scholarly journals Rarity and nutrient acquisition relationships before and after prescribed burning in an Australian box-ironbark forest

AoB Plants ◽  
2018 ◽  
Vol 10 (3) ◽  
Author(s):  
John Patykowski ◽  
Matt Dell ◽  
Tricia Wevill ◽  
Maria Gibson
Keyword(s):  
Prescribed Burning ◽  
Nutrient Acquisition ◽  
Before And After

Effects of Forest Fires on Archaeological Resources at Grand Canyon National Park

1987 ◽  
Vol 7 (3) ◽  
pp. 243-254 ◽  
Author(s):  
Anne Trinkle Jones ◽  
Robert C. Euler
Keyword(s):  
Forest Fires ◽  
Fire History ◽  
Prescribed Burning ◽  
Grand Canyon ◽  
Cultural Resources ◽  
Experimental Conditions ◽  
The North ◽  
Before And After ◽  
History Of ◽  
Fire Area

For a number of years archaeologists have discussed the effects of forest fires on archaeological resources. Studies under experimental conditions and of sites after they were burned form the bulk of this effort but, for the most part, they have not been published. This article examines the fire history of the North Rim of the Grand Canyon and the effects of the Dutton Point wildfire on prehistoric architecture and artifacts—particularly ceramics. Armed with those data, a modest experiment useful in any proposed prescribed fire area containing cultural resources, was designed. This involved “before and after” studies of a ruin that was to be subjected to prescribed burning and included buried temperature controls and the varying effects upon the resource. Finally, a hypothesis regarding the effect of wildfires on archaeological sites is presented.

The Effect of Cutting and Burning on Browse Production in Eastern Canadian Aspen Forests

1991 ◽  
Vol 1 (1) ◽  
pp. 41 ◽  
Author(s):  
MG Weber
Keyword(s):  
Odocoileus Virginianus ◽  
Biomass Production ◽  
Untreated Control ◽  
Nutrient Concentration ◽  
Prescribed Burning ◽  
Control Area ◽  
Post Treatment ◽  
Before And After ◽  
Spring Leaf ◽  
Leaf Flush

A 20-year-old aspen (Populur tremloides Michx.) ecosystem was subjected to two cutting and two burning treatments. Cutting and prescribed burning were carried out on separate areas . One cutting and one burning treatment was aplied both before and after spring leaf flush. An untreated control area was set aside for comparison. Three years after treatment summer and winter aspen browse production for moose (Alcesaices) and white-tailed deer (Odocoileus virginianus) were greatest on the preflush cutting treatment (summer — 1544 kg.ha-1; winter — 395 kgha-1) followed in decreasing order by post-flush cut (summer — 635 kg.ha-1; winter — 125 kg.ha-1), postflush burn (summer — 330 kg.ha-1; winter — 96 kg.ha-1), and pre-flush burn (summer — 50 kg.ha-1; winter — no browsing). Aspen browse quality (nutrient concentration) was essentially unaffected by treatment. Post treatment biomass production of aspen is discussed in terms of known physiological and ecological responses to disturbance.

Hydrologic and mineral budgets of New Jersey Pine Barrens upland forests following two intensities of fire

1982 ◽  
Vol 12 (3) ◽  
pp. 503-510 ◽  
Author(s):  
Ralph E. J. Boerner ◽  
R. T. T. Forman
Keyword(s):  
New Jersey ◽  
Prescribed Burning ◽  
Control Site ◽  
Fire Intensity ◽  
Late Winter ◽  
Pine Barrens ◽  
Prescribed Burn ◽  
Fire Adaptations ◽  
Forest Sites ◽  
Before And After

The hydrologic and mineral budgets of upland forest sites in the New Jersey Pine Barrens exposed to different fire intensities were determined. Inputs from bulk precipitation and outputs to groundwater were monitored in an unburned control site, two sites burned by severe wildfire, and two sites burned by light prescribed burning. Fluxes of water, calcium, magnesium, and potassium to groundwater were highest in wildfire sites, intermediate in prescribed burn sites, and lowest in the unburned control. At all sites, outputs were the greatest during late-winter snowmelt. In the unburned site, outputs were essentially absent during the growing season, whereas in the wildfire sites outputs to groundwater were present year round. Rates of mineral and water output were inversely proportional to biomass and forest floor mass, which in turn depended upon fire intensity. Relative increases in output were similar to those reported following fire in other ecosystems. However, absolute rates of mineral output both before and after fire were lower in these sandy soils than those reported elsewhere, probably due to the low total mineral storage and variety of fire adaptations present in the Pine Barrens ecosystem.

