Small Stream Valley Research Articles

거제도 여차 해안의 제4기 퇴적 지형 형성과정

The Quaternary depositional landforms such as coastal alluvial fans and marine terraces had been developed in Yeocha Coast, the southern part of Geoje Island. The coastal alluvial fan 2 was formed in MIS 6 and alluvial fan 1 was formed in MIS 4. It is interpreted that all alluvial fans were deposited with sediments including angular gravels supplied by physical weathering and mass movement along small stream valley. The marine terrace 1 and 2 appear as bedrock erosional surfaces. In particular, the marine terrace 1 is distributed at above sea level of 7~10m, and it is estimated to be formed in transgression periods of MIS 5a.

Soils of slopes and bottomland positions of the small stream valley in the central forest reserve: Chemical properties and clay mineralogy

Pale-podzolic soils occupying slope positions in a small stream valley are more acidic and contain less pedogenic chlorites in the clay fraction than those soils occupying uplands. These characteristics are thought to be caused by more intensive leaching of matter from eluvial horizons due to intensive lateral interflow of soil water. Soddy-gleyic soils of the stream bottomland are rich in organic matter and have a slightly acidic reaction in the A1 horizon and an alkaline reaction in the calcareous subsoil. Both factors lead to accumulation of Feox and Alox supplied to bottomland positions from uplands and slopes and those formed in situ.

Water Dispersal Potential of Fruits of Dirca palustris L. (Thymeleaceae)

Dispersal of propagules by water, or hydrochory, is a primary or secondary dispersal mode for many plant species that live in or near aquatic habitats. Buoyancy of seeds and fruits is a key attribute in hydrochory; the longer a propagule remains afloat, the greater the likelihood that it will be carried some distance from its source by flowing or pulsing water or by wind-generated surface currents (Shimamura et al. 2007). Studies of hydrochory in plants often initially focus on quantifying the buoyancy of propagules in laboratory settings to assess the water dispersal potential of a species (e.g., Williamson and Costa 2000). Plants that use hydrochory for propagule dispersal often occur in habitats that are flooded at seasonal or daily intervals (Schneider and Sharitz 1998, Williamson and Costa 2000, Moegenburg 2002, Shimamura et al. 2007). In many hydrochorous species, especially those of seasonally inundated habitats, fruit production often peaks during flooding events, which maximizes the potential for dispersal (Williamson and Costa 2000, Moegenburg 2002). Eastern leatherwood or wicopy, Dirca palustris L. (Thymeleaceae), is a shrub that occurs in rich, mesic forests in eastern North America, especially along streams (Nevling 1962, Ward and Horn 1998, Williams and Moriarity 1998). On the Allegheny High Plateau of northwestern Pennsylvania, D. palustris is among the earliest of species to flower in the region, usually in early to mid-April (Williams 2004). The fruit, an ellipsoid, greenishyellow drupe 8 to 12 mm in length, matures in May and is dispersed from shrubs during June. Little is known about the dispersal ecology of the fleshy fruits of D. palustris. Fruits are thought to be dispersed by frugivorous birds and mammals, gravity, and water (Ward and Horn 1998). In this note, I examine the potential for hydrochory in D. palustris based on field observations of shrub spatial patterning and laboratory studies of fruit and seed buoyancy. In the small stream valleys where Dirca palustris occurs in northwestern Pennsylvania (Williams and Moriarity 1998, Williams 2004), peak flows and potential for flooding typically occur after snowmelt in March to early April. Relative to hydrochory, these seasonal high flows are out of synchrony with the June fruiting season of the species, which occurs when most regional streams are beginning to reach base flow. The classic coupling of high flow events and propagule dispersal often seen in ‘‘typical’’ hydrochorous plants is lacking for D. palustris in small stream valleys of the region and likely elsewhere in its range. Our examination of the distribution of individuals of a Dirca palustris population along Sibbald Run (Forest County, Pennsylvania), in the Allegheny National Forest, suggests that proximity of shrubs to the stream could enhance the potential for hydrochory in this species during base flow periods. The population hub of D. palustris in this valley consists of over 50 individuals located along approximately 100 m of stream [see Williams and Moriarity (1998) and Williams (2004) for a description of the study area]. In early April 2000, we measured the distance of all D. palustris individuals (n 5 54) from the stream and noted their flowering status (flowering, non-flowering). We found that 55.6% of individuals in this population occurred within 2 m of the stream bank (Figure 1) and that nearly all individuals (97.0%) were in flower. Much of the potential source of fruits in this *email address: chuckvt89@gmail.com Present address: Western Pennsylvania Conservancy, 40W. Main Street, Ridgway, Pennsylvania 15853. Received 25 August, 2008; Accepted 17 January, 2009. CASTANEA 74(4): 372–375. DECEMBER 2009

