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Articles 5671 - 5700 of 6306

Full-Text Articles in Terrestrial and Aquatic Ecology

Remote Estimation Of The Diffuse Attenuation Coefficient In A Moderately Turbid Estuary, Richard P. Stumpf, Jonathan Pennock Dec 1991

Remote Estimation Of The Diffuse Attenuation Coefficient In A Moderately Turbid Estuary, Richard P. Stumpf, Jonathan Pennock

School of Marine Science and Ocean Engineering

Abstract

Solutions of the radiative transfer equation are used to derive relationships of water reflectance to the diffuse attenuation coefficient (K) in moderately turbid water (K > 0.5 m−1). Data sets collected from the NOAA AVHRR and in situ observations from five different dates confirm the appropriateness of these relationships, in particular the logistic equation. Values of K calculated from the reflectance data agree to within 60% of the observed values, although the reflectance derived using a more comprehensive aerosol correction is sensitive to chlorophyll concentrations greater than 50 μg L−1. Agreement between in situ and remote …


Limnology Of Two New Lakes, Mount St. Helens, Wa, Valerie Jean Kelly Nov 1991

Limnology Of Two New Lakes, Mount St. Helens, Wa, Valerie Jean Kelly

Dissertations and Theses

Coldwater Lake and Castle Lake are two new lakes which were formed in the aftermath of the volcanic eruption of Mount St. Helens, WA in May, 1980. This research describes the limnology of these lakes ten years later, and includes physical, chemical, and biological parameters. The two lakes are compared and contrasted. Previous research on the eruption and its aftermath, as well as earlier studies of the lakes are described.


Flocking Behavior Of Migratory Warblers In Winter In The Virgin Islands, David N. Ewert, Robert A. Askins Nov 1991

Flocking Behavior Of Migratory Warblers In Winter In The Virgin Islands, David N. Ewert, Robert A. Askins

Biology Faculty Publications

We assessed the flocking behavior of birds on St. John and St. Thomas, U.S. Virgin Islands, with systematic surveys along trails in moist forests. Winter residents (species breeding in North America and that winter in the Virgin Islands), all of which were warblers, comprised 91% of the individuals found in 28 flocks but only 49% of solitary individuals. The average flock size was 4.0 individuals of 3.1 species, and did not differ between St. John and St. Thomas even though the average forest tract on St. John (1,000 ha) was much larger than on St. Thomas (62 ha). Northern Parula …


A Laboratory Study Of Predation On The Trinidadian Guppy, Poecilia Reticulata, By Two Natural Piscine Predators: Effects Of Predator Size, Prey Size, And Habitat Complexity, Hayden Thomas Mattingly Oct 1991

A Laboratory Study Of Predation On The Trinidadian Guppy, Poecilia Reticulata, By Two Natural Piscine Predators: Effects Of Predator Size, Prey Size, And Habitat Complexity, Hayden Thomas Mattingly

Biological Sciences Theses & Dissertations

Test populations of different-sized guppies, Poecilia reticulata, were exposed to individuals of two natural predatory species, the pike cichlid Crenicichla a/ta and the killifish Rivulus harti, under conditions of varying prey (guppy) density and habitat complexity in the laboratory. Rivulus fed most frequently on newborn and juvenile guppies < 14 mm. Crenicichla consumed more and larger guppies than did Rivulus. The mean guppy size eaten by Crenicichla was dependent on the length of the individual predator, but as a group, the 15 Crenicichla tested were non-selective with respect to guppy size and gender. The prey gender preference of Rivulus could not he determined …


Population Dynamics Of Feral House Mice And Meadow Voles On A Dredge Disposal Site, Georgia E. Kratimenos Oct 1991

Population Dynamics Of Feral House Mice And Meadow Voles On A Dredge Disposal Site, Georgia E. Kratimenos

Biological Sciences Theses & Dissertations

The population dynamics of two species was studied for one year on Craney Island in Portsmouth, Virginia. This dredge disposal site provided good habitat for the house mouse, Mus musculus, whose opportunistic behaviors can withstand the sudden changes in a dynamic environment. Although the site was not optimal habitat, a population of Microtus pennsylvanicus, the meadow vole, was sustained there. Of the seven species of small mammals captured, 65% were house mice and 28% were meadow voles. Meadow voles were more successful at establishing short periods of residency than were house mice; on average, each meadow vole was …


Community Structure Of The Macrobenthos In Back Bay, Virginia, Michael F. Lane Oct 1991

Community Structure Of The Macrobenthos In Back Bay, Virginia, Michael F. Lane

Biological Sciences Theses & Dissertations

A study of the subtidal macrobenthos in Back Bay, Virginia was conducted to examine community structure in relation to sedimentary and water quality characteristics. Samples were collected in August and November of 1987 and February and May of 1988 at ten stations.

