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Research about Midwest

Source-linked reports with geographic coverage including Midwest.

15 recordsLinked to original sources
USGS2026

Connecting and coordinating conservation action across landscapes through regional planning processes and syntheses

Modern threats to conservation are often global; however, relevant conservation decisions and actions typically occur within local jurisdictions. The socio-ecological complexity of these problems requires collaboration across large landscapes, diverse community interests, and geopolitical boundaries, yet a lack of interoperability of planning products among decision makers, jurisdictions, and objectives impedes collaboration. Here, we provide a working model for the collaborative, iterative development of a landscape conservation design (LCD) in the Midwest region of the United States, the Midwest Conservation Blueprint, and demonstrate its applicability to the coordination of voluntary conservation actions and investments across jurisdictional boundaries. We used spatial prioritization software to synthesize over 20 datasets to develop a basemap of priority lands and waters for conservation across a diverse set of societal and ecological values (e.g., water quality, biodiversity, recreation). The Midwest Conservation Blueprint is a living plan, updated annually based on improvements in underlying data, understanding of local conditions, and public input. Landscape-scale planning is not designed to replace local knowledge or supersede decision-making authorities. However, by synthesizing existing data that represent diverse socio-ecological values and planning at a broader scale, the Midwest Conservation Blueprint documents where there are shared priorities and opportunities for collaborative landscape conservation.

Midwest↗
USGS2025

Effects of climate change on midwestern ecosystems: Appalachian – Interior – Northeast Mesic Forest

The Appalachian-Interior-Northeast Mesic Forest ecosystem, historically buffered by cool, moist conditions, may experience significant stress under future climate change, particularly due to intensifying droughts and milder winters in the midwestern United States. Droughts are expected to intensify in frequency and severity, depleting soil moisture, increasing tree mortality, and reshaping species composition. Increasing aridity and disrupted hydrologic cycles will likely accelerate soil erosion, deplete nutrients, and heighten wildfire risk. Meanwhile, milder winters may reduce snowpack insulation, increase freeze-thaw cycles, and alter growing seasons, potentially amplifying cold stress, disrupting phenology, and contributing to shifts in habitat structure and community composition. While easing winter severity may temporarily boost plant productivity and facilitate species migration into and throughout the Midwest, it can also increase the risk of frost damage for early-leafing trees and disrupt ecological relationships, such as plant-pollinator interactions. Together, these stressors may drive fundamental shifts in habitat structure and community composition, favoring drought-, fire-, and cold-tolerant species, while historically dominant, moisture-dependent species decline. Species with limited drought resistance, such as those with shallow roots or low water-use efficiency, may be especially vulnerable, while drought-adapted taxa could gain a competitive advantage. This shift could trigger a departure from over a century of mesophication in the Appalachian-Interior-Northeast Mesic Forest, which has favored shade-loving, moisture-dependent species in fire-suppressed landscapes. As a result, these forests may be particularly ill-equipped to withstand the novel environmental conditions imposed by intensifying droughts and milder winters. The Appalachian-Northeast Mesic Forest habitat group, dominated by eastern hemlock ( Tsuga canadensis ) and eastern white pine ( Pinus strobus ), is likely particularly vulnerable, as both dominant species are projected to decline due to increasing drought stress and shifting competitive dynamics. In the North-Central Beech - Maple - Basswood Forest, the Driftless Area of Wisconsin, Minnesota, and Iowa may be more vulnerable than more eastern portions of the habitat due to its already drier conditions, with climate change expected to push these communities beyond favorable conditions. Species interactions, including invasive species, pests, and herbivory, are also likely to be reshaped by climate change, compounding stress on habitat groups throughout the Appalachian-Interior-Northeast Mesic Forest. Warmer winters and increased disturbance may facilitate the expansion of invasive species, which outcompete native vegetation and alter ecosystem dynamics. At the same time, pests and pathogens are likely to become more destructive, as milder winters enhance their survival and spread and drought weakens tree defenses. Additionally, rising white-tailed deer ( Odocoileus virginianus ) populations, supported by warmer winters, may shift forest regeneration patterns by selectively browsing on sensitive seedlings and saplings, limiting the recruitment of historically dominant tree species while favoring browse-resistant plants. Collectively, these pressures can drive significant and ongoing ecological transformation in the Appalachian-Interior-Northeast Mesic Forest, highlighting the need for adaptive management strategies to sustain biodiversity and ecosystem function.