Spatially distributed temperatures at the base of two mountain snowpacks measured with fiber-optic sensors

AbstractSnowpack base temperatures vary during accumulation and diurnally. Their measurement provides insight into physical, biological and chemical processes occurring at the snow/soil interface. Recent advances in Raman-spectra instruments, which use the scattered light in a standard telecommunications fiber-optic cable to infer absolute temperature along the entire length of the fiber, offer a unique opportunity to obtain basal snow temperatures at resolutions of 1 m, 10 s and 0.1°C. Measurements along a 330 m fiber over 24 hours during late-spring snowmelt at Mammoth Mountain, California, USA, showed basal snow temperatures of 0 ± 0.2°C using 10 s averages. Where the fiber-optic cable traversed bare ground, surface temperatures approached 40°C during midday. The durability of the fiber optic was excellent; no major damage or breaks occurred through the winter of burial. Data from the Dry Creek experimental watershed in Idaho across a small stream valley showed little variability of temperature on the northeast-facing, snow-covered slope, but clearly showed melting patterns and the effects of solar heating on southwest-facing slopes. These proof-of-concept experiments show that the technology enables more detailed spatial and temporal coverage than traditional point measurements of temperature.

Elk browsing increases aboveground growth of water-stressed willows by modifying plant architecture

In the northern elk wintering range of Yellowstone National Park, USA, wolf (Canis lupus) removal allowed elk (Cervus elaphus) to overbrowse riparian woody plants, leading to the exclusion of beaver (Castor canadensis) and a subsequent water table decline in many small stream valleys. Reduced elk browsing following wolf reintroduction may or may not facilitate willow (Salix sp.) recovery in these areas. To determine if the effect of elk browsing on willow interacts with that of beaver abandonment, we manipulated elk browsing and the water table in a factorial experiment. Under the condition of an ambient (low) water table, elk browsing increased shoot water potential (Psis), photosynthesis per unit leaf area (A), stomatal conductance per unit leaf area (gs), and aboveground current annual growth (CAG) by 50%. Elk browsing occurred entirely during dormancy and did not affect total plant leaf area (L). Improved water balance, photosynthetic rate, and annual aboveground productivity in browsed willows appeared to be due to morphological changes, such as increased shoot diameter and decreased branching, which typically increase plant hydraulic conductivity. An elevated water table increased Psis, A, gs, CAG, and L, and eliminated or lessened the positive effect of browsing on CAG for most species. Because low water tables create conditions whereby high willow productivity depends on the morphological effects of annual elk browsing, removing elk browsing in areas of water table decline is unlikely to result in vigorous willow stands. As large willow standing crops are required by beaver, a positive feedback between water-stressed willow and beaver absence may preclude the reestablishment of historical conditions. In areas with low water table, willow restoration may depend on actions to promote the re-establishment of beaver in addition to reducing elk browsing.

Mating system and pollination biology of the spring‐flowering shrub, Dirca palustris

Abstract Dirca palustris L., eastern leatherwood or wicopy (Thymelaeaceae), a widely distributed shrub of eastern North America, flowers in early spring and so may face some of the same constraints faced by ephemeral vernal herbs of the eastern deciduous forest, most notably the influence of low temperature on pollinator activity. I studied the mating system of D. palustris and the influence of temperature on pollinator visitation of flowers, during three field seasons in a small stream valley in north‐western Pennsylvania, USA. Specifically, I was interested in how a species with apparently specialized floral morphology, like D. palustris, may ensure reproductive success in a thermally unpredictable vernal environment. Pollinator visitation of flowers of D. palustris was strongly regulated by temperature, with no visits occurring below 14.9°C. Lack of treatment effects in mating system studies, especially the lack of significant differences in fruit set between the bagged, self‐pollination treatment and various cross‐pollination treatments accessible to pollinators, suggests that D. palustris is self‐compatible or perhaps apomictic. Thus, like other spring‐flowering species faced with pollinator unpredictability, D. palustris may rely on a mixed mating system to ensure reproductive success during cool temperate springs.