Three site groups and three temporal groups were identified by cluster analyses of species abundance. Species composition between site groups was relatively homogeneous and eight species accounted for most of the variation between site groups. A comparison of plots of the biological and physical data in discriminant space suggested that variations in the biological data between site groups …


The Identification, Distribution, And Status Of The Threatened Dismal Swamp Shrew (Sorex Longirostris Fisheri), Thomas M. Padgett Oct 1991

The Identification, Distribution, And Status Of The Threatened Dismal Swamp Shrew (Sorex Longirostris Fisheri), Thomas M. Padgett

Biological Sciences Theses & Dissertations

Southeastern shrews (Sorex longirostris) were trapped throughout southeastern Virginia and northeastern North Carolina to determine if any morphological characters could

be identified that would aid in the identification and distribution of the threatened subspecies Sorex l._ fisheri, endemic to the Great Dismal Swamp, the more upland nominate subspecies Sorex l. longirostris, and possible intergrades between the two subspecies. Animals were classified a priori into three groups, based on their location of capture. Animals collected from the Great Dismal Swamp National Wildlife Refuge (GDSNWR) and associated bottomland habitats were designated as "fisheri", animals collected farthest from the Swamp as "longirostris", and …


Phyletic Coevolution Between Subterranean Rodents Of The Genus Ctenomys (Rodentia: Hystricognathi) And Nematodes Of The Genus Paraspidodera (Heterakoidea: Aspidoderidae) In The Neotropics: Temporal And Evolutionary Implications, Scott Lyell Gardner May 1991

Phyletic Coevolution Between Subterranean Rodents Of The Genus Ctenomys (Rodentia: Hystricognathi) And Nematodes Of The Genus Paraspidodera (Heterakoidea: Aspidoderidae) In The Neotropics: Temporal And Evolutionary Implications, Scott Lyell Gardner

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Coevolution was studied in six species of rodents of the genus Ctenomys and their parasitic nematodes of the genus Paraspidodera, collected in Bolivia. Representatives of the families Octodontidae and Caviidae were used as outgroups for the mammals, and nematodes from caviids were used as outgroups of the nematodes from ctenomyids. For the nematodes, quantitative and qualitative morphological characteristics of both males and females and electrophoretic characters of both sexes were used to generate phylogenetic hypotheses of evolutionary relationships of the OTUs occurring in hosts of different species. Concordance estimates of cladograms generated from biochemical-genetic and morphological data of the …


Landscape Plants, Forest Trees, And Crops Most Resistant To Mammal Damage: An Overview, Rex E. Marsh Apr 1991

Landscape Plants, Forest Trees, And Crops Most Resistant To Mammal Damage: An Overview, Rex E. Marsh

Great Plains Wildlife Damage Control Workshop Proceedings

To capitalize on mammal-resistant plants, several approaches may be taken. The most common is to select crops not highly prone to mammal damage (i.e., resistant crops). If a generally susceptible crop is to be grown, the more resistant varieties or cultivars of that crop can be selected, if known. An approach that has not received the attention it warrants is the selection of parent stock with resistant characteristics and the selective breeding of useful species to develop strains, hybrids, or cultivars with improved mammal resistance. For several reasons, this latter approach shows the most promise for forest tree species. It …


Protecting Forests For Wildlife, Robert A. Askins Jan 1991

Protecting Forests For Wildlife, Robert A. Askins

Biology Faculty Publications

The subject of managing forests for wildlife is being viewed from a new perspective, a perspective that has developed primarily as a result of studies of forest-interior birds. Forest-interior birds are dependent to a large extent on how forest lands are managed. They are essentially forest specialists and are not normally seen in open areas such as the suburbs, open fields or meadows. In Connecticut and other parts of the northeastern United States, most forest-interior birds are members of one taxonomic group, the wood warblers.


Synopsis Of The Notonectidae Of Arkansas, Stephen W. Chordas Iii, George L. Harp Jan 1991

Synopsis Of The Notonectidae Of Arkansas, Stephen W. Chordas Iii, George L. Harp

Journal of the Arkansas Academy of Science

No abstract provided.


