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At least 973 records · Page 54Linked to original sources
USGS2019

Diversity and abundance of wild bees in an agriculturally dominated landscape of eastern Colorado

Agricultural intensification has resulted in loss of natural and semi-natural habitats impacting several important ecosystem services. One group of organisms that has suffered greatly are the bees and hence pollination, the supporting ecosystem service they complete. The United States Department of Agriculture (USDA) Conservation Reserve Program (CRP) has implemented conservation practices designed to improve habitat for pollinators in agroecosystems by paying to recover environmentally sensitive agricultural land from production, and restoring them by planting native grass mixes, pollinator-friendly legumes and wildflowers. Our study, aimed at demonstrating the efficacy of this practice, measured diversity and abundance of wild bee genera in the agricultural landscape of eastern semiarid regions of Colorado, USA, where CRP practices were implemented. Over our 3-year study, we obtained a total of 16,207 bees belonging to 51 genera. We found inconsistent differences in number of bee genera and abundance of bees in CRP fields supplemented with wildflowers compared to those with conventional grass seed mix. However, we observed only a 40–80% overlap in bee genera between fields supplemented with wildflowers and those with grass seed mixes indicating that diversity was enhanced by having both habitats. With the caveat that 3 years is a very short period to see appreciable changes, our results suggest that recovering environmentally sensitive land can strengthen pollinator populations in landscapes dominated by agricultural activities. In addition, periodic evaluation and maintenance of these recovered lands will further support the efforts towards revitalization of ecosystem services in these areas.

Colorado↗
USGS2002

A case for using Plethodontid salamanders for monitoring biodiversity and ecosystem integrity of North American forests

Terrestrial salamanders of the family Plethodontidae have unique attributes that make them excellent indicators of biodiversity and ecosystem integrity in forested habitats. Their longevity, small territory size, site fidelity, sensitivity to natural and anthropogenic perturbations, tendency to occur in high densities, and low sampling costs mean that counts of plethodontid salamanders provide numerous advantages over counts of other North American forest organisms for indicating environmental change. Furthermore, they are tightly linked physiologically to microclimatic and successional processes that influence the distribution and abundance of numerous other hydrophilic but difficult-to-study forest-dwelling plants and animals. Ecosystem processes such as moisture cycling, food-web dynamics, and succession, with their related structural and microclimatic variability, all affect forest biodiversity and have been shown to affect salamander populations as well. We determined the variability associated with sampling for plethodontid salamanders by estimating the coefficient of variation (CV ) from available time-series data. The median coefficient of variation indicated that variation in counts of individuals among studies was much lower in plethodontids (27%) than in lepidoptera (93%), passerine birds (57%), small mammals (69%), or other amphibians (37–46%), which means plethodontid salamanders provide an important statistical advantage over other species for monitoring long-term forest health.

Conservation Biology↗
USGS2007

Hierarchical spatiotemporal matrix models for characterizing invasions

The growth and dispersal of biotic organisms is an important subject in ecology. Ecologists are able to accurately describe survival and fecundity in plant and animal populations and have developed quantitative approaches to study the dynamics of dispersal and population size. Of particular interest are the dynamics of invasive species. Such nonindigenous animals and plants can levy significant impacts on native biotic communities. Effective models for relative abundance have been developed; however, a better understanding of the dynamics of actual population size (as opposed to relative abundance) in an invasion would be beneficial to all branches of ecology. In this article, we adopt a hierarchical Bayesian framework for modeling the invasion of such species while addressing the discrete nature of the data and uncertainty associated with the probability of detection. The nonlinear dynamics between discrete time points are intuitively modeled through an embedded deterministic population model with density-dependent growth and dispersal components. Additionally, we illustrate the importance of accommodating spatially varying dispersal rates. The method is applied to the specific case of the Eurasian Collared-Dove, an invasive species at mid-invasion in the United States at the time of this writing. ?? 2006, The International Biometric Society.

Biometrics↗
USGS2024

Wetland creation and reforestation of legacy surface mines in the Central Appalachian Region (USA): A potential climate-adaptation approach for pond-breeding amphibians?

