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Exploring the news media and scientific conversations around water quality in a water-rich basin of the United States
Community concerns about water availability vary depending on local economic, regulatory, environmental, and ecological considerations. In water-rich basins, water quality is often the focus of community concerns. As such, understanding community priorities in the context of water quality is crucial for informing scientists working in water-rich basins. In this work, we compiled over 6,500 local news articles (public discourse) and 190 scientific abstracts (scientific discourse) related to water-quality issues in the water-rich Illinois River Basin (ILRB) published between 2018 and 2022. We applied a Structural Topic Model (STM) to identify key water-quality topics within both datasets and explore the variability of newspaper topics geographically across the basin. Prevalent topics in both the public (local news articles) and scientific (abstracts) discourses were agriculture, drinking water quality, PFAS (per- and polyfluoroalkyl substances), and river ecosystem/fish. Topics exclusive to public discourse included water infrastructure, community development, and public water supply, while the scientific discourse focused more heavily on a wider range of agricultural issues. Furthermore, the public discourse varied geographically across the basin. Some topics are correlated with land use or urban/rural divides within the basin, and the frequency of many topics clearly varied across state (political) boundaries. Understanding and quantifying public and scientific discourses related to water-quality are important for scientists and water managers working in the basin to improve communication of critical science to the public.
Implications of spatially variable costs and habitat conversion risk in landscape-scale conservation planning
“Strategic habitat conservation” refers to a process used by the U.S. Fish and Wildlife Service to develop cost-efficient strategies for conserving wildlife populations and their habitats. Strategic habitat conservation focuses on resolving uncertainties surrounding habitat conservation to meet specific wildlife population objectives (i.e., targets) and developing tools to guide where conservation actions should be focused on the landscape. Although there are examples of using optimization models to highlight where conservation should be delivered, such methods often do not explicitly account for spatial variation in the costs of conservation actions. Furthermore, many planning approaches assume that habitat protection is a preferred option, but they do not assess its value relative to other actions, such as restoration. We developed a case study to assess the implications of accounting for and ignoring spatial variation in conservation costs in optimizing conservation targets. We included assumptions about habitat loss to determine the extent to which protection or restoration would be necessary to meet an established population target. Our case study focused on optimal placement of grassland protection or restoration actions to influence bobolink Dolichonyx oryzivorus populations in the tallgrass prairie ecoregion of the north central United States. Our results show that not accounting for spatially variable costs doubled or tripled the cost of meeting the population target. Furthermore, our results suggest that one should not assume that protecting existing habitat is always a preferred option. Rather, our results show that the balance between protection and restoration can be influenced by a combination of desired targets, assumptions about habitat loss, and the relative cost of the two actions. Our analysis also points out how difficult it may be to reach targets, given the expense to meet them. We suggest that a full accounting of expected costs and benefits will help to guide development of viable management actions and meaningful conservation plans.
An empirical model of the phytoplankton chlorophyll : carbon ratio-the conversion factor between productivity and growth rate
We present an empirical model that describes the ratio of phytoplankton chlorophyll a to carbon, Chl: C, as a function of temperature, daily irradiance, and nutrient-limited growth rate. Our model is based on 219 published measurements of algal cultures exposed to light-limited or nutrient-limited growth conditions. We illustrate an approach for using this estimator of Chl: C to calculate phytoplankton population growth rate from measured primary productivity. This adaptive Chl: C model gives rise to interactive light-nutrient effects in which growth efficiency increases with nutrient availability under low-light conditions. One implication of this interaction is the enhancement of phytoplankton growth efficiency, in addition to enhancement of biomass yield, as a response to eutrophication.
Digital to Analog Conversion and Visual Evaluation of Thematic Mapper Data
As a part of the National Aeronautics and Space Administration Landsat D Image Data Quality Analysis Program, the Earth Resources Observation Systems Data Center (EDC) developed procedures to optimize the visual information content of Thematic Mapper data and evaluate the resulting photographic products by visual interpretation. A digital-to-analog transfer function was developed which would properly place the digital values on the most useable portion of a film response curve. Individual black-and-white transparencies generated using the resulting look-up tables were utilized in the production of color-composite images with varying band combinations. Four experienced photointerpreters ranked 2-cm-diameter (0. 75 inch) chips of selected image features of each band combination for ease of interpretability. A nonparametric rank-order test determined the significance of interpreter preference for the band combinations.
