A taxonomic review of the American long-tailed shrews (genera Sorex and Microsorex)
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North American Fauna↗
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Water sediment, and nutrient budgets, and bathymetric survey of Old and New Gillespie Lakes, Macoupin County, Illinois, May 1996-April 1997; with a discussion of lake-management practices
The Gillespie Lakes system serves as a drinking water source for the town of Gillespie, Illinois, and is a major recreational focus for the area. As part of an investigation of a concern that the lakes are being adversely affected by excessive sediment and nutrient in flows, this report presents hydrologic, sediment, and nutrient budgets for Old Gillespie Lake and New Gillespie Lake, calculated by the U.S. Geological Survey with data collected during May 1996-April 1997 in cooperation with the Illinois Environmental Protection Agency and the city of Gillespie, Illinois. Bathymetric data also were collected in the two lakes to produce maps of the lake bed elevations. The influx of sediment, phosphorus, and nitrogen into Old Gillespie Lake during the study period was 4,063, 6.02, and 52.3 tons, respectively. Old Gillespie Lake retained 92 percent of the inflowing sediment (which agrees with theoretical calculations of trapping efficiency for Old Gillespie Lake), 84 percent of the inflowing phosphorus, and 87 percent of the inflowing nitrogen. The influx of sediment, phosphorus, and nitrogen into New Gillespie Lake during the study period was 4,792, 7.56, and 64.3 tons, respectively. Old Gillespie Lake retained 95 percent of the inflowing sediment (which agrees with theoretical calculations of trapping efficiency for New Gillespie Lake), 82 percent of the inflowing phosphorus, and 81 percent of the inflowing nitrogen. The loads per area of phosphorus and nitrogen to the Gillespie Lakes were 1.06 tons/mi 2 and 9.26 tons/mi 2 , respectively. For row crops of corn and soybeans, the literature reports ranges of loads per area of phosphorus of 0.15 to 1.43 tons/mi 2 and of nitrogen of 0.86 to 11.43 tons/mi 2 . Therefore, loads to the Gillespie Lakes are relatively high for the given cropping practices, and application of best management practices may substantially reduce the per area loads of these nutrients. Considering these loads and retention of sediment and nutrients, a review of basic lake management practices is presented and discussed. This review is presented to assist lake managers in the achievement of lake water-quality goals.
Macoupin County↗
Geologic map of the Domeland Wilderness and contiguous roadless area, Kern and Tulare counties, California
The Wilderness Act (Public Law 88-577, September 3, 1964) and related acts require the U.S. Geological Survey and the U.S. Bureau of Mines to survey certain areas on Federal lands to determine their mineral-resource potential. Results must be made available to the public and be submitted to the President and the Congress. This report presents the results of a geologic survey of the Domeland Wilderness and contiguous roadless areas in the Sequoia National Forest, Kern and Tulare Counties, California. The Domeland Wilderness was established by Public Law 88-577 (1964). The Woodpecker Roadless Area (05206) and the Domeland Addition Roadless Areas (05207) were classified as further planning areas during the Second Roadless Area Review and Evaluation (RARE II) by the U.S. Forest Service, January 1979.
California↗
Observing systems, modeling, and forecasting
Predicting harmful algal blooms (HABs) requires integrating physical, chemical, and biological data collected from observing networks and then assimilating these data into models, which are used to generate forecasts. In 2005, the Harmful Algal Research and Response: A National Environmental Science Strategy 2005-2015 (HARRNESS, 2005) made recommendations on how to improve HAB modeling and forecasting over the next decade. Key HARRNESS recommendations related to sensing, networking, and modeling HABs included: ● Support the development and validation of new and improved technologies for remote cell and toxin detection, and for modeling and forecasting, ● Improve coordination of monitoring/ and modeling efforts, both at national and regional levels, ● Improve the use of networking technologies for monitoring and modeling efforts, ● Conduct sustained time series measurements of the biotic, chemical, and physical environments impacted by HABs, ● Develop food web models on the ecosystem fate and effects of toxins, ● Develop and improve species-specific models that link to physical-biological models. Here we review HAB observing, modeling, and forecasting advances and technologies and recommend research and management priorities for the next decade and beyond. Our report encompasses sensing technologies, sensor networking and data management, models and forecasts, and the paths to operationalize forecasts. Continued improvements of deployable sensors are foundational to improving early warning indicators, models, and forecasts, which are only as good as the underlying data. Sensing technology has advanced considerably in the last decade; for example, more capable fluorometric pigment sensors can track changes in bloom biomass in real-time. Additionally, automated imaging/classifying systems to identify and quantify key harmful algal (HA) taxa are being routinely deployed. However, deployable toxin sensors are available for only some HAB toxins and continue to be identified as a critical need by researchers and managers. As more and improved sensors and technologies become available, the data quality associated with each sensor needs to be assessed. Data quality encompasses the reliability, accuracy, and uncertainty associated with sensor-generated data. These data need to be of known quality so that researchers, managers, and end-users can reliably determine if the information is appropriate for their intended applications. Many of the data quality recommendations from HARRNESS (2005) are still relevant and have been reiterated within the management community. Understanding and documenting data quality, and when applicable, standardizing best practices for sensor use, continue to be recommended.
