Relationship of Forest Road Aggregate Test Properties to Sediment Production

2001 ◽  
Author(s):  
Randy B. Foltz ◽  
Gary L. Evans ◽  
Mark Truebe
Keyword(s):  
Forest Road ◽  
Sediment Production ◽  
Relationship Of

The Assessment of Sediment Production Yield from Forest Road Using Sediment Prediction Model

2008 ◽  
Vol 8 (10) ◽  
pp. 1944-1949 ◽  
Author(s):  
Hossein Khalilpoor ◽  
Seyed Ataollah Hosseini ◽  
Majid Lotfalian ◽  
Yahya Kooch
Keyword(s):  
Prediction Model ◽  
Production Yield ◽  
Forest Road ◽  
Sediment Production

Locally Available Aggregate and Sediment Production

2003 ◽  
Vol 1819 (1) ◽  
pp. 185-193 ◽  
Author(s):  
Randy B. Foltz ◽  
Mark Truebe
Keyword(s):  
Road Construction ◽  
Forest Road ◽  
Sediment Production ◽  
Magnitude Range ◽  
Long Duration ◽  
Order Of Magnitude ◽  
Equivalent Test ◽  
Basic Characteristics ◽  
Material Tests ◽  
Selection Of

Selection of suitable locally available materials to build strong and durable roads with aggregate surfaces is desired to minimize road construction and maintenance costs and to minimize the detrimental effects of sedimentation. Eighteen aggregates were selected from local sources in Idaho, Oregon, South Dakota, and Washington State. Aggregate was placed in shallow metal frames and compacted to simulate a forest road. The levels of runoff and sediment from a highintensity, long-duration simulated rainstorm were measured. The material tests selected for use in the study included ones that define the basic characteristics of the aggregate, along with a number of tests intended to predict susceptibility to erosion. Each of the tests was statistically evaluated to identify those that best predicted the perceived aggregate quality. The two best indicators of aggregate quality were the results of the sand equivalent test and the P20 portion of the Oregon air degradation test. The best indicator of either runoff or sediment production was the fraction passing the 0.6-mm sieve. Acceptable aggregates, both those of good quality and those of marginal quality, exhibited a 2-order-of-magnitude range in both runoff and sediment production.

Sediment production from forest road surfaces

1984 ◽  
Vol 20 (11) ◽  
pp. 1753-1761 ◽  
Author(s):  
Leslie M. Reid ◽  
Thomas Dunne
Keyword(s):  
Forest Road ◽  
Sediment Production ◽  
Road Surfaces

The relationship of gully sidewall shape to sediment production

Soil Research ◽  
1987 ◽  
Vol 25 (4) ◽  
pp. 531 ◽  
Author(s):  
RJ Crouch
Keyword(s):  
Erosion Rate ◽  
New South ◽  
Sediment Sources ◽  
Relative Significance ◽  
Sediment Production ◽  
Lack Of Information ◽  
South Wales ◽  
Erosion Pins ◽  
Relationship Of ◽  
The Relationship

Reports of gully side erosion describe a range of side forms. The lack of information on the relative significance of the various forms in terms of sediment production hinders the identification of the major sediment sources within gullies. Observations of gully sides in a catchment in central New South Wales showed a range of side forms being eroded at significantly different rates. Side classification and measurement by survey and erosion pins showed that vertical sides, subject to undercutting, had the highest erosion rate (75 mm yr-l) followed by vertical fluted walls (37 mm yr-l). These different rates are critical in predicting present and future rates of erosion and identifying sediment sources within gully systems.

The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
Author(s):  
William A. Oliver
Keyword(s):  
Critical Points ◽  
Scleractinian Corals ◽  
Convincing Evidence ◽  
Early Triassic ◽  
Rugose Corals ◽  
History Of ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

Studies on Leukemogenic and Sarcomagenic Viruses

1970 ◽  
Vol 28 ◽  
pp. 156-157
Author(s):  
Leon Dmochowski
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Morphological Properties ◽  
Mode Of Development ◽  
Relationship Of ◽  
The Relationship

Electron microscopy has proved to be an invaluable discipline in studies on the relationship of viruses to the origin of leukemia, sarcoma, and other types of tumors in animals and man. The successful cell-free transmission of leukemia and sarcoma in mice, rats, hamsters, and cats, interpreted as due to a virus or viruses, was proved to be due to a virus on the basis of electron microscope studies. These studies demonstrated that all the types of neoplasia in animals of the species examined are produced by a virus of certain characteristic morphological properties similar, if not identical, in the mode of development in all types of neoplasia in animals, as shown in Fig. 1.

The relationship of IGE receptor topography to signaling activity in RBL-2H3 mast cells

1991 ◽  
Vol 49 ◽  
pp. 236-237
Author(s):  
J.R. Pfeiffer ◽  
J.C. Seagrave ◽  
C. Wofsy ◽  
J.M. Oliver
Keyword(s):  
Mast Cells ◽  
Protein A ◽  
Scattered Electron ◽  
Ige Receptor ◽  
Receptor Complexes ◽  
Ige Binding ◽  
Electron Imaging ◽  
Small Clusters ◽  
Relationship Of ◽  
The Relationship

In RBL-2H3 rat leukemic mast cells, crosslinking IgE-receptor complexes with anti-IgE antibody leads to degranulation. Receptor crosslinking also stimulates the redistribution of receptors on the cell surface, a process that can be observed by labeling the anti-IgE with 15 nm protein A-gold particles as described in Stump et al. (1989), followed by back-scattered electron imaging (BEI) in the scanning electron microscope. We report that anti-IgE binding stimulates the redistribution of IgE-receptor complexes at 37“C from a dispersed topography (singlets and doublets; S/D) to distributions dominated sequentially by short chains, small clusters and large aggregates of crosslinked receptors. These patterns can be observed (Figure 1), quantified (Figure 2) and analyzed statistically. Cells incubated with 1 μg/ml anti-IgE, a concentration that stimulates maximum net secretion, redistribute receptors as far as chains and small clusters during a 15 min incubation period. At 3 and 10 μg/ml anti-IgE, net secretion is reduced and the majority of receptors redistribute rapidly into clusters and large aggregates.

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