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USGS2012

An Automated Cropland Classification Algorithm (ACCA) for Tajikistan by combining Landsat, MODIS, and secondary data

The overarching goal of this research was to develop and demonstrate an automated Cropland Classification Algorithm (ACCA) that will rapidly, routinely, and accurately classify agricultural cropland extent, areas, and characteristics (e.g., irrigated vs. rainfed) over large areas such as a country or a region through combination of multi-sensor remote sensing and secondary data. In this research, a rule-based ACCA was conceptualized, developed, and demonstrated for the country of Tajikistan using mega file data cubes (MFDCs) involving data from Landsat Global Land Survey (GLS), Landsat Enhanced Thematic Mapper Plus (ETM+) 30 m, Moderate Resolution Imaging Spectroradiometer (MODIS) 250 m time-series, a suite of secondary data (e.g., elevation, slope, precipitation, temperature), and in situ data. First, the process involved producing an accurate reference (or truth) cropland layer (TCL), consisting of cropland extent, areas, and irrigated vs. rainfed cropland areas, for the entire country of Tajikistan based on MFDC of year 2005 (MFDC2005). The methods involved in producing TCL included using ISOCLASS clustering, Tasseled Cap bi-spectral plots, spectro-temporal characteristics from MODIS 250 m monthly normalized difference vegetation index (NDVI) maximum value composites (MVC) time-series, and textural characteristics of higher resolution imagery. The TCL statistics accurately matched with the national statistics of Tajikistan for irrigated and rainfed croplands, where about 70% of croplands were irrigated and the rest rainfed. Second, a rule-based ACCA was developed to replicate the TCL accurately (∼80% producer’s and user’s accuracies or within 20% quantity disagreement involving about 10 million Landsat 30 m sized cropland pixels of Tajikistan). Development of ACCA was an iterative process involving series of rules that are coded, refined, tweaked, and re-coded till ACCA derived croplands (ACLs) match accurately with TCLs. Third, the ACCA derived cropland layers of Tajikistan were produced for year 2005 (ACL2005), same year as the year used for developing ACCA, using MFDC2005. Fourth, TCL for year 2010 (TCL2010), an independent year, was produced using MFDC2010 using the same methods and approaches as the one used to produce TCL2005. Fifth, the ACCA was applied on MFDC2010 to derive ACL2010. The ACLs were then compared with TCLs (ACL2005 vs. TCL2005 and ACL2010 vs. TCL2010). The resulting accuracies and errors from error matrices involving about 152 million Landsat (30 m) pixels of the country of Tajikistan (of which about 10 million Landsat size, 30 m, cropland pixels) showed an overall accuracy of 99.6% (k hat = 0.97) for ACL2005 vs. TCL2005. For the 3 classes (irrigated, rainfed, and others) mapped in ACL2005, the producer’s accuracy was >86.4% and users accuracy was >93.6%. For ACL2010 vs. TCL2010, the error matrix showed an overall accuracy on 96.2% (k hat = 0.96). For the 3 classes (irrigated, rainfed, and others) mapped in ACL2010, the producer’s and user’s accuracies for the irrigated areas were ≥82.9%. Any intermixing was overwhelmingly between irrigated and rainfed croplands, indicating that croplands (irrigated plus rainfed areas) as well as irrigated areas were mapped with high levels of accuracies (∼90% or higher) even for the independent year. The ACL2005 and ACL2010, each, were produced using ACCA algorithm in ∼30 min using a Dell Precision desktop T7400 computer for the entire country of Tajikistan once the MFDCs for the years were ready. The ACCA algorithm for Tajikistan is made available through US Geological Survey’s ScienceBase: http://www.sciencebase.gov/catalog/folder/4f79f1b7e4b0009bd827f548 or at: https://powellcenter.usgs.gov/globalcroplandwater/content/models-algorithms . The research contributes to the efforts of global food security through research on global croplands and their water use (e.g., https://powellcenter.usgs.gov/globalcroplandwater/ ). The above results clearly demonstrated the ability of a rule-based ACCA to rapidly and accurately produce cropland data layer year after year (hindcast, nowcast, forecast) for the country it was developed using MFDCs that consist of combining multiple sensor data and secondary data. It needs to be noted that the ACCA is applicable to the area (e.g., country, region) for which it is developed. In this case, ACCA is applicable for the Country of Tajikistan to hindcast, nowcast, and forecast agricultural cropland extent, areas, and irrigated vs. rainfed. The same fundamental concept of ACCA applies to other areas of the World where ACCA codes need to be modified to suite the area/region of interest. ACCA can also be expanded to compute other crop characteristics such as crop types, cropping intensities, and phenologies.

