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USGS2001

Relations Among River Stage, Rainfall, Ground-Water Levels, and Stage at Two Missouri River Flood-Plain Wetlands

The source of water is important to the ecological function of Missouri River flood-plain wetlands. There are four potential sources of water to flood-plain wetlands: direct flow from the river channel during high river stage, ground-water movement into the wetlands in response to river-stage changes and aquifer recharge, direct precipitation, and runoff from surrounding uplands. Concurrent measurements of river stage, rainfall, ground-water level, and wetland stage were compared for two Missouri River flood-plain wetlands located near Rocheport, Missouri, to characterize the spatial and temporal relations between river stage, rainfall, ground-water levels and wetland stage, determine the source of water to each wetland, and compare measured and estimated stage and ground-water levels at each site. The two sites chosen for this study were wetland NC-5, a non-connected, 50 feet deep scour constantly filled with water, formed during the flood of 1993, and wetland TC-1, a shallow, temporary wetland intermittently filled with water. Because these two wetlands bracket a range of wetland types of the Missouri River flood plain, the responses of other Missouri River wetlands to changes in river stage, rainfall, and runoff should be similar to the responses exhibited by wetlands NC-5 and TC-1. For wetlands deep enough to intersect the ground-water table in the alluvial aquifer, such as wetland NC-5, the ground-water response factor can estimate flood-plain wetland stage changes in response to known river-stage changes. Measured maximum stage and ground-water-level changes at NC-5 fall within the range of estimated changes using the ground-water response factor. Measured maximum ground-water-level changes at TC-1 are similar to, but consistently greater than the estimated values, and are most likely the result of alluvial deposits with higher than average hydraulic conductivity located between wetland TC-1 and the Missouri River. Similarity between ground-water level and stage hydrography at wetland NC-5 indicate that ground-water-level fluctuations caused by river-stage changes control the stage of wetland NC-5. A 2-day lag time exists between river-stage changes and ground water and stage changes at wetland NC-5. The lack of a measurable response of wetland NC-5 stage to rainfall indicate that rainfall is not a large source of water to wetland NC-5. Stage in wetland TC-1 only increased at high river stage in June and July 1999, and from runoff caused by local rainfall during the winter. The 2-day lag time between peak stages at wetland TC-1 and peak Missouri River stages compared to the 1-day lag time between Missouri River stage and ground-water peaks at wetland TC-1 indicates ground-water flow does not directly affect wetland stage at TC-1, but surface-water flow does affect wetland stage at TC-1 during high river stage. Comparing wetland TC-1 stage to potential water sources indicates the most likely explanation for the rise in stage at wetland TC-1 is surface runoff supplied via seepage through the levees and upward flow of ground water through alluvial deposits of higher hydraulic conductivity during high river stage. The rate of decrease in wetland TC-1 stage was limited by the rate at which ground-water level decreased. Stage response to rainfall at wetland TC-1 during the winter months and no response to greater rainfall amounts during spring and summer months indicate that evapotranspiration may limit the affect of rainfall on stage at wetland TC-1 during the growing season.

Water-Resources Investigations Report↗

USGS2003

A stage-normalized function for the synthesis of stage-discharge relations for the Colorado River in Grand Canyon, Arizona

A method was developed to construct stage-discharge rating curves for the Colorado River in Grand Canyon, Arizona, using two stage-discharge pairs and a stage-normalized rating curve. Stage-discharge rating curves formulated with the stage-normalized curve method are compared to (1) stage-discharge rating curves for six temporary stage gages and two streamflow-gaging stations developed by combining stage records with modeled unsteady flow; (2) stage-discharge rating curves developed from stage records and discharge measurements at three streamflow-gaging stations; and (3) stages surveyed at known discharges at the Northern Arizona Sand Bar Studies sites. The stage-normalized curve method shows good agreement with field data when the discharges used in the construction of the rating curves are at least 200 cubic meters per second apart. Predictions of stage using the stage-normalized curve method are also compared to predictions of stage from a steady-flow model.

