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Journal articles on the topic "Large coarse wood"
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Scaranello, Marcos A. S., Michael Keller, Marcos Longo, Maiza N. dos-Santos, Veronika Leitold, Douglas C. Morton, Ekena R. Pinagé, and Fernando Del Bon Espírito-Santo. "Estimation of coarse dead wood stocks in intact and degraded forests in the Brazilian Amazon using airborne lidar." Biogeosciences 16, no. 17 (September 13, 2019): 3457–74. http://dx.doi.org/10.5194/bg-16-3457-2019.
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Abstract. Coarse dead wood is an important component of forest carbon stocks, but it is rarely measured in Amazon forests and is typically excluded from regional forest carbon budgets. Our study is based on line intercept sampling for fallen coarse dead wood conducted along 103 transects with a total length of 48 km matched with forest inventory plots where standing coarse dead wood was measured in the footprints of larger areas of airborne lidar acquisitions. We developed models to relate lidar metrics and Landsat time series variables to coarse dead wood stocks for intact, logged, burned, or logged and burned forests. Canopy characteristics such as gap area produced significant individual relations for logged forests. For total fallen plus standing coarse dead wood (hereafter defined as total coarse dead wood), the relative root mean square error for models with only lidar metrics ranged from 33 % in logged forest to up to 36 % in burned forests. The addition of historical information improved model performance slightly for intact forests (31 % against 35 % relative root mean square error), not justifying the use of a number of disturbance events from historical satellite images (Landsat) with airborne lidar data. Lidar-derived estimates of total coarse dead wood compared favorably with independent ground-based sampling for areas up to several hundred hectares. The relations found between total coarse dead wood and variables quantifying forest structure derived from airborne lidar highlight the opportunity to quantify this important but rarely measured component of forest carbon over large areas in tropical forests.
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Copoț, Ovidiu, and Cătălin Tănase. "Substrate properties, forest structure and climate influences wood-inhabiting fungal diversity in broadleaved and mixed forests from Northeastern Romania." Forest Systems 29, no. 3 (December 29, 2020): e021. http://dx.doi.org/10.5424/fs/2020293-16728.
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Aim of the study: The main objective of this study was to find the factors which best explains the wood-inhabiting fungal species’ richness in beech and oak-dominated forests.Area of study: We focused on broadleaved and mixed forests found in Northeastern Romania.Materials and methods: 59 plots were randomly set up in broadleaved and mixed forest stands, in which vegetation structure, composition, and topoclimatic factors were quantified along with wood-inhabiting fungal richness. Generalized linear models were used to characterize relationship between fungal diversity and biotic and abiotic factors.Main results: 374 taxa were identified, with numerous species found to cohabitate, the highest sharing being between Fine Woody Debris and Downed Coarse Woody Debris. The best predictors of total diversity were related to the substrate, management, stand structure, and macroclimate. Higher volumes of logs and large branches in various decay stages increased fungal richness. The same effect was found in diverse forests, with large snags. Macroclimate and topoclimate positively influenced diversity, through De Martonne Aridity Index and snow cover length, both indicating macrofungi preferences for higher moisture of substrate. Silvicultural interventions had an ambivalent effect to fungal diversity, phenomenon observed through stump numbers and proportion.Research highlights: Particular environmental characteristics proved significantly important in explaining different wood-inhabiting fungal richness patterns. Substrate-related variables were the most common ones found, but they were closely linked to climate and forest stand variables.Keywords: Wood-inhabiting fungi; oak, beech and coniferous forests; substrate diversity; dead wood types; coarse woody debris; fine woody debris; climatic variables.Abbreviations used:ALT, elevation; ASPI, Aspect Index; BIO1, mean annual temperature; BIO4, temperature seasonality; BIO7, annual temperature range; BIO12, annual precipitation; BIO15, precipitation seasonality; CWD, coarse woody debris; DBH, diameter at breast height; DCWD, downed coarse woody debris; DCWD_DECAY, DCWD decay diversity; DCWD_DIV, DCWD taxonomic diversity; DCWD_SV, surface-volume ratio of DCWD; DCWD_VOL, DCWD volume; DMAI, De Martonne Aridity Index; DMAI_AU, Autumn DMAI; DMAI_SP, Spring DMAI; DMAI_SU, Summer DMAI; DMAI_WI, Winter DMAI; FAI, Forestry Aridity Index; FWD, fine woody debris; L_SNAG_BA, large snag basal area; OLD_BA, basal area of old trees; POI, Positive Openness Index; RAI, Recent Activity Index; SCL, snow cover length; SLOPE, slope; SNAG_N, snag density; STUMP_N, stump density; TPI, Topographic Position Index; TREE_BA, mean basal area of trees; TREE_DIV, tree' Shannon diversity.
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Dai, Zhaohua, Carl C. Trettin, Andrew J. Burton, Martin F. Jurgensen, Deborah S. Page-Dumroese, Brian T. Forschler, Jonathan S. Schilling, and Daniel L. Lindner. "Coarse woody debris decomposition assessment tool: Model development and sensitivity analysis." PLOS ONE 16, no. 6 (June 4, 2021): e0251893. http://dx.doi.org/10.1371/journal.pone.0251893.