Report↗
Geology of possible petroleum provinces in Alaska
The history of petroleum exploration in Alaska and the geology of possible petroleum provinces in Alaska are reviewed. Maps showing Alaska's major Mesozoic and Tertiary tectonic elements, possible petroleum provinces, and indications of petrol, are included in this report. Annotated references in Geological Survey publications relating to petroleum and oil shale in Alaska are given at the end of the report. For the purpose of appraising its petroleum possibilities, Alaska is divided into the southern, central, and northern major geologic-physiographic regions. Southern Alaska includes the arcuate mountain chain formed by the Alaska and Aleutian Ranges and the Mentasta- Nutzotin Mountains, the coastal range and valley area to the south, and the southeastern Alaska "panhandle" -- an area of 185,000 square miles. Oil seeps on the west shore of Cook Inlet in southern Alaska were known as early as 1853, and claims were staked in this region in 1882. Drilling began near the oil seeps in the Katalla district about 1901, and this started Alaska's first period of oil activity. From 1902 to 1933 the Katalla field produced 154,000 barrels of oil from fractured shale and sandstone of Tertiary age the- first and only commercial production in Alaska. On the basis of geology, surficial indications of petroleum, and test wells drilled, six possible petroleum provinces are indicated in southern Alaska. They are Heceta Island area, Keku Islands area, Cook Inlet Mesozoic province, Gulf of Alaska Tertiary province, Cook Inlet Tertiary province, and Copper River basin. The exposed rocks in the Heceta Island area include lower Paleozoic graywacke-type sandstone, sandstone, conglomerate, and massive limestones with reeflike structures; igneous rocks are rare or lacking in much of the area. The Kosciusko-Tuxekan-Heceta synclinorium, the main structural feature, is modified by minor folds and faults. Some of the minor folds are reported to be broad and open, with flanks dipping 20°-145°. As far as known, the Heceta Island area has not heretofore been seriously considered as a possible petroleum province. Rocks of Silurian to Cretaceous age are exposed in the Keku Island area and include moderately folded and relatively unaltered limestone and other marine sedimentary rocks. The Cook Inlet Mesozoic province, a land area of approximately 18,500 square miles, includes a great thickness of unmetamorphosed marine sedimentary rocks of Jurassic and Cretaceous age. At least 23 test wells were drilled or started in this province by the end of 1955. Shows of oil and gas were encountered in many of these wells. During 1955 at least ten oil companies were active in this area and by the end of 1955 about 1 1/2 million acres were included in oil and gas leases applied for or granted. The Gulf of Alaska Tertiary province includes about 5,200 square miles in which rocks of Tertiary age are exposed or are believed to underlie Quaternary deposits. Between 1901 and the end of 1955 about 47 wells were drilled or started in this province. The Cook Inlet Tertiary province embraces an area of about 9,500 square miles, of which about 4,100 is covered by the shallow waters of Cook Inlet. Petroleum exploration has been in that part of the area which overlaps the Cook Inlet Mesozoic province. Eocene or younger Tertiary nonmarine sedimentary rocks are believed to underlie much of the province, and marine rocks of Tertiary age may also be present. The Copper River basin is a topographic basin underlain by unconsolidated deposits of Quaternary age. Tertiary rocks favorable for the accumulation of petroleum may underlie part of the basin but this is not believed likely. Except for some leasing activity no petroleum exploration has been recorded in the Copper River Basin to the end of 1955. Central Alaska is a region of about 275,000 square miles and consists of an irregular assemblage of intricately dissected uplands and alluvium-floored lowland basins. Scattered peaks of resistant intrusive igneous rocks surmount most of the upland areas. In the vast region of central Alaska only six test wells are known to have been drilled for the purpose of finding oil and gas. The maximum depth reached was 350 feet and the holes were mostly or entirely in Quaternary deposits. In recent years several oil companies have investigated some parts of the region and large areas in the Yukon-Koyukuk province are now under lease. Oil seeps, gas seeps, and other indications of petroleum have been reported from many localities; samples from two localities have been analyzed and reported to be petroleum. The geology of central Alaska is similar in a general way to that of the area