The Grayling Fingers region of Michigan: soils, sedimentology, stratigraphy and geomorphic development

This paper provides data on the landforms, soils, and sediments within a unique northern Michigan landscape known as the Grayling Fingers, and evaluates these data to develop various scenarios for the geomorphic development of this region. Composed of several large, flat-topped ridges that trend N–S, the physiography of the “Fingers” resembles a hand. Previously interpreted as “remnant moraines”, the Grayling Fingers are actually a Pleistocene constructional landscape that was later deeply incised by glacial meltwater. The sediments that comprise the Fingers form a generally planar assemblage, with thick (>100 m), sandy glacial outwash forming the lowest unit. Above the outwash are several meters of till that is remarkably similar in texture to the outwash below; thus, the region is best described as an incised ground moraine. Finally, a thin silty “cap” is preserved on the flattest, most stable uplands. This sediment package and the physiography of the Fingers are suggestive of geomorphic processes not previously envisioned for Michigan. Although precise dates are lacking, we nonetheless present possible sequences of geomorphic/sedimentologic processes for the Fingers. This area was probably a topographic high prior to the advance of marine isotope stage 2 (Woodfordian) ice. Much of the glacial outwash in the Fingers is probably associated with a stagnant, early Woodfordian ice margin, implying that this interlobate area remained ice-free and ice-marginal for long periods during stage 2. Woodfordian ice eventually covered the region and deposited 5–10 m of sandy basal till over the proglacial outwash plain. Small stream valleys on the outwash surface were palimpsested onto the till surface as the ice retreated, as kettle chains and as dry, upland valleys. The larger of these valleys were so deeply incised by meltwater that they formed the large, through-flowing Finger valleys. The silt cap that occupies stable uplands was probably imported into the region, while still glaciated. The Fingers region, a col on the ice surface, could have acted as a collection basin for silts brought in as loess or in superglacial meltwater. This sediment was let down as the ice melted and preserved only on certain geomorphically stable and fluvially isolated locations. This study demonstrates that the impact of Woodfordian ice in this region was mostly erosional, and suggests that Mississippi Valley loess may have indirectly impacted this region.

The fluvial morphodynamics of two small permafrost drainage basins, Richardson Mountains, Northwestern Canada

AbstractBased on hydrological fieldwork in the tundra of northwestern Canada during the springs of 1986, 1990, 1992, and 1994 and the summers of 1998, 1999, and 2000 the paper deals with the fluvial processes induced by spring snowmelt and by summer rainfall in two small stream valleys. At the end of winter the floors of these flat‐bottomed valleys are covered by icings (aufeis) over most of their length. The biggest quantity of meltwater runoff passes in an ice channel on top of the icing, with flow velocities up to 4.8 m/s. The main solid‐sediment transport takes place through the short runoff interval, when the stream channel has entrenched the aufeis in some places. The calculated suspended load transport during snowmelt flood varied from 62–313 t/km2 in different years. In summer, suspended‐sediment transport varies between 0.2–1.4 t/km2. There are no data about the frequency of exceptionally strong precipitation events, similar to those that occurred during the 1999 summer in the Douglas Creek basin that led to a suspended load transport of 153 t/km2 and a bedload transport of 444 t/km2 in about 12 days. The average annual suspended‐sediment yield for Andy Creek is 71 t/km2/yr, and 328 t/km2/yr for Douglas Creek. The average annual solutes yield for Andy Creek is 19 t/km2/yr, and 52 t/km2/yr for Douglas Creek. If one includes the hardly‐recordable bedload transport, the total equivalent surface lowering rate by fluvial solids transport is about 350 mm/1000yr for the Andy Creek basin and 850 mm/1000yr for the Douglas Creek basin. Copyright © 2002 John Wiley & Sons, Ltd.