Habitat restoration and creation within human-altered landscapes can buffer the impacts of climate change on wildlife. The Forestry Reclamation Approach (FRA) is a coal surface mine reclamation practice that enhances reforestation through soil decompaction and the planting of native trees. Recently, wetland creation has been coupled with FRA to increase habitat available for wildlife, including amphibians. Our objective was to evaluate the response of pond-breeding amphibians to the FRA by comparing species occupancy, richness, and abundance across two FRA age-classes (2–5-year and 8–11-year reclaimed forests), traditionally reclaimed sites that were left to naturally regenerate after mining, and in mature, unmined forests in the Monongahela National Forest (West Virginia, USA). We found that species richness and occupancy estimates did not differ across treatment types. Spotted Salamanders ( Ambystoma maculatum ) and Eastern Newts ( Notophthalmus viridescens ) had the greatest estimated abundances in wetlands in the older FRA treatment. Additionally, larger wetlands had greater abundances of Eastern Newts, Wood Frogs ( Lithobates sylvaticus ), and Green Frogs ( L. clamitans ) compared to smaller wetlands. Our results suggest that wetland creation and reforestation increases the number of breeding sites and promotes microhabitat and microclimate conditions that likely maximize the resilience of pond-breeding amphibians to anticipated climate changes in the study area.

West Virginia↗
USGS1966

Geologic effects of the March 1964 earthquake and associated seismic sea waves on Kodiak and nearby islands, Alaska

Kodiak Island and the nearby islands constitute a mountainous landmass with an aggregate area of 4,900 square miles that lies at the western border of the Gulf of Alaska and from 20 to 40 miles off the Alaskan mainland. Igneous and metamorphic rocks underlie most of the area except for a narrow belt of moderately to poorly indurated rocks bordering the Gulf of Alaska coast and local accumulations of unconsolidated alluvial and marine deposits along the streams and coast. The area is relatively undeveloped and is sparsely inhabited. About 4,800 of the 5,700 permanent residents in the area live in the city of Kodiak or at the Kodiak Naval Station. The great earthquake, which occurred on March 27, 1964, at 5:36 p.m. Alaska standard time (March 28,1964, 0336 Greenwich mean time), and had a Richter magnitude of 8.4-8.5, was the most severe earthquake felt on Kodiak Island and its nearby islands in modern times. Although the epicenter lies in Prince William Sound 250 miles northeast of Kodiak—the principal city of the area—the areal distribution of the thousands of aftershocks that followed it, the local tectonic deformation, and the estimated source area of the subsequent seismic sea wave, all suggest that the Kodiak group of islands lay immediately adjacent to, and northwest of, the focal region from which the elastic seismic energy was radiated. The duration of strong ground motion in the area was estimated at 2½ minutes. Locally, the tremors were preceded by sounds audible to the human ear and were reportedly accompanied in several places by visible ground waves. Intensity and felt duration of the shocks during the main earthquake and aftershock sequence varied markedly within the area and were strongly influenced by the local geologic environment. Estimated Mercalli intensities in most areas underlain by unconsolidated Quaternary deposits ranged from VIII to as high as IX. In contrast, intensities in areas of upper Tertiary rock ranged from VII to VIII, and in areas of relatively well indurated lower Tertiary and Mesozoic rocks, from VI to VII. Local subsidence of as much as 10 feet was widespread in noncohesive granular deposits through compaction, flow, and sliding that resulted from vibratory loading during the earthquake. This phenomenon, which was largely restricted to saturated beach and alluvial deposits or artificial fill, was locally accompanied by extensive cracking of the ground and attendant ejection of water and water-sediment mixtures. Numerous landslides, including a wide variety of rockfalls, rockslides, and flows along steep slopes, were triggered by the long-duration horizontal and vertical accelerations during the earthquake. The landslides are most numerous in a narrow belt along the southeast coast of Kodiak Island and the nearby offshore islands. Their abundance appears to be related to an area underlain predominantly by Tertiary rocks. Temporary and permanent changes of level occurred after the earthquake in some wells, lakes, and streams throughout the area; ice was cracked, and the salinity of a few wells increased. Permanent change of water level at some localities appears to be related to readjustments of fracture porosity by earthquake-induced movements of bedrock blocks. Increased salinity of wells in coastal areas resulted from encroachment of seawater into aquifiers after subsidence during the earthquake, and to flooding of watersheds by seismic sea waves. Vertical displacements, both downward and upward, occurred throughout the area as a result of crustal warping along a northeast-trending axis. Most of Kodiak and all of Afognak, Shuyak, and adjacent islands are within a regional zone of subsidence whose trough plunges gently northeastward and approximately coincides with the mountainous backbone of Kodiak Island. Subsidence in excess of 6 feet occurred throughout the northern part of the zone-a maximum subsidence of 6½ feet having occurred on Marmot and, eastern Afognak Islands. Southeast of the axis of tectonic tilting, uplift of at least 2lh feet occurred in a narrow zone that includes most of the southeasterly capes of Kodiak Island, the southeastern half of Sitkalidak Island, and Sitkinak Island. The uplift is inferred to extend offshore over much or all of the continental shelf adjacent to the Kodiak group of islands. Within the affected area, tectonic subsidence, which was locally augmented by surficial subsidence of unconsolidated. deposits, caused widespread inundation of shorelines and attendant damage to intertidal organisms, nearshore terrestrial vegetation, and salmon-spawning areas. The most devastating effect of the earthquake on Kodiak Island and nearby islands resulted from seismic sea waves that probably originated along a linear zone of differential uplift in the Gulf of Alaska. A train of at least seven seismic sea waves, having initial periods of 50–55 minutes, struck along all the southeast coast of the island group from 38 to 63 minutes after the earthquake. The southeast shores were repeatedly washed by destructive waves having runup heights along exposed coasts of perhaps as much as 40 feet above existing tide level, and of 8–20 feet along protected shores. Runup heights of the waves were much less on the northwest and southwest sides of the islands, and no wave damage was incurred there. Locally, high-velocity currents that accompanied the waves caused intense erosion and redistribution of unconsolidated natural and artificial shore deposits and of shallow sea-floor deposits. The Alaska earthquake was the greatest natural catastrophe to befall the Kodiak Island area in historic time. The combination of seismic shock and the earthquake-related tectonic deformation and seismic sea waves took 18 lives, destroyed property worth about $45 million, and resulted in estimated losses of income to the fishing industry of an additional $5 million. Most of the damage and all of the loss of life were directly attributable to the seismic sea waves that crippled the city of Kodiak, wiped out the village of Kaguyak, and destroyed most of the village of Old Harbor and parts of the villages of Afognak and Uzinki. Bridges and segments of the highways in the vicinity of the city of Kodiak were washed out, and parts of the Kodiak Naval Station were inundated and damaged. Especially serious to all the damaged communities was the loss of fishing boats, seafood processing plants, and other waterfront installations, which had been the mainstay of the economy. Additional heavy losses resulted from the combined regional tectonic and local surficial subsidence that occurred during the earthquake. Widespread shoreline flooding by high tides necessitated raising, protecting, or removing many installations otherwise undamaged by the earthquake or waves. Structural damage attributable to seismic shock during the earthquake was relatively light and was restricted to areas underlain by saturated unconsolidated deposits. The chief structural failure in the area as a result of shaking was the collapse of part of a cannery built on saturated beach deposits that were partially liquefied during the earthquake. Minor structural damage resulted from differential settlement and cracking of the ground on natural granular deposits and artificial fills. The overwhelming majority of structures are constructed on indurated bedrock; none of these sustained damage other than small losses resulting from shifting about and breakage of their contents.

