Molecular aggregation of humic substances
Robert L. Wershaw
1999, Soil Science (164) 803-813
Humic substances (HS) form molecular aggregates in solution and on mineral surfaces. Elucidation of the mechanism of formation of these aggregates is important for an understanding of the interactions of HS in soils arid natural waters. The HS are formed mainly by enzymatic depolymerization and oxidation of plant biopolymers. These...
Calcite fracture fillings as indicators of paleohydrology at Laxemar at the Aspo Hard Rock Laboratory, southern Sweden
B. Wallin, Z. Peterman
1999, Applied Geochemistry (14) 953-962
Isotopic compositions of C (??13C), O (??18O) and Sr (??87Sr) were determined for calcite fracture fillings in the crystalline rock penetrated by a 1.6 km drill hole at Laxemar, near the Aspo Hard Rock Laboratory (AHRL) in southern Sweden. These calcites precipitated from groundwater some time in the past, and...
Technical note: A device for obtaining time-integrated samples of ruminal fluid
R. N. Corley III, M.R. Murphy, J. Lucena, S.V. Panno
1999, Journal of Animal Science (77) 2540-2544
A device was adapted to allow for time-integrated sampling of fluid from the rumen via a cannula. The sampler consisted of a cup-shaped ceramic filter positioned in the ventral rumen of a cannulated cow and attached to a tube through which fluid entering the filter was removed continuously using a...
Cu(II) binding by a pH-fractionated fulvic acid
G.K. Brown, S.E. Cabaniss, P. MacCarthy, J.A. Leenheer
1999, Analytica Chimica Acta (402) 183-193
The relationship between acidity, Cu(II) binding and sorption to XAD resin was examined using Suwannee River fulvic acid (SRFA). The work was based on the hypothesis that fractions of SRFA eluted from an XAD column at various pH's from 1.0 to 12.0 would show systematic variations in acidity and possibly...
Uncommon breeding birds in North Dakota: Population estimates and frequencies of occurrence
L.D. Igl, Douglas H. Johnson, H.A. Kantrud
1999, Canadian Field-Naturalist (113) 646-651
Breeding bird populations were surveyed on 128 randomly selected quarter-sections throughout North Dakota in 1967, 1992, and 1993. Population estimates and frequencies of occurrence are reported for 92 uncommon breeding bird species with statewide frequencies of less than 10%....
Preliminary study on the mode of occurrence of arsenic in high arsenic coals from southwest Guizhou Province
Z. Ding, B. Zheng, Jiahua Zhang, H. E. Belkin, R. B. Finkelman, F. Zhao, D. Zhou, Y. Zhou, C. Chen
1999, Science in China, Series D: Earth Sciences (42) 655-661
Coal samples from high arsenic coal areas have been analyzed by electron micropbe analyzer (EMPA), scanning electron microscopy with an energy dispersive X-ray analyzer (SEM-EDX), X-ray diffinction analysis (XRD), low temperature ashing (LTA), transmission electron microscopy (TEM), X-ray absorption fine structure (XAFS), instnunent neutron activation analysis (INAA) and wet chemical...
Habitat associations of migrating and overwintering grassland birds in southern Texas
L.D. Igl, B.M. Ballard
1999, Condor (101) 771-782
We report on the habitat associations of 21 species of grassland birds overwintering in or migrating through southern Texas, during 1991-1992 and 1992-1993. Ninety percent of our grassland bird observations were made during winter and spring, and only 10% occurred during fall. Grassland species made up a high proportion of...
Robowell: An automated process for monitoring ground water quality using established sampling protocols
G.E. Granato, K.P. Smith
1999, Ground Water Monitoring and Remediation (19) 81-89
Robowell is an automated process for monitoring selected ground water quality properties and constituents by pumping a well or multilevel sampler. Robowell was developed and tested to provide a cost-effective monitoring system that meets protocols expected for manual sampling. The process uses commercially available electronics, instrumentation, and hardware, so it...
Response of bighorn sheep to clear-cut logging and prescribed burning
T. S. Smith, P.J. Hardin, J.T. Flinders
1999, Wildlife Society Bulletin (27) 840-845
Prescribed burning and timber harvesting have been used to restore and maintain Rocky Mountain bighorn sheep (avis canadensis) ranges. Intensive study of a bighorn sheep herd in northeastern Utah indicated a need for range improvements. To evaluate the effectiveness of clear-cut logging and prescribed burning, we documented sheep responses to...