A Prehistoric Ford near Rough Castle, Falkirk

This report presents the results of the excavation of a stone ford laid across the base of a small stream valley near Rough Castle, Falkirk. It was discovered during an opencast coal mining project. Radiocarbon dates and pollen analysis of deposits overlying the ford combine to indicate a date for its construction no later than the early first millennium cal BC. Interpreting this evidence was not straightforward and the report raises significant issues about site formation processes and the interpretation of radiocarbon and pollen evidence. The importance of these issues extends beyond the rarely investigated features such as fords and deserve a larger place in the archaeological literature.

Site Selection, Design, and Reclamation of the Winding Gulf Refuse Pile, Raleigh County, West Virginia

The Winding Gulf refuse pile is an abandoned coal refuse facility which stores about 505,000 cubic yards of coal refuse. The pile was placed indiscriminately across a small stream valley as the Beckley coal seam was mined in the area from the 19209s to the 19509s. Since it blocks the natural drainage of a small watershed, this non-engineered structure has been categorized by the West Virginia Department of Natural Resources as being of “high hazard potential.” This has necessitated relocation of the refuse material. Field observations and subsurface drilling performed by the authors indicate the material to be fairly uniform in nature and composition. Results of a washability study indicate that about 50 percent of the pile material can be recovered as a salable product if the pile was reprocessed at a separation gravity of 1.6. The separated coal product would have a heating value of 13,500 BTU/lb. and an ash content of 9.5 percent. The refuse remaining after reprocessing would be disposed of at a new site. Engineering tests on the separated refuse show it to be a well to poorly graded sand and gravel with non-plastic fines. Laboratory densities range from 91 pcf to 115 pcf. Specific gravity ranges from 1.85 to 2.30. Direct shear test results show friction angles between 33 degrees and 42 degrees with little or no cohesion. Triaxial tests on two samples show effective friction angles of 19 degrees and 14 degrees and effective cohesion of 1,080 and 1,025 psf, respectively. Slake durability tests indicate high to very high resistance to slaking. Design of a new refuse facility at a newly selected site was accomplished using the “REAME” computer model developed by Huang. The “REAME” program analyzes embankment slopes for different conditions using the Simplified Bishop Method of Slices. Based on stability analyses, an embankment containing three lifts, each 50 ft high and placed at 2.5 to 1 slopes, has been recommended. The proposed embankment design also includes plans for diversion drainage.

A Checklist of Ferns in Lincoln Parish, Louisiana

central Louisiana. Consideration of distribution of fern species in this region has been neglected except for incomplete references made by Brown and Correll (1942) and Moore (1956). The present study was initiated to prepare a checklist of species and their habitats within Lincoln Parish. Lincoln Parish is located in the central part of north Louisiana (Lat. 32?27' to 32?45'N and Long. 92025' to 92?55'W). The terrain consists of low, rolling, sandy or clay hills. The present vegetation is mainly second growth coniferous forest, with hardwood species restricted to small stream valleys and in related swampy or boggy regions. A preliminary survey indicated the existence of a number of probable fern habitats, such as open fence rows, open woodland, dense woodland, open bogs, and shaded bogs. The selection of twelve sites for examination and collection of fern species was made to include all the habitat types. Prior to 1962, ten fern species had been reported from this area. These were: Osmunda cinnamomea, Athyrium filix-femina, Thelypteris hexagonoptera, Polystichum acrostichoides, Pteridium aquilinum var. pseudocaudatum (Brown & Correll, 1938); Botrychium virginianum, Botrychium dissectum var. obliquum, Woodwardia areolata, Onoclea sensibilis, and Polypodium polypodiodes (Moore, 1956). During the present study, six species previously unreported from this area were found: Aspleniuim platyneuron, Osmunda regalis var. spectabilis, Woodwardia virginica, Thelypteris normalis, Ophioglossulm vulgatum, and Cystopteris fragilis. In addition, the reported, but unconfirmed, presence of the following species were noted: Woodsia obtusa, Athyrium thelypterioides, Adiantum pedatum, and Lygodilum japonicum. 33