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This manual describes atomic-absorption-spectroscopy methods for determining calcium, copper, lithium, magnesium, manganese, potassium, sodium, strontium and zinc in atmospheric precipitation, fresh waters, and brines. The procedures are intended to be used by water quality laboratories of the Water Resources Division of the U.S. Geological Survey. Detailed procedures, calculations, and methods for the preparation of reagents are given for each element along with data on accuracy, precision, and sensitivity. Other topics discussed briefly are the principle of atomic absorption, instrumentation used, and special analytical techniques.
The herbicide atrazine (2chloro4ethylamino6isopropylamino1,3,5triazine) is the most heavily used agricultural pesticide in North America. Domestically, more than 50 million kg are applied yearly to more than 25 million ha, primarily to control weeds in corn and sorghum crops. Atrazine residues have been detected in runoff from treated fields in lakes and streams at phytotoxic levels. Birds and mammals were comparatively resistant, with a low probability for atrazine accumulation and retention. Data are lacking on indirect effects of atrazine on wildlife granivores and insectivores. Direct effects to aquatic fauna occur at 94 micrograms/l, and higher; however, indirect effects may occur at 20 micrograms/l, and higher, partly through reduction of the food supply of herbivores, and partly through loss of macrophyte habitat. Ecological and toxicological aspects of atrazine in the environment are briefly reviewed, with special emphasis on fishery and wildlife resources.
The subject of the geographical distribution and variation of our western zoölogy is one that has of late years attracted more than ordinary attention from our naturalists; and, as appropriate to the subject-matter of this volume, it is here proposed to give a brief résumé of their conclusions and generalizations, as far as they may be deemed applicable to the special natural history work of the geographical surveys west of the one hundredth meridian.
Information from 68 surface localities that I visited was used in the preparation of a report on the Cambrian and Ordovician rocks of Arizona, New Mexico, and western Texas (Hayes, 1975). Descriptions of the stratigraphic sequence at many of these localities have been published in various reports and a majority of those descriptions are reasonably good if not excellent. The rocks at some other localities are either so poorly exposed or faulted or altered that neither useful nor trustworthy sections are measurable there. Included herein are descriptions of part or all of the Cambrian and Ordovician sequence at three localities where the sections have not been described previously in the literature, at two localities whose excellent sections have previously been presented only in generalized graphic form, and at five localities whose previously published descriptions are at considerable variance with my observations in some way (fig. 1). It is doubtful if interest in any of these sections is sufficiently widespread at this time to justify formal publication of these descriptions but they are presented here for those few persons who may have special interest in them. Enclosed in parentheses following the name of each section is the locality number used in my published report (Hayes, 1975). Color terminology for the rocks are adapted from the Rock Color Chart. Bedding thicknesses, when not given in inches, are approximately as follows: thin-bedded for beds up to 6 inches thick, medium-bedded for beds 6 inches to 2 feet thick, thick-bedded for beds 2-5 feet thick; massive for beds more than 5 feet thick. All the sections in this report were measured with the capable assistance of George C. Cone. Fossil collections referred to in this report are described in Hayes (1975).
Water resources data for the 1998 water year for Pennsylvania consist of records of discharge and water quality of streams; contents and elevations of lakes and reservoirs; and water levels and water quality of ground-water wells. This report, Volume 1 contains (1) discharge records for 76 continuous-record streamflow-gaging stations, 5 partial record stations and 16 special study and miscellaneous streamflow sites; (2) elevation and contents records for 14 lakes and reservoirs; (3) water-quality records for 23 gaging stations and 44 ungaged streamsites; and (4) water-level records for 38 network observation wells; and (5) water-quality analyses of groundwater from 5 special-study ground-water wells. Site locations are shown in figures 6-9. Additional water data collected at various sites not involved in the systematic data-collection program are also presented. These data together with the data in Volumes 2 and 3, represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State, local, and Federal agencies in Pennsylvania.