Alaska↗
USGS2013

Restoration potential of sedge meadows in hand-cultivated soybean fields in northeastern China

Sedge meadows can be difficult to restore from farmed fields if key structural dominants are missing from propagule banks. In hand-cultivated soybean fields in northeastern China, we asked if tussock-forming Carex and other wetland species were present as seed or asexual propagules. In the Sanjiang Plain, China, we compared the seed banks, vegetative propagules (below-ground) and standing vegetation of natural and restored sedge meadows, and hand-cultivated soybean fields in drained and flooded conditions. We found that important wetland species survived cultivation as seeds for some time (e.g. Calamogrostis angustifolia and Potamogeton crispus) and as field weeds (e.g. C. angustifolia and Phragmites australis). Key structural species were missing in these fields, for example, Carex meyeriana. We also observed that sedge meadows restored without planting or seeding lacked tussock-forming sedges. The structure of the seed bank was related to experimental water regime, and field environments of tussock height, thatch depth, and presence of burning as based on Nonmetric Multidimensional Scaling analysis. To re-establish the structure imposed by tussock sedges, specific technologies might be developed to encourage the development of tussocks in restored sedge meadows.

Sanjiang Plain↗
USGS2009

Decision Support System for Evaluation of Gunnison River Flow Regimes With Respect To Resources of the Black Canyon of the Gunnison National Park

This report describes and documents a decision support system for the Gunnison River in Black Canyon of the Gunnison National Park. It is a macro-embedded EXCEL program that calculates and displays indicators representing valued characteristics or processes in the Black Canyon based on daily flows of the Gunnison River. The program is designed to easily accept input from downloaded stream gage records or output from the RIVERWARE reservoir operations model being used for the upstream Aspinall Unit. The decision support system is structured to compare as many as eight alternative flow regimes, where each alternative is represented by a daily sequence of at least 20 calendar years of streamflow. Indicators include selected flow statistics, riparian plant community distribution, clearing of box elder by inundation and scour, several measures of sediment mobilization, trout fry habitat, and federal reserved water rights. Calculation of variables representing National Park Service federal reserved water rights requires additional secondary input files pertaining to forecast and actual basin inflows and storage levels in Blue Mesa reservoir. Example input files representing a range of situations including historical, reconstructed natural, and simulated alternative reservoir operations are provided with the software.

