Plant Community Changes Over 54 Years Within the Great Basin Experimental Range, Manti-La Sal National Forest

Plant community changes and natural succession over time impact forage values, watershed quality, wildlife habitat, and ecosystem dynamics. Comparisons were made between a vegetation map of community types completed in 1937 by the U.S. Forest Service, and vegetation maps compiled in 1990 of the same areas by satellite imagery, and through 1991 areal photo interpretation combined with ground truthing. The study area includes nearly all of the drainage in Ephraim Canyon located in central Utah which consists of 6,027 acres (2,439 ha). Elevation ranges from 6,600 to 10,400 feet (2,040 to 3,210 m). Vegetation types ranged from pinyon-juniper woodland through oakbrush, mountain shrub, aspen, conifer and subalpine herbland. The comparison showed significant plant community changes and successional trends over the 54 year period

Vegetation Dynamics at a Mojave Desert Restoration Site, 1992 to 2007

The Twist Hollow restoration site on BLM land near St. George, Utah, had been badly disturbed by sand mining, rock quarrying, dumping, off-road vehicles and target shooting prior to its closure and treatment. In December 1992 the site was sculpted and drill seeded with Indian ricegrass (Stipa hymenoides), sand dropseed (Sporobolus cryptandrus), galleta (Hilaria jamesii), gooseberryleaf globemallow (Sphaeralcea grossulariifolia) Palmer penstemon (Penstemon palmeri), fourwing saltbush (Atriplex canescens) and winterfat (Krascheninnikovia lanata) in an effort restore natural vegetation and desert tortoise habitat. Vegetation was sampled before and after treatment and subsequently monitored over a period of 14 years. With the exception of winterfat, all the seeded species established and increased in density and/or cover during the period 1993-1998. Cheatgrass (Bromus tectorum) also increased and became dominant during this period. Seeding was most successful on a rockier substrate where fourwing saltbush became a dominant shrub. Drought conditions after 1998 corresponded with declines in most seeded species while broom snakeweed (Gutierrezia sarothrae), hairy goldenaster (Chrysopsis villosa), desert globemallow (Sphaeralcea ambigua) and sandsage (Artemisia filifolia) increased through recruitment from surrounding vegetation. Sandsage was the dominant shrub of nearby undisturbed sandy sites and grew rapidly following establishment in a sandier portion of the treated area. Cheatgrass and other annuals fluctuated from year to year in the treated area but had lower density and cover than nearby untreated areas throughout the monitoring period. We conclude that the restoration project’s objectives have been met to varying degrees despite the limited persistence of the seeded species. Further research into management techniques aimed at reducing annual grasses and enhancing high-quality desert tortoise forage is recommended

Taxonomic and nomenclatural rearrangements in Artemisia subgen. Tridentatae, including a redefinition of Sphaeromeria (Asteraceae, Anthemideae)