Illinois, Indiana, Iowa, Michigan, Minnesota, Miss↗
USGS2023

Flood-frequency analysis in the Midwest: Addressing potential nonstationarity of annual peak-flow records

Flood-frequency analysis is essential in numerous water-resource management applications, including critical structure design and flood-plain mapping. A basic assumption within Bulletin 17C [1], the standardized guidelines for conducting flood-frequency analysis, is that basins without major hydrologic alterations, such as regulation or urbanization, exhibit stationary statistical properties of the distribution of annual peak streamflow. That is, the mean, variance, and skew are constant over time and the peak-flow record is a representative sample of the population of future floods [1]. In recent decades, better understanding of long-term climatic persistence and concerns about climate and land-use change have caused the assumption of stationarity in peak-flow records to be reexamined [2, 3, 4, 5]. Under nonstationary conditions, the long-term distributional properties (mean, variance, and/or skew) of peak-flow series change one or more times, either gradually or abruptly. Nonstationarities may be attributed to one source, but are often a result of a mixture of drivers, making detection and attribution of nonstationarities challenging [6, 7, 8]. Failure to incorporate observed trends and abrupt changes into flood-frequency analysis may result in a poor representation of the true flood risk. Bulletin 17C currently offers no guidance on how to account for nonstationarities when estimating floods and acknowledges the benefit additional flood frequency studies that incorporate changing climate or basin characteristics into the analysis would provide[1].

Midwest↗
USGS2019

Invasive silver carp may compete with unionid mussels for algae: First experimental evidence

1. Unionid mussels are imperiled throughout the United States, where their global diversity is highest. Silver carp (Hypophthalmichthys molitrix Valenciennes in Cuvier & Valenciennes, 1844), an invasive planktivorous fish, has spread throughout Midwestern rivers and currently threatens the Great Lakes. Because silver carp remove plankton and other particles from the water column, they may compete with mussels for food resources. This would be among the first examples of a direct competitive interaction between fish and mussels. 2. To examine the potential for competition, a 30-d tank experiment was performed with 2-yr old fatmucket mussels (Lampsilis siliquoidea Barnes, 1823) and age-1 silver carp in three treatments: fatmucket only, silver carp only, and fatmucket + silver carp. All tanks were given a commercial algal-based diet daily and dry mass of suspended particles (an estimate of available food) and NH4, NO3, and NO2 concentrations were quantified every 5 d to track food availability and changes in nutrients. Initial and final silver carp total length (mm) and mass (g), and fatmucket length (mm), height (mm), and surface area (mm2) were measured. 3. Survival was 100% over the test duration for both species. Fatmucket grew less in the fatmucket + silver carp treatment, while silver carp growth was low regardless of treatment. Fatmucket also exhibited increased movement in the presence of silver carp. Suspended particles did not differ among treatments. Dissolved nitrogen concentrations were higher in the silver carp treatments, suggesting that silver carp increase nutrient availability in aquatic systems. 4. Overall, the slower growth rates observed in the fatmucket + silver carp treatment compared to the mussel only treatment suggest exploitative competition between invasive planktivorous silver carp and fatmucket and this competition could contribute to additional stress on already imperiled mussels.

Midwest↗
USGS2018

Relative importance of water-quality stressors in predicting fish community responses in midwestern streams

Fish, habitat, and water chemistry data were collected from 98 streams in the midwestern United States, an area dominated by intense cultivation of row crops, in order to identify important water‐quality stressors to fish communities. We focused on 10 stressors including riparian disturbance, riparian vegetative cover, instream fish cover, streambed sedimentation, streamflow variability, total nitrogen, total phosphorus, minimum dissolved oxygen, pesticides, and bed sediment contaminants. Fish community response variables included a measure of observed/expected taxonomic completeness; species‐specific tolerances to nitrogen, phosphorus, dissolved oxygen, and water temperature; the percent of species classified as macrohabitat generalists; and an index of pesticide toxicity to fish. Multivariate analysis indicated that total nitrogen was the most important stressor, signifying that fish communities were responding to total nitrogen despite relatively high levels common to an agricultural setting. Individually, fish taxonomic completeness decreased with increasing streambed sedimentation, whereas fish community tolerance to total phosphorus increased with increasing streambed sedimentation, riparian disturbance, and total nitrogen. These findings underscore the importance of multiple biological response metrics to better understand the effects of water‐quality stressors on fish communities and highlight the complex relations between total phosphorus and fish communities.