Open-File Report↗
USGS2001

Coastal change analysis program implemented in Louisiana

Landsat Thematic Mapper images from 1990 to 1996 and collateral data sources were used to classify the land cover of the Mermentau River Basin (MRB) within the Chenier Plain of coastal Louisiana. Landcover classes followed the definition of the National Oceanic and Atmospheric Administration's Coastal Change Analysis Program; however, classification methods had to be developed as part of this study for attainment of these national classification standards. Classification method developments were especially important when classes were spectrally inseparable, when classes were part of spatial and spectral continuums, when the spatial resolution of the sensor included more than one landcover type, and when human activities caused abnormal transitions in the landscape. Most classification problems were overcome by using one or a combination of techniques, such as separating the MRB into subregions of commonality, applying masks to specific land mixtures, and highlighting class transitions between years that were highly unlikely. Overall, 1990, 1993, and 1996 classification accuracy percentages (associated kappa statistics) were 80% (0.79), 78% (0.76), and 86% (0.84), respectively. Most classification errors were associated with confusion between managed (cultivated land) and unmanaged grassland classes; scrub shrub, grasslands and forest classes; water, unconsolidated shore and bare land classes; and especially in 1993, between water and floating vegetation classes. Combining cultivated land and grassland classes and water and floating vegetation classes into single classes accuracies for 1990, 1993, and 1996 increased to 82%, 83%, and 90%, respectively. To improve the interpretation of landcover change, three indicators of landcover class stability were formulated. Location stability was defined as the percentage of a landcover class that remained as the same class in the same location at the beginning and the end of the monitoring period. Residence stability was defined as the percent change in each class within the entire MRB during the monitoring period. Turnover was defined as the addition of other landcover classes to the target landcover class during the defined monitoring period. These indicators allowed quick assessment of the dynamic nature of landcover classes, both in reference to a spatial location and to retaining their presence throughout the MRB. Examining the landcover changes between 1990 to 1993 and 1993 to 1996, led us to five principal findings: (1) Landcover turnover is maintaining a near stable logging cycle, although the locations of grassland, scrub shrub, and forest areas involved in the cycle appeared to change. (2) Planting of seedlings is critical to maintaining cycle stability. (3) Logging activities tend to replace woody land mixed forests with woody land evergreen forests. (4) Wetland estuarine marshes are expanding slightly. (5) Wetland palustrine marshes and mature forested wetlands in the MRB are relatively stable.

Louisiana↗
USGS2021

Profiling lunar dust dissolution in aqueous environments: The design concept

Published studies and internal NASA reports indicate that when native lunar dust is suspended in an aqueous solution a variety of metal and other ions are released. This release has implications for future lunar missions, ranging from effects on mission hardware, effects on life support systems, possible direct effects on human health, and effects on research experiments such as plant growth experiments, space biology experiments and any activities that may involve the use of water sourced from the lunar poles. Furthermore, such contaminants could become concentrated or chemically altered to a more hazardous form during a variety of lunar mission activities, including everything from space suit cleaning to lunar industrial materials extraction. The exact profile of the release of ions from lunar dust and the nature of the partially dissolved particles has not been explored. Any model of this dissolution must be based on an understanding of the unique micromorphology of lunar dust, including its glassy nature, agglutinate features, high surface area and the presence of small deposits of elemental iron (nanophase iron) located near the surface of the grain particles. Dust has a very high surface area available for interaction with water. For this reason, on first exposure to water, an immediate pulsed release of ions could occur, with more prolonged release taking place over months or years. The few studies that have been conducted previously have been limited in both the time scales examined and in the selection of ions that were measured. The proposed investigation is a comprehensive materials science investigation, using the most modern analytical tools to catalogue all metals given off from lunar dust in various aqueous solutions and their time profiles of release from the very short term to the very long term. The product of the proposed study will be a comprehensive database determined from NASA curated samples collected from the Apollo landing sites that can be applied to research in both living systems and non-living systems on the moon. The methods developed in the proposed study will also establish standards for analysis of lunar dust samples returned from future manned missions (Artemis and others) and future robotic missions. The knowledge gained from this basic materials science investigation will have broad impact on the design of engineered human safety and health systems.