between the Rocky Mountains and Sierra-Cascade belts of the United States. Sedimentary rocks, probably equivalent to the Precambrian Belt series, and rocks of the Cambrian and all younger geologic systems have been recognized in central Alaska. The structure of the region is known to be complex, but except in local mineral districts, it has not been mapped in detail. Based on the limited amount of available information, the region cannot be regarded as distinctly favorable for significant accumulations of petroleum. However, three pre-Cenozoic provinces, the Yukon-Koyukuk, the Kobuk, and the Kandik, and several large Cenozoic basin provinces may be worthy of further investigation. Northern Alaska includes the Brooks Range and all the treeless tundra north to the Arctic Coast, an area of about 125,000 square miles. The presence of oil seeps along the Arctic Coast has been known at least since 1900 and a description of the Cape Simpson oil seeps vas published in 1909. Since then oil and gas seeps have been described from nine localities, and oil shales and oil-bearing sandstones are known from many localities in the Arctic Foothills province. Oil and gas deposits have been discovered and geologic conditions are favorable for oil and gas accumulations in approximately half of the region. In 1923 approximately 37,000 square miles in northern Alaska was reserved by Executive order as Naval Petroleum Reserve No. 4. In 1944 the U. S. Navy began a vast petroleum exploration program which was suspended in 1953. In the years 1945 through 1955, 37 test wells and 45 core tests were drilled on 18 structures. Three oil fields, Umiat, Simpson, and Fish Creek, and two gas fields, South Barrow and Gubik, were discovered. Total reserve estimates for all discoveries of oil to 1955 range from 30 to 100 million barrels, and for gas, from 370 billion to 900 billion cubic feet. All northern Alaska, with the exception of the Brooks Range, can be considered a possible petroleum province, but the region can be subdivided into provinces of somewhat different potentialities. These subdivisions roughly correspond with the geomorphic provinces and sections, which in turn reflect differences in geology. The known oil-bearing beds are of Mesozoic age, primarily Cretaceous, and thus the possible petroleum provinces could be designated as Mesozoic. However, Paleozoic and Cenozoic rocks with favorable reservoir characteristics are exposed in the region and possibly underlie, in favorable structural situations, some of the areas as yet not tested. The Arctic Coastal Plain province includes gently folded and flat-lying Mesozoic beds that overlie a basement complex of Paleozoic and early Mesozoic age. Near the southern edge of this province the basement rocks are at depths of at least 20,000 feet, and to the north these rocks rise to within 2,500 feet of the surface. The Teshukpuk Lake section of the Arctic Coastal plain includes many of the known oil seeps; it is the most accessible to sea transportation, and lies almost completely within NPR 4. Thirteen test wells and 35 core tests have been drilled here; one gas field and two (at present, noncommercial) oil fields have been discovered. The possibility of further discoveries may depend largely on locating porous sandstones in stratigraphic rather than anticlinal traps. The White Hills section is distinguished topographically from the Teshukpruk section by its white-gravel-covered hills and fever lakes, and geologically by the presence of Tertiary rocks, including 2,000 feet of nonmarine beds in the west and at least 7,000 feet of marine beds to the east, in the vicinity of Carter Creek. This section appears to be more complex structurally. No test wells have been drilled in the White Hills section. The Northern Foothills section includes many closed anticlines. Twenty-four test wells and ten core tests have been drilled on 11 structures and two discoveries have been made -the Umiat oil field and the Gubik gas field. All these tests have been drilled in Cretaceous rocks. The Southern Foothills section is structurally similar to the Alberta Foothills and to the northern part of the Brooks Range. Great thicknesses of marine shale of Lover Cretaceous, Jurassic, and Triassic age are exposed. The outcropping Mesozoic sandstones are generally poorly sorted, nonporous, and impermeable. To the south the section is bordered by mountainous exposures of Mississippian limestone, which probably underlie at least part of this section. The rocks that underlie the deeply eroded complex structures of the Brooks Range include schist, slate, argillite, and limestone. Some exposed limestones have a strong petroleum-like odor and contain traces of petroleum residues.
