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1.
Blue Lake Warm Spring in Tooele County, Utah, contains a rich diatom flora with a significant number of taxa that are unusual in this region. We have identified a total of 136 taxa in our samples from this locality, several of which are new records for Utah and North America. 相似文献
2.
The sagebrush biotype is the largest in the western United States. This vast sagebrush community is thought to harbor equally vast and diverse arthropod communities, but these remain little explored. Our objective was to examine the diversity, abundance, and seasonal phenology of arthropod taxa found on the dominant shrub of the sagebrush ecosystem, big sagebrush ( Artemisia tridentata ). We wanted to improve understanding of this little-studied arthropod assemblage that may play significant roles in the dynamics of sagebrush populations and the sagebrush ecosystem. We sampled free-living and gall-forming arthropods from a stratified random sample of sagebrush plants at the Barton Road Ecological Research Area, Idaho, resulting in a sample of over 8000 individuals and 232 morphospecies. Species richness and abundance declined from May to August, and abundance of most taxa similarly declined over the summer. A few taxa, including Acari (mites), were notably more abundant in August. Fluid feeders were the most diverse and abundant free-living feeding guild during all months and comprised up to 79% of morphospecies. The gall formers included 4713 individuals of 12 species of gall flies ( Rhopalomyia spp.), primarily (97%) R. ampullaria. Abundance of galls increased from small to large (presumably young to old) plants. Overall, A. tridentata was host to a high diversity of arthropods, some of which have potential to cause or mitigate significant damage to their host plant. Arthropods seem likely to have the greatest impact on sagebrush early in the growing season, when they are most diverse and abundant. Documentation of the full diversity of arthropods associated with sagebrush required samples taken throughout the growing season, but a single sample early in the growing season captured a high proportion of taxa. 相似文献
3.
Jack D. Brotherson 《西北部美国博物学家》2011,47(2)
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Patterns of zonation along a saline meadow slope were studied. Different species associations were distributed in five zones along the slope which paralleled Utah Lake. The five zones, distinguished on the basis of dominant species and/or life form, were: saltgrass–annual weed, saltgrass-alkaligrass, saltgrass-forb, saltgrass, and spikerush. Soil, vegetation, and plant species data were taken. Patterns of change with respect to these factors were observed along the downslope gradient. Soil pH and soluble salts decreased downslope, while organic matter and moisture increased. Individual ions showed varying patterns. Vegetation and species patterns also varied with slope position. Annuals dominated the ridge tops, while sedge and rush cover were restricted to the slope base. Perennial forb distribution was shown to be correlated with elevated levels of micronutrients in the soil. 相似文献
4.
Peter J. Perkins Frederick G. Lindzey Jay A. Roberson Gregory McDaniel Randy Berger 《西北部美国博物学家》2011,49(2)
Winter habitat use and food habits of Blue Grouse ( Dendragapus obscurus ) were studied in an isolated Utah desert mountain range that contained little typical Douglas-fir ( Pseudotsuga menziesii ) winter habitat. Habitat use was concentrated in the Douglas-fir and pinyon ( Pinus edulis )-juniper ( Juniperus spp. ) habitat. Douglas-fir and pinyon pine were the most consumed foods. Other foods that represented >15% of the composition of an individual fecal sample were limber pine ( Pinus flexilis ), mahogany ( Cercocarpus ledifoliu ), juniper, and an Anteunaria-Cirsium type. The breadth in winter diet indicates that Blue Grouse may successfully occupy other habitats when typical winter habitat is scarce. 相似文献
5.
A questionnaire survey was conducted in Sanpete County, Utah, to determine the knowledge of dog owners concerning hydatid disease and an identification of some basic sheep management practices there. The households surveyed included 21 (Group I) that had one or more dogs infected with Echinococcus granulosus tapeworms at more than one annual field clinic, and 19 others (Group II) that had one or more dogs infected when the study first began in 1971–72, but had not had any infected dogs identified at field clinics during subsequent years. The results showed that 92.5 percent of households knew the cause of the disease and how it is transmitted, and that 90 percent knew of someone who had been operated on for surgical removal of hydatid cysts. There was no significant difference in the level of knowledge of the disease between the two groups of respondents, nor in their sheep management practices. Even though the level of infection of the parasite in dogs has decreased since the project started, certain sheep management practices persist among respondents in both groups that allow for continued transmission of the parasite in this region. 相似文献
6.