Arizona↗

USGS2001

Results of the Utah-Arizona stage-by-stage migrations

In an effort to find a safer means of teaching cranes new migration routes, each year (in 1998 and 1999) we transported a group of greater sandhill cranes (Grus canadensis tabida) stage-by-stage, in a horse trailer, with stops for brief flights at about 30-km intervals, along a 1300-1400-km fall migration route from Fish Springs National Wildlife Refuge (Fish Springs) in west-central Utah to the vicinity of Gila Bend, Arizona. Thereafter, we released them into a wild flock of sandhill cranes. All stage-by-stage birds were hand-reared with both a plastic crane decoy (to encourage them to roost in water) and a costume-draped humanoid form (called a scare-eagle and used for its namesake purpose). When these 2 teaching aids were placed in water, our cranes readily roosted nearby. All but 4 of our cranes proved cooperative (i.e., catchable at each of the ca 25-36 stops) during the migration. All were efficiently released into a wild flock and experienced good survival. The stage-by-stage method proved to be a safe means of transporting cranes south and giving them experience along the route. Some cranes apparently learned their route from the limited experience afforded by releasing them at intervals, and the 1999 cranes have made repealed migrations to or near our chosen northern terminus. However, after 1 winter in our chosen area, the birds have moved elsewhere to winter.

Book chapter↗

USGS2007

Development of an interactive shoreline management tool for the lower Wood River Valley, Oregon, phase 1: Stage-volume and stage-area relations

This report presents the parcel and inundation area geographic information system (GIS) layers for various surface-water stages. It also presents data tables containing the water stage, inundation area, and water volume relations developed from analysis of detailed land surface elevation derived from Light Detection and Ranging (LiDAR) data recently collected for the Wood River Valley at the northern margin of Agency Lake in Klamath County, Oregon. Former shoreline wetlands that have been cut off from Upper Klamath and Agency Lakes by dikes might in the future be reconnected to Upper Klamath and Agency Lakes by breaching the dikes. Issues of interest associated with restoring wetlands in this way include the area that will be inundated, the volume of water that may be stored, the change in wetland habitat, and the variation in these characteristics as surface-water stage is changed. Products from this analysis can assist water managers in assessing the effect of breaching dikes and changing surface-water stage. The study area is in the approximate former northern margins of Upper Klamath and Agency Lakes in the Wood River Valley.

Oregon↗

USGS2011

Chemically-mediated interactions between macroalgae Dictyota spp. and multiple life-history stages of the coral Porites astreoides

Competition between corals and macroalgae is often assumed to occur on reefs, especially those that have undergone shifts from coral to algal dominance; however, data examining these competitive interactions, especially during the early life-history stages of corals, are scarce. We conducted a series of field and outdoor seawater-table experiments to test the hypothesis that allelopathy (chemical inhibition) mediates interactions between 2 common brown macroalgae, Dictyota pulchella and D. pinnatifida , and the coral Porites astreoides at different life-history stages of the coral. D. pinnatifida significantly reduced larval survival and larval recruitment. The extracts of both D. pinnatifida and D. pulchella significantly reduced larval survival, and the extract of D. pulchella also negatively influenced larval recruitment. There was no measurable effect of the crude extracts from Dictyota spp. on the photophysiology of adult corals. Our results provide evidence that these Dictyota species chemically compete with P. astreoides by negatively affecting larval settlement and recruitment as well as the survival of larvae and new recruits. Macroalgae may perpetuate their dominance on degraded reefs by chemically inhibiting the process of coral recruitment.

Marine Ecology Progress Series↗

USGS2003

New K-Ar ages and the geologic evidence against rejuvenated-stage volcanism at Haleakalā, East Maui, a postshield-stage volcano of the Hawaiian island chain