Remote Sensing↗

USGS2015

Groundwater – The disregarded component in lake water and nutrient budgets. Part 2: effects of groundwater on nutrients

Lacustrine groundwater discharge (LGD) transports nutrients from a catchment to a lake, which may fuel eutrophication, one of the major threats to our fresh waters. Unfortunately, LGD has often been disregarded in lake nutrient studies. Most measurement techniques are based on separate determinations of volume and nutrient concentration of LGD: Loads are calculated by multiplying seepage volumes by concentrations of exfiltrating water. Typically low phosphorus (P) concentrations of pristine groundwater often are increased due to anthropogenic sources such as fertilizer, manure or sewage. Mineralization of naturally present organic matter might also increase groundwater P. Reducing redox conditions favour P transport through the aquifer to the reactive aquifer-lake interface. In some cases, large decreases of P concentrations may occur at the interface, for example, due to increased oxygen availability, while in other cases, there is nearly no decrease in P. The high reactivity of the interface complicates quantification of groundwater-borne P loads to the lake, making difficult clear differentiation of internal and external P loads to surface water. Anthropogenic sources of nitrogen (N) in groundwater are similar to those of phosphate. However, the environmental fate of N differs fundamentally from P because N occurs in several different redox states, each with different mobility. While nitrate behaves essentially conservatively in most oxic aquifers, ammonium's mobility is similar to that of phosphate. Nitrate may be transformed to gaseous N 2 in reducing conditions and permanently removed from the system. Biogeochemical turnover of N is common at the reactive aquifer-lake interface. Nutrient loads from LGD were compiled from the literature. Groundwater-borne P loads vary from 0.74 to 2900 mg PO 4 -P m −2 year −1 ; for N, these loads vary from 0.001 to 640 g m −2 year −1 . Even small amounts of seepage can carry large nutrient loads due to often high nutrient concentrations in groundwater. Large spatial heterogeneity, uncertain areal extent of the interface and difficult accessibility make every determination of LGD a challenge. However, determinations of LGD are essential to effective lake management.

Hydrological Processes↗

USGS2006

Water color affects the stratification, surface temperature, heat content, and mean epilimnetic irradiance of small lakes

The effects of water color on lake stratification, mean epilimnetic irradiance, and lake temperature dynamics were examined in small, north-temperate lakes that differed widely in water color (1.5-19.8 m -1). Among these lakes, colored lakes differed from clear lakes in the following ways: (i) the epilimnia were shallower and colder, and mean epilimnetic irradiance was reduced; (ii) the diel temperature cycles were more pronounced; (iii) whole-lake heat accumulation during stratification was reduced. The depth of the epilimnion ranged from 2.5 m in the clearest lake to 0.75 m in the most colored lake, and 91% of the variation in epilimnetic depth was explained by water color. Summer mean morning epilimnetic temperature was ???2??C cooler in the most colored lake compared with the clearest lake. In clear lakes, the diel temperature range (1.4 ?? 0.7??C) was significantly (p = 0.01) less than that in the most colored lake (2.1 ?? 1.0??C). Change in whole-lake heat content was negatively correlated with water color. Increasing water color decreased light penetration more than thermocline depth, leading to reduced mean epilimnetic irradiance in the colored lakes. Thus, in these small lakes, water color significantly affected temperature, thermocline depth, and light climate. ?? 2006 NRC.

Canadian Journal of Fisheries and Aquatic Sciences↗

USGS2017

Health and condition of endangered young-of-the-year Lost River and Shortnose suckers relative to water quality in Upper Klamath Lake, Oregon, 2014–2015

Most mortality of endangered Lost River ( Deltistes luxatus ) and shortnose ( Chasmistes brevirostris ) suckers in Upper Klamath Lake, Oregon, occurs within the first year of life. Juvenile suckers in Clear Lake Reservoir, California, survive longer and may even recruit to the spawning populations. In a previous (2013–2014) study, the health and condition of juvenile suckers and the dynamics of water quality between Upper Klamath Lake and Clear Lake Reservoir were compared. That study found that apparent signs of stress or exposure to irritants, such as peribiliary cuffing in liver tissue and mild inflammation and necrosis in gill tissues, were present in suckers from both lakes and were unlikely to be clues to the cause of differential mortality between lakes. Seasonal trends in energy storage as glycogen and triglycerides were also similar between lakes, indicating prey limitation was not a likely factor in differential mortality. To better understand the relationship between juvenile sucker health and water quality, we examined suckers collected in 2014–2015 from Upper Klamath Lake, where water quality can be dynamic and, at times, extreme. While there were notable differences in water quality and fish health between years, we were not able to identify any specific water-quality-related causes for differential fish condition. Water quality was generally better in 2014 than in 2015. When considered together afflictions and abnormalities generally indicated healthier suckers in 2014 than 2015. Low dissolved-oxygen events (< 4 milligrams per liter) were less frequent and occurred earlier; high pH events (≥ 9.5) were less frequent and shorter in duration; large diel fluctuations in pH (≥ 1.4) were less frequent; water temperatures were warmer, particularly in July and September; and concentrations of microcystin in both large and small fractions of samples were lower in 2014 than in 2015. Total and therefore also un-ionized ammonia were low in 2014–2015 relative to concentrations known to affect suckers. Petechial hemorrhages of the skin, attached Lernaea spp. and eosinophilic hyaline droplets in the kidney tubules were less prevalent in 2014 than in 2015; however, hyperplastic and hypertrophic gill tissue and trichodinids on the gills were observed more frequently in 2014. There were more suckers with normal liver color and texture in 2014 than in 2015. The prevalence of suckers with liver inflammation was greater in 2014 and only observed in suckers collected after August 5, whereas liver inflammation occurred intermittently in 2015. Liver glycogen among suckers decreased in late-August 2014 and increased from early August to mid-September 2015. Lost River suckers had greater whole-body triglyceride content but a larger proportion with an absence of visceral fat observed in 2014 than in 2015. In contrast, shortnose suckers were similar between years in regard to both whole-body triglyceride and visceral fat. Black-spot-forming parasites (trematode metacercariae) were observed in a higher prevalence on shortnose suckers but not Lost River suckers in 2014 than in 2015. Opercular deformities were less prevalent in both species in 2014 than in 2015. Neither gross nor histological examination revealed a high prevalence of abnormalities in suckers that clearly indicate a primary mechanism for juvenile mortality in Upper Klamath Lake. Histological abnormalities were almost always focal and minimal or mild except where associated with parasites. Mild to severe focal abnormalities associated with Lernaea sp. attachment sites and encysted digenean (trematode) metacercariae are unlikely to be associated with mortality. Severe and diffuse inflammation and hyperplasia of the gills associated with Ichthyobodo sp. on one Lost River sucker, may indicate a potential cause of mortality. High mortality may have primarily occurred outside our study period (for example, in spring or over winter), or was caused by a factor that could not be detected with our methods (for example, predation). Alternatively, abnormalities in a small percentage of passively captured suckers in Upper Klamath Lake may indicate health-related issues that were more prevalent in populations than in our samples. Temporary decreases in liver glycogen stores may also indicate periods of stress, which may eventually lead to mortality of young suckers.