Acta Astronautica↗
USGS2000

The importance of ground water in the Great Lakes Region

Ground water is a major natural resource in the Great Lakes Region because it indirectly contributes more than 50 percent of the stream discharge to the Great Lakes. In addition, ground water is the source of drinking water for millions of people in the region, is an important source of supply for agriculture and many industries, and provides a relatively uniform supply of water in some ecologically sensitive areas to sustain plant and animal species. Therefore, to improve our understanding of water-resources issues in the Great Lakes Region, it is important to have a better understanding of the role that ground water plays in the overall hydrologic system of the lakes. The main ground-water resources issues in the Great Lakes Region are related to the amount of ground water, the interaction of ground water and surface water, changes in ground-water quality as development expands, and ecosystem health related to quantity and quality of water. Issues related to the amount of ground water Although the amount of water in the Great Lakes Region is vast, issues related to relatively small quantities of water are being raised more and more often. For example, even though the amount of ground water pumped in the region is small compared to the total amount of water present, ground water is an important source of public-water supply as well as an important source of supply for industrial, agricultural, and domestic needs. Less clearly understood, however, is the relation between the amount of streamflow discharging to the Great Lakes and the large portion of that flow that originates as ground water. The implications of this understanding for water- and land-use practices and, in turn, their effects on water quantity and quality, have not been fully incorporated into a policy framework. To help include information about the implications of the role that ground water plays in addressing regional water issues, a comprehensive analysis of indirect ground-water discharge to the Great Lakes is needed. Direct ground-water discharge to the Great Lakes is not a large factor in water-budget analyses for the Great Lakes. Locally, however, direct ground-water discharge to the Great Lakes may be important, even though the rates and places of discharge are not well known. A long-term evaluation of direct ground-water discharge to the Great Lakes would help place this hydrologic process in proper perspective. Near-shore areas with high rates of direct ground-water discharge may provide valuable habitat for aquatic organisms. Issues related to the interaction of ground water and surface water Withdrawal of ground water removes that water from the watershed when it is consumptively used or when the return flow is discharged to another drainage basin. Under these circumstances, pumping ground water constitutes a diversion of Great Lakes water. Alternatively, ground-water withdrawal could have the opposite effect of diverting ground-water flow into the watershed by altering the ground-water divides. In particular, as withdrawals associated with urban expansion increase, more accurate data on the amount and effects of ground-water use need to be collected. Data on the amounts of ground water pumped both within the watershed and outside, but near the watershed boundaries needs to be collected and evaluated for potential diversion of water to or from the Great Lakes. It is currently thought that both irrigation and ground-water withdrawals near the watershed boundaries constitute relatively small amounts of water; however, both rapidly changing farming practices and rapidly expanding urban communities could alter these amounts in a relatively short timeframe, especially during drought periods. At present, the effects of ground-water withdrawals have been quantified in detail at only a few urban locations. In addition to quantifying the amount of water pumped out of aquifers, it is also important to improve our knowledge of the amount of water that is recharging them. Ground-water recharge rates estimated in earlier studies cover only a small part of the Great Lakes Region. A comprehensive study of ground-water recharge rates for the entire watershed is needed to more completely determine the role of ground water in the hydrologic budget of the Great Lakes. Issues related to changes in ground-water quality as development expands Ground-water quality is as important as quantity for most water uses. As ground-water development proceeds, the possibility of altering the quality of ground water increases. The quality of ground water can be altered when water levels are drawn below the layer that confines the aquifer or by inducing water of lesser quality into an aquifer. Many local studies of these problems have been conducted, but few regional-scale analyses of changes in ground-water quality as a result of ground-water development have been done. Issues related to ecosystem health and quantity and quality of ground water Ground water is essential to maintain wetlands and to provide healthy habitat for other aquatic systems. Wetland hydrology is widely recognized as the primary influence on wetland ecology, development, and persistence, and information about hydrology is essential to understanding and quantifying wetland functions and processes. Studies of the role of ground water in selected wetlands in a range of physiographic settings throughout the Great Lakes watershed are needed to more fully understand the role of wetlands in the Great Lakes Region.