Digital to analog conversion and visual evaluation of Thematic Mapper data
As a part of the National Aeronautics and Space Administration Landsat D Image Data Quality Analysis Program, the Earth Resources Observation Systems Data Center (EDC) developed procedures to optimize the visual information content of Thematic Mapper data and evaluate the resulting photographic products by visual interpretation. A digital-to-analog transfer function was developed which would properly place the digital values on the most useable portion of a film response curve. Individual black-and-white transparencies generated using the resulting look-up tables were utilized in the production of color-composite images with varying band combinations. Four experienced photointerpreters ranked 2-cm-diameter (0. 75 inch) chips of selected image features of each band combination for ease of interpretability. A nonparametric rank-order test determined the significance of interpreter preference for the band combinations.
Conversion of wetlands for agriculture and other land development
No abstract available.
Time-to-depth conversion of seismic-reflection data from eastern Lake Superior and implications for the eastern arm of the Midcontinent Rift
Seismic-reflection data were acquired in the mid 1980s along several lines across eastern Lake Superior by industry and the Great Lakes International Multidisciplinary Program on Crustal Evolution (GLIMPCE) (Fig. 1). The lines form part of a larger network of crossing lines over the entire lake, which can be used to develop three-dimensional geologic models of the Mesoproterozoic Midcontinent Rift that lies below. To better interpret these lines, we developed velocity models to convert seismic reflections versus two-way travel time (TWTT) to reflections versus depth. In addition, the velocity models themselves provide insights into the structure of the Midcontinent Rift by recognizing common velocity ranges for certain rock types (Grauch, 2023).
Growth models and food conversion of cultured juvenile red abalone (Haliotis rufescens)
No abstract available at this time
Potential future land use threats to California's protected areas
Increasing pressures from land use coupled with future changes in climate will present unique challenges for California’s protected areas. We assessed the potential for future land use conversion on land surrounding existing protected areas in California’s twelve ecoregions, utilizing annual, spatially explicit (250 m) scenario projections of land use for 2006–2100 based on the Intergovernmental Panel on Climate Change Special Report on Emission Scenarios to examine future changes in development, agriculture, and logging. We calculated a conversion threat index (CTI) for each unprotected pixel, combining land use conversion potential with proximity to protected area boundaries, in order to identify ecoregions and protected areas at greatest potential risk of proximal land conversion. Our results indicate that California’s Coast Range ecoregion had the highest CTI with competition for extractive logging placing the greatest demand on land in close proximity to existing protected areas. For more permanent land use conversions into agriculture and developed uses, our CTI results indicate that protected areas in the Central California Valley and Oak Woodlands are most vulnerable. Overall, the Eastern Cascades, Central California Valley, and Oak Woodlands ecoregions had the lowest areal percent of protected lands and highest conversion threat values. With limited resources and time, rapid, landscape-level analysis of potential land use threats can help quickly identify areas with higher conversion probability of future land use and potential changes to both habitat and potential ecosystem reserves. Given the broad range of future uncertainties, LULC projections are a useful tool allowing land managers to visualize alternative landscape futures, improve planning, and optimize management practices.