Oregon↗

USGS2019

Hydrologic Influences on Water Levels at Three Oaks Recreation Area, Crystal Lake, Illinois, April 14 through September 27, 2016

Hydrologic influences on water levels were investigated at Three Oaks Recreation Area (TORA), a former sand-and-gravel quarry converted into recreational lakes in Crystal Lake, Illinois. From 2009 to 2015, average water levels in the lakes declined nearly 4 feet. It was not clear if these declines were related to variations in weather (precipitation or evaporation) or other hydrologic influences such as municipal supply pumping or nearby quarry operations. Data were collected using three approaches to determine the possibility of such hydrologic influences. First, water levels were collected at 15 minute intervals at three wells equipped with pressure transducers from April 14 through September 27, 2016. The continuous data allowed assessment of lake and well water level responses to precipitation, pumping influences, and quarry operations. Second, a single-day synoptic water-level survey was completed to create a water table map to determine groundwater flow directions. Third, single-well aquifer tests (slug tests) were completed on the three data-collection wells to estimate the aquifer’s horizontal hydraulic conductivity. Collectively, these data were used to determine the velocity and volume of water entering and exiting TORA.

Illinois↗

USGS2007

Response of Stream Chemistry During Base Flow to Gradients of Urbanization in Selected Locations Across the Conterminous United States, 2002-04

During 2002-2004, the U.S. Geological Survey's National Water-Quality Assessment Program conducted a study to determine the effects of urbanization on stream water quality and aquatic communities in six environmentally heterogeneous areas of the conterminous United States--Atlanta, Georgia; Raleigh-Durham, North Carolina; Milwaukee-Green Bay, Wisconsin; Dallas-Fort Worth, Texas; Denver, Colorado; and Portland, Oregon. This report compares and contrasts the response of stream chemistry during base flow to urbanization in different environmental settings and examines the relation between the exceedance of water-quality benchmarks and the level of urbanization in these areas. Chemical characteristics studied included concentrations of nutrients, dissolved pesticides, suspended sediment, sulfate, and chloride in base flow. In three study areas where the background land cover in minimally urbanized basins was predominantly forested (Atlanta, Raleigh-Durham, and Portland), urban development was associated with increased concentrations of nitrogen and total herbicides in streams. In Portland, there was evidence of mixed agricultural and urban influences at sites with 20 to 50 percent urban land cover. In two study areas where agriculture was the predominant background land cover (Milwaukee-Green Bay and Dallas-Fort Worth), concentrations of nitrogen and herbicides were flat or decreasing as urbanization increased. In Denver, which had predominantly shrub/grass as background land cover, nitrogen concentrations were only weakly related to urbanization, and total herbicide concentrations did not show any clear pattern relative to land cover - perhaps because of extensive water management in the study area. In contrast, total insecticide concentrations increased with increasing urbanization in all six study areas, likely due to high use of insecticides in urban applications and, for some study areas, the proximity of urban land cover to the sampling sites. Phosphorus concentrations increased with urbanization only in Portland; in Atlanta and Raleigh-Durham, leachate from septic tanks may have increased phosphorus concentrations in basins with minimal urban development. Concentrations of suspended sediment were only weakly associated with urbanization, probably because this study analyzed only base-flow samples, and the bulk of sediment loads to streams is transported in storm runoff rather than base flow. Sulfate and chloride concentrations increased with increasing urbanization in four study areas (Atlanta, Raleigh-Durham, Milwaukee-Green Bay, and Portland), likely due to increasing contributions from urban sources of these constituents. The weak relation between sulfate and chloride concentrations and urbanization in Dallas-Fort Worth and Denver was likely due in part to high sulfate and chloride concentrations in ground-water inflow, which would have obscured any pattern of increasing concentration with urbanization. Pesticides often were detected at multiple sites within a study area, so that the pesticide 'signature' for a given study area - the mixtures of pesticides detected, and their relative concentrations, at streams within the study area - tended to show some pesticides as dominant. The type and concentrations of the dominant pesticides varied markedly among sites within a study area. There were differences between pesticide signatures during high and low base-flow conditions in five of the six study areas. Normalization of absolute pesticide concentrations by the pesticide toxicity index (a relative index indicating potential toxicity to aquatic organisms) dramatically changed the pesticide signatures, indicating that the pesticides with the greatest potential to adversely affect cladocerans or fish were not necessarily the pesticides detected at the highest concentrations. In a screening-level assessment, measured contaminant concentrations in individual base-flow water samples were compared with various water-qual