Midwest↗
USGS2016

Prediction of pesticide toxicity in Midwest streams

The occurrence of pesticide mixtures is common in stream waters of the United States, and the impact of multiple compounds on aquatic organisms is not well understood. Watershed Regressions for Pesticides (WARP) models were developed to predict Pesticide Toxicity Index (PTI) values in unmonitored streams in the Midwest and are referred to as WARP-PTI models. The PTI is a tool for assessing the relative toxicity of pesticide mixtures to fish, benthic invertebrates, and cladocera in stream water. One hundred stream sites in the Midwest were sampled weekly in May through August 2013, and the highest calculated PTI for each site was used as the WARP-PTI model response variable. Watershed characteristics that represent pesticide sources and transport were used as the WARP-PTI model explanatory variables. Three WARP-PTI models—fish, benthic invertebrates, and cladocera—were developed that include watershed characteristics describing toxicity-weighted agricultural use intensity, land use, agricultural management practices, soil properties, precipitation, and hydrologic properties. The models explained between 41 and 48% of the variability in the measured PTI values. WARP-PTI model evaluation with independent data showed reasonable performance with no clear bias. The models were applied to streams in the Midwest to demonstrate extrapolation for a regional assessment to indicate vulnerable streams and to guide more intensive monitoring.

Midwest↗
USGS2012

The Midwest Stream Quality Assessment

In 2013, the U.S. Geological Survey (USGS) National Water-Quality Assessment Program (NAWQA) and USGS Columbia Environmental Research Center (CERC) will be collaborating with the U.S. Environmental Protection Agency (EPA) National Rivers and Streams Assessment (NRSA) to assess stream quality across the Midwestern United States. The sites selected for this study are a subset of the larger NRSA, implemented by the EPA, States and Tribes to sample flowing waters across the United States ( http://water.epa.gov/type/rsl/monitoring/riverssurvey/index.cfm ). The goals are to characterize water-quality stressors—contaminants, nutrients, and sediment—and ecological conditions in streams throughout the Midwest and to determine the relative effects of these stressors on aquatic organisms in the streams. Findings will contribute useful information for communities and policymakers by identifying which human and environmental factors are the most critical in controlling stream quality. This collaborative study enhances information provided to the public and policymakers and minimizes costs by leveraging and sharing data gathered under existing programs. In the spring and early summer, NAWQA will sample streams weekly for contaminants, nutrients, and sediment. During the same time period, CERC will test sediment and water samples for toxicity, deploy time-integrating samplers, and measure reproductive effects and biomarkers of contaminant exposure in fish or amphibians. NRSA will sample sites once during the summer to assess ecological and habitat conditions in the streams by collecting data on algal, macroinvertebrate, and fish communities and collecting detailed physical-habitat measurements. Study-team members from all three programs will work in collaboration with USGS Water Science Centers and State agencies on study design, execution of sampling and analysis, and reporting.

Midwest↗
USGS2011

Bridging the conservation design and delivery gap for wetland bird habitat maintenance and restoration in the Midwestern United States

The U.S. Fish and Wildlife Service's adoption of Strategic Habitat Conservation is intended to increase the effectiveness and efficiency of conservation delivery by targeting effort in areas where biological benefits are greatest. Conservation funding has not often been allocated in accordance with explicit biological endpoints, and the gap between conservation design (the identification of conservation priority areas) and delivery needs to be bridged to better meet conservation goals for multiple species and landscapes. We introduce a regional prioritization scheme for North American Wetlands Conservation Act funding which explicitly addresses Midwest regional goals for wetland-dependent birds. We developed decision-support maps to guide conservation of breeding and non-breeding wetland bird habitat. This exercise suggested ~55% of the Midwest consists of potential wetland bird habitat, and areas suited for maintenance (protection) were distinguished from those most suited to restoration. Areas with greater maintenance focus were identified for central Minnesota, southeastern Wisconsin, the Upper Mississippi and Illinois rivers, and the shore of western Lake Erie and Saginaw Bay. The shores of Lakes Michigan and Superior accommodated fewer waterbird species overall, but were also important for wetland bird habitat maintenance. Abundant areas suited for wetland restoration occurred in agricultural regions of central Illinois, western Iowa, and northern Indiana and Ohio. Use of this prioritization scheme can increase effectiveness, efficiency, transparency, and credibility to land and water conservation efforts for wetland birds in the Midwestern United States.