Alaska↗
Positively selected genes in the hoary bat (Lasiurus cinereus) lineage: Prominence of thymus expression, immune and metabolic function, and regions of ancient synteny
Background Bats of the genus Lasiurus occur throughout the Americas and have diversified into at least 20 species among three subgenera. The hoary bat ( Lasiurus cinereus ) is highly migratory and ranges farther across North America than any other wild mammal. Despite the ecological importance of this species as a major insect predator, and the particular susceptibility of lasiurine bats to wind turbine strikes, our understanding of hoary bat ecology, physiology, and behavior remains poor. Methods To better understand adaptive evolution in this lineage, we used whole-genome sequencing to identify protein-coding sequence and explore signatures of positive selection. Gene models were predicted with Maker and compared to seven well-annotated and phylogenetically representative species. Evolutionary rate analysis was performed with PAML. Results Of 9,447 single-copy orthologous groups that met evaluation criteria, 150 genes had a significant excess of nonsynonymous substitutions along the L. cinereus branch ( P < 0.001 after manual review of alignments). Selected genes as a group had biased expression, most strongly in thymus tissue. We identified 23 selected genes with reported immune functions as well as a divergent paralog of Steep1 within suborder Yangochiroptera. Seventeen genes had roles in lipid and glucose metabolic pathways, partially overlapping with 15 mitochondrion-associated genes; these adaptations may reflect the metabolic challenges of hibernation, long-distance migration, and seasonal variation in prey abundance. The genomic distribution of positively selected genes differed significantly from background expectation by discrete Kolmogorov–Smirnov test ( P < 0.001). Remarkably, the top three physical clusters all coincided with islands of conserved synteny predating Mammalia, the largest of which shares synteny with the human cat-eye critical region (CECR) on 22q11. This observation coupled with the expansion of a novel Tbx1 -like gene family may indicate evolutionary innovation during pharyngeal arch development: both the CECR and Tbx1 cause dosage-dependent congenital abnormalities in thymus, heart, and head, and craniodysmorphy is associated with human orthologs of other positively selected genes as well.
PeerJ↗
Nutrients, phytoplankton, zooplankton, and macrobenthos
Lower trophic levels support the prey fish on which most sport fish depend. Therefore, understanding the production potential of lower trophic levels is integral to the management of Lake Ontario’s fishery resources. Lower trophic-level productivity differs among offshore and nearshore waters. In the offshore, there is concern about the ability of the lake to support Alewife (Table 1) production due to a perceived decline in productivity of phytoplankton and zooplankton whereas, in the nearshore, there is a concern about excessive attached algal production (e.g., Cladophora) associated with higher nutrient concentrations—the oligotrophication of the offshore and the eutrophication of the nearshore (Mills et al. 2003; Holeck et al. 2008; Dove 2009; Koops et al. 2015; Stewart et al. 2016). Even though the collapse of the Alewife population in Lake Huron in 2003 (and the associated decline in the Chinook Salmon fishery) may have been precipitated by a cold winter (Dunlop and Riley 2013), Alewife had not returned to high abundances in Lake Huron as of 2014 (Roseman et al. 2015). Failure of the Alewife population to recover from collapse has been attributed to declines in lower trophic-level production (Barbiero et al. 2011; Bunnell et al. 2014; but see He et al. 2015). In Lake Michigan, concerns of a similar Alewife collapse led to a decrease in the number of Chinook Salmon stocked. If lower trophic-level production declines in Lake Ontario, a similar management action could be considered. On the other hand, in Lake Erie, which supplies most of the water in Lake Ontario, eutrophication is increasing and so are harmful algal blooms. Thus, there is also a concern that nutrient levels and algal blooms could increase in Lake Ontario, especially in the nearshore. Solutions to the two processes of concern—eutrophication in the nearshore and oligotrophication in the offshore—may be mutually exclusive. In either circumstance, fisheries management needs information on the productivity of lower trophic levels in Lake Ontario. In this chapter, we review the status of lower trophic levels in Lake Ontario with special attention to the current (2008-2013) and previous (2003-2007) reporting periods. During the two reporting periods, three whole-lake surveys of lower trophic levels were conducted: the Lower Trophic Level Assessment (LOLA) in 2003 and 2008 (Makarewicz and Howell 2012; Munawar et al. 2015b) and the Cooperative Science and Management Initiative (CSMI) in 2013. Analyses of the CSMI data are ongoing. In addition to the three one-year sources of information on lower trophic levels, several multi-year sources of information are available, including data from the surveillance program conducted since 1965 by Environment Canada (EC) (Dove 2009), monitoring conducted since 1980 by the U.S. Environmental Protection Agency’s (EPA) Great Lakes National Program Office (GLNPO) (Barbiero et al. 2014; Reavie et al. 2014), sampling for a Bioindex Program at two stations, one offshore and one in the Eastern Basin, assessments of Mysis diluviana (formerly Mysis relicta) conducted since 1980 by Fisheries and Oceans Canada (Johannsson et al. 1998, 2011) and the Ontario Ministry of Natural Resources and Forestry (OMNRF), and monitoring conducted since 1995 by the Biomonitoring Program (BMP) on the New York side of the lake (Holeck et al. 2015b). The BMP is a collaboration of the New York State Department of Environmental Conservation (DEC), U.S. Fish and Wildlife Service, U.S. Geological Survey (USGS), and Cornell University.