Scientific Investigations Report↗

USGS2007

Review of Selected Documents Related to Flooding at City of Salisbury Facilities on the Yadkin River Upstream from High Rock Dam, North Carolina, September 2007

This report documents a review of the hydraulic and sediment-transport models developed by the City of Salisbury, Alcoa Power Generating, Inc., and the Federal Energy Regulatory Commission to address issues of flooding and sedimentation in the vicinity of Salisbury's water-supply intake 19.4 miles upstream from High Rock Dam. The objective of the review was to determine if the modeling results submitted by Salisbury clearly demonstrate that the presence of High Rock Dam has led to an increase in water levels at Salisbury facilities or, conversely, if the documents of Alcoa Power Generating, Inc., demonstrate that High Rock Dam has not had an effect on water levels at Salisbury facilities. No new data were collected as a part of the review, and the models developed by involved parties were not tested during the review. Some historical discharge-measurement notes and previously published reports were checked as part of the review. The one-dimensional hydraulic modeling results submitted by Alcoa Power Generating, Inc., did not assess the effects of changes in bathymetry on changes in flood levels at Salisbury's facilities because pre-impoundment conditions were not simulated. Hydraulic modeling performed by consultants for the City of Salisbury seems to indicate that both the presence of the dam in the absence of any post-impoundment sedimentation and changes in bathymetry between pre-impoundment and 1997 conditions have resulted in increased water levels relative to pre-impoundment conditions at Salisbury facilities on the Yadkin River for a fairly wide range of flows. The degree to which the dam and the changes in bathymetry have affected flood levels at the Salisbury facilities relative to pre-impoundment conditions is open to discussion because of uncertainty in topographic/bathymetric data and the absence of calibration and sensitivity testing of the hydraulic models. None of the three hydraulic models appears to have been calibrated to or tested against measurements, and no sensitivity testing was reported. Sediment-transport modeling results submitted by the City of Salisbury were calibrated, well documented, and provide a good understanding of the expected growth of the sediment delta in the upper end of High Rock Lake. Simulations made using this model seem to have demonstrated that the presence of the dam and the growth of the delta have resulted in increases in water-surface elevations at Salisbury's facilities over a range of flows and that these increases are expected to increase through time if current conditions remain unchanged.

Open-File Report↗

USGS2012

Groundwater, surface-water, and water-chemistry data from C-aquifer monitoring program, northeastern Arizona, 2005-11

The C aquifer is a regionally extensive multiple-aquifer system supplying water for municipal, agricultural, and industrial use in northeastern Arizona, northwestern New Mexico, and southeastern Utah. An increase in groundwater withdrawals from the C aquifer coupled with ongoing drought conditions in the study area increase the potential for drawdown within the aquifer. A decrease in the water table and potentiometric surface of C aquifer is illustrated locally by the drying up of Obed Meadows, a natural peat deposit, and Hugo Meadows, a natural wetland, both south of Joseph City, Arizona. Continual increase in water use from the C aquifer, including a planned increase in pumpage by the City of Flagstaff, is justification for continued monitoring of the C-aquifer system in order to quantify physical and chemical responses to pumping stresses. Fifteen of the 35 C-aquifer wells analyzed had water-level data sufficient for percentage difference calculation for 2005–11. Change in water level as a percentage of the initial water-level measurement for these 15 wells ranged from about -0.2 to about -0.5 percent. For historical water-level data, changes in water levels were greatest around pumping centers, as indicated by a -97.0 feet (percentage difference of -16.5 percent) change over the period of record (1962–2005) for the Lake Mary 1 Well near Flagstaff, Arizona. In more rural areas of the C aquifer, water levels showed less change for both the temporal focus of this report (2005–11) and for historical values. Continuous records of surface-water discharge from 2005 to 2007 for three discontinued streamflow-gaging stations (Clear Creek near Winslow, AZ, 09399000; Clear Creek below McHood Lake near Winslow, AZ, 09399100; and Chevelon Creek near Winslow, AZ, 09398000) were tabulated. For the period of record, Clear Creek near Winslow, AZ, and Chevelon Creek near Winslow, AZ, showed seasonal discharge distributions indicative of natural streams in the southwestern United States. Clear Creek below McHood Lake near Winslow, AZ, showed discharge distribution indicative of perennial spring flow with little variation annually. Physical and chemical data collected during four baseflow investigations (summer 2005, summer 2006, summer 2008, and winter 2010) conducted on Clear Creek, Chevelon Creek, and a portion of the Little Colorado River were compiled and analyzed. Data from 7 sampling sites established on the Little Colorado River, 11 sites along Chevelon Creek, and 14 sites along Clear Creek were included. For the four baseflow investigations presented, a 2,000–3,000 microsiemens per centimeter increase in specific conductance was measured in Chevelon Creek from near its headwaters to the confluence with the Little Colorado River because of the contribution of highly conductive spring discharge. Clear Creek showed a less consistent pattern of increase in specific conductance with distance, but still exhibited changes on the order of 5,000 microsiemens per centimeter over just a few river miles. Water-chemistry data for selected wells and baseflow investigations sites are presented. No well samples analyzed exceeded the U.S. Environmental Protection Agency Maximum Contaminant Level standards for drinking water, but several samples exceeded Secondary Maximum Contaminant Level standards for chloride, fluoride, sulfate, iron, and total dissolved solids.

