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N.H. Euliss

Publications and source records attributed to N.H. Euliss.

At least 19 recordsLinked to original sources
USGS2011

Prototyping an online wetland ecosystem services model using open model sharing standards

Great interest currently exists for developing ecosystem models to forecast how ecosystem services may change under alternative land use and climate futures. Ecosystem services are diverse and include supporting services or functions (e.g., primary production, nutrient cycling), provisioning services (e.g., wildlife, groundwater), regulating services (e.g., water purification, floodwater retention), and even cultural services (e.g., ecotourism, cultural heritage). Hence, the knowledge base necessary to quantify ecosystem services is broad and derived from many diverse scientific disciplines. Building the required interdisciplinary models is especially challenging as modelers from different locations and times may develop the disciplinary models needed for ecosystem simulations, and these models must be identified and made accessible to the interdisciplinary simulation. Additional difficulties include inconsistent data structures, formats, and metadata required by geospatial models as well as limitations on computing, storage, and connectivity. Traditional standalone and closed network systems cannot fully support sharing and integrating interdisciplinary geospatial models from variant sources. To address this need, we developed an approach to openly share and access geospatial computational models using distributed Geographic Information System (GIS) techniques and open geospatial standards. We included a means to share computational models compliant with Open Geospatial Consortium (OGC) Web Processing Services (WPS) standard to ensure modelers have an efficient and simplified means to publish new models. To demonstrate our approach, we developed five disciplinary models that can be integrated and shared to simulate a few of the ecosystem services (e.g., water storage, waterfowl breeding) that are provided by wetlands in the Prairie Pothole Region (PPR) of North America.

Environmental Modelling and Software↗
USGS2009

Greenhouse gas flux from cropland and restored wetlands in the Prairie Pothole Region

It has been well documented that restored wetlands in the Prairie Pothole Region of North America do store carbon. However, the net benefit of carbon sequestration in wetlands in terms of a reduction in global warming forcing has often been questioned because of potentially greater emissions of greenhouse gases (GHGs) such as nitrous oxide (N 2 O) and methane (CH 4 ). We compared gas emissions (N 2 O, CH 4 , carbon dioxide [CO 2 ]) and soil moisture and temperature from eight cropland and eight restored grassland wetlands in the Prairie Pothole Region from May to October, 2003, to better understand the atmospheric carbon mitigation potential of restored wetlands. Results show that carbon dioxide contributed the most (90%) to net-GHG flux, followed by CH 4 (9%) and N 2 O (1%). Fluxes of N 2 O, CH 4 , CO 2 , and their combined global warming potential (CO 2 equivalents) did not significantly differ between cropland and grassland wetlands. The seasonal pattern in flux was similar in cropland and grassland wetlands with peak emissions of N 2 O and CH 4 occurring when soil water-filled pore space (WFPS) was 40-60% and >60%, respectively; negative CH 4 fluxes were observed when WFPS approached 40%. Negative CH 4 fluxes from grassland wetlands occurred earlier in the season and were more pronounced than those from cropland sites because WFPS declined more rapidly in grassland wetlands; this decline was likely due to higher infiltration and evapotranspiration rates associated with grasslands. Our results suggest that restoring cropland wetlands does not result in greater emissions of N 2 O and CH 4 , and therefore would not offset potential soil carbon sequestration. These findings, however, are limited to a small sample of seasonal wetlands with relatively short hydroperiods. A more comprehensive assessment of the GHG mitigation potential of restored wetlands should include a diversity of wetland types and land-use practices and consider the impact of variable climatic cycles that affect wetland hydrology.

Soil Biology and Biochemistry↗
USGS2008

Application of a geomorphic and temporal perspective to wetland management in North America

The failure of managed wetlands to provide a broad suite of ecosystem services (e.g., carbon storage, wildlife habitat, ground-water recharge, storm-water retention) valuable to society is primarily the result of a lack of consideration of ecosystem processes that maintain productive wetland ecosystems or physical and social forces that restrict a manager's ability to apply actions that allow those processes to occur. Therefore, we outline a course of action that considers restoration of ecosystem processes in those systems where off-site land use or physical alterations restrict local management. Upon considering a wetland system, or examining a particular management regime, there are several factors that will allow successful restoration of wetland services. An initial step is examination of the political/social factors that have structured the current ecological condition and whether those realities can be addressed. Most successful restorations of wetland ecosystem services involve cooperation among multiple agencies, acquisition of funds from non-traditional sources, seeking of scientific advice on ecosystem processes, and cultivation of good working relationships among biologists, managers, and maintenance staff. Beyond that, in on-site wetland situations, management should examine the existing hydrogeomorphic situation and processes (e.g., climatic variation, tides, riverine flood-pulse events) responsible for maintenance of ecosystem services within a given temporal framework appropriate for that wetland's hydrologic pattern. We discuss these processes for five major wetland types (depressional, lacustrine, estuarine, riverine, and man-made impoundments) and then provide two case histories in which this approach was applied: Seney National Wildlife Refuge with a restored fen system and Bosque del Apache National Wildlife Refuge where riverine processes have been simulated to restore native habitat. With adequate partnerships and administrative and political support, managers faced with degraded and/or disconnected wetland processes will be able to restore ecosystem services for society in our highly altered landscape by considering wetlands in their given hydrogeomorphic setting and temporal stage. ?? 2008 The Society of Wetland Scientists.

