Patterns of conifer establishment and vigor on montane river floodplains in Olympic National Park, Washington, USA

2010 ◽  
Vol 40 (3) ◽  
pp. 410-422 ◽  
Author(s):  
Scott A. Stolnack ◽  
Robert J. Naiman

In the Pacific Coastal Ecoregion, coniferous trees are often prescribed for riparian restoration, yet little is known about their establishment on floodplains under natural conditions. In this study, 10- to 50-year-old floodplain surfaces of six rivers were surveyed to (1) quantify conifer distribution along study reaches, (2) describe relationships between conifer presence and selected biological and environmental variables, and (3) compare growth rates and relative vigor of conifers among sites. We found conifers on 17%–36% of the plots we sampled. Sitka spruce ( Picea sitchensis (Bong.) Carrière) was most common on the wetter sites, while Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco) was most common on the drier sites. Other conifers common to adjacent terraces were extremely rare. Douglas-fir preferred elevated sites with shallower soils and fewer hardwood competitors (e.g., Alnus rubra Bong. and Salix spp.) than similar plots without conifers. For Sitka spruce, the variables examined revealed no statistical differences between conifer and non-conifer plots. Our findings suggest that the tolerance of Douglas-fir to drier conditions allows it to survive on relatively higher, drier sites where more moisture-demanding competitors fail. For Sitka spruce, factors other than those measured appear to be more important in spruce establishment and survival.

1984 ◽  
Vol 60 (6) ◽  
pp. 345-355 ◽  
Author(s):  
R. van den Driessche

In three experiments coastal and interior varieties of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco). Sitka spruce (Picea sitchensis (Bong.) Carr), white spruce (Picea glauca (Moench.) Voss), lodgepole pine (Pinus contorta var. latifolia Engelm) and western red cedar (Thuja plicata Donn.) were grown at a range of spacings, within drills 15 cm apart, at four nurseries in coastal British Columbia. In a fourth experiment the frequency distribution of seed spacings achieved with three types of precision seeders was examined.A 1 cm increase in spacing increased seedling dry weight by 0.5–1.5 g and root collar diameter by 0.2–0.25 mm. up to a spacing of about 8–10 cm. Above this spacing response was less. Height of two-year old (2-0) seedlings was increased little, or even decreased by wider spacing. Height:diameter ratios decreased sharply and shoot:root dry weight ratios decreased or remained unchanged with wider spacing. The number of needle primorida in 2-0 Douglas-fir buds increased up to a spacing of 2 cm. The number of first and second order branches was also increased in 2-0 seedlings of this species by wider spacing. Needle dry weight and area measurements suggested Douglas-fir from wider spacing had more sun type needles than those from closer spacing, which had more shade type needles. Only small increases in root growth capacity (RGC) were associated with wider spacing. None of the precision seeders tested achieved anything like perfect precision of seed placement. With irregularity added by 10–20% non-viable seed and winter mortality, truly precision spaced stands of 2-0 seedlings could not be achieved under existing conditions. Increased spacing of 2–5 cm between seedlings, depending on species and nursery, was justified by yield of acceptable seedlings when culling standard was increased to a root collar diameter of about 6 mm.Three years after planting, survival of white spruce was increased 11% by wider spacing in the nursery, and the corresponding value for Sitka spruce two years after planting was 13%. Seedlings of both species from wider spacings maintained a height and diameter advantage over those from close spacing.


2000 ◽  
Vol 30 (5) ◽  
pp. 817-826 ◽  
Author(s):  
H A Cárcamo ◽  
T A Abe ◽  
C E Prescott ◽  
F B Holl ◽  
C P Chanway

Laboratory experiments were conducted with the millipede Harpaphe haydeniana haydeniana Wood (Polydesmida: Xystodesmidae) to determine (i) its litter feeding preferences, (ii) rates of leaf litter consumption, (iii) feeding effects on available nitrogen, and (iv) functional microbial diversity. The millipede exhibited a preference for Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and, to a lesser extent, Sitka spruce (Picea sitchensis (Bong.) Carrière) litter compared with western hemlock (Tsuga heterophylla (Raf.) Sarg.) and western redcedar (Thuja plicata Donn ex D. Don) litter when given a choice. When only one litter type was provided, millipedes consumed considerably more western redcedar than Douglas-fir, Sitka spruce, or western hemlock. Among the six broadleaf species tested, paper birch (Betula papyrifera Marsh.), bigleaf maple (Acer macrophyllum Pursh), vine maple (Acer circinatum Pursh), and red alder (Alnus rubra Bong.) were consumed at much higher rates than swordfern (Polystichum munitum (Kaulf.) Presl.) or salal (Gaultheria shallon Pursh). Daily rates of conifer litter consumption ranged between 10 and 20% of the millipede's fresh biomass and may translate to 36% of the annual litter fall. Our results suggest that transformation of conifer litter into millipede frass can increase rates of litter decomposition and N mineralization, as well as influence microbial activity and diversity in coastal forests.