Interactive effects of nutrient additions and predation on infaunal communities
M.H. Posey, T.D. Alphin, L. Cahoon, D. Lindquist, M.E. Becker
1999, Estuaries (22) 785-792
Nutrient additions represent an important anthropogenic stress on coastal ecosystems. At moderate levels, increased nutrients may lead to increased primary production and, possibly, to increased biomass of consumers although complex trophic interactions may modify or mask these effects. We examined the influence of nutrient additions and interactive effects of trophic...
Benthic marine debris, with an emphasis on fishery-related items, surrounding Kodiak Island, Alaska, 1994-1996
N.A. Hess, C. A. Ribic, I. Vining
1999, Marine Pollution Bulletin (38) 885-890
Composition and abundance of benthic marine debris were investigated during three bottom trawl surveys in inlet and offshore locations surrounding Kodiak Island, Alaska, 1994-1996. Debris items were primarily plastic and metal regardless of trawl location. Plastic bait jars, fishing line, and crab pots were the most common fishery-related debris items...
Targeted stock identification using multilocus genotype 'familyprinting'
B. H. Letcher, T.L. King
1999, Conference Paper, Fisheries Research
We present an approach to stock identification of small, targeted populations that uses multilocus microsatellite genotypes of individual mating adults to uniquely identify first- and second-generation offspring in a mixture. We call the approach 'familyprinting'; unlike DNA fingerprinting where tissue samples of individuals are matched, offspring from various families are...
Seasonal variability in hydrologic-system response to intense rain events, Matanuska Glacier, Alaska, U.S.A.
J.C. Denner, D. E. Lawson, G.J. Larson, E.B. Evenson, R. B. Alley, J.C. Strasser, S. Kopczynski
1999, Annals of Glaciology (28) 267-271
Two rain events at Matanuska Glacier illustrate how subglacial drainage system development and snowpack conditions affect hydrologic response at the terminus. On 21 and 22 September 1995, over 56 mm of rain fell in the basin during a period usually characterized by much drier conditions. This event caused an 8-fold...
Interspecific competition in tributaries: Prospectus for restoring Atlantic salmon in Lake Ontario
James H. Johnson, Leslie R. Wedge
1999, Great Lakes Research Review (4) 11-17
Historically, Lake Ontario may have supported the world's largest freshwater population of Atlantic salmon (Salmo salar). However, by the late 1800's, salmon were virtually extinct in the lake due to the damming of tributaries, overharvest, deforestation, and pollution. Of these factors, the building of dams on tributaries, which...
Refinement, validation, and application of a benthic condition index for northern Gulf of Mexico estuaries
V.D. Engle, J.K. Summers
1999, Estuaries (22) 624-635
By applying discriminant analysis to benthic macroinvertebrate data, we have developed an indicator of benthic condition for northern Gulf of Mexico estuaries. The data used were collected by the United states Environmental Protection Agency’s Environmental Monitoring and Assessment Program (EMAP) in the Louisianian Province from 1991 to 1994. This benthic...
Structure and function of fish communities in the southern Lake Michigan basin with emphasis on restoration of native fish communities
Thomas P. Simon, Paul M. Stewart
1999, Natural Areas Journal (19) 142-154
The southern Lake Michigan basin in northwest Indiana possesses a variety of aquatic habitats including riverine, palustrine, and lacustrine systems. The watershed draining this area is a remnant of glacial Lake Chicago and supports fish communities that are typically low in species richness. Composition of the presettlement Lake Michigan fish...
Integrated foraminiferal biostratigraphy and chemostratigraphy of the querecual formation (Cretaceous), Eastern Venezuela
S. Crespo De Cabrera, W.V. Sliter, I. Jarvis
1999, Journal of Foraminiferal Research (29) 487-499
An integrated foraminiferal biostratigraphy and chemostratigraphy is presented for the Lower to Upper Cretaceous Querecual Formation exposed on Chimana Grande Island, Eastern Venezuela. The formation consists of >450 m alternating foraminiferal and organic-rich carbonates and laminated mudrocks, and is considered the main hydrocarbon source rock for the eastern Venezuela Basin....