Wetlands↗
USGS2006

North American prairie wetlands are important nonforested land-based carbon storage sites

We evaluated the potential of prairie wetlands in North America as carbon sinks. Agricultural conversion has resulted in the average loss of 10.1 Mg ha- 1 of soil organic carbon on over 16 million ha of wetlands in this region. Wetland restoration has potential to sequester 378 Tg of organic carbon over a 10-year period. Wetlands can sequester over twice the organic carbon as no-till cropland on only about 17% of the total land area in the region. We estimate that wetland restoration has potential to offset 2.4% of the annual fossil CO2 emission reported for North America in 1990. ?? 2005 Elsevier B.V. All rights reserved.

Science of the Total Environment↗
USGS2005

Biotic interactions as determinants of ecosystem structure in prairie wetlands: An example using fish

Wetlands are abundant throughout the prairie pothole region (PPR), an area comprising over 700,000 km2 in central North America. Prairie wetland communities are strongly influenced by regional physiography and climate, resulting in extreme spatial and temporal variability relative to other aquatic ecosystems. Given the strong influence of abiotic factors, PPR wetland communities have been viewed traditionally in the context of their responses to chemical and physical features of landscape and climate. Although useful, this physical-chemical paradigm may fail to account for ecosystem variability due to biotic influences, particularly those associated with presence of fish. Spatial and temporal variability in fish populations, in turn, may reflect anthropogenic activities, landscape characteristics, and climate-mediated effects on water levels, surface connectivity, and hydroperiods. We reviewed studies assessing influences of fish on prairie wetlands and examined precipitation patterns and biological data from PPR wetlands in east-central North Dakota and western Minnesota, USA. Our review and analysis indicated that native fish influence many characteristics of permanently flooded prairie wetlands, including water clarity and abundance of phytoplankton, submerged macrophytes, and aquatic invertebrates. We suggest that ecologists and managers will benefit from conceptual paradigms that better meld biotic interactions associated with fish, and perhaps other organisms, with chemical and physical influences on prairie wetland communities. ?? 2005, The Society of Wetland Scientists.

Wetlands↗
USGS2004

The wetland continuum: A conceptual framework for interpreting biological studies

We describe a conceptual model, the wetland continuum, which allows wetland managers, scientists, and ecologists to consider simultaneously the influence of climate and hydrologic setting on wetland biological communities. Although multidimensional, the wetland continuum is most easily represented as a two-dimensional gradient, with ground water and atmospheric water constituting the horizontal and vertical axis, respectively. By locating the position of a wetland on both axes of the continuum, the potential biological expression of the wetland can be predicted at any point in time. The model provides a framework useful in the organization and interpretation of biological data from wetlands by incorporating the dynamic changes these systems undergo as a result of normal climatic variation rather than placing them into static categories common to many wetland classification systems. While we developed this model from the literature available for depressional wetlands in the prairie pothole region of North America, we believe the concept has application to wetlands in many other geographic locations.

Wetlands↗
USGS2004

Invertebrate egg banks of restored, natural, and drained wetlands in the Prairie Pothole Region of the United States

Analogous to ‘seed banks,’ ‘egg banks’ are important for seasonal succession and maintenance of invertebrate species diversity throughout wet and dry cycles in the prairie pothole region. Further, recruitment of invertebrates from relic egg banks in the sediments and dispersal of eggs into wetlands is believed to be important for reestablishment of invertebrates in recently restored wetlands. Alhough tens-ofthousands of wetlands have been restored in the prairie pothole region of the United States, studies have not been conducted to evaluate the recovery of invertebrate egg banks in restored wetlands. We used taxon richness and abundance as indicators of potential egg bank recovery and compared these parameters in restored wetlands to those of non-drained and drained wetlands with a history of cultivation and also to reference wetlands with no history of cultivation. We found few significant differences among wetland categories within three physiographic regions (Glaciated Plains, Missouri Coteau, and Prairie Coteau). Most statistical comparisons indicated that restored wetlands had invertebrate egg banks similar to reference, nondrained, and drained wetlands. The one exception was drained seasonal wetlands in the Glaciated Plains, which had significantly lower taxon richness and invertebrate abundance than the other wetland categories. Trends did suggest that invertebrate egg bank taxon richness and abundance are increasing in restored seasonal wetlands relative to their drained analogues, whereas a similar trend was not observed for restored semi-permanent wetlands. Although recovery was not related to years since restoration, comparisons of restored wetlands with reference wetlands suggest that recovery potential may be inversely related to the extent of wetland drainage and intensive agriculture that varies spatially in the prairie pothole region. Our research suggests that periodic drawdowns of semi-permanent restored wetlands may be needed to promote production and development of invertebrate egg banks. Inoculation of restored wetlands may also be needed in areas where extensive wetland drainage has resulted in fewer wetland habitats to provide sources of passively dispersed eggs to newly restored wetlands.