2001 ◽  
Vol 31 (2) ◽  
pp. 246-260 ◽  
Author(s):  
Hua Chen ◽  
Mark E Harmon ◽  
Robert P Griffiths

Decomposition of woody roots in Sitka spruce (Picea sitchensis (Bong.) Carrière), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), and ponderosa pine (Pinus ponderosa P. Laws. ex C. Laws.) dominated forests in Oregon, U.S.A. was studied using a chronosequence. Roots of five coniferous species were excavated from stumps with ages up to 46 years old. In order of increasing decomposition rate constant (k) the species were Douglas-fir < Sitka spruce < lodgepole pine (Pinus contorta Dougl. ex Loud.) < western hemlock (Tsuga heterophylla (Raf.) Sarg) < ponderosa pine. Variation in the proportion of bark, wood, and resin cores was correlated to these differences. Root wood showed the highest k, root bark the second, and resin cores the lowest. The occurrence of resin cores in woody roots of Douglas-fir, Sitka spruce, and lodgepole pine greatly slowed the decomposition of these species. White rots occurred frequently in ponderosa pine and lodgepole pine, whereas brown rots mostly appeared in Douglas-fir and Sitka spruce. Species with white rot had a higher k than those with brown rot. Decomposing woody roots started to release N after 20–30% mass loss, a point when the dead root C/N ratio averaged 140.


1998 ◽  
Vol 28 (5) ◽  
pp. 665-673 ◽  
Author(s):  
Robert L Edmonds ◽  
David S Lebo

Fungal sporocarps were sampled on 47 logs in six 0.1-ha plots in an old-growth Sitka spruce (Picea sitchensis (Bong.) Carr.) - western hemlock (Tsuga heterophylla (Raf.) Sarg.) forest in the Hoh River Valley, Olympic National Park, Washington, from October 1993 to May 1994. Log biomass averaged 205 Mg/ha and the surface area of plots occupied by logs was 9.8%. Most fungal fruiting occurred on decay class 3 logs, the most common type on a scale from 1 (least decayed) to 5 (most decayed). Eighty-two taxa of fleshy fungi (63 saprophytic, 18 mycorrhizal, and one pathogenic) and six taxa of large annual or perennial fungi occurred on logs. Most fungi were basidiomycetes. Highest fleshy sporocarp production occurred in fall (456 g/ha) rather than spring (40 g/ha). Ischnoderma resinosum had the highest annual production (88 g/ha). Concentrations of N, P, K, Ca, Mg, Mn, Na, Fe, Zn, Al, B, and Cu in fruiting bodies were determined. Lower N concentrations occurred in perennial fungi (0.45%) than mycorrhizal (4.33%) and fleshy saprophytic species (3.30%). Only a small fraction of the nutrient capital in the logs was exported to the forest floor in fungal sporophores.


2011 ◽  
Author(s):  
Jessica E. Halofsky ◽  
David L. Peterson ◽  
Kathy A. O’Halloran ◽  
Catherine Hawkins Hoffman

2018 ◽  
Vol 10 (11) ◽  
pp. 12451-12458 ◽  
Author(s):  
Rama Mishra ◽  
Khadga Basnet ◽  
Rajan Amin ◽  
Babu Ram Lamichhane

The Fishing Cat is a highly specialized and threatened felid, and its status is poorly known in the Terai region of Nepal.  Systematic camera-trap surveys, comprising 868 camera-trap days in four survey blocks of 40km2 in Rapti, Reu and Narayani river floodplains of Chitwan National Park, were used to determine the distribution and habitat characteristics of this species.  A total of 19 photographs of five individual cats were recorded at three locations in six independent events.  Eleven camera-trap records obtained during surveys in 2010, 2012 and 2013 were used to map the species distribution inside Chitwan National Park and its buffer zone.  Habitat characteristics were described at six locations where cats were photographed.  The majority of records were obtained in tall grassland surrounding oxbow lakes and riverbanks.  Wetland shrinkage, prey (fish) depletion in natural wetlands and persecution threaten species persistence.  Wetland restoration, reducing human pressure and increasing fish densities in the wetlands, provision of compensation for loss from Fishing Cats and awareness programs should be conducted to ensure their survival.  We also recommend studying genetic diversity of sub-populations, as well as habitat use by radio-tagging. 


Holzforschung ◽  
2010 ◽  
Vol 64 (4) ◽  
Author(s):  
J. Paul McLean ◽  
Robert Evans ◽  
John R. Moore

Abstract Sitka spruce (Picea sitchensis) is the most widely planted commercial tree species in the United Kingdom and Ireland. Because of the increasing use of this species for construction, the ability to predict wood stiffness is becoming more important. In this paper, a number of models are developed using data on cellulose abundance and orientation obtained from the SilviScan-3 system to predict the longitudinal modulus of elasticity (MOE) of small defect-free specimens. Longitudinal MOE was obtained from both bending tests and a sonic resonance technique. Overall, stronger relationships were found between the various measures of cellulose abundance and orientation and the dynamic MOE obtained from the sonic resonance measurements, rather than with the static MOE obtained from bending tests. There was only a moderate relationship between wood bulk density and dynamic MOE (R2=0.423), but this relationship was improved when density was divided by microfibril angle (R2=0.760). The best model for predicting both static and dynamic MOE involved the product of bulk density and the coefficient of variation in the azimuthal intensity profile (R2=0.725 and 0.862, respectively). The model parameters obtained for Sitka spruce differed from those obtained in earlier studies on Pinus radiata and Eucalyptus delegatensis, indicating that the model might require recalibration before it can be applied to different species.


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