Arizona↗

USGS1985

Pesticides in the nation's rivers, 1975-1980, and implications for future monitoring

Water samples were taken four times per year and bed-sediment samples two times per year during 1975-80 at 160 to 180 stations on major rivers of the United States. Samples were analyzed for 18 insecticides and 4 herbicides, which together accounted for about one-third of the total amount of all pesticides applied to major crops during 1975-80. Fewer than 10 percent of almost 3,000 water samples and fewer than 20 percent of almost 1,000 bed-sediment samples contained reportable concentrations of any of the compounds. The patterns of detection result from a combination of widely variable detection capabilities, chemical properties, and use. Most detections in water samples were of relatively persistent yet soluble compounds: atrazine (4.8 percent of samples), diazinon (1.2), and lindane (1.1). Most detections in bed-sediment samples were of the hydrophobic and persistent insecticides: DDE (17 percent of samples), DDD (12), dieldrin (12), chlordane (9.9), and DDT (8.5). Only for atrazine in water, and for DDE, DDD, DDT, and chlordane in bed sediments, were geographic patterns of detection correlated (pH<0.10) with use on farms. Detections of organochlorine insecticides in both water and bed sediments appear to have erratically but gradually decreased during 1975-80. For the 1975-79 period, more stations had downtrends than had uptrends in bed-sediment levels of organochlorines. No clear trends were evident in concentrations of organophosphate insecticides or herbicides in either water or bed sediments. Findings suggest that future pesticide monitoring efforts must be responsive to changes in pesticides used and to geographic patterns of use. Different types of monitoring approaches are necesssary for chemicals having different chemical and physical properties. Before an effective dynamic monitoring effort can be designed, however, selected case studies are needed to characterize and refine sampling and analytical capabilities for different types of chemicals, river environments, and sample types.

Water Supply Paper↗

USGS2013

Investigating the effects of point source and nonpoint source pollution on the water quality of the East River (Dongjiang) in South China

Understanding the physical processes of point source (PS) and nonpoint source (NPS) pollution is critical to evaluate river water quality and identify major pollutant sources in a watershed. In this study, we used the physically-based hydrological/water quality model, Soil and Water Assessment Tool, to investigate the influence of PS and NPS pollution on the water quality of the East River (Dongjiang in Chinese) in southern China. Our results indicate that NPS pollution was the dominant contribution (>94%) to nutrient loads except for mineral phosphorus (50%). A comprehensive Water Quality Index (WQI) computed using eight key water quality variables demonstrates that water quality is better upstream than downstream despite the higher level of ammonium nitrogen found in upstream waters. Also, the temporal (seasonal) and spatial distributions of nutrient loads clearly indicate the critical time period (from late dry season to early wet season) and pollution source areas within the basin (middle and downstream agricultural lands), which resource managers can use to accomplish substantial reduction of NPS pollutant loadings. Overall, this study helps our understanding of the relationship between human activities and pollutant loads and further contributes to decision support for local watershed managers to protect water quality in this region. In particular, the methods presented such as integrating WQI with watershed modeling and identifying the critical time period and pollutions source areas can be valuable for other researchers worldwide.

Dongjiang↗

USGS1982

Water-quality and hydrogeologic data for three phosphate industry waste-disposal sites in central Florida, 1979-80

This report is a complilation of geologic, hydrologic, and water-quality data and information on test holes collected in the vicinity of gypsum stack complexes at two phosphate chemical plants and one phosphatic clayey waste disposal pond at a phosphate mine and beneficiation plant in central Florida. The data were collected from September 1979 to October 1980 at thee AMAX Phosphate, Inc., chemical plant, Piney Point; the USS AgriChemicals chemical plant, Bartow; and the International Minerals and Chemical Corporation Clear Springs mine, Bartow. Approximmmtely 5,400 field and laboratory water-quality determinations on water samples were collected from about 78 test holes and 31 surface-water, rainfall, and other sampling sites at phosphate industry beneficiation and chemical plant waste-disposal operations. Maps show locations of sampling sites. (USGS)