Assessment Of Organic And Metal Contaminants In Lower Back Bay And Upper Currituck Sound, Kate Benkert Jan 1991

Assessment Of Organic And Metal Contaminants In Lower Back Bay And Upper Currituck Sound, Kate Benkert

V. Poster Abstracts

Studies were conducted at Mackay Island National Wildlife Refuge in 1988 and 1989 to provide baseline data for an assessment of organic chemicals and metal contaminants in the aquatic ecosystem. Longnose gar, gizzard shad, snapping turtles, common rangia clams and sediments were collected from sites in lower Back Bay and upper Currituck Sound for contaminant analyses.

Composite sediment samples were analyzed for the presence of metals, organochlorine pesticides and polycyclic aromatic hydrocarbons (PAHs). Organochlorine pesticides were not detected in the sediments. Various PAH compounds were detected in the sediments, although at trace concentrations which just exceeded the analytical detection limit …


The Distribution And Reproductive Phenology Of The Milkweeds (Asclepiadaceae: Asclepias And Cynanchum) In Nebraska, Robert B. Kaul, Steven B. Rolfsmeier, Jeffrey J. Esch Jan 1991

The Distribution And Reproductive Phenology Of The Milkweeds (Asclepiadaceae: Asclepias And Cynanchum) In Nebraska, Robert B. Kaul, Steven B. Rolfsmeier, Jeffrey J. Esch

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

The Asclepiadaceae are represented in Nebraska by seventeen native species of Asclepias and one of Cynanchum. Two species are here added to the State's flora: Asclepias asperula and A. purpurascens. Detailed county distribution maps are presented for all species based upon our extensive field and herbarium work, and numerous additions and corrections are made to the maps published in the Atlas of the Flora of the Great Plains in 1977. A map is presented showing the zone of hybridization of A. speciosa with A. syriaca in central Nebraska. Data are given on flowering and fruiting phenology for each …


New And Corrected Floristic Records For Nebraska, Steven B. Rolfsmeier, Robert B. Kaul, David M. Sutherland Jan 1991

New And Corrected Floristic Records For Nebraska, Steven B. Rolfsmeier, Robert B. Kaul, David M. Sutherland

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Nineteen species (including eight Eurasian ones) are newly recorded for Nebraska: Alopecurus arundinaceus, Amaranthus californicus, Asclepias asperula, A. purpurascens, Cardamine {lexuosa*, Centaurea diffusa, Dipsacus laciniatus, Eriochloa villosa, Euclidium syriacum, Gentiana alba, Geranium viscosissimum, Geum vernum, Goodyera oblongifolia, Haplopappus multicaulis, Heterotheca latifolia, Lathyrus tuberosus, Polygonum douglasii, Scirpus saximontanus, Veronica biloba. Twenty-one others are shown to be more widespread in Nebraska than previously known, one has a more restricted range than previously reported, two (Scirpus smithii, S. torreyi) are deleted from the flora based upon corrected identifications, and the status of some rarely-collected species is updated. Thirty-two additions, two …


Vegetation Of Greenbottom Swamp, Cabell County, West Virginia, Honggang Liu Jan 1991

Vegetation Of Greenbottom Swamp, Cabell County, West Virginia, Honggang Liu

Theses, Dissertations and Capstones

This research is a study of wetland vegetation in Greenbottom Swamp, Cabell County, West Virginia. Based on the field data and computer data processing, seven plant community types were recognized: Salix nigra-Acer saccharinum, Salix nigra-Plantanus occidentalis, Acer saccharinum-Plantanus occidentalis, Acer saccharinum-Salix nigra, Typha latifolia-Saururus cernuus, Cephalanthus occidentalis and Leersia oryzoides. Several species, Acer saccharinum, Salix nigra, Plantanus occidentalis, Cephalanthus occidentalis, Saururus cernuus, Hibiscus moscheutos, Leersia oryzoidse, Lemna minor and Spirodella polyrhiza are dominate plants in different plant community layers. Each community type occupies an area with certain environmental …


Landowner Reports Of Deer Hunter Damage In Arkansas, Richard A. Kluender, T. Bentley Wigley Jr. Jan 1991

Landowner Reports Of Deer Hunter Damage In Arkansas, Richard A. Kluender, T. Bentley Wigley Jr.