Lake Erie, Lake Huron, Lake Michigan, Lake Ontario↗
USGS2013

Estimating riparian and agricultural evapotranspiration by reference crop evapotranspiration and MODIS Enhanced Vegetation Index

Dryland river basins frequently support both irrigated agriculture and riparian vegetation and remote sensing methods are needed to monitor water use by both crops and natural vegetation in irrigation districts. We developed an algorithm for estimating actual evapotranspiration (ET a ) based on the Enhanced Vegetation Index (EVI) from the Moderate Resolution Imaging Spectrometer (MODIS) sensor on the EOS-1 Terra satellite and locally-derived measurements of reference crop ET (ET o ). The algorithm was calibrated with five years of ETa data from three eddy covariance flux towers set in riparian plant associations on the upper San Pedro River, Arizona, supplemented with ETa data for alfalfa and cotton from the literature. The algorithm was based on an equation of the form ET a = ET o [a(1 − e −bEVI ) − c], where the term (1 − e −bEVI ) is derived from the Beer-Lambert Law to express light absorption by a canopy, with EVI replacing leaf area index as an estimate of the density of light-absorbing units. The resulting algorithm capably predicted ET a across riparian plants and crops (r 2 = 0.73). It was then tested against water balance data for five irrigation districts and flux tower data for two riparian zones for which season-long or multi-year ET a data were available. Predictions were within 10% of measured results in each case, with a non-significant (P = 0.89) difference between mean measured and modeled ET a of 5.4% over all validation sites. Validation and calibration data sets were combined to present a final predictive equation for application across crops and riparian plant associations for monitoring individual irrigation districts or for conducting global water use assessments of mixed agricultural and riparian biomes.

Remote Sensing↗
USGS1990

Soil-vegetation correlations in the Connecticut River floodplain of Western Massachusetts

As part of a national study analyzing the relation between hydric soils and wetland vegetation, the vegetation associated with a series of known soils was sampled along the Connecticut River floodplain in Massachusetts. Weighted average and index average (presence/absence) values were calculated for vegetation using wetland ecological index values from the National List of Plant Species that Occur in Wetlands developed by the U.S. Fish and Wildlife Service and procedures developed by T. R. Wentworth and G. P. Johnson at North Carolina State University. Good correspondence between soils and vegetation was recorded with two exceptions. Two typically nonhydric soils were determined to be hydric based on vegetation analyses. Examination of the groundwater hydrology of these two soils confirmed their hydric nature. The authors suggested that one of these soils may need to be redefined and they also suggested that the assigned index values for a few species of vegetation should be reexamined. However, in general the index average values of vegetation based on published wetland index values corresponded with the hydric and nonhydric nature of soils.

Massachusetts↗
USGS2019

Management opportunities and research priorities for Great Plains grasslands

The Great Plains Grassland Summit: Challenges and Opportunities from North to South was held April 10-11, 2018 in Denver, Colorado. The geographical focus for the summit was the entire Great Plains. The summit was designed to provide syntheses of information about key grassland topics of interest in the Great Plains; networking and learning channels for managers, researchers and stakeholders; and working sessions for sharing input and ideas about challenges and future research and management opportunities. The summit was convened to better understand Great Plains stressors and resource demands and how to manage them, and to discuss methods for improved collaboration among natural resource managers, scientists, and stakeholders. Over 200 stakeholders, who collectively were affiliated with all of the Great Plains states, attended the summit. Attendees included university researchers, government scientists, and individuals affiliated with federal and state agencies, tribes, the private sector, and non-governmental organizations (NGOs). Plenary speakers provided syntheses of current knowledge on key topics to help stage working sessions on working lands, native plants and pollinators, native wildlife and biological diversity, invasive species, wildland and prescribed fire, energy development, and weather, water, and climate. The summit steering committee designed one suite of questions that were asked of participants in each working session. This report is a digest of the input from those who attended the seven working sessions and responded to the structured questions.

Colorado, Illinois, Iowa, Kansas, Minnesota, Misso↗
USGS2021

Is the grass always greener? Land surface phenology reveals differences in peak and season-long vegetation productivity responses to climate and management

Vegetation phenology—the seasonal timing and duration of vegetative phases—is controlled by spatiotemporally variable contributions of climatic and environmental factors plus additional potential influence from human management. We used land surface phenology derived from the Advanced Very High Resolution Radiometer and climate data to examine variability in vegetation productivity and phenological dates from 1989 to 2014 in the U.S. Northwestern Plains, a region with notable spatial heterogeneity in climate, vegetation, and land use. We first analyzed interannual trends in six phenological measures as a baseline. We then demonstrated how including annual-resolution predictors can provide more nuanced insights into measures of phenology between plant communities and across the ecoregion. Across the study area, higher annual precipitation increased both peak and season-long productivity. In contrast, higher mean annual temperatures tended to increase peak productivity but for the majority of the study area decreased season-long productivity. Annual precipitation and temperature had strong explanatory power for productivity-related phenology measures but predicted date-based measures poorly. We found that relationships between climate and phenology varied across the region and among plant communities and that factors such as recovery from disturbance and anthropogenic management also contributed in certain regions. In sum, phenological measures did not respond ubiquitously nor covary in their responses. Nonclimatic dynamics can decouple phenology from climate; therefore, analyses including only interannual trends should not assume climate alone drives patterns. For example, models of areas exhibiting greening or browning should account for climate, anthropogenic influence, and natural disturbances. Investigating multiple aspects of phenology to describe growing-season dynamics provides a richer understanding of spatiotemporal patterns that can be used for predicting ecosystem responses to future climates and land-use change. Such understanding allows for clearer interpretation of results for conservation, wildlife, and land management.