Bacterial respiration of arsenic and selenium
J.F. Stolz, R.S. Oremland
1999, FEMS Microbiology Reviews (23) 615-627
Oxyanions of arsenic and selenium can be used in microbial anaerobic respiration as terminal electron acceptors. The detection of arsenate and selenate respiring bacteria in numerous pristine and contaminated environments and their rapid appearance in enrichment culture suggest that they are widespread and metabolically active in nature. Although the bacterial...
Community reorganization in the Gulf of Alaska following ocean climate regime shift
P.J. Anderson, John F. Piatt
1999, Marine Ecology Progress Series (189) 117-123
A shift in ocean climate during the late 1970s triggered a reorganization of community structure in the Gulf of Alaska ecosystem, as evidenced in changing catch composition on long-term (1953 to 1997) small-mesh trawl surveys. Forage species such as pandalid shrimp and capelin declined because of recruitment failure and predation,...
Estimation of nitrate contamination of an agro-ecosystem outwash aquifer using a nitrogen mass-balance budget
L.J. Puckett, T.K. Cowdery, D. L. Lorenz, J.D. Stoner
1999, Journal of Environmental Quality (28) 2015-2025
A mass-balance budget of N cycling was developed for an intensive agricultural area in west-central Minnesota to better understand NO3/- contamination of ground water in the Otter Tail outwash aquifer. Fertilizer, biological fixation, atmospheric deposition, and animal feed were the N sources, and crop harvests, animal product exports, volatilization from...
Flow-path textures and mineralogy in tuffs of the unsaturated zone
Schon Levy, Steve Chipera, Giday WoldeGabriel, June Fabryka-Martin, Jeffrey Roach, Donald S. Sweetkind
William C. Haneberg, Peter S. Mozley, J. Casey Moore, Laurel B. Goodwin, editor(s)
1999, Book chapter, Faults and subsurface fluid flow in the shallow crust
The high concentration of chlorine-36 (36Cl) produced by above-ground nuclear tests (bomb-pulse) provides a fortuitous tracer for infiltration during the last 50 years, and is used to detect fast flow in the unsaturated zone at Yucca Mountain, Nevada, a thick deposit of welded and nonwelded tuffs. Evidence of fast flow...
Stress transfer by the 1988-1989 M=5.3 and 5.4 Lake Elsman foreshocks to the Loma Prieta fault: Unclamping at the site of peak mainshock slip
H. Perfettini, R.S. Stein, R. Simpson, M. Cocco
1999, Journal of Geophysical Research B: Solid Earth (104) 20169-20182
We study the stress transferred by the June 27, 1988, M = 5.3 and August 8, 1989, M = 5.4 Lake Elsman earthquakes, the largest events to strike within 15 km of the future Loma Prieta rupture zone during 74 years before the 1989 M = 6.9 Loma Prieta earthquake. We find that the first Lake...
Regional hydrology of the Dixie Valley geothermal field, Nevada: preliminary interpretations of chemical and isotopic data
Gregory Nimz, Cathy Janik, Fraser Goff, Charles Dunlap, Mark Huebner, Dale Counce, Stuart D. Johnson
1999, Book chapter, Global geothermal resources: sustainable energy for the future
Chemical and isotopic analyses of Dixie Valley regional waters indicated several distinct groups ranging in recharge age from Pleistocene (1000a). Geothermal field fluids (~12-14 ka) appear derived from water similar in composition to non thermal groundwater observed today in valley artesian well (also ~14 ka). Geothermal fluid interaction with mafic...
Laboratory evaluation of a lake trout bioenergetics model
Charles P. Madenjian, Daniel V. O’Connor
1999, Transactions of the American Fisheries Society (128) 802-814
Lake trout Salvelinus namaycush, aged 3 and 6 years and with average weights of 700 and 2,000 g, were grown in laboratory tanks for up to 407 d under a thermal regime similar to that experienced by lake trout in nearshore Lake Michigan. Lake trout were fed alewifeAlosa pseudoharengus and rainbow smelt Osmerus...
Temporal and geographic variation in fish communities of lower Cook Inlet, Alaska
Martin D. Robards, John F. Piatt, Arthur B. Kettle, Alisa A. Abookire
1999, Fishery Bulletin (97) 962-977
Nearshore and shelf fish communities were studied in three areas of lower Cook Inlet, Alaska: the Barren Islands (oceanic and well-mixed waters), Kachemak Bay (mixed oceanic waters with significant freshwater runoff), and Chisik Island (estuarine waters). Fish were sampled with beach seines (n=413 sets) and midwater trawls (n=39 sets). We...