Deformation Replication

1970 ◽  
Vol 28 ◽  
pp. 280-281
Author(s):  
J. Temple Black
Keyword(s):  
Cutting Speed ◽  
Machining Process ◽  
Depth Of Cut ◽  
Rake Face ◽  
Orthogonal Machining ◽  
Aluminum Chips ◽  
Before And After ◽  
Materials Used ◽  
Glass Knife ◽  
Very High

Tool materials used in ultramicrotomy are glass, developed by Latta and Hartmann (1) and diamond, introduced by Fernandez-Moran (2). While diamonds produce more good sections per knife edge than glass, they are expensive; require careful mounting and handling; and are time consuming to clean before and after usage, purchase from vendors (3-6 months waiting time), and regrind. Glass offers an easily accessible, inexpensive material ($0.04 per knife) with very high compressive strength (3) that can be employed in microtomy of metals (4) as well as biological materials. When the orthogonal machining process is being studied, glass offers additional advantages. Sections of metal or plastic can be dried down on the rake face, coated with Au-Pd, and examined directly in the SEM with no additional handling (5). Figure 1 shows aluminum chips microtomed with a 75° glass knife at a cutting speed of 1 mm/sec with a depth of cut of 1000 Å lying on the rake face of the knife.

The Clinical, Roentgenological and Morphological Effects of an Acute Exposure of Phosgene on the Lungs of Dogs

1971 ◽  
Vol 29 ◽  
pp. 236-237
Author(s):  
R. F. Bils ◽  
W. F. Diller ◽  
F. Huth
Keyword(s):  
Latent Period ◽  
Chemical Industry ◽  
Toxic Substance ◽  
Lung Edema ◽  
X Rays ◽  
Beagle Dogs ◽  
Male And Female ◽  
Morphological Alterations ◽  
Before And After ◽  
Electron Microscopes

Phosgene still plays an important role as a toxic substance in the chemical industry. Thiess (1968) recently reported observations on numerous cases of phosgene poisoning. A serious difficulty in the clinical handling of phosgene poisoning cases is a relatively long latent period, up to 12 hours, with no obvious signs of severity. At about 12 hours heavy lung edema appears suddenly, however changes can be seen in routine X-rays taken after only a few hours' exposure (Diller et al., 1969). This study was undertaken to correlate these early changes seen by the roengenologist with morphological alterations in the lungs seen in the'light and electron microscopes.Forty-two adult male and female Beagle dogs were selected for these exposure experiments. Treated animals were exposed to 94.5-107-5 ppm phosgene for 10 min. in a 15 m3 chamber. Roentgenograms were made of the thorax of each animal before and after exposure, up to 24 hrs.

Ultrastructure of Melanin Formation in Curvularia sp., Alternaria sp., and Drechslera Sorokiniana

1977 ◽  
Vol 35 ◽  
pp. 398-399
Author(s):  
M. H. Wheeler ◽  
W. J. Tolmsoff ◽  
A. A. Bell
Keyword(s):  
Potassium Phosphate ◽  
Thielaviopsis Basicola ◽  
Wild Type ◽  
Potassium Phosphate Buffer ◽  
Transmission Microscopy ◽  
Electron Transmission ◽  
Melanin Formation ◽  
Before And After ◽  
Alternaria Sp ◽  
Electron Transmission Microscopy

(+)-Scytalone [3,4-dihydro-3,6,8-trihydroxy-l-(2Hj-naphthalenone] and 1,8-di- hydroxynaphthalene (DHN) have been proposed as intermediates of melanin synthesis in the fungi Verticillium dahliae (1, 2, 3, 4) and Thielaviopsis basicola (4, 5). Scytalone is enzymatically dehydrated by V. dahliae to 1,3,8-trihydroxynaphthalene which is then reduced to (-)-vermelone [(-)-3,4- dihydro-3,8-dihydroxy-1(2H)-naphthalenone]. Vermelone is subsequently dehydrated to DHN which is enzymatically polymerized to melanin.Melanin formation in Curvularia sp., Alternaria sp., and Drechslera soro- kiniana was examined by light and electron-transmission microscopy. Wild-type isolates of each fungus were compared with albino mutants before and after treatment with 1 mM scytalone or 0.1 mM DHN in 50 mM potassium phosphate buffer, pH 7.0. Both chemicals were converted to dark pigments in the walls of hyphae and conidia of the albino mutants. The darkened cells were similar in appearance to corresponding cells of the wild types under the light microscope.

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