Field study of plant survival as affected by amendments to bentonite spoil

Efforts to reclaim amended and raw bentonite spoils with six plant species (two forbs, three shrubs, and one tree) were evaluated over a 4-year period. Plant species included fourwing saltbush ( Atriplex canescens [Pursh] Nutt.), big sagebrush ( Artemisia tridentata tridentata Nutt.), Rocky Mountain Juniper ( Juniperus scopulorum Sarg.), Russian olive ( Elaeagnus angustifolia L.) common yarrow ( Achillea millifolium L.) and scarlet globemallow ( Sphaeralcea coccinea [Pursh] Rydb.). Spoil treatments included addition of gypsum, sawdust, perlite, straw, and vermiculite; the control treatment was amended. Fourwing saltbush had 52% survival across all spoil treatments, with greatest survival occurring on perlite-treated spoil (80%), followed by gypsum (70%) and vermiculite amendments (70%). Survival of other plant species ranged from 0 to 2% averaged across all treatments after 4 years. No differences in plant survival occurred among amendments when all species were considered.     

Response of understory species to changes in ponderosa pine stocking levels in the Black Hills

The objective of this study was to test the hypothesis that there are no differences in understory production, by species, due to stocking levels of Pinus ponderosa (ponderosa pine). Understory production was estimated, by species, on 3 replicates each of 8 growing stock levels, ranging from clearcuts to unthinned stands, in both sapling- and pole-sized pine stands (48 plots) over 3 nonconsecutive years. All stands were approximately 70 yr old when thinning treatments were applied. Production of many herbaceous species, especially Agropyron spp. (wheatgrasses) and Carex spp. (sedges), declined as growing stock levels (measured in terms of basal area) of ponderosa pine increased. While trends in total production were similar, there were specific differences between sapling and pole stands. Sedges and Oryzopsis asperfolia (roughleaf ricegrass) produced more in sapling stands, whereas Danthonia intermedia (timber oatgrass) was more abundant in pole stands. Shrub production, dominated by Acrtostaphylos uva-ursi (bearberry), was relatively consistent across all stocking levels except unthinned. Although the total number of species declined as pine basal area increased, a few species, such as Linnaea borealis (twinflower) and Shepherdia canadensis (buffaloberry), were found only under relatively dense pine canopies. While floristic species richness was greater at lower stocking levels of ponderosa pine, the total number of species would be greater if all stocking levels were present.     

Association of black-tailed prairie dog colonies with cattle point attractants in the Northern Great Plains

In October 1991 we recorded all black-tailed prairie dog ( Cynomys ludovicianus ) colonies and cattle points in a 1248-km 2 study area in southwest North Dakota and southeast Montana. Cattle point attractants were defined as fabricated water tanks and long-term supplemental feed sites. We found that a signivicant number of prairie dog colonies encompassed or adjoined cattle point attractants ( p < .001). Prairie dog colonies associated with cattle point attractants were a mean distance of 1.0 km from the next nearest town. The existence of cattle point attractants may encourage prairie dog colonization. Conversely, refraining from using long-term cattle point attractants can discourage prairie dog colonization.     

Indicators of red squirrel (Tamiasciurus hudsonicus) abundance in the whitebark pine zone

We investigated occupied squirrel middens and squirrel sightings and vocalizations as indicators of red squirrel ( Tamiasciurus hudsonicus ) abundance in high-elevation whitebark pine ( Pinus albicaulis ) zone. Data were collected 1984-1989 from line transects located on 2 study sites in the Yellowstone ecosystem. We evaluated the performance of each measure on the basis of precision and biological considerations. We concluded that, of the 3 measures, active middens were the best indicator of red squirrel abundance. We also observed that the density of active middens dropped by 48%-66% between 1987 and 1989, following a severe drought and extensive wildfires that burned one of the study sites during 1988.     

Arylsulfatase B synthesis and clearance in inbred mouse strains

Arylsulfatase B activity levels were approximately 2-3-fold higher in adult C57BL/6J liver and kidney compared to corresponding tissues from A/J inbred mice. In vivo incorporation of tritiated leucine into C57BL/6J hepatic arylsulfatase B reached a maximum approximately 15 h after injection. The label was cleared from C57BL/6J arylsulfatase B with an apparent half-life of 36 h. The relative rates of synthesis of C57BL/6J and A/J arylsulfatase B were similar; however, the A/J enzyme was cleared more rapidly from liver tissue. C57BL/6J kidney arylsulfatase B appeared to be synthesized at a 2-3-fold higher rate than the corresponding A/J enzyme. These trends suggest genetic regulation of arylsulfatase B is effected through different means in liver and kidney from adult mice of these two inbred strains.     

Experimental study in rats to reduce carbon monoxide in the blood induced by cigarette smoke, by inhaling oxygen at atmospheric pressure]

When animals are exposed to cigarette smoke, the concentration of carbon monoxide in blood is rapidly increased, so that intensive inhalation tests cannot be carried out. A simple apparatus is described to expose Rats alternatively to cigarette smoke and to oxygen in order to reduce the concentration of carbon monoxide in the blood. This method makes it possible to increase the daily administration of smoke considerably; nevertheless, under such conditions, lung tumors were not observed.     

Murine arylsulfatase C: Evidence for two isozymes

Summary SWR/J mice posses high arylsulfatase C, estrone sulfatase, and dehydroepiandrosterone sulfatase activities in liver, spleen and kidney compared to A/J mice. This internstrain activity variation appears to be determined by at least 1 autosomal gene. Murine arylsulfatase C activity occurs in both hydrophobic and hydrophilic forms which differ with respect to certain biochemical properties and exhibit different subcellular distributions. The hydrophilic isozyme is a major component in kidney and brain extracts and a minor isozyme in liver and spleen extracts. The hydrophobic arylsulfatase C isozyme appears to be identical to steroid sulfatase. The hydrophilic arylsulfatase C isozyme does not possess steroid sulfatase activity; however, hydrophilic and hydrophobic arylsulfatase C share certain properties, suggesting that they may be structurally related. The autosomal gene(s) affects both arylsulfatase isozymes.This research was supported in part by National Institutes of Health grant GM 27707.     

Mammalian arylsulfatases A and B: relative rates of hydrolysis of artificial substrates

Summary Rodent and bovine arylsulfatase B hydrolyze 4-methylumbelliferyl sulfate (4MUS) 10- to 30-fold more efficiently than arylsulfatase A. Therefore, 4MUS grossly underestimates arylsulfatase A activity in the presence of excess arylsulfatase B.