Hydrologic conditions near Glendo, Platte County, Wyoming
The Glendo area of Platte and Carbon Counties, Wyo., about 250 square miles in extent, is in the Great Plains physiographic province. It is bordered on the west by the Laramie Range and on the east by the Hartville uplift. The North Platte River and Horseshoe and Middle Bear Creeks are the principal streams that drain the area. Gentle to steep hills, which lie between 4,450 and 6,360 feet above sea level, characterize the topography. Approximately 7,600 acres of land is cultivated in the Horseshoe Creek valley and 1,000 or more acres in the Cassa Flats of the North Platte River and Middle Bear Creek valleys. The average annual precipitation of 13.15 inches and the streamflow diverted for irrigation from Horseshoe Creek and the North Platte River are usually inadequate to sustain crops during the entire growing season. Sedimentary rocks, which underlie about 99 percent of the Glendo area, range in age from Cambrian(?) to Recent and in thickness from about 3,000 to 4,700 feet. Beds of Paleozoic and Mesozoic age dip steeply away from the Laramie Range and the Hartville uplift to form a large syncline, which is interrupted by the Elkhorn anticline in the central part of the area. Beds of Tertiary and Quaternary age that were deposited over the older structural features and later were partly removed by erosion have dips of less than 6 ? . The 'Converse sand' of local usage at the top of the Hartville Formation of Mississippian(7), Pennsylvanian, and Permian age, the White River Formation of Oligocene age, and the flood-plain deposits of Recent .age are the most important aquifers in the Glendo area. The Hartville Formation consists predominantly of hard limestone and dolomite and of lesser amounts of sandstone and shale ; its thickness ranges from 850 to 1,050 feet throughout most of the area. The 'Converse sand' is an artesian aquifer consisting of fine- to medium-grained porous sandstone having an average thickness of about 80 feet. Recharge to the Hartville Formation is mainly from seepage of surface water from Glendo Reservoir and Spring Creek; ground water is discharged from the formation to the overlying White River Formation and the alluvium in the North Platte River valley near Cassa and to four wells in the Horseshoe Creek valley. Flowing wells yielding from a few gallons per minute to 175 gpm (gallons per minute) or more from the 'Converse sand' can probably be located in an area from ? mile to 1? miles wide and about 4? miles long in the lower Horseshoe Creek valley. The depth to the 'Converse sand' in this area depends upon the topographic relief and distance from the outcrop and ranges from 250 to about 1,000 feet. The discharge induced by pumping a well in the aquifer in the 'Converse sand' would probably amount to about 2 gpm per foot of drawdown. Values of 2,000, 2,100, and 10,300 gpd (gallons per day) per ft for the coefficient of transmissibility of the 'Converse sand' were obtained from aquifer tests at three wells. The chemical analyses of samples from the Hartville Formation ('Converse. sand' included) indicate that the water in the formation is of fairly good quality and adequate for domestic, stock, and irrigation uses, although the fluoride content is low and the water is hard. The White River Formation is composed of as much as 575 feet of fractured siltstone and claystone, and the flood-plain deposits include up to 65 feet of silt, sand, and gravel. Precipitation is the main type of recharge to the rocks of Tertiary age. Recharge to the alluvium in the valleys of Horseshoe Creek and the North Platte River occurs mainly by seepage of ground water from. underlying beds, by infiltration of irrigation water, and by infiltration of streamflow as bank storage. Ground water is discharged naturally from the area by seepage to streams, by underflow, and by evapotranspiration and artificially by wells. In 1961, the total discharge from 38 wells in the White River and Arikaree Formations and 2
New biotite and muscovite isotopic reference materials, USGS57 and USGS58, for δ2H measurements–A replacement for NBS 30
The advent of continuous-flow isotope-ratio mass spectrometry (CF-IRMS) coupled with a high temperature conversion (HTC) system enabled faster, more cost effective, and more precise δ 2 H analysis of hydrogen-bearing solids. Accurate hydrogen isotopic analysis by on-line or off-line techniques requires appropriate isotopic reference materials (RMs). A strategy of two-point calibrations spanning δ 2 H range of the unknowns using two RMs is recommended. Unfortunately, the supply of the previously widely used isotopic RM, NBS 30 biotite, is exhausted. In addition, recent measurements have shown that the determination of δ 2 H values of NBS 30 biotite on the VSMOW-SLAP isotope-delta scale by on-line HTC systems with CF-IRMS may be unreliable because hydrogen in this biotite may not be converted quantitatively to molecular hydrogen. The δ 2 H VSMOW-SLAP values of NBS 30 biotite analyzed by on-line HTC systems can be as much as 21 mUr (or ‰) too positive compared to the accepted value of − 65.7 mUr, determined by only a few conventional off-line measurements. To ensure accurate and traceable on-line hydrogen isotope-ratio determinations in mineral samples, we here propose two isotopically homogeneous, hydrous mineral RMs with well-characterized isotope-ratio values, which are urgently needed. The U.S. Geological Survey (USGS) has prepared two such RMs, USGS57 biotite and USGS58 muscovite. The δ 2 H values were determined by both glassy carbon-based on-line conversion and chromium-based on-line conversion, and results were confirmed by off-line conversion. The quantitative conversion of hydrogen from the two RMs using the on-line HTC method was carefully evaluated in this study. The isotopic compositions of these new RMs with 1-σ uncertainties and mass fractions of hydrogen are: USGS57 (biotite) δ 2 H VSMOW-SLAP = − 91.5 ± 2.4 mUr ( n = 24) Mass fraction hydrogen = 0.416 ± 0.002% ( n = 4) Mass fraction water = 3.74 ± 0.02% ( n = 4) USGS58 (muscovite) δ 2 H VSMOW-SLAP = − 28.4 ± 1.6 mUr ( n = 24) Mass fraction hydrogen = 0.448 ± 0.002% ( n = 4) Mass fraction water = 4.03 ± 0.02% ( n = 4). These δ 2 H VSMOW-SLAP values encompass typical ranges for solid unknowns of crustal and mantle origin and are available to users for recommended two-point calibration.