David L. Sturges 《西北部美国博物学家》2011,40(2)
Seasonal depletion by vegetation where sagebrush was selectively removed by grubbing and where sagebrush was sprayed with 2,4-D was 33 and 12 percent less, respectively, than that for undisturbed big sagebrush vegetation in the surface 122 cm of soil. Differences were located primarily below 61 cm in vegetation grubbed the previous fall and below 91 cm in vegetation sprayed three years previously. Total root weights under grubbed and sprayed vegetation were 29 and 16 percent less, respectively, than for undisturbed big sagebrush vegetation. Total herbaceous production by grubbed and sprayed vegetation was 69 and 43 percent less, respectively, than production by undisturbed vegetation. 相似文献
7.
A survey of parasites from 39 stool specimens taken from 36 Indochinese refugees who are now living in Utah County, Utah, indicated representative intestinal helminths (worms), and protozoans upon clinical examination. .Approximately 75% of the stools contained nematodes, and 55.5% had protozoans. Parasites found were Entamoeba coli, Chilomastix mesnili, Endolimax nana, Giardia lamblia, lodamoeba buetschlii, Clonorchis sinensis, Trichuris trichiura, Ascaris lumbricoides, and Plasinodium vivax. The most common protozoan observed was Entamoeba coli (1979 and 1980) while the most common helminths were Ascaris lumbricoides ) (1979) and Clonorchis sinensis (1980). These data were comparable to studies of refugees at two other laboratories in Utah and one at Washington, D.C. 相似文献
8.
The plant communities and individual plant species in and around a salt playa near Goshen, Utah County, Utah, were studied in relation to gradients for soluble salts, soil moisture, and pH. Forty-eight stands were sampled. Frequency data were taken for all plant species. Soil samples were collected from each site and analyzed to establish the environmental gradients. Results indicate that the vegetational types respond differentially to the three gradients and can be segregated on the basis of one or more of the gradients. The total soluble salts gradient was found to be the most influential of the three sampled. Correlation analysis indicates that 45 percent of the variation in plant diversity can be accounted for by the three gradients. Distributional patterns of individual plant species are strongly influenced by the three gradients. Niche width measurements exhibited no correlation with the measured gradients. 相似文献
9.
Bottle Hollow Reservoir contains a diverse algal flora. A total of 289 taxa was observed, 227 of which were diatoms. Both littoral and planktonic communities had high diatom diversity. During summer months filamentous Chlorophvta were diverse and high in biomass in the littoral zone. Phytoplankton collections in Bottle Hollow Reservoir were dominated by four species: Asterionella formosa, Cyclotella comta, Dinobryon divergens, and Fragilaria crotonensis. Plankton samples contained mostly small diatoms in early spring, with larger algae succeeding these as the summer progressed. No blue - green algae were important in this succession. Two peak production periods were observed, one in the fall and one in the spring. Bottle Hollow Reservoir appears to be a healthy mesotrophic system based on the evidences of moderately high algal diversity, insignificance of blue-green algae, and the presence of a suite of diatom species indicative of mesotrophic conditions. 相似文献
10.
Aaron L. Holmes 《西北部美国博物学家》2011,67(2)
I measured songbird abundance and vegetation cover in and around a 420-ha prescribed burn in a mountain big sagebrush community located at 2133 m elevation. Data were collected during the 3rd growing season after the fire. Brewer's Sparrow and Sage Thrasher occurred in lower abundance on sites that were largely or completely burned relative to sites that were outside the fire perimeter or within unburned islands of shrubs. The number of Brewer's Sparrow detections was linearly related to remaining sagebrush cover. In contrast, Horned Lark occurred at higher abundances on sites where shrub cover had been removed in the prescribed burn. Cover of perennial grasses and cover of 4 of the 5 most common forbs was greater on burned sites than on unburned sites. 相似文献
11.