Journal of the Arkansas Academy of Science

Damage to property from deer hunters, though usually not discovered immediately, is a problem for many Arkansans. A questionnaire survey was mailed to 3,773 rural landowners in Arkansas to determine the type and cost of damage suffered from hunters. Thirty-five percent reported minor problems, and 15% reported severe damage from hunters. The most common problems caused by hunters were fence cutting (33%), severe littering (16%), road damage (13%), crop damage (10%), cattle shot (8%), gates left open (6%), and trespassing (6%). Eighty-three (5%) of the landowners reported damage costs of $500 or more; one sustained a $15,000 loss. Total state-wide …


Distribution And Habitat Of Utilization Of The Four-Toed Salamander, Hemidactylium Scutatum, In The Ouachita Mountains Of Arkansas, David A. Saugey, Stanley E. Trauth Jan 1991

Distribution And Habitat Of Utilization Of The Four-Toed Salamander, Hemidactylium Scutatum, In The Ouachita Mountains Of Arkansas, David A. Saugey, Stanley E. Trauth

Journal of the Arkansas Academy of Science

Four-toed salamanders in Arkansas represent a disjunct population separated from their main range in the eastern United States and Canada. Until recently, the distribution of this species was documented by a few individual specimens collected or observed from widely spaced localities which has resulted in its being considered rare and vulnerable. Recent investigations of distribution and habitat utilization indicate this species may be more common than previously believed, but also reaffirms the need to protect riparian habitat, springs, ponds, woodland seeps and other preferred, moist habitats containing mossy areas used as primary egg deposition sites.


Five-Year Study Of Geocarpon Minimum At Warren Prairie Natural Area Bradley County, Arkansas, William M. Shepherd, Charles R. Preston, Robert Steinauer Jan 1991

Five-Year Study Of Geocarpon Minimum At Warren Prairie Natural Area Bradley County, Arkansas, William M. Shepherd, Charles R. Preston, Robert Steinauer

Journal of the Arkansas Academy of Science

Geocarpon minimum, listed by the U.S. Fish & Wildlife Service as threatened, was monitored at Warren Prairie Natural Area, Bradley County, Arkansas, 1986-90. Selected environmental variables were compared with Geocarpon productivity plot by plot. Principal components (PC) analysis generated two eigenvectors that jointly accounted for 30% of the variation among plots. PC-l describes an exposure gradient; high-productivity plots had less litter and grass cover, more cryptogamic lip, and more iron nodules lying on the surface than most other plots. PC-II was more useful for separating highly productive plots from all other plots; the highly productive plots lay in close proximity …


Slope Effects On Shortwave Radiation Components And Net Radiation: Interim Report For Period April 1, 1991- December 31, 1991, E. A. Walter-Shea, B. L. Blad, C. J. Hays, M. A. Mesarch Jan 1991

Slope Effects On Shortwave Radiation Components And Net Radiation: Interim Report For Period April 1, 1991- December 31, 1991, E. A. Walter-Shea, B. L. Blad, C. J. Hays, M. A. Mesarch

School of Natural Resources: Documents and Reviews

No abstract provided.


Past And Present Distribution Of The Red-Cockaded Woodpecker Picoides Borealis And Its Habitat In The Ouachita Mountains, Arkansas, Joseph C. Neal, Warren G. Montague Jan 1991

Past And Present Distribution Of The Red-Cockaded Woodpecker Picoides Borealis And Its Habitat In The Ouachita Mountains, Arkansas, Joseph C. Neal, Warren G. Montague

Journal of the Arkansas Academy of Science

Within the past 15 years, at least 41 and probably more active cavity tree clusters (or colonies) of Red cockaded Woodpeckers (Picoides borealis) have existed in remnant, mature shortleaf pine (Pinus echinata) woodlands in the Ouachita Mountains of Arkansas. These clusters were located on both private timberlands and in the Ouachita National Forest. Fewer than half of this number were still active in early 1991, and none remained on private timberlands. The species is presently restricted to the xeric, western margins of the Ouachitas in Scott and Polk counties within the confines of the Ouachita National Forest where it receives …


An Analysis Of Stomach Contents Of The Ouachita Madtom In Three Streams Of The Upper Saline River Drainage, Arkansas, Tim M. Patton, Mark L. Zornes Jan 1991

An Analysis Of Stomach Contents Of The Ouachita Madtom In Three Streams Of The Upper Saline River Drainage, Arkansas, Tim M. Patton, Mark L. Zornes