Bioavailability of dissolved organic matter varies with anthropogenic landcover in the Upper Mississippi River Basin
Anthropogenic conversion of forests and wetlands to agricultural and urban landcovers impacts dissolved organic matter (DOM) within streams draining these catchments. Research on how landcover conversion impacts DOM molecular level composition and bioavailability, however, is lacking. In the Upper Mississippi River Basin (UMRB), water from low-order streams and rivers draining one of three dominant landcovers (forest, agriculture, urban) was incubated for 28 days to determine bioavailable DOC (BDOC) concentrations and changes in DOM composition. The BDOC concentration averaged 0.49 ± 0.30 mg L −1 across all samples and was significantly higher in streams draining urban catchments (0.72 ± 0.34 mg L −1 ) compared to streams draining agricultural (0.28 ± 0.15 mg L −1 ) and forested (0.47 ± 0.17 mg L −1 ) catchments. Percent BDOC was significantly greater in urban (10% ± 4.4%) streams compared to forested streams (5.6% ± 3.2%), corresponding with greater relative abundances of aliphatic and N-containing aliphatic compounds in urban streams. Aliphatic compound relative abundance decreased across all landcovers during the bioincubation (average -4.1% ± 10%), whereas polyphenolics and condensed aromatics increased in relative abundance across all landcovers (average of +1.4% ± 5.9% and +1.8% ± 10%, respectively). Overall, the conversion of forested to urban landcover had a larger impact on stream DOM bioavailability in the UMRB compared to conversion to agricultural landcover. Future research examining the impacts of anthropogenic landcover conversion on stream DOM composition and bioavailability needs to be expanded to a range of spatial scales and to different ecotones, especially with continued landcover alterations.
Mississippi Basin Carbon Project: Upland soil database for sites in Nishnabotna River basin, Iowa
The conversion of land from its native state to an agricultural use commonly results in a significant loss of soil carbon (Mann, 1985; Davidson and Ackerman, 1993). Globally, this loss is estimated to account for as much as 1/3 of the net CO 2 emissions for the period of 1850 to 1980 (Houghton and others, 1983). Roughly 20 to 40 percent of original soil carbon is estimated to be lost as CO 2 as a result of agricultural conversion, or "decomposition enhancement". Global models use this estimate along with land conversion data to provide agricultural contributions of CO 2 emissions for global carbon budgets (Houghton and others, 1983; Schimel, 1995). Soil erosion rates are significantly (10X) higher on croplands than on their undisturbed equivalents (Dabney and others, 1997). Most of the concern over erosion is related to diminished productivity of the uplands (Stallings, 1957; McGregor and others, 1969; Rhoton, 1990) or to increased hazards and navigability of the lowlands in the late 1800's to early 1900's. Yet because soil carbon is concentrated at the soil surface, with an exponential decline in concentration with depth (Harden et al, 1999), it is clear that changes in erosion rates seen on croplands must also impact soil carbon storage and terrestrial carbon budgets as well. As yet, erosional losses of carbon are not included in global carbon budgets explicitly as a factor in land conversion nor implicitly as a portion of the decomposition enhancement. However, recent work by Lal and others (1995) and by Stallard (1998) suggests that significant amounts of eroded soil may be stored in man-made reservoirs and depositional environments as a result of agricultural conversion. Moreover, Stallard points out that eroding soils have the potential for replacing part of the carbon trapped in man-made reservoirs. If true, then the global carbon budget may grossly underestimate or ignore a significant sink term resulting from the burial of eroded soil.