The postshield and previously inferred rejuvenated-stage history of Haleakalā volcano is reevaluated on the basis of 52 new K-Ar ages, 42 from the postshield Kula Volcanics and 10 from the overlying Hāna Volcanics. Postshield extrusion was robust from 0.93 to 0.76 Ma. A period of low extrusion rate or volcanic quiescence occurred between 0.76 and 0.65 Ma, well within Kula time. A chemical change to increasingly alkalic lava occurred at this time as the volcano changed from broadly hawaiitic to basanitic in its eruptive products and robust extrusion resumed. A slightly longer period of low extrusion rate or quiescence occurred after ca. 0.4 Ma, but only trifling change in geochemical character is observed. Geochemically, the Hāna Volcanics unit, chiefly basanitic, overlaps greatly with the upper part of the Kula Volcanics; there is a weak tendency to slightly more alkaline character among the Hāna Volcanics. The age of the Kula/Hāna boundary is ca. 0.15–0.12 Ma; thus, volcanic quiescence of only &sim;0.03 m.y. separates the two formations, much shorter than the previously known limit of 0.25–0.30 m.y. The brevity of this hiatus, coupled with coincident vent loci and broadly similar geochemical characteristics for the Hāna and the upper part of the Kula Volcanics, indicates that the Hāna Volcanics unit comprises deposits of postshield-stage volcanism that has waned substantially since ca. 0.4–0.3 Ma. Haleakalā has not yet begun a classically defined rejuvenated stage. Our findings support recent numerical modeling of plume-lithosphere interactions that predict that Haleakalā is near the end of its postshield growth.

Hawaii↗

USGS2009

Long-Term Stage, Stage-Residual, and Width Data for Streams in the Piedmont Physiographic Region, Georgia

This report presents the data used to assess geomorphic adjustment of streams over time and to changing land-use conditions. Thirty-seven U.S. Geological Survey streamgages were selected within the Piedmont physiographic region of Georgia. Width, depth, stage, and discharge data from these streams were analyzed to assess channel stability and determine if systematic adjustments of channel morphology could be related to time or land use and land cover. Residual analyses of stage-discharge data were used to infer channel stability, which could then be used as an indicator of habitat stability. Streamgages, representing a gradient of urbanization, were selected to test hypotheses regarding stream stability and adjustment to urban conditions. Results indicate that 14 sites exhibited long-term channel stability, 11 were degrading, 6 were aggrading, and 6 showed variability in response over the study period.

Georgia↗

USGS2013

Evidence for an amoeba-like infectious stage of ichthyophonus sp. and description of a circulating blood stage: a probable mechanism for dispersal within the fish host

Small amoeboid cells, believed to be the infectious stage of Ichthyophonus sp., were observed in the bolus (stomach contents) and tunica propria (stomach wall) of Pacific staghorn sculpins and rainbow trout shortly after they ingested Ichthyophonus sp.–infected tissues. By 24–48 hr post-exposure (PE) the parasite morphed from the classically reported multinucleate thick walled schizonts to 2 distinct cell types, i.e., a larger multinucleate amoeboid cell surrounded by a narrow translucent zone and a smaller spherical cell surrounded by a “halo” and resembling a small schizont. Both cell types also appeared in the tunica propria, indicating that they had recently penetrated the columnar epithelium of the stomach. No Ichthyophonus sp. pseudo-hyphae (“germination tubes”) were observed in the bolus or penetrating the stomach wall. Simultaneously, Ichthyophonus sp. was isolated in vitro from aortic blood, which was consistently positive from 6 to 144 hr PE, then only intermittently for the next 4 wk. Small PAS-positive cells observed in blood cultures grew into colonies consisting of non-septate tubules (pseudo-hyphae) terminating in multinucleated knob-like apices similar to those seen in organ explant cultures. Organ explants were culture positive every day; however, typical Ichthyophonus sp. schizonts were not observed histologically until 20–25 days PE. From 20 to 60 days PE, schizont diameter increased from ≤25 μm to ≥82 μm. Based on the data presented herein, we are confident that we have resolved the life cycle of Ichthyophonus sp. within the piscivorous host.

Journal of Parasitology↗

USGS1992

Floating sample-collection platform with stage-activated automatic water sampler for streams with large variation in stage

A floating sample-collection platform is described for stream sites where the vertical or horizontal distance between the stream-sampling point and a safe location for the sampler exceed the suction head of the sampler. The platform allows continuous water sampling over the entire storm-runoff hydrogrpah. The platform was developed for a site in southern Illinois.