Florida↗

USGS2019

Assessing causes of mortality for endangered juvenile Lost River suckers (Deltistes luxatus) in mesocosms in Upper Klamath Lake, south-central Oregon, 2016

Executive Summary The recovery of endangered Lost River suckers ( Deltistes luxatus ) in Upper Klamath Lake, south-central Oregon, has been impeded because juveniles are not recruiting into adult spawning populations. Adult sucker populations spawn each spring but mortality of age-0 suckers during their first summer is excessively high, and recruitment of juveniles into adult populations does not occur in most years. The last significant year class to join spawning aggregations was hatched in 1991. Capture rates for age-0 Lost River suckers decrease so substantially each summer that it is thought that mortality is nearly 100 percent within the first year of life each year. Causes of mortality are not understood but poor water quality, parasites, disease, predation, and non-native species are suspected to contribute to mortality. Upper Klamath Lake is hypereutrophic and summer water-quality conditions have large diurnal and seasonal fluctuations. Photosynthesis of Aphanizomenon flos-aquae , the most abundant cyanobacterium in Upper Klamath Lake, is responsible for large fluctuations in dissolved-oxygen (DO) concentrations and pH. We introduced hatchery-raised, passive integrated transponder-tagged juvenile Lost River suckers into large mesocosms located at Fish Banks, Mid North, and Rattlesnake Point in Upper Klamath Lake, Oregon, to assess sucker mortality relative to water-quality conditions. We identified the date of death for each sucker by assessing movement patterns among vertically stratified antennas. We modeled daily mortality using known fate models relative to water-quality conditions measured by sondes. Histopathology was used to understand causes of eminent mortality for moribund suckers. Fish mortality, growth, health, and movement patterns varied among locations, but it was unclear whether this variation was due to water-quality or other factors. Seasonal mortality was 58.8 percent at Fish Banks, 27.4 percent at Mid North, and 11.5 percent at Rattlesnake Point. Growth over the 109-day study period was lowest at Fish Banks (34.5 ±10.0 millimeters [mm] standard length (SL); 18.6 ±7.7 grams [g]), intermediate at Mid North (57.5 ±13.6 mm SL; 40.1 ±15.4 g), and greatest at Rattlesnake Point (78.4 ±13.0 mm SL; 72.5 ±18.7 g). Our ability to assess causes of juvenile sucker mortality in mesocosms using our modelling approach was limited by low daily mortality. Zero to 3 mortalities occurred per day, except on July 30 at Fish Banks when 7 mortalities occurred. Relative to any other measured and tested water-quality condition, mortality was more likely to occur on days with large fluctuations in oxygen percent saturation. When we assessed the fit of the most parsimonious model, performance was poor, which suggested that other factors were contributing to mortality. Our ability to assess the relationship between seasonal patterns in water quality and fish mortality were limited by the absence of substantial differences in water quality among sites, inconsistency in the depth at which measurements were collected, and no clear pattern in conditions leading up to and during mortality events. Except for DO at Rattlesnake Point and diel temperature variations at Fish Banks, seasonally summarized water-quality factors were similar among sites. The locations of water-quality monitors within the water column likely explain the differences in DO at Rattlesnake Point and temperature variation at Fish Banks. Furthermore, DO concentrations and other water-quality factors occurring during and prior to mortality events were inconsistent. Microscopic assessments indicated severe gill hyperplasia, fusion of the secondary lamellae, and severe Ichthyobodo sp. infestations on the gills of most moribund suckers. Liver glycogen was usually depleted in suckers with severe Ichthyobodo sp. infestations. Ichthyobodo sp. infestations probably were the immediate cause of death and probably originated from the Klamath Tribes Fish Research Facility, although this parasite also is present in Upper Klamath Lake and severe water-quality conditions may have contributed to morbidity. As suckers in the mesocosms died, they were replaced with suckers from the Fish Research Facility that likely were heavily parasitized with Ichthyobodo sp. Therefore, it is possible that the gradient in mortality rate among sites was owing to site-varying differences in inadvertent increases in introduced parasite loads.

Oregon↗

USGS1978

Management of flood-plain vegetation, 1967 to 1972, San Carlos Indian Reservation, Arizona

During 1967-71, 15,800 acres of flood-plain vegetation were cleared from a 26-mile reach of the Gila River valley and a 9-mile reach of the San Carlos River valley. Both areas are on the San Carlos Apache Indian Reservation, Arizona. The area cleared in the Gila River valley included the Gila River Phreatophyte Project and the clearing was conducted as prescribed by the experimental design of that research program. Establishment of replacement vegetation was attempted on the cleared areas with indifferent success. The report outlines methods used to remove the vegetation and to discourage its subsequent regrowth. Costs of the clearing operation are given by vegetation type, and descriptions of the procedures used for establishing new vegetation are given. Clearing and subsequent maintenance of parts of the flood plain were hampered by channel clogging and subsequent flooding of adjacent areas. Part of the area selected for clearing lies within the San Carlos Reservoir. The wide range of water level in the reservoir further aggravated maintenance of an inflow channel. Both draglines and a dredge were used to open a channel to the reservoir. Because the flow of the Gila River is intermittent, vegetation becomes established in the channel at the head of the reservoir during periods of no flow. The report concludes that the presence of the vegetation promotes silt deposition and further clogging. Inflow channel maintenance is a persistent problem that will require well-planned repetitive clearing of vegetation at the head of the reservoir.