Mountain big sagebrush ( Artemisia tridentata Nutt. ssp. vaseyana ) covers large areas in arid regions of western North America. Climate-change models predict a decrease in the range of sagebrush, but few studies have examined details of predicted changes on sagebrush growth and the potential impacts of these changes on the community. We analyzed effects of temperature, precipitation, and snow depth on sagebrush annual ring width for 1969 to 2007 in the Gunnison Basin of Colorado. Temperature at all times of year except winter had negative correlations with ring widths; summer temperature had the strongest negative relationship. Ring widths correlated positively with precipitation in various seasons except summer; winter precipitation had the strongest relationship with growth. Maximum snow depth also correlated positively and strongly with ring width. Multiple regressions showed that summer temperature and either winter precipitation or maximum snow depth, which recharges deeper soil horizons, are both important in controlling growth. Overall, water stress and perhaps especially maximum snow depth appear to limit growth of this species. With predicted increases in temperature and probable reduced snow depth, sagebrush growth rates are likely to decrease. If so, sagebrush populations and cover may decline, which may have substantial effects on community composition and carbon balance. 相似文献
12.
Abundance, seasonal use, and species composition of waterfowl and other aquatic birds are described along a 32.8 km stretch of the White River, Uintah County, Utah, at the site of the proposed White River Dam. Fourteen species of waterfowl and eight other species of aquatic birds were recorded. Waterfowl populations along the river were highest in April, but densities were much lower than on lakes and reservoirs at nearby Ouray National Wildlife Refuge. 相似文献
13.
A. Gaylon Cook 《西北部美国博物学家》2011,44(4)
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} The Common Loon, White Pelican, Double-crested Cormorant, recurvirostrids, and most grebes, waterfowl, gulls, and terns have become more abundant in Uintah County, Utah, since 1937 (Twomey 1942) due to the establishment of Pelican Lake and adjacent water bodies and the ponds and marshes at Ouray National Wildlife Refuge and Pariette Wetlands Wildlife Management Area. The incidence of herons, egrets, thrushes, nuthatches, and icterids has generally remained about the same since 1937. Diurnal raptors have largely declined in abundance in the desert region of Uintah County since Twomey’s (1942) study. Plovers, sandpipers, phalaropes, and the White-faced Ibis were generally less common in 1977–1982 than in 1937, perhaps chiefly due to their displacement from wintering grounds by human population expansion and agricultural and industrial development. The incidence of owl species remains constant. Most flycatchers, swallows, warblers, vireos, orioles, and emberizids have diminished in number since 1937, probably because of the shrinkage of their winter habitats in Latin America and the southwestern U.S. The Blue Grosbeak and Black-throated Sparrow were not recorded in Uintah County in 1937 but were found there during this study and may represent a range extension northward since 1937. The Blue-gray Gnatcatcher is more common now than in 1937 due to the northward extension of its range. The Starling and Rock Dove and, more recently, the Common Grackle, Great-tailed Grackle, and Cattle Egret have invaded Uintah County due to the expansion of their ranges. It is not clear why the Pine Siskin, House Finch, and most corvids are presently less common than in 1937. 相似文献
14.
Harold J. Egoscue 《西北部美国博物学家》2011,37(1)
The sagebrush vole flea ( Megabothris clantoni princei Hubbard) is reported from Utah for the first time, based on collections made in Tooele County. Distribution of the flea Megabothris abantis in the Bonneville Basin is limited to the Oquirrh Mountains, where its presence appears to be determined by the occurrence of the western jumping mouse. 相似文献
15.
The diatom flora of Beaver Dam Creek, Washington County, Utah, was studied. The study area is in a warm Mojave Desert environment at an elevation between 810 and 850 m. A total of 99 taxa were identified from composite samples taken in the fall, winter, spring, and summer seasons. These taxa are all broadly distributed and no endemic species were encountered. Three new records for the state of Utah were identified: Gomphoneis eriense Skv. & Mayer, Navicula elginensis var. lata. (M. Perag.) Patr., and Nitzschia calida Grun. The most important taxa throughout the study as determined by multiplying percent presence by average relative density (Important Species Index) were Cymbella affinis Kütz., Epithemia sorex Kütz., Navicula veneta Kütz., Nitzschia palea (Kütz.) W. Sm., and Nitzschia microcephala Grun. 相似文献
16.