Illinois↗

USGS2006

Analysis of mid- and high-stage conditions for the Peconic River at the eastern boundary of Brookhaven National Laboratory, Suffolk County, New York

Brookhaven National Laboratory (BNL) has historically discharged sewage treatment plant (STP) effluent to the Peconic River, which runs through the BNL site in Suffolk County, N.Y. This effluent discharge has averaged about 700,000 gallons per day (about 1.1 cubic feet per second [ft 3 /s]) since 1962 and led to contamination of streambed sediments by radioactive and hazardous constituents. Large sections of the stream channel near BNL are dry during periods of relatively low water-table altitude referred to as low-stage conditions. During mid-stage conditions, the water table intersects the streambed and base flow commences and increases as the water table rises to the tops of the streambanks. Areas adjacent to the stream become flooded during high-stage conditions as the water table rises above the streambanks. Information on the long-term (1943-2003) percentages of time that discharges at two nearby streamflow-gaging stations exceeded thresholds associated with mid- and high-stage conditions is needed to provide a range of estimates of the prevalence and seasonal variability of these conditions during the same years for streamflow-gaging station HQ on the Peconic River at the eastern boundary of BNL. Analysis and correlation of discharge data from the three streamflow-gaging stations—BNL’s station HQ and the U.S. Geological Survey stations on the Peconic River at Riverhead, N.Y., and Carmans River at Yaphank, N.Y.—were performed to extend the 1995-2003 period of record for station HQ. Low-stage conditions occur when there is no flow at station HQ and, therefore, the start-of-flow for the Peconic River is downstream of BNL property. Mid-stage conditions occur when there is flow at station HQ but its daily mean value does not exceed 4.2 ft 3 /s; high-stage conditions occur when this discharge exceeds 4.2 ft 3 /s. Daily mean streamflows at station HQ were associated with low-stage conditions most of the time during 1995-2003 for all flow durations. Low-stage conditions predominated during January, March, and July through December of these years, whereas mid-stage conditions prevailed during parts of February and April through June. Mid-stage conditions generally appeared throughout the year during 1995-2003, except for mid-October, during which only low-stage conditions were observed. High-stage conditions were attained the least amount of time for all flow durations, and appeared only during parts of March through July and December of these years. The percentages of time during 1943-2003 that daily mean streamflows at the Riverhead and Yaphank stations were associated with low-, mid-, and high-stage conditions provide a range of estimates of the amounts of time that these conditions occurred during these years at station HQ. Daily mean streamflows were associated with low-stage conditions most of the time during 1943-2003 for durations of 30 and 60 days; with mid-stage conditions most of the time for durations of 1, 3, and 7 days; and with either of these conditions for a duration of 14 days. High-stage conditions were attained the least amount of time during these years for all durations, except perhaps that of 1 day, for which low-stage conditions could have occurred the least amount of time. Mid-stage conditions predominated during January through early March, June through early July, and late November through December of these years. These conditions typically appeared throughout the year during 1943-2003, and occurred most often during late February. High-stage conditions also generally appeared throughout the year, except perhaps for a few days during early September of these years, and occurred most often during April. These results indicate that streamflows observed during 1943-2003 at the Riverhead and Yaphank stations—used to estimate a longer record for station HQ—were considerably higher than those observed during 1995-2003 at the three stations, and provide information that can be used in future studies to better understand the long-term capacity of streams such as the Peconic River near BNL to supply continuous flow, flood adjacent low-lying areas, and sustain aquatic habitats.