Midwest↗
USGS2010

Evaluation of aquatic biota in relation to environmental characteristics measured at multiple scales in agricultural streams of the Midwest: 1993-2004

This study evaluated the relations between algal, invertebrate, and fish assemblages and physical environmental characteristics of streams at the reach, segment, and watershed scale in agricultural settings in the Midwest. The 86 stream sites selected for study were in predominantly agricultural watersheds sampled as part of the U.S. Geological Survey's National Water-Quality Assessment Program. Species abundance and over 130 biological metrics were used to determine which aspects of the assemblages were most sensitive to change at the three spatial scales. Digital orthophotograph-based riparian land use/land cover was used for analyses of riparian conditions at the reach and segment scales. The percentage area of different land-use/land-cover types was also determined for each watershed. Out of over 230 environmental characteristics examined, those that best explained variation in the biotic assemblages at each spatial scale include the following: 1) reach: bank vegetative cover, fine silty substrate, and open canopy angle; 2) segment: woody vegetation and cropland in the 250-m riparian buffer, and average length of undisturbed buffer; and 3) watershed: land use/land cover (both total forested and row crop), low-permeability soils, slope, drainage area, and latitude. All three biological assemblages, especially fish, correlated more with land use/land cover and other physical characteristics at the watershed scale than at the reach or segment scales. This study identifies biotic measures that can be used to evaluate potential improvements resulting from agricultural best-management practices and other conservation efforts, as well as evaluate potential impairment from urban development or other disturbances.

Midwest↗
USGS2009

Reconnaissance survey of sulfonamide, sulfonylurea, and imidazolinone herbicides in surface streams and groundwater of the Midwestern United States

The study objective was to conduct a small scale synoptic survey of representative water resources draining agricultural land for occurrence of several herbicide residues. These new classes of herbicides are commonly applied pre-emergence or post-emergence in conservation tillage systems to control grasses and broadleaf weeds in cropped and noncropped areas. Both surface water and groundwater samples were collected from 44 midwestern locations during the summer of 1997, and analyzed for herbicide residues of 15 sulfonylurea and imidazolinone chemicals, and one sulfonamide. Each site was sampled between mid-June and late-October with several stream sites sampled twice. The method, developed jointly by the chemical manufacturer's and the U.S. Environmental Protection Agency, provides a 100 ng/L limit of quantitation in surface water for all analytes. Analytes were detected and identity confirmed in surface water at six sites and in ground water at two sites. The most frequently detected herbicides were imazaquin, imazethapyr, and nicosulfuron. For field studies in which the source of surface and ground water associated with the farming system on the agricultural landscape is known, the sensitivity of the method can be improved with only minor modifications in detection criteria.

Illinois, Indiana, Iowa, Kansas, Michigan, Minneso↗
USGS1998

Herbicides in ground water of the Midwest: A regional study of shallow aquifers, 1991-94

The intensive herbicide use associated with the 'Corn Belt' marks the Midwestern United States as a region where herbicide contamination of ground water could be a problem. To better understand the regional occurrence of herbicides in shallow aquifers of the Midwest, a sampling network of 303 wells across 12 States was developed. The results documented relatively widespread, low-level concentrations of herbicides in the shallow aquifers sampled. The most frequently detected compounds, however, were the transformation products of these herbicides. A relation was determined between herbicide occurrence and the general age of the ground water sampled. Water that recharged ground water within the past 40 years was much more likely to contain herbicides than water recharged earlier.

Midwest↗
USGS1996

Occurrence of alachlor and its sulfonated metabolite in rivers and reservoirs of the midwestern United States: The importance of sulfonation in the transport of chloroacetanilide herbicides

Alachlor and its metabolite, 2-[(2',6'-diethylphenyl)- (methoxymethyl)amino]-2-oxoethanesulfonate (ESA), were identified in 76 reservoirs in the midwestern United States using immunoassay, liquid chromatography, and gas chromatography/mass spectrometry. The median concentration of ESA (0.48 ??g/L) exceeded the median concentration of alachlor (<0.05 ??g/L), with highest values in the upper Midwest. ESA also was detected in the Mississippi River from the mouth to the headwaters at concentrations of 0.2-1.5 ??g/L, exceeding the concentration of alachlor. In a field runoff study, alachlor rapidly formed ESA. It is hypothesized that a glutathione conjugate forms, which later oxidizes in soil to ESA. The removal of the chlorine atom lessens the toxicity of the parent compound and increases runoff potential. It is hypothesized further that sulfonic acid metabolites of other chloroacetanilides, including acetochlor, butachlor, metolachlor, and propachlor, also occur in surface water.

Midwest↗
USGS1955

Water-resources program of the Geological Survey in the Midwestern States

The program of basic water-resources investigations by the U.S Geological Survey in the Midwestern states is a highly coordinated undertaking. It represents a partnership among Federal, State, and participial agencies that has developed during the past 60 years from the mutual desire to obtain and maintain optimum knowledge of out water resources with a minimum outlay of public funds. The program is sufficiently broad to include investigations of water from all natural sources including the chemical and physical quality of water from each of these sources.

Midwest↗