Arizona↗

USGS1999

The economic value of Trinity River water

The Trinity River, largest tributary of the Klamath River, has its head-waters in the Trinity Alps of north-central California. After the construction of Trinity Dam in 1963, 90% of the Trinity River flow at Lewiston was moved to the Sacramento River via the Clear Creek Tunnel, a manmade conduit. Hydropower is produced at four installations along the route of Trinity River water that is diverted to the Sacramento River, and power production at three of these installations would diminish if no Trinity River water were diverted to the Sacramento River. After Trinity River water reaches the Sacramento River, it flows toward the Sacramento-San Joaquin Delta and San Francisco Bay. Trinity River water is pumped via Bureau of Reclamation canals and pumps to the northern San Joaquin Valley, where it is used for irrigated agriculture. The social cost of putting more water down the Trinity River is the sum of the value of the foregone consumer surplus from hydropower production as well as the value of the foregone irrigation water. Sharply diminished instream flows have also severely affected the size and robustness of Trinity River salmon, steelhead, shad and sturgeon runs. Survey data were used to estimate the non-market benefits of augmenting Trinity River instream flows by letting more water flow down the Trinity and moving less water to the Sacramento River. Preservation benefits for Trinity River instream flows and fish runs are $803 million per annum for the scenario that returns the most water down the Trinity River, a value that greatly exceeds the social cost estimate.The Trinity River, largest tributary of the Klamath River, has its headwaters in the Trinity Alps of north-central California. After the construction of Trinity Dam in 1963, 90% of the Trinity River flow at Lewiston was moved to the Sacramento River via the Clear Creek Tunnel, a manmade conduit. Hydropower is produced at four installations along the route of Trinity River water that is diverted to the Sacramento River, and power production at three of these installations would diminish if no Trinity River water were diverted to the Sacramento River. After Trinity River water reaches the Sacramento River, it flows toward the Sacramento-San Joaquin Delta and San Francisco Bay. Trinity River water is pumped via Bureau of Reclamation canals and pumps to the northern San Joaquin Valley, where it is used for irrigated agriculture. The social cost of putting more water down the Trinity River is the sum of the value of the foregone consumer surplus from hydropower production as well as the value of the foregone irrigation water. Sharply diminished instream flows have also severely affected the size and robustness of Trinity River salmon, steelhead, shad and sturgeon runs. Survey data were used to estimate the non-market benefits of augmenting Trinity River instream flows by letting more water flow down the Trinity and moving less water to the Sacramento River. Preservation benefits for Trinity River instream flows and fish runs are $803 million per annum for the scenario that returns the most water down the Trinity River, a value that greatly exceeds the social cost estimate.

International Journal of Water Resources Developme↗

USGS2022

Growth, survival, and cohort formation of juvenile Lost River (Deltistes luxatus) and shortnose suckers (Chasmistes brevirostris) in Upper Klamath Lake, Oregon, and Clear Lake Reservoir, California—2020 monitoring report

Executive Summary Populations of federally endangered Lost River ( Deltistes luxatus ) and shortnose suckers ( Chasmistes brevirostris ) in Upper Klamath Lake, Oregon, and Clear Lake Reservoir (hereinafter, Clear Lake), California, are experiencing long-term decreases in abundance. Upper Klamath Lake populations are decreasing not only because of adult mortality, which is relatively low, but also because they are not being balanced by recruitment of young adult suckers into known adult spawning aggregations. Long-term monitoring of juvenile sucker populations is conducted to (1) determine if there are annual and species-specific differences in production, survival, and growth, (2) better understand when juvenile sucker mortality is greatest, and (3) help identify potential causes of high juvenile sucker mortality particularly in Upper Klamath Lake. The U.S. Geological Survey (USGS) monitoring program, begun in 2015, tracks cohorts through summer months and among years in Upper Klamath and Clear Lakes. Data on juvenile suckers captured in trap nets are used to provide information on annual variability in age-0 sucker apparent production, juvenile sucker apparent survival, apparent growth, species composition, and health. Upper Klamath Lake indices of year-class strength suggest that the 2020 age-0 cohort is one of the lowest since standardized monitoring began. Despite apparently low over-winter survival, the relatively large 2019 cohort persisted in our 2020 samples and continues to contribute to the populations. Although the 2019 cohort age-0 suckers were composed mainly of Lost River suckers, the age-1 suckers from the 2019 cohort were mainly shortnose suckers. Lost River suckers comprised the largest proportion of the 2020 year-class and were only captured in July and August. Shortnose suckers were mainly captured in August and September and comprised a smaller proportion of the 2020 year-class. Age distribution of suckers captured in Clear Lake indicates greater juvenile survival than in Upper Klamath Lake. Most juvenile suckers captured were age-3 and age-4 suckers classified as the combination of Klamath largescale suckers ( Catostomus snyderi ) and shortnose suckers from the Lost River Basin, from the 2016 and 2017 cohorts. A lack of age-0 suckers captured in Clear Lake during years with the low inflow or lake levels initially lead us to believe that low water prevented spawning and year class formation. However, recent data indicate that some cohorts that were not captured as age-0 suckers were detected in later years at age-1 or age-2. This finding indicates that juvenile suckers in Clear Lake may spend one or more years in the tributaries or that sampling efficacy for age-0 suckers varies among years because of water depth. The first 5 years of this monitoring program indicated different patterns in recruitment and survival of juvenile suckers between Upper Klamath and Clear Lakes. Since the monitoring program began in 2015, age-0 sucker catch rates, interpreted as indices of year-class strength, were greatest in Upper Klamath Lake in 2016 and 2019. In those years Lost River suckers made up the majority of age-0 sucker catches; however, in 2017 and 2020 the age-1 sucker catches from these cohorts were mainly composed of shortnose suckers or suckers with genetic markers of both Klamath largescale and shortnose suckers, indicating a low overwinter survival for Lost River suckers even when the age-0 catches were high. Age-0 suckers do not fully recruit to our sampling gear in Upper Klamath Lake until August, experience high mortality by September, and are almost undetectable by the following July or August in most years. In Clear Lake, suckers frequently are not captured until age-1 or age-2 and annual survival appears much greater.