New York↗

USGS1988

Thermochronology of economic mineral deposits: Dating the stages of mineralization at Panasqueira, Portugal, by high-precision 40Ar/ 39Ar age spectrum techniques on muscovite

40 Ar/ 39 Ar age spectrum dates for 13 muscovites have been used to reconstruct the thermal history (thermochronology) of the Panasqueira, Portugal, tin-tungsten deposit, a deposit spatially associated with a belt of Hercynian plutons. Muscovite samples with an age difference as small as 2.2 m.y. (0.7% of the age) are statistically distinct. Statistics are even better for comparison of multiple samples from separate events; that is, a difference of 0.9 m.y. (0.3%) can be resolved in this approximately 300-m.y.-old deposit. The major tin and tungsten ore-forming stages, which are the oxide-silicate stage, the main sulfide stage, and greisenization, occurred between 296.3 + or - 0.8 (1 Sigma ) and 291.6 + or - 0.8 m.y. (1 Sigma ). The first substage of the oxide-silicate stage was a short-lived thermal pulse at 296.3 + or - 0.6 m.y.; the fluids responsible may have emanated from the known granite cupola. The main sulfide stage was active at 294.5 + or - 0.9 m.y. as a slightly longer lived pulse with oldest evidence for this stage (295.8 + or - 0.6 m.y.) coming from areas farthest away from the known cupola and youngest evidence (293.5 + or - 0.8 m.y.) closest to the cupola. A second substage of the oxide-silicate stage occurred as a short-lived thermal pulse at 292.9 + or - 0.7 m.y., synchronous with greisenization of the cupola and alteration of the silica cap at 292.1 + or - 0.4 m.y. The duration of activity of the oxide-silicate stage, the main sulfide stage, greisenization, and alteration of the silica cap based on the ages of all 13 muscovites was greater than 4.2 + or - 0.5 m.y. (1 Sigma ). Minor argon loss from all dated muscovites occurred during later reheating, probably during the longer lived pyrrhotite alteration stage. A single center, the known cupola, had a prolonged role and was the source for main sulfide stage, oxide-silicate stage II, greisenization, and alteration of the silica cap and possibly oxide-silicate stage I and the pyrrhotite alteration stage; however, a separate source for these latter two stages cannot be ruled out.This study is an example of a new and powerful application of 40 Ar/ 39 Ar age spectrum dating of muscovite. Because of the high precision demonstrated in this study, it is now possible to establish time constraints necessary for solving some of the long-standing problems in economic geology. Beyond this, the unique geologic situation of Panasqueira has allowed us to quantify the thermal characteristics of muscovite. Published fluid inclusion data have been used to estimate a muscovite argon closure temperature of approximately 325 degrees C during rapid cooling or short reheating and a temperature of approximately 270 degrees C during slow cooling or extended reheating. Argon-loss patterns displayed by all dated muscovites resulted from reheating after original closure; the mechanism for this argon loss appears to have been argon transport by volume diffusion. Thus, 40 Ar/ 39 Ar age spectrum dating of muscovite can be used to evaluate thermal conditions controlling argon diffusion as well as age, duration, and number of episodes of mineralization.

Economic Geology↗

USGS2019

Residency, recruitment, and stopover duration of hatch-year Roseate Terns (Sterna dougallii) during the pre-migratory staging period

Avian migratory stopover and staging sites represent important energetic bottlenecks and may influence population dynamics as much as breeding or wintering periods. Roseate terns ( Sterna dougallii ) are an ideal species to examine staging demography because >70% of the entire endangered northwest Atlantic population stages at accessible locations around Cape Cod, MA before southward migration. We quantified hatch-year tern weekly residency, weekly recruitment rate into the staging population, and derived weekly staging population growth rate during two post-breeding, pre-migratory staging seasons (2014 and 2015) at Cape Cod National Seashore. We also estimated hatch-year tern staging duration at Cape Cod staging grounds. Tern residency probability at Cape Cod National Seashore during 2014 and 2015 was nearly 1 during the first weeks of the season and decreased steadily over the last four weeks to ~0.5 in the final week of the study. Recruitment rates into the staging population, representing the weekly per capita increase in hatch-year terns during the staging season, indicated that most terns arrived on the staging grounds during the first weeks of the staging season (16 July–19 August). We also identified differences in staging duration between birds from the two breeding regions. Hatch-year terns from the southernmost region spent less time staging at Cape Cod National Seashore than their northern counterparts in both 2014 and 2015. These differences may indicate alternative staging strategies for individuals originating in different regions and possibly reveal differences in conditions between these areas; for example, in the availability of ephemeral prey fish.

