that ongoing changes to fire regimes are affecting the global carbon cycle. However, uncertainty about how the response to an individual fire may be affected by historical factors such as the time elapsed since the last fire or the long-term fire frequency makes it difficult to predict the effects of changing fire regimes on carbon cycling. We took advantage of a 35-year fire frequency experiment (annual fire, fire every two or four years, and unburned treatments) in a native, mesic grassland to assess how fire history (time since last fire and long-term frequency) affects soil CO2 flux, a key ecosystem carbon output. We found that historic fire frequency altered the magnitude of the response to fire, with greater post-fire soil CO2 flux stimulation in annually burned grassland than in grassland burned every two or four years. Fire-induced flux increases persisted for two years after fire in grassland burned every four years. Though we found that fire also stimulated aboveground net primary productivity (ANPP), a key ecosystem carbon input, this stimulation was not altered by long-term fire frequency and didn't persist into later years, unlike soil CO2 flux. This asymmetry emphasizes the importance of measuring impacts both aboveground and belowground. Our findings demonstrate that fire history modifies a key response to individual fires in this grassland. To understand and predict the dynamics of important global carbon cycle components, it is necessary to consider not only the presence vs. absence of fire, but also the long-term fire regime.Item Open Access Supporting information (SI) for Gill et al. 2016 manuscript(Colorado State University. Libraries, 2015) Gill, Brian A.; Kondratieff, Boris C.; Casner, Kayce L.; Encalada, Andrea C.; Flecker, Alex S.; Gannon, Dustin; Ghalambor, Cameron K.; Guayasamin, Juan M.; Poff, N. LeRoy; Simmons, Mark P.; Thomas, Steven A.; Zamudio, Kelly R.; Funk, W. ChrisItem Open Access Writing matters: increasing undergraduate cell biology literacy through writing-to-learn activities-dataset(Colorado State University. Libraries, 2015-2016) Balgopal, Meena M.; Casper, Anne Marie A.; Laybourn, Paul J.; Birsch, Ellen; Wallace, Alison M.; Dahlberg, StevenBiology educators need instructional strategies to improve student learning and achievement, especially in foundational courses when students are presented with vast amounts of content knowledge. Writing-to-learn (WTL) tasks in lecture courses can help biology students improve the quality of their arguments and increase content knowledge. WTL activities can model how scientists use inductive reasoning to design studies and arguments; encourage revision of ideas; support peer review and discussion; and help with writing-to-communicate tasks. Our WTL interventions include the use of graphic organizers, iterative writing, peer evaluation, and self-evaluation. We examined the effects of WTL on content knowledge, performance (grades), and argumentation. WTL is associated with 1) increased use of abstract concepts over the course of the semester in two WTL interventions (intense and moderate); 2) increased performance for some students (first generation, women, and minorities); and dialectical argumentation (persuasive) compared to demonstration arguments (expository).