Iowa, Minnesota, Montana, North Dakota, South Dako↗
USGS2004

The flora of the Cottonwood Lake Study Area, Stutsman County, North Dakota

The 92 ha Cottonwood Lake Study Area is located in south-central North Dakota along the eastern edge of a glacial stagnation moraine known as the Missouri Coteau. The study area has been the focus of biologic and hydrologic research since the U.S. Fish and Wildlife Service purchased the site in 1963. We studied the plant communities of the Cottonwood Lake Study Area from 1992 to 2001. During this time period, the vascular flora of the study area consisted of 220 species representing 51 families. Over half of the species were perennial forbs (117 species). Perennial grasses (26 species) and annual forbs (22 species) made up the next two largest physiognomic groupings. The flora, having a mean Coefficient of Conservatism of 4.6 and a Floristic Quality Index of 62, consisted of 187 native species. Thirty-three species were non-natives. Our annotated list should provide information useful to researchers, graduate students, and others as they design and implement future studies in wetlands and uplands both in and around the Cottonwood Lake Study Area.

Prairie Naturalist↗
USGS2003

Effects of sediment load on emergence of aquatic invertebrates and plants from wetland soil egg and seed banks

Intensive agricultural activities near prairie wetlands may result in excessive sediment loads, which may bury seed and invertebrate egg banks that are important for maintenance and cycling of biotic communities during wet/dry cycles. Sediment-load experiments indicated that burial depths of 0.5 cm caused a 91.7% reduction in total seedling emergence and a 99.7% reduction in total invertebrate emergence. These results suggest sediment entering wetlands from agricultural erosion may hamper successional changes throughout interannual climate cycles.

Wetlands↗
USGS2003

Sedimentation rates in the marshes of Sand Lake National Wildlife Refuge

Impoundments located within river systems in the Northern Great Plains are vulnerable to sediment inputs because intensive agriculture in watersheds has increased soil erosion and sediments in rivers. At the request of the U.S. Fish and Wildlife Service (FWS), we evaluated the vertical accretion of sediment in the Mud Lake impoundment of Sand Lake National Wildlife Refuge (NWR), Brown County, South Dakota. The Mud Lake impoundment was created in 1936 by constructing a low-head dam across the James River. We collected sediment cores from the Mud Lake impoundment during August 2000 for determination of vertical accretion rates. Accretion rates were estimated using cesium-13 7 and lead-210 isotopic dating techniques to estimate sediment accretion over the past 100 years. Accretion rates were greatest near the dam (1.3 cm yr-1) with less accretion (0.2 cm yr-1) occurring in the upper reaches of Mud Lake. As expected, accretion was highest near the dam where water velocities and greater water depth facilitates sediment deposition. Higher rates of sedimentation (accretion> 2.0 cm year-1) occurred during the 1990s when river flows were especially high. Since 1959, sediment accretion has reduced maximum pool depth of Mud Lake near the dam by 55 cm. Assuming that sediment accretion rates remain the same in the future, we project Mud Lake will have a maximum pool depth of 77 and 51 cm by 2020 and 2040, respectively. Over this same time frame, water depths in the upper reaches of Mud Lake would be reduced to< 2 cm. Projected future loss of water depth will severely limit the ability of managers to manipulate pool levels in Mud Lake to cycle vegetation and create interspersion of cover and water to meet current wildlife habitat management objectives. As predicted for major dams constructed on rivers throughout the world, Mud Lake will have a finite life span. Our data suggests that the functional life span of Mud Lake since construction will be < 100 years. We anticipate that over the next 20 years, sediments entering Mud Lake will reduce water depths to the point that current wildlife management objectives cannot be achieved through customary water-level manipulations. Sedimentation impacts are not unique to the Sand Lake NWR. It is widely accepted that impoundments trap sediments and shallow impoundments, such as those managed by the FWS, are especially vulnerable. Given the ecological impacts associated with loss of water depths, we recommend that managers begin evaluating the long-term wildlife management goals for the refuge relative to associated costs and feasibility of options available to enhance and maximize the life span of existing impoundments, including upper watershed management.

Report↗