Massachusetts↗

USGS2008

Regression Analysis of Stage Variability for West-Central Florida Lakes

The variability in a lake's stage depends upon many factors, including surface-water flows, meteorological conditions, and hydrogeologic characteristics near the lake. An understanding of the factors controlling lake-stage variability for a population of lakes may be helpful to water managers who set regulatory levels for lakes. The goal of this study is to determine whether lake-stage variability can be predicted using multiple linear regression and readily available lake and basin characteristics defined for each lake. Regressions were evaluated for a recent 10-year period (1996-2005) and for a historical 10-year period (1954-63). Ground-water pumping is considered to have affected stage at many of the 98 lakes included in the recent period analysis, and not to have affected stage at the 20 lakes included in the historical period analysis. For the recent period, regression models had coefficients of determination (R2) values ranging from 0.60 to 0.74, and up to five explanatory variables. Standard errors ranged from 21 to 37 percent of the average stage variability. Net leakage was the most important explanatory variable in regressions describing the full range and low range in stage variability for the recent period. The most important explanatory variable in the model predicting the high range in stage variability was the height over median lake stage at which surface-water outflow would occur. Other explanatory variables in final regression models for the recent period included the range in annual rainfall for the period and several variables related to local and regional hydrogeology: (1) ground-water pumping within 1 mile of each lake, (2) the amount of ground-water inflow (by category), (3) the head gradient between the lake and the Upper Floridan aquifer, and (4) the thickness of the intermediate confining unit. Many of the variables in final regression models are related to hydrogeologic characteristics, underscoring the importance of ground-water exchange in controlling the stage of karst lakes in Florida. Regression equations were used to predict lake-stage variability for the recent period for 12 additional lakes, and the median difference between predicted and observed values ranged from 11 to 23 percent. Coefficients of determination for the historical period were considerably lower (maximum R2 of 0.28) than for the recent period. Reasons for these low R2 values are probably related to the small number of lakes (20) with stage data for an equivalent time period that were unaffected by ground-water pumping, the similarity of many of the lake types (large surface-water drainage lakes), and the greater uncertainty in defining historical basin characteristics. The lack of lake-stage data unaffected by ground-water pumping and the poor regression results obtained for that group of lakes limit the ability to predict natural lake-stage variability using this method in west-central Florida.

Scientific Investigations Report↗

USGS2003

Relationship of tadpole stage to location of echinostome cercaria encystment and the consequences for tadpole survival

The effect of echinostome infections on the survival of Rana pipiens tadpoles was examined in relation to developmental stage of tadpoles. Individual tadpoles of Gosner stages 25, 27, 32–33, and 37–39 were exposed to 1 of 4 levels of cercariae (0, 20, 50, or 100). Only tadpoles at stage 25, the earliest stage infected, died within a 5-day experimental period. This stage-specific mortality rate could be explained, in part, by the stage-specific location of encystment of cercariae, which was documented in a separate experiment. In accordance with kidney development, cercariae predominately encysted in the pronephroi during early stages of tadpole development (stages 25 through 31–32) and only in the mesonephroi and associated ducts at later stages (stages 37 through 46). As the mesonephros develops, renal capacity presumably increases. Thus, tadpoles died only when metacercariae concentrated in the functional portion of the kidney with the most limited renal capacity. As tadpoles aged, they also became less susceptible to infections. On average, 69.5% of cercariae that were exposed to stage 25–26 tadpoles successfully encysted, compared with only 8.4% of cercariae exposed to stage 37–38 tadpoles. Exposures of metamorphic frogs (poststage 46) to cercariae revealed that these individuals can become infected with echinostomes. Collectively, our data highlight the host stage–dependent dynamics of tadpole–echinostome interactions.