Dan Blumgart Julia Dolhem Christopher J. Raxworthy 《Journal of Natural History》2017,51(11-12):625-642
A six month herpetological survey was undertaken between March and September 2015 on Nosy Komba, an island off of the north-west coast of mainland Madagascar which has undergone considerable anthropogenic modification. A total of 14 species were found that have not been previously recorded on Nosy Komba, bringing the total island diversity to 52 (41 reptiles and 11 frogs). The species assemblage, richness and abundance of four distinct habitat types were compared: closed-canopy forest, disturbed-canopy forest, shade-grown coffee plantation and mixed open plantation. The anthropogenic habitats on Nosy Komba were found to be of high conservation value for reptile species, where species richness and abundance found during surveys was equal to or higher than closed-canopy forest. By contrast, the abundance and species richness for frogs was reduced in anthropogenic habitats, especially in sun-exposed plantations. The forested areas of Nosy Komba contain twelve IUCN threatened species (9 reptiles and 3 frogs). Of these, Uroplatus henkeli, Uroplatus ebenaui, Phelsuma seippi, Zonosaurus subuniclor, Stumpffia psologlossa and Stumpffia pygmaea were also found in shade-grown coffee plantations, demonstrating the conservation value of these anthropogenic environments. Five threatened species on Nosy Komba were found exclusively in forested areas: Brookesia minima, Brookesia ebenaui, Lygodactylus madagascariensis, Rhombophryne testudo and Thamnosophis stumpffi. Our surveys demonstrate the importance of Nosy Komba for conserving regionally endemic and threatened species, and the often under-appreciated value of anthropogenic environments in species conservation, when also coupled with the protection of primary forest. 相似文献
17.
Patterns of change in the woody vegetation (trees and shrubs) of the riparian communities of three streams draining the slopes of the Pine Valley Mountains in Washington County, Utah, were examined. Thirty-nine study sites were established adjacent to the streams along an elevational gradient where vegetation, plant population, and species data were taken. Vegetation and species patterns varied with respect to elevation and geographical location. Vegetation of the high- and low-elevation areas was distinctly different, while that of the mid-elevations was transitional to both. Geographical patterns showed a north-south transition in vegetation between the Mojave and Great Basin deserts. Size-class distribution curves for 11 tree species showed varying degrees of survival with respect to age and location. Root sprouting was highly important in the reproductive effort of six of the trees. Species distribution patterns followed transriparian and intrariparian gradients within the riparian community. 相似文献
18.
Diatoms from core samples obtained from the edge of Lily Lake, Summit County, Utah, were studied. Populations from each 15 cm of the core and niche metrics of the important species were analyzed. This study demonstrates four periods of history in the lake as mirrored by the diatom populations. The first period was mesotrophic and alkaline. This graded into an acidic, dystrophic period which in turn yielded again to a mesotrophic alkaline period. The most recent period can be characterized by a return to dystrophy. 相似文献
19.
Sara C. Gillespie Dirk H. Van Vuren Douglas A. Kelt John M. Eadie Daniel W. Anderson 《西北部美国博物学家》2011,68(1)
From 1996 to 2004, we studied population dynamics of a rodent assemblage in semiarid habitats in Lassen County, California. Abundances of rodents appeared affected by fluctuations in precipitation from a high in 1996 to average and slightly below-average levels in subsequent years; perhaps reflecting this, assemblage composition also changed dramatically during the study period. California kangaroo rats ( Dipodomys californicus ) declined from abundant to extremely rare, abundances of deer mice ( Peromyscus maniculatus ) fluctuated greatly during the study period, and, perhaps most notably, populations of dusky-footed woodrats ( Neotoma fuscipes ) appeared to decline to local extinction, possibly allowing for the subsequent colonization of desert woodrats ( N. lepida ). These changes appeared to represent natural variation in numbers and composition in an ecologically dynamic ecotonal region in response to multiyear changes in precipitation. 相似文献
20.
James V. Robinson 《西北部美国博物学家》2011,44(1)
Of the eight most frequently collected spiders at a northern Utah study site, each of two species employed one of the following hunting strategies: pursuing, web building, jumping, and ambushing. Within each pair, size differences between species were substantial for all but the ambushers. The ambushers had different seasonal activity patterns, as did the web builders. 相似文献