Journal of the Arkansas Academy of Science

A study was conducted to identify typical foods eaten by the Ouachita madtom (Noturus lachneri), an endemic ictalurid of central Arkansas, and to compare these foods to the invertebrate community. Fish and invertebrate samples were collected in August and October, 1990, from a pool and adjacent riffle habitat in each of 3 streams in the upper Saline River drainage. Kick-net and electrofishing samples were collected at each site and the invertebrate organisms were identified to the lowest possible taxa. Stomachs from the N. lachneri specimens were removed and the contents were identified to order. Frequency of occurrence of each taxon …


Distribution, Scutellation, And Reproduction In The Queen Snake, Regina Septemvittata (Serpentes: Colubridae), From Arkansas, Stanley E. Trauth Jan 1991

Distribution, Scutellation, And Reproduction In The Queen Snake, Regina Septemvittata (Serpentes: Colubridae), From Arkansas, Stanley E. Trauth

Journal of the Arkansas Academy of Science

The queen snake, Regina septemvittata, has a disjunct portion of its distribution in Arkansas. This rare, crayfish-eating species is best known from only a few isolated populations from several major streams that flow out of the Boston Mountains of the Ozark Plateau. A field study of this species was conducted during the summer of 1990, and only 4 specimens were documented. Gravid females were collected in July; sperm production was also noted in July. Parturition presumably takes place in August or early September. This species may qualify as threatened or endangered in Arkansas.


Aggressive Interactions Between Male Cotton Mice (Peromyscus Gossypinus) And Male Texas Mice (P. Attwateri), John A. Peppers, David W. Royal, Gary A. Heidt Jan 1991

Aggressive Interactions Between Male Cotton Mice (Peromyscus Gossypinus) And Male Texas Mice (P. Attwateri), John A. Peppers, David W. Royal, Gary A. Heidt

Journal of the Arkansas Academy of Science

No abstract provided.


Introgression Of Coyote Mitochondrial Dna Into Sympatric North American Gray Wolf Populations, Niles Lehman, Andrew Eisenhawer, Kimberly Hansen, L. David Mech, Rolf O. Peterson, Peter J. P. Gogan, Robert K. Wayne Jan 1991

Introgression Of Coyote Mitochondrial Dna Into Sympatric North American Gray Wolf Populations, Niles Lehman, Andrew Eisenhawer, Kimberly Hansen, L. David Mech, Rolf O. Peterson, Peter J. P. Gogan, Robert K. Wayne

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Mitochondrial DNA (mtDNA) genotypes of gray wolves and coyotes from localities throughout North America were determined using restriction fragment length polymorphisms. Of the 13 genotypes found among the wolves, 7 are clearly of coyote origin, indicating that genetic transfer of coyote mtDNA into wolf populations has occurred through hybridization. The transfer of mtDNA appears unidirectional from coyotes into wolves because no coyotes sampled have a wolf-derived mtDNA genotype. Wolves possessing coyote-derived genotypes are confined to a contiguous geographic region in Minnesota, Ontario, and Quebec, and the frequency of coyote- type mtDNA in these wolf populations is high (> 500%). The …


Littoral And Limnetic Zooplankton Communities In Lake Mead, Nevada-Arizona, Usa, Patrick J. Sollberger, Larry J. Paulson Jan 1991

Littoral And Limnetic Zooplankton Communities In Lake Mead, Nevada-Arizona, Usa, Patrick J. Sollberger, Larry J. Paulson

Publications (WR)

Zooplankton were collected from adjacent littoral and limnetic sites in Lake Mead, Nevada-Arizona, USA. Limnetic species dominated both littoral and limnetic zooplankton communities; littoral species rarely exceeded 2% of monthly total zooplankton densities. Low species richness of littoral taxa and high similarity in species composition between littoral and limnetic habitats appeared to result from uniform horizontal physical and chemical environments, due to horizontal mixing, and from the absence aquatic macrophytes. Significant differences in spatial distribution occurred in phytoplankton biomass, total zooplankton density, and fish "abundances; highest concentrations of these factors occurred nearest an inflow high in nutrients and progressively declined …


A Report On Black-Tailed Prairie Dogs In Nebraska, Their Biology, Behavior, Ecology, Management, And Responses To A Visual Barrier Fence, Nancy S. Foster Dec 1990