Journal of Parasitology↗

USGS1996

Migration, fidelity, and use of autumn staging grounds in Alaska by Cackling Canada Geese Branta canadensis minima

Cackling Canada Geese were studied annually (1985-88) on autumn migration staging areas in Alaska during a period of rapid population growth. Geese concentrated at two estuaries (Ugashik Bay and Cinder Lagoon) along the north side of the Alaska Peninsula. Birds arrived on the staging areas in late September, numbers peaked during mid-October, and departure occurred by late October or early November. Annual peak counts combined for the two staging areas ranged from 16,000-54,000 geese, or from 23-120% of the autumn population index. Up to 30,000 geese were recorded at each estuary, but relative use of the two staging areas varied among years. Within-year fidelity to staging areas was high; only three of 242 neck-banded geese seen more than once were observed at both areas within a season. Between-year fidelity to staging areas was highest among hatching-year females (11 of 11) and adult males (14 of 17), lowest among hatching-year males (4 of 9), and intermediate among adult females (18 of 28). Use of the two staging areas was independent of family status, reproductive status, and age. Late arrivals on the staging areas consisted of a higher proportion of single and paired birds than of geese in family groups. Most geese departed the staging grounds with the onset of freezing conditions and the passage of low pressure systems that produced winds favourable for migration. Transoceanic flights to the wintering grounds in Oregon and California were completed in about 48 h. During years with mild weather on the breeding grounds and years with early freezing conditions on the staging areas, few geese staged on the Alaska Peninsula, indicating that geese can sometimes obtain sufficient energy reserves to migrate directly from the breeding grounds without stopping on the staging areas. Only 25% of the area used for staging is legally protected. Use of unprotected areas may become increasingly important if the population continues to increase.

Alaska↗

USGS2020

A within-season approach for detecting early crop stage of corn and soybean using high temporal and spatial resolution imagery

Crop emergence is a critical stage for crop development and crop growth modeling. Mapping crop emergence using remote sensing data is challenging. Previous remote sensing phenology algorithms showed that crop stages could be detected around the V3-V4 (3 to 4 established leaves) vegetative stage. Traditional approaches have a strong assumption regarding the temporal evolution of plant growth and normally require a complete growth period of observations to define seasonal changes. Most approaches were not designed for the within-season mapping in the early growing season. In the current paper, we developed a new within-season emergence (WISE) approach to mapping crop green-up date using satellite observations during early growth stages. The approach was first optimized using high spatiotemporal resolution (10 m, 2 day revisit) imagery from the Vegetation and Environment monitoring New MicroSatellite (VENµS) research mission, and assessed using ground observations of early crop growth stages (emergence VE and one leaf V1 stages for corn, and emergence VE and unifoliolate VC stages for soybeans) collected over the Beltsville Agricultural Research Center (BARC) experimental fields in Beltsville, MD during the 2019 growing season. Results show that early crop growth stages can be reliably detected at sub-field scale about two weeks after crop emergence. The remote sensing green-up dates were about 4-5 days after crop emergence on average. Coefficients of determination (R2) between green-up dates and the mid-point dates of the early growth stages were above 0.90. The mean absolute differences, standard deviations, and root mean square errors comparing to the early growth stage mid-point dates were within six days. The maximum differences were within ±10 days across all fields. The WISE approach was assessed using operational Sentinel-2 data (10 m, 5 day revisit) in BARC. The detected green-up dates from Sentinel-2 were found close to VENµS results. Some fields were not detected due to the lack of observations during emergence dates. For independent evaluation, the WISE approach was applied over an agricultural watershed on the Maryland Eastern Shore using both VENµS and the harmonized Landsat and Sentinel-2 (HLS) data (30 m, 3-4 day revisit). The green-up dates were compared with crop progress reports of crop emergence dates from the National Agricultural Statistics Service (NASS) at the state-level. The WISE -detected green-up dates at the regional scale are within VE stage ranges but slightly earlier than NASS crop progress reports at the state-level. The WISE approach uses remote sensing observations during the early crop growth stages and has potential for operational application within the season using Sentinel-2 and HLS data.