Special Publication↗
Analysis of high-resolution single channel seismic data for use in sediment resource evaluation, eastern Texas and western Louisiana Continental Shelf, Gulf of Mexico
Shallow subsurface geologic data recorded as high-resolution seismic profiles are used to interpret the geology of coastal and marine systems. These data were originally recorded on paper rolls that are stored in geophysical archives. Data collection has since converted to entirely digital formats, yet the analog data are still useful for geologic interpretation. This report describes the process of recovering analog copies of seismic profiles from physical archives, electronically scanning, and converting them to industry-standard digital format. The recovered data are also reviewed and assessed for potential sediment resources. The data recovered in this study were collected from the Gulf of Mexico continental shelf offshore of East Texas and West Louisiana. The project is a collaborative study between the U.S. Geological Survey and the Bureau of Ocean Energy Management.
Louisiana, Texas↗
Bathymetric survey and physical and chemical-related properties of Raccourci Lake, Louisiana, July 1998 and April 1999
Raccourci Lake (Old River), an oxbow lake formed from an incomplete cutoff of the Mississippi River in southeast Louisiana, is a popular recreational lake used for water-based activities such as water skiing, fishing, boating, and swimming. The nearness of this large oxbow to Baton Rouge and its continued fishing productivity make it one of the most used lakes in southern Louisiana. An understanding of current hydrologic conditions of Raccourci Lake and other lakes and reservoirs in Louisiana is essential to the management and protection of these valuable natural resources. Water quality and quantity are important concerns to those who use these bodies of water for municipal, recreational, agricultural, or industrial purposes. Current and accurate information regarding the physical and chemical-related properties and conditions of freshwater lakes and reservoirs in Louisiana is fundamental to planners and managers for evaluating these resources. In October 1996, the U.S. Geological Survey, in cooperation with the Louisiana Department of Transportation and Development, began a study to conduct a bathymetric survey and determine the physical and chemical-related properties of Raccourci Lake. The purpose of this report is to present the results of the bathymetric survey and the results of vertical profiles of physical and chemical-related properties, including depth, water temperature, dissolved oxygen (DO), specific conductance, and pH, which were measured at three sites in the lake. Hydrographic surveying software was used for combining differential global positioning system (DGPS) information with digital survey fathometer data to accurately map the bathymetry of the lake. The bathymetric map was produced using geographic information systems (GIS), and lines of equal depth of water were reviewed and edited for accuracy and consistency. On-site physical and chemical-related properties were measured at the three selected locations using a water-quality monitor. This report is one in a series of planned map reports describing current bathymetry and physical and chemical-related properties of lakes and reservoirs in Louisiana.
Louisiana↗
Relative abundance, seasonal occurrence, and distribution of marine birds in the northern Gulf of Mexico
Marine birds in the U.S. Gulf of Mexico have long been poorly studied. Given statutory obligations to protect migratory birds and endangered species, three broad-scale vessel and aerial programs initiated since 2010 have now surveyed the entire northern Gulf. Vessel coverage alone exceeds 700 d and 74,000 km of observer effort using 300-m strip transects. We supplemented these survey data with earlier, smaller-scale studies, eBird checklists, literature reviews, and other less accessible sources to create snapshot summaries of relative abundance, seasonal occurrence, and regional distribution for 117 taxa of marine and water birds reported from the northern Gulf (113 of which were substantiated with physical evidence). Using taxonomic and functional criteria, we identified 56 taxa characteristic of open shelf, slope, and pelagic waters (federal jurisdiction), 41 taxa with primarily coastal affinities (state and federal jurisdiction), and 20 taxa of sea and diving ducks. High species richness of marine birds in the northern Gulf is attributed to (1) a temperate-to-tropical gradient facilitating diverse marine environments year-round; (2) varied geographic origins of marine bird species using the Gulf; and (3) a mostly enclosed sea basin acting as a vagrant trap for wide-ranging species. Our taxonomic list and status updates seek to bridge information gaps for marine birds now subject to accelerated commercial uses of this region's continental shelf, including newly proposed offshore wind energy development. Other applications include guiding risk and vulnerability assessments of Gulf marine birds, providing core content for seabird observer training, and prioritizing environmental impact reviews and monitoring programs in offshore energy construction and operations plans.