A Report On Black-Tailed Prairie Dogs In Nebraska, Their Biology, Behavior, Ecology, Management, And Responses To A Visual Barrier Fence, Nancy S. Foster

School of Natural Resources: Dissertations, Theses, and Student Research

I examined the effects of a visual barrier fence, which had a see-through visibility of 600/0, on the foraging, vigilance, and aggressive behaviors of adult female black-tailed prairie dogs from June through August 1990 in central Nebraska. I also examined changes in their home ranges and use of an area in response to this fence. Prairie dogs prefer an open view of their surroundings. Therefore, I expected animals near a visual barrier to spend more time in vigilance and aggression, and less time foraging. Adult female prairie dogs exposed to the visual barrier devoted more time to foraging and less …


Lake Mead Nutrient Enhancement Project, Peter D. Vaux, Larry J. Paulson, Nevada Department Of Wildlife, National Oceanic And Atmospheric Administration Dec 1990

Lake Mead Nutrient Enhancement Project, Peter D. Vaux, Larry J. Paulson, Nevada Department Of Wildlife, National Oceanic And Atmospheric Administration

Publications (WR)

The Lake Mead Fertilization Project is a research program designed to investigate the potential for using large-scale artificial fertilization to enhance the game fisheries of this reservoir through an increase in the population of threadfin shad, the system's primary forage species. A substantial decline in the population of largemouth bass, together with poor condition of adult striped bass, are the two major issues affecting the Lake Mead game fisheries. Both issues have been hypothesized to be a result of an inadequate amount of forage in the reservoir. Previous studies have in turn suggested that a major factor limiting the shad …


Highway Deicing Salts And The Mobilization Of Selected Heavy Metals From Stream Sediments, Harlie David Cole Aug 1990

Highway Deicing Salts And The Mobilization Of Selected Heavy Metals From Stream Sediments, Harlie David Cole

Dissertations

This study was undertaken to: (a) determine the effect of sodium chloride concentration on mobilizing cadmium, copper, lead, nickel, and zinc from stream sediments; (b) determine if chloro-metal complexes may play a role in any such mobilization; and (c) determine the correlations between chloride ion and each of these metals in an urban stream during winter road-salting periods.

The drainage basin of the Red Run, an urban stream draining all or parts of several cities north of Detroit, Michigan, was chosen as a study site. Stream sediments containing the five heavy metals were stirred with sodium chloride or sodium nitrate …


Phytoplankton In Lake Drummond And Two Drainage Ditches In The Great Dismal Swamp, Virginia, Christine Gregory Phillips Jul 1990

Phytoplankton In Lake Drummond And Two Drainage Ditches In The Great Dismal Swamp, Virginia, Christine Gregory Phillips

Biological Sciences Theses & Dissertations

A twelve month study was conducted on the phytoplankton of Lake Drummond and Washington and Jericho Ditches from December 1988 to November 1989. Surface water samples were collected for nutrient and chlorophyll analysis from June 1989 to November 1989. The dominant phytoplankton component was the pico-nanoplankton (< 3 micron) category. A total of 57 species were identified from Lake Drummond, 51 species from Washington Ditch, and 31 species from the Jericho Ditch. Three major phytoplankton groups were identified at these sites: bacillariophyceans, cyanophyceans and cryptophyceans. The dominant species was the diatom Asterionella formosa. Nutrient and chlorophyll concentrations increased from summer to fall. Based on nutrient and chlorophyll g concentrations and species diversity indices, Lake Drummond is classified as eutrophic.


An Autecological Study Of Pyxidanthera Barbulata In The Blackwater Ecologic Preserve Virginia, John Marc Lowenthal Jul 1990

An Autecological Study Of Pyxidanthera Barbulata In The Blackwater Ecologic Preserve Virginia, John Marc Lowenthal

Biological Sciences Theses & Dissertations

Pyxidanthera barbulata (pyxie moss), a rare and endangered subshrub, has been found in decreasing numbers in it's "pine barren" habitat. An autecological study encompassing vegetation association analysis and environmental measurements was performed in the Blackwater Ecologic Preserve, its only known location in Virginia. The preserve is being subjected to controlled burning and the effect of burning on the species was evaluated. A multivariate analysis of variance was performed to identify species associations, and simple analysis of variance was done to find trends in the environmental data. Four taxa were positively associated with P. barbulata, Gaultheria procumbens, Vaccinium tenellum, Cladonia spp., …