Ecology and Evolution↗
USGS2016

The role of natural biogeochemical barriers in limiting metal loading to a stream affected by mine drainage

Rio San Giorgio (Iglesiente, Sardinia, Italy), a stream affected by abandoned mine wastes, is characterized by dense vegetation in the streambed, mainly comprised of Phragmites australis and Juncus acutus . This vegetation creates natural biogeochemical barriers that drive mineralization processes and attenuate metals load in the stream. Several techniques, covering scales from micrometres to kilometres, were applied to investigate the biogeochemical processes: water chemistry, injected hydrologic tracer, mineralogy, microscopic investigation and X-ray spectroscopy. From this multiscale and multimethod approach, we recognized two predominant sets of biogeochemical processes: microbially driven metal sulphide precipitation, mainly resulting in pyrite formation; and plant uptake of metals that leads to formation of iron oxide-hydroxide and incorporation of Zn within the roots and aerial part (stem and leaves). The dense vegetation in the Rio San Giorgio streambed controls its morphology, velocity of streamflow, and, as reflected by observed bromide-tracer loss, enhanced water exchange between the streambed and the hyporheic zone. The combined effect of these vegetative controls is to establish biogeochemical barriers that greatly retard trace-metal mobility in the hyporheic zone. We estimated this effect can lead to an apparent decrease in Zn load up to 60%.

Iglesias↗
USGS2023

Roles of climatic and anthropogenic factors in shaping Holocene vegetation and fire regimes in Great Dismal Swamp, eastern USA

The Great Dismal Swamp wetland, spanning >400 km 2 along the Virginia and North Carolina border, was shaped by a complex combination of geomorphic, climatic, and anthropogenic forcings during the last 14,000 years. Pollen, macrofossils, charcoal, and physical properties from sediment cores at seven sites provide a detailed record of the spatial heterogeneity of the wetland and the roles played by natural hydrologic variability, wildfire, and human modification of drainage in shaping vegetation and habitats. Cold-temperate forests occupied regional uplands from at least 13.5–10.3 cal ka BP. Marshes dominated by grasses and other herbaceous taxa began developing along low-elevation streams as early as 10.3 cal ka BP, resulting in accumulation of organic silts. Long-hydroperiod, peat accumulating marshes, with abundant floating aquatic plants, developed as early as 9.6 cal ka BP, as rapid rates of sea-level rise elevated the water table and facilitated wetland development and peat accumulation along stream courses. By the mid-Holocene (c. 7–6.5 cal ka BP), when local sea-level rise began slowing and reached about 12–15 m below present, shorter hydroperiod, peat-accumulating marshes dominated the landscape, with increased wildfire activity. Great Dismal Swamp vegetation shifted from marshes to peat-accumulating forested wetlands by c. 3.7 cal ka BP; these were dominated by varying combinations of Nyssa (tupelo), Taxodium (cypress), and Chamaecyparis thyoides (Atlantic white cedar). Wildfires were infrequent during this time, and the forested wetlands persisted, with minor compositional changes related to climate-driven fluctuations in stream flow, until colonial ditching and logging began in the swamp during the late 18th century. These activities decreased cypress and cedar populations, and, by the mid-20th century, expanded ditching resulted in even drier conditions and expansion of maple-gum (dominated by Acer and Liquidambar ) , and pine-pocosin (dominated by Pinus ) forests. The distribution of these forests differs from that of the late Holocene and represents a fundamental shift in hydrology, peat structure, vegetation, and fire regime due to landscape alterations of the last few centuries.