California, Oregon↗

USGS1985

Hydrology of Lake Placid and adjacent area, Highlands County, Florida

The study conducted during 1982-83, documents hydrologic conditions in Lake Placid and surrounding areas of Florida. Lake-stage data indicate that the 2- to 50-year flood stage ranges from 93.9 to 96.2 ft. Lake stage is reflected by annual departure of precipitation of the previous year from long-term average. A bathymetric map at 5 ft intervals indicates sinks in the lake bottom. Maximum depth and volume were 54 ft and more than 85,000 acre-feet, respectively. Lake Placid is a surface expression of the water table surficial aquifer with normal flow direction from south to north. Above average amounts of precipitation during winter 1983 created a groundwater mound north of Mirror Lake that caused reversal of the groundwater gradient in the water table aquifer. Lake water is neutral to slightly acidic, with low alkalinity and salinity. Nutrient concentrations are low and remain constant since 1966. Water samples collected since 1966 show trends toward increasing ionic composition and dissolved solids. Organic, inorganic, and phytoplankton analyses show Lake Placid to be relatively clear and clean. (USGS)

Water-Resources Investigations Report↗

USGS2011

Seasonal distribution, aggregation, and habitat selection of common carp in Clear Lake, Iowa

The common carp Cyprinus carpio is widely distributed and frequently considered a nuisance species outside its native range. Common carp are abundant in Clear Lake, Iowa, where their presence is both a symptom of degradation and an impediment to improving water quality and the sport fishery. We used radiotelemetry to quantify seasonal distribution, aggregation, and habitat selection of adult and subadult common carp in Clear Lake during 2005-2006 in an effort to guide future control strategies. Over a 22-month period, we recorded 1,951 locations of 54 adults and 60 subadults implanted with radio transmitters. Adults demonstrated a clear tendency to aggregate in an offshore area during the late fall and winter and in shallow, vegetated areas before and during spring spawning. Late-fall and winter aggregations were estimated to include a larger percentage of the tracked adults than spring aggregations. Subadults aggregated in shallow, vegetated areas during the spring and early summer. Our study, when considered in combination with previous research, suggests repeatable patterns of distribution, aggregation, and habitat selection that should facilitate common carp reduction programs in Clear Lake and similar systems. ?? Copyright by the American Fisheries Society 2008.

Transactions of the American Fisheries Society↗

USGS2005

Stream acidification and mortality of brook trout (Salvelinus fontinalis) in response to timber harvest in Catskill Mountain watersheds, New York, USA

Effects of clear-cut and timber-stand improvement (TSI) harvests on water chemistry and mortality of caged brook trout (Salvelinus fontinalis) were evaluated in a study of three Catskill Mountain streams, 1994-2000. Harvests removed 73% of tree basal area (BA) from a clearcut subbasin, 5% BA from a TSI subbasin, and 14% BA at a site below the confluence of both streams. A fourth nonharvested site served as a control. Water quality and trout mortality were affected only in the clearcut stream. Acidity and concentrations of nitrate and inorganic monomeric aluminum (Alim) increased sharply during high flows after the first growing season (fall 1997). Acid-Alim episodes were severe during this period and decreased steadily in magnitude and duration thereafter. All trout at this site died within 7 days during spring 1998 and 85% died during spring 1999. Only background mortality was observed in other years at this site and at the other three sites during all tests. The absence of mortality in TSI watersheds indicates that limited harvests should not harm brook trout populations in acid-sensitive streams. Effects of tree harvests on fish communities are of concern, however, because many stream-dwelling species are more sensitive to acidified waters than brook trout. ?? 2005 NRC.

Canadian Journal of Fisheries and Aquatic Sciences↗