Recommendation of RILEM TC 271-ASC: New accelerated test procedure for the assessment of resistance of natural stone and fired-clay brick units against salt crystallization

This recommendation is devoted to testing the resistance of natural stone and fired-clay brick units against salt crystallization. The procedure was developed by the RILEM TC 271-ASC to evaluate the durability of porous building materials against salt crystallization through a laboratory method that allows for accelerated testing without compromising the reliability of the results. The new procedure is designed to replicate salt damage caused by crystallization near the surface of materials as a result of capillary transport and evaporation. A new approach is proposed that considers the presence of two stages in the salt crystallization test. In the first, the accumulation stage, salts gradually accumulate on or near the surface of the material due to evaporation. In the second, the propagation stage, damage initiates and develops due to changes in moisture content and relative humidity that trigger salt dissolution and crystallization cycles. To achieve this, two types of salt were tested, namely sodium chloride and sodium sulphate, with each salt tested separately. A methodology for assessing the salt-induced damage is proposed, which includes visual and photographical observations and measurement of material loss. The procedure has been preliminarily validated in round robin tests

Recommendation of RILEM TC 271-ASC: New accelerated test procedure for the assessment of resistance of natural stone and fired-clay brick units against salt crystallization

This recommendation is devoted to testing the resistance of natural stone and fired-clay brick units against salt crystallization. The procedure was developed by the RILEM TC 271-ASC to evaluate the durability of porous building materials against salt crystallization through a laboratory method that allows for accelerated testing without compromising the reliability of the results. The new procedure is designed to replicate salt damage caused by crystallization near the surface of materials as a result of capillary transport and evaporation. A new approach is proposed that considers the presence of two stages in the salt crystallization test. In the first, the accumulation stage, salts gradually accumulate on or near the surface of the material due to evaporation. In the second, the propagation stage, damage initiates and develops due to changes in moisture content and relative humidity that trigger salt dissolution and crystallization cycles. To achieve this, two types of salt were tested, namely sodium chloride and sodium sulphate, with each salt tested separately. A methodology for assessing the salt-induced damage is proposed, which includes visual and photographical observations and measurement of material loss. The procedure has been preliminarily validated in round robin tests

Mule deer-induced mortality of mountain big sagebrush

A fence line contrast was provided by a deer fence that bisected a mountain big sagebrush (Artemisia tridentata ssp. vaseyana) community. The sagebrush community was located on an exposed, west-facing slope that was generally swept free of snow during the severe winters of 1982-83 and 1983-84. On the freeway side of the fence, the site was essentially free of browsing animals, while above the fence, the shrubs were exposed to concentrations of mule deer (Odocoileus hemionus). Considerable big sagebrush mortality was evident after the 2 successive winters of heavy snowfall. Big sagebrush mortality and partial dieback of portions of the canopy were significantly (P<0.05) higher in the portion of the community exposed to browsing. Herbaceous species composition also differed between the protected and browsed areas with a higher portion of annual species found in the browsed community. A large number of big sagebrush seedlings germinated in 1984, but failed to establish by 1986. Excessive use of native plants by native large herbivores can have lasting effects on plant communities.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management 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 August 202

Growth Performance Comparisons among 18 Accessions of Fourwing Saltbush (Atriplex canescens) at Two Sites in Central Utah

Growth characteristics of 17 accessions and 1 selection of fourwing saltbush (Atriplex canescens [Pursh] Nutt.) at 2 sites in Sanpete Valley, central Utah, were scored on 6-year-old mature plants. There was no difference in survival at the 2 sites, but plants at the Snow Field Station near Ephraim grew taller, were more vigorous, and exhibited more reproductive capacity than those at the Peacock Plot near Manti. The plants at Peacock Plot had a more upright growth habit, were more uniform, and exhibited less insect and disease damage than the Snow Field Station plants. A composite quality index (QI) revealed highly significant site and accession differences but little site × accession interaction. The individual traits (height, growth habit, uniformity, vigor, reproduction, and insect and disease damage resistance) all showed significant site effects and site × accession interaction. An accession and its selection from Rincon Blanco, Rio Arriba County, New Mexico, performed well at both sites. Also performing well at both sites were a local accession from Excell Canyon, Sanpete County, Utah, and the gigas accession from the Little Sahara Sand Dunes, Juab County, Utah. In general, accessions from elevations higher than the test sites performed best. Accessions with high QI's are recommended for revegetation plantings of sites comparable to the 2 study sites. The Rincon Blanco material has good growth characteristics and may also be broadly adapted.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management 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 August 202

Contributions to the Taxonomy of Chrysothamnus viscidiflorus (Astereae compositae) and Other Chrysothamnus Species Using Paper Chromatography

Chromatographic patterns of phenolic compounds were determined for each of the common subspecies of the widespread range shrub Chrysothamnus viscidiflorus (low rabbitbrush), some other Chrysothamnus taxa, and some related Compositae genera. Each subspecies of C. viscidiflorus exhibited variation across its geographical range, but within sites the patterns were consistent. Chromatographic pattern distributions suggest a predominance of self-pollination in C. viscidiflorus; however, the limited outcrossing has important genetic implications. Analysis of the chromatographic spot patterns revealed three groups or clusters within C. viscidiflorus. Surprisingly, C. greenei clustered more closely to some C. viscidiflorus subspecies than these subspecies clustered with other C. viscidiflorus subspecies. C. greenei clustered with ssp. lanceolatus and stenophyllus. Ssp. viscidiflorus clustered s > 0.70 with ssp. latifolius and a group of collections intermediate in morphology between viscidiflorus and lanceolatus. It shares some intense spots with these taxa. Subspecies puberulus did not cluster at s = > 70 with any other taxon. Chromatographic data supported the independent species status of C. linifolius and the internal integrity of the three large species complexes in Chrysothamnus-C. viscidiflorus, C. nauseosus, and C. parryi. The genus Petradoria had high a values with Chrysothamnus, as did Haplopappus bloomeri. Other shrubby Compositae (Xanthocephalum sarothrae and Lepidospartum latisquamum) had much lower s values with Chrysothamnus. Chromatography complements morphology in delimiting taxonomic rank. Each Chrysothamnus taxon should be evaluated on its merits.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management 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 August 202

Chromatographic Recognition of Some Palatable and Unpalatable Subspecies of Rubber Rabbitbrush in and around Utah

Paper chromatography is useful in identifying palatable and unpalatable subspecies of rubber rabbitbrush in Utah. Methanol extraction of dried foliar material followed by two-dimensional (n-butanol:acetone:water, 4:1:3; acetic acid:water, 15:85) ascending paper chromatography reveals distinctive patterns for Chrysothamnus nauseosus subspecies albicaulis, salicifolius, graveolens, and consimilis. Patterns for rarer subspecies junceus and hololeucus are not as well defined. Gene exchange between subspecies is demonstrated by chemical markers, the chromatographic spots, in putative hybrids and introgressents. Range utilization of current growth by browsing animals is highest for subspecies albicaulis and salicifolius, less for subspecies graveolens, and least for subspecies consimilis. Populations of other subspecies introgressed by consimilis receive limited browsing. Paper chromatography will make it possible to select palatable subspecies of rubber rabbitbrush for range improvement projects and nonpalatable subspecies for areas where animal use is to be discouraged.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management 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 August 202