North Carolina, Virginia↗
USGS2024

Grassland Effectiveness Monitoring (GEM): A tiered approach for habitat treatment assessment across private lands incentive programs

Introduction The decline of North American grasslands is a topic of increasing interest as agencies and organizations work to address subsequent declines in wildlife species, including grassland birds (Rosenberg et al. 2019), pronghorn (Antilocapra americana) (Gedir et al. 2015), and other grassland-dependent taxa. In response to grassland habitat loss, conservation programs and policies have been developed to provide biologists and landowners mechanisms to restore grassland habitat on private lands. These range from federal programs such as the U.S. Fish and Wildlife Service’s (USFWS) Partners for Fish and Wildlife program (PFW) and the Natural Resources Conservation Service’s (NRCS) Environmental Quality Incentive Program, state programs such as Texas Parks and Wildlife Department’s Pastures for Upland Birds, and partnership-based programs such as the Oaks and Prairies Joint Venture’s Grassland Restoration Incentive Program (GRIP). When managing and restoring grassland habitat, these programs typically utilize the same set of practices: prescribed grazing, prescribed fire, herbicide, brush management, and range planting. To restore grasslands at scale, large sums of funding have been invested into these programs. For example, approximately $1 million is spent by PFW in Texas annually (D. Wilhelm, USFWS, personal communication). However, it is rare for these conservation programs to have associated monitoring efforts that are consistently used to assess the effectiveness of the aforementioned practices in achieving program and project objectives. As such, it is difficult to communicate to funders and the public whether these conservation programs are successfully addressing grassland decline. Similar objectives and practices across programs, however, provide a unique opportunity for developing an innovative monitoring methodology that focuses on providing a collaborative solution to this dilemma. Our objective is to develop a grassland monitoring program that can be used across agencies, organizations, and conservation programs to assess the effectiveness of practices and programs in restoring healthy grasslands. In addition, we seek to develop a program that maintains consistency to allow for regional to national-scale reporting while also allowing flexibility for achieving local and partner monitoring objectives. Our vision is for this program to be used across North American grasslands to improve our ability to address the questions: “Is it actually working?” and “How can we improve habitat delivery?”

Conference Paper↗
USGS2025

Assessing diet and genotyping success of goat pellet surveys from 2019 in Glacier National Park

Fecal pellets contain genetic information and can be used to identify individuals, their diet, and more. Individual identification can be useful in understanding movements of individuals, developing population estimates, assessing vital rates, genetic diversity and structure, and evaluating trends over time (e.g., Epps et al 2024). Successful genotyping depends on the quality of the sample, which can be influenced by many things including the initial state of the sample, environmental conditions that the pellets were exposed to, and the method of storage. The diet of mountain goats ( Oreamnos americanus ) is hard to study as they are habitat specialists in some of the most remote and rugged alpine environments (Festa-Bianchet & Côté 2012). These iconic ungulates epitomize the renowned wilderness character of Glacier National Park (GNP), yet the population has declined by 45% since 2008 likely due at least in part to changing climate (Graves et al. 2025). This is well above the International Union for the Conservation of Nature’s population decline criterion used to designate a species as vulnerable (IUCN 2012). Mountain goats are known as dietary generalists employing highly variable diets across systems, but diets have not been identified for GNP. Identifying goat diet composition in GNP can provide the information needed to determine whether this population decline could be related to climate-change induced shifts in forage phenology, diversity, productivity, and plant community structure. Other anthropogenic changes in GNP, such as increases in exotic and invasive plant species, will continue to affect plant community composition (Lesica et al. 1993). These alterations may reduce optimal forage availability and quality, which could have a deleterious effect on mountain goat survival. To examine these possibilities, we must first ask- What precisely are the mountain goats of Glacier National Park eating? DNA metabarcoding of fecal pellets provides a cutting-edge, non-invasive method for assessing herbivore diet. Previous studies of mountain goat diet have used methods such as fecal crude protein analysis (Festa-Bianchet & Côté 2012), rumen analysis (Saunders 1955), fecal microhistology (Cobb et al. 2012), and bite-for-bite feeding observations (Daily et al. 1984). Many of these studies have only been able to identify diet components to functional plant type and the methods used are biased towards less digestible diet components such as grasses (McInnis et al. 1983). Metabarcoding of fecal pellets can provide a higher taxonomic resolution than previous methods (Scasta et al. 2019, Stapleton et al. 2022) and open the field for increased participation of volunteers, also called community or citizen scientists. Here, we use mountain goat fecal pellets to conduct 1) an evaluation of which conditions might influence genotyping success and 2) a preliminary assessment of diet using metabarcoding. This pilot study allowed us to evaluate which pellets to focus on collecting, identify the best storage methods, explore approaches for analyzing metabarcoding data, examine the utility of metabarcoding for acquiring taxonomically specific diet information, and to identify genetic sequences that could not be resolved to genus or species levels using these methods. We examined the frequency of occurrence and relative diet composition of identified forbs, shrubs, graminoids, mosses, and trees in mountain goat diets.

Montana↗