Marine Ornithology: Journal of Seabird Research an↗
Water-quality assessment of part of the Upper Mississippi River Basin, Minnesota and Wisconsin — Review of selected literature
The U.S. Geological Survey began full-scale implementation of the National Water-Quality Assessment (NAWQA) Program in 1991. The purposes of NAWQA are to describe the status and trends in the quality of the Nation's water resources and aquatic ecosystems, and to determine factors affecting water quality at local, regional, and national scales. The Upper Mississippi River (UMIS) NAWQA study unit, which includes all of the surface drainage to the Mississippi River Basin upstream from Lake Pepin, encompasses 47,000 mi 2 . The study characterizes the geographic and seasonal distribution of water quality and aquatic biota in relation to anthropogenic activities and natural features. The initial phase of the UMIS study, during 1994-99, is focused on an area in Minnesota and Wisconsin that includes the seven-county Twin Cities (Minneapolis and St. Paul) metropolitan area. This report summarizes selected sources of information that are being used to aid in understanding water-quality issues and processes that form the basis of the sampling design for the study. This literature review includes sources of information about surface- and ground-water hydrology, water quality, and aquatic biology and ecology.
Minnesota, Wisconsin↗
Acid precipitation; an annotated bibliography
This collection of 1660 bibliographies references on the causes and environmental effects of acidic atmospheric deposition was compiled from computerized literature searches of earth-science and chemistry data bases. Categories of information are (1) atmospheric chemistry (gases and aerosols), (2) precipitation chemistry, (3) transport and deposition (wet and dry), (4) aquatic environments (biological and hydrological), (5) terrestrial environments, (6) effects on materials and structures, (7) air and precipitation monitoring and data collection, and (8) modeling studies. References date from the late 1800 's through December 1981. The bibliography includes short summaries of most documents. Omitted are unpublished manuscripts, publications in press, master 's theses and doctoral dissertations, newspaper articles, and book reviews. Coauthors and subject indexes are included. (USGS)
Circular↗
Alien plant species threat assessment and management prioritization for Sequoia-Kings Canyon and Yosemite National Parks
Executive Summary This document reports the results of alien species surveys at Sequoia-Kings Canyon and Yosemite national parks. It includes the findings of a comprehensive literature review of the biology and ecology of all alien plant species found during these surveys and the ranking of those species for prioritizing management and control programs. Surveys primarily targeted areas of human disturbance, such as campgrounds, corrals, developments, roads, trails and pastures. Alien species richness was compared across elevational gradients within the parks. To compare and contrast species composition among sites, an exploratory cluster analysis of the sites included in the speciesrichness- by-elevation figures was conducted using ordination techniques. All alien species discovered during the directed surveys were grouped into one of four management priority categories based on their attributes, potential impacts, and geographical extent. Category 1 species are aliens that are currently restricted to a relatively small number of sites in each park and have either been shown to greatly affect native vegetation or have a high probability of causing serious impacts. Category 2 species are restricted to a relatively small number of sites and are ones that generally have a lesser effect on native vegetation. Category 3 species are broadly distributed in the parks, are apparently increasing their ranges within the parks, and are those that have been shown to have a great impact on native vegetation. Category 4 species are those that were detected by the surveys but not assigned to one of the three ranked categories and are considered low priority.
Open-File Report↗
A review of classical silicate-rock analysis and recommended modifications of classical methods of analysis
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Circular↗
Review of waterpower classifications and withdrawals, Deschutes River basin, Oregon
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Open-File Report↗
A review of the regional geology and tectonics of southeastern Alaska
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Open-File Report↗
A review and interpretation of the geologic setting of the Watchung Basalt flows, New Jersey
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Professional Paper↗