Maryland↗

USGS2022

Bathymetric map, surface area, and stage-capacity for the U.S. part of Lake Koocanusa, Lincoln County, Montana, 2016–18

The U.S. Geological Survey and U.S. Army Corps of Engineers collected high-resolution multibeam sonar data during 2016–18 to compute stage-area and stage-capacity tables for the U.S. part of Koocanusa Reservoir in Lincoln County, northwestern Montana. Koocanusa Reservoir is a transboundary reservoir extending about 48 miles from Libby Dam upstream to the U.S. international boundary with Canada and another 42 miles within Canada to near Wardner, British Columbia. The upstream extent of the reservoir within Canada, where much of the sedimentation was previously documented, was not included in this study. Previously developed stage-area and stage-capacity tables were developed for the entire reservoir and could not be directly compared to the stage-area and stage-capacity tables from this study. Two discrete stage-area and stage-capacity values from the original survey (unknown survey date prior to 1980) were available for parts of the reservoir within the United States at the normal full-pool and normal minimum-pool elevations (2,459 and 2,287 U.S. survey feet above the National Geodetic Vertical Datum of 1929, respectively). At the normal full-pool elevation, the stage-area relation resulted in a 0.06-percent increase in surface-water acreage. Conversely, a 0.03-percent decrease in storage capacity at the normal full-pool elevation occurred. At the normal-minimum-pool elevation, the stage-area relation showed a 1.21-percent decrease in surface water from 14,487 to 14,314 acres. The usable storage capacity, defined as the volume of water between the normal full-pool and normal minimum-pool elevations, decreased by 0.39 percent (15,353 acre-feet). Results from this study indicate that a relatively minimal amount of sedimentation has occurred since initial filling in Koocanusa Reservoir for parts of the reservoir within the United States. Updated stage-area and stage-capacity tables for the entire reservoir will require additional bathymetric and topographic surveys for the parts of Koocanusa Reservoir within Canada.

Montana↗

USGS1999

Effects on ground-water levels in the Missouri River alluvial aquifer caused by changes in Missouri River stage, Fremont and Monona Counties, Iowa

An analysis of available hydrologic data was conducted to evaluate the effects on groundwater levels in the Missouri River alluvial aquifer caused by changes in Missouri River stage at selected sites in Fremont and Monona Counties in western Iowa. Daily mean ground-water levels and river stage measured during November 1995- September 1996, simulated daily mean river stage for November 1995-December 1996 derived from simulated daily mean discharge for eight alternative water-management plans for the Missouri River, and simulated daily mean ground-water levels for November 1995- December 1996 for selected water-management plans were used in the study. The measured data represent hydrologic conditions for the Current (1998) Water-Control Plan of the U.S. Army Corps of Engineers. Ground-water levels in the alluvial aquifer vary in response to river stage, precipitation, proximity to drainage ditches, evapotranspiration, and pumpage. In Fremont County, measured ground-water levels generally were lower than river stage during the spring, summer, and fall months. In Monona County, measured ground-water levels generally were higher than river stage. Water levels in wells at distances greater than about 8,000 feet from the river in Fremont County and about 6,500 feet in Monona County likely were more affected by precipitation or proximity to drainage ditches than by river stage. Changes in river stage likely affect groundwater levels in Fremont County to a greater degree than in Monona County. In Fremont County, the hydraulic gradient generally is from the river to the aquifer; in Monona County, the gradient generally is from the aquifer to the river. The response of ground- water levels to changes in river stage in Monona County is less apparent than in Fremont County. The higher ground-water levels in Monona County indicate that the effects of other factors, such as differences in recharge from precipitation and aquifer properties, are more dominant than in Fremont County. Generally, the effects of simulated river stage caused higher simulated ground-water levels in Fremont and Monona Counties at distances less than 10,000 feet from the river during the spring months for selected alternatives to the Current Water-Control Plan that target increased benefits to fish and wildlife. Local hydrogeologic conditions will determine how significantly the possible 1- to 4-foot change in ground-water levels affects land use within 10,000 feet of the river. For example, lower river stage and ground-water levels during the mid-summer months could improve drainage in lowland areas during periods of greater-than-normal precipitation. Actual depth to ground water might be controlled by factors other than river stage, such as proximity to drainage ditches and local differences in recharge by precipitation, discharge from evapotranspiration, aquifer properties, and land-surface altitude.

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