[EN]A recent molecular phylogenetic study of all members of Artemisia subgenus Tridentatae, as well as most of the other New World endemic Artemisia and the allied genera Sphaeromeria and Picrothamnus, raised the necessity of revising the taxonomic framework of the North American endemic Artemisia. Composition of the subgenus Tridentatae is enlarged to accommodate other North American endemics and is organized into 3 sections: Tridentatae, Nebulosae, and Filifoliae. This paper deals with the combination of one section, the amendment of 2 more sections, and the combination in or the reversion to Artemisia of some Sphaeromeria and Picrothamnus species. The new names given for previous Sphaeromeria species are Artemisia macarthurii (for S. argentea), A. albicans (for S. cana), A. constricta (for S. compacta), and A. inaequifolia (for S. diversifolia). The other Sphaeromeria we studied (S. capitata, S. potentilloides, S. ruthiae, and S. simplex) had been formerly considered Artemisia (respectively, A. capitata, A. potentilloides, A. ruthiae, and A. simplex), and their previous nomenclature is therefore recommended[ES]Un estudio reciente sobre la filogenia molecular de todos los miembros del subgénero Tridentatae de Artemisia, así como de la mayoría de las otras especies de Artemisia endémicas del Nuevo Mundo y los géneros afines Sphaeromeria y Picrothamnus, hizo ver la necesidad de revisar el marco taxonómico de las especies de Artemisia endémicas a Norteamérica. La composición del subgénero Tridentatae se ha ampliado para dar cabida a las otras especies endémicas de Norteamérica, y está organizado en 3 secciones: Tridentatae, Nebulosae y Filifoliae. El presente artículo trata sobre la combinación de una sección y la enmienda de 2 más, y propone la incorporación o reversión a Artemisia de algunas especies de Sphaeromeria y Picrothamnus. Los nuevos nombres de las especies previamente asignadas a Sphaeromeria son Artemisia macarthurii (para S. argentea), A. albicans (para S. cana), A. constricta (para S. compacta) y A. inaequifolia (para S. diversifolia). Las otras especies de Sphaeromeria estudiadas (S. capitata, S. potentilloides, S.ruthiae y S. simplex) habían sido previamente consideradas como miembros de Artemisia (A. capitata, A. potentilloides, A. ruthiae y A. simplex, respectivamente), por lo quese recomienda utilizar su nomenclatura anteriorThis work was subsidized by projects CGL2007-64839-C02-01/BOS and CGL2007-64839-C02-02/BOS of the Spanish government. SG was granted a JAE-DOC contract from the CSIC and a short stay in the Shrub Sciences Laboratory (USDA) in Utah, also from the CSIC.Peer reviewe

RCLUS, A NEW PROGRAM FOR CLUSTERING ASSOCIATED SPECIES: A DEMONSTRATION USING A MOJAVE DESERT PLANT COMMUNITY DATASET

This paper presents a new clustering program named RCLUS that was developed for species (R-mode) analysis of plant community data. RCLUS identifies clusters of co-occurring species that meet a user-specified cutoff level of positive association with each other. The "strict affinity" clustering algorithm in RCLUS builds clusters of species whose pairwise associations all exceed the cutoff level, whereas the "coalition" clustering algorithm only requires that the mean pairwise association of the cluster exceeds the cutoff level. Both algorithms allow species to belong to multiple clusters, thus accommodating both generalist and specialist species. Using a 60-plot dataset of perennial plants occurring on the Beaver Dam Slope in southwestern Utah, we carried out RCLUS analyses and compared the results with 2 widely used clustering techniques: UPGMA and PAM. We found that many of the RCLUS clusters were subsets of the UPGMA and PAM clusters, although novel species combinations were also generated by RCLUS. An advantage of RCLUS over these methods is its ability to exclude species that are poorly represented in a dataset as well as species lacking strong association patterns. The RCLUS program also includes modules that assess the affinity of a given species, plot, or environmental variable to a given cluster. We found statistically significant correlations between some of the RCLUS species clusters and certain environmental variables of the study area (elevation and topographical position). We also noted differences in clustering behavior when different association coefficients were used in RCLUS and found that those incorporating joint absences (e.g., the phi coefficient) produced more clusters and more even numbers of species per cluster than those not incorporating joint absences (e.g., the Jaccard index). In addition to the species association application described in this paper, the RCLUS algorithms could be used for preliminary data stratification in sample (Q-mode) analysis. The indirect link between sample plots and RCLUS species clusters could also be exploited to yield a form of "fuzzy" classification of plots or to characterize species pools of plots

Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

Characteristics and hybridization of important intermountain shrubs.

no.22

WINTERING MULE DEER PREFERENCE FOR 21 ACCESSIONS OF BIG SAGEBRUSH

Volume: 46Start Page: 281End Page: 28

KARYOTYPES OF FOUR ARTEMISIA SPECIES: A. CARRUTHII, A. FILIFOLIA, A. FRIGIDA, AND A. SPINESCENS

Volume: 39Start Page: 419End Page: 42

'Rincon' Fourwing Saltbush—Proven for Better Forage and Reclamation

This material was digitized as part of a cooperative project between the Society for Range Management, the National Agricultural Library, and the University of Arizona Libraries.The Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform March 202