Changes in riparian vegetation cover and composition occur in relation to flow regime, geomorphic template, and climate, and can have cascading effects on aquatic and terrestrial ecosystems. Tracking such changes over time is therefore an important part of monitoring the condition and trajectory of riparian ecosystems. Maintaining diverse, self-sustaining riparian vegetation comprised of mostly native species is identified in the Glen Canyon Dam Long-Term Experimental and Management Plan as a key resource objective for the section of the Colorado River between Glen Canyon Dam and Lake Mead. The U.S. Geological Survey Grand Canyon Monitoring and Research Center implemented an annual monitoring program in 2014 to assess the status and trends of riparian vegetation along this section of river, particularly as they relate to flow regime. In this report, we summarize plant species composition and cover data collected under the annual monitoring program from 2014 to 2019, with special consideration given to the hydrologic position, associated geomorphic feature class, local climate patterns, native and nonnative species, and floristic region for key vegetation metrics and species. We divided the study area into four river segments (referred to as Glen Canyon, Marble Canyon, eastern Grand Canyon, and western Grand Canyon) on the basis of geography and floristic composition and calculated each recorded plant species’ relative frequency and foliar cover by river segment. These data were then used to evaluate species composition relationships among river segments, hydrologic zones, geomorphic features, and sampling years through ordination analysis. Temporal trends in our focal resource objectives—species richness, total foliar cover, proportion of native to nonnative species richness, proportion of native to nonnative species cover, Tamarix cover, Pluchea sericea cover, and Baccharis species cover—were assessed using mixed-effects models. Four patterns related to species composition emerged: (1) species composition of fixed-site sandbars differed from that of randomly selected sites (including randomly selected sandbars), (2) species composition of Glen Canyon sites differed from that of other previously identified floristic regions, (3) species composition differed across hydrologic zones related to dam operations, and (4) species composition within river segments did not change across years. For temporal patterns, four main findings emerged: (1) trends differed between fixed-sites and randomly selected sites; (2) although few directional changes were observed from 2014 to 2019, Baccharis species cover increased at randomly selected sites in areas influenced by daily water fluctuations; (3) native species cover and richness were greater than nonnative species cover and richness across all hydrologic zones; and (4) the temporal trend metrics used here can be used across floristic groups, enabling assessment of the Colorado River ecosystem as a whole. In addition to these findings, lists of recorded plant species are included as appendixes. The variations and patterns in vegetation status and trends presented in this report can be used as a baseline against which future monitoring can be compared.
The Water Resources Division of the U.S. Geological Survey, in cooperation with State, Federal, and other local governmental agencies, obtains a large amount of data pertaining to the water resources of Maine each year. These data, accumulated during the many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. Water-resources data for the 2001 water year for Maine consists of records of stage, discharge, ground water levels, water quality of streams and ground-water wells, precipitation quantity, and snow quantity,. This report contains discharge records for: 5 gage-height stations, 58 discharge gaging stations, stream water-quality data for 3 stations, water levels for 17 ground-water wells, water-quality data for 1 ground-water well, precipitation quantity data for 12 stations, and snow quantity data for 82 stations. Additional water data were collected at other sites, not part of the systematic data-collection program, and are published as special study and miscellaneous record sections.
The Water Resources Dicipline of the U.S. Geological Survey, in cooperation with State, Federal,and other local governmental agencies, obtains a large amount of data pertaining to the water resources of Maine each year. These data, accumulated during the many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. Water-resources data for the 2004 water year for Maine consists of records of stage, discharge, ground water levels, water quality of streams and ground-water wells, precipitation quantity, and snow quantity. This report contains discharge records for: 6 gage-height stations, 62 discharge gaging stations, stream water-quality data for 6 stations, water level for 23 ground-water wells, water-quality data for 24 ground-water wells, precipitation quantity data for 15 stations, and snow quantity data for 80 stations, Additional water data were collected at other sites, not part of the systematic data-collection program, and are published as special study and miscellaneous record sections.
Review of: A Review and Synthesis of Effects of Alterations to the Water Temperature Regime on Freshwater Life Stages of Salmonids, with Special Reference to Chinook Salmon. By Dale A. McCullough. Columbia River Inter-Tribal Fish Commission. 22 February 1999. REPORT #: EPA 910-R-99-010.
Water resources data for the 2004 water year for Pennsylvania consist of records of discharge and water quality of streams; contents and elevations of lakes and reservoirs; and water levels and water quality of ground-water wells. This report, Volume 1 contains (1) discharge records for 79 continuous-record streamflow-gaging stations, 8 partial record stations, 19 special-study and miscellaneous streamflow sites; (2) elevation and contents records for 13 lakes and reservoirs, and water-quality records for 6 lakes and reservoirs; (3) water-quality records for 38 gaging stations and 12 ungaged streamsites; (4) water-quality records for 82 special-study stations; (5) water-level records for 52 network observation wells; and (6) water-quality analyses of ground water from 16 ground-water wells. Site locations are shown in figures 6-18. Additional water data collected at various sites not involved in the systematic data-collection program are also presented. These data together with the data in Volumes 2 and 3, represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State, local, and Federal agencies in Pennsylvania.
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