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Coarse woody debris (CWD) is an important component in forests, hosting a variety of organisms that have critical roles in nutrient cycling and carbon (C) storage. We developed a process-based model using literature, field observations, and expert knowledge to assess woody debris decomposition in forests and the movement of wood C into the soil and atmosphere. The sensitivity analysis was conducted against the primary ecological drivers (wood properties and ambient conditions) used as model inputs. The analysis used eighty-nine climate datasets from North America, from tropical (14.2° N) to boreal (65.0° N) zones, with large ranges in annual mean temperature (26.5°C in tropical to -11.8°C in boreal), annual precipitation (6,143 to 181 mm), annual snowfall (0 to 612 kg m-2), and altitude (3 to 2,824 m above mean see level). The sensitivity analysis showed that CWD decomposition was strongly affected by climate, geographical location and altitude, which together regulate the activity of both microbial and invertebrate wood-decomposers. CWD decomposition rate increased with increments in temperature and precipitation, but decreased with increases in latitude and altitude. CWD decomposition was also sensitive to wood size, density, position (standing vs downed), and tree species. The sensitivity analysis showed that fungi are the most important decomposers of woody debris, accounting for over 50% mass loss in nearly all climatic zones in North America. The model includes invertebrate decomposers, focusing mostly on termites, which can have an important role in CWD decomposition in tropical and some subtropical regions. The role of termites in woody debris decomposition varied widely, between 0 and 40%, from temperate areas to tropical regions. Woody debris decomposition rates simulated for eighty-nine locations in North America were within the published range of woody debris decomposition rates for regions in northern hemisphere from 1.6° N to 68.3° N and in Australia.
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Stewart, Bruce J., Peter D. Neily, Eugene J. Quigley, and Lawrence K. Benjamin. "Selected Nova Scotia old-growth forests: Age, ecology, structure, scoring." Forestry Chronicle 79, no. 3 (June 1, 2003): 632–44. http://dx.doi.org/10.5558/tfc79632-3.
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A study of four old-growth stands in Nova Scotia was conducted to document the ecological characteristics of these currently rare Acadian forest ecosystems. Stands were selected to represent the two dominant climax forest types, hemlock–red spruce–eastern white pine, and sugar maple–yellow birch–beech. Data include measurements of age structure, species composition, diameter distribution, basal area, height, coarse woody debris, snags, vertical structure, and canopy condition. All stands were determined to be uneven-aged. Old-growth reference ages calculated for the stands ranged from 164 to 214 years. All stands displayed broad diameter distributions that had peak basal area representation in the 40- to 50-cm diameter classes. Volumes of dead wood ranged from 111 to 148 m3/ha in the softwood stands and from 63 to 83m3/ha in the hardwood stands. Dead wood consisted of approximately one-third snags and two thirds downed coarse woody debris. Measurements from the stands were used to evaluate Nova Scotia's recently developed Old Forest Scoring System. Six stand attributes were rated for a maximum score of 100: stand age, primal value, number of large-diameter trees, length of large-diameter dead wood, canopy structure, and understorey structure. Based on the age attribute, three of the four stands were classed as Mature Old Growth and one was very close, indicating that all are in the shifting mosaic stage of late forest succession. The scores for all stands were relatively high, ranging from 75 to 85, as would be expected from some of the best old-growth stands in the province. Key words: old growth, climax, primal, late succession, uneven-aged, scoring, coarse woody debris, age structure, diameter, Acadian forest, northern hardwood, red spruce, eastern hemlock, white pine, sugar maple, yellow birch, American beech
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Stewart, Glenn H., and Larry E. Burrows. "Coarse woody debris in old-growth temperate beech (Nothofagus) forests of New Zealand." Canadian Journal of Forest Research 24, no. 10 (October 1, 1994): 1989–96. http://dx.doi.org/10.1139/x94-255.
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The volume, biomass, and carbon and nitrogen content of coarse woody debris were measured on three 1-ha reference plots in old-growth Nothofagusfusca (Hook. f.) Oerst.–Nothofagusmenziesii (Hook. f.) Oerst. forest on the South Island of New Zealand. Two decay sequences for logs and one for standing dead trees (snags) were recognised from two-way indicator species analysis (TWINSPAN) of up to 30 variables related to physical characteristics and structural integrity. Wood volume (up to 800 m3•ha−1) and biomass were high (up to 300 Mg•ha−1), and the inside-out decay sequence from heartwood to sapwood was unusual compared with that of other temperate hardwood forests. Coarse woody debris represented significant carbon and nitrogen pools, with ca. 150 Mg•ha−1 and 370 kg•ha−1, respectively, in one stand. The coarse woody debris component of these broad-leaved evergreen hardwood forests was much higher than that reported for other temperate hardwood forests and approaches that of many northern hemisphere conifer forests. The large coarse woody debris pools are discussed in relation to live stand biomass, natural disturbances and tree mortality, and decomposition processes.
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Wang, Fei, Qiu Liang Zhang, Xiao Mei Li, Chun Sheng Bao, and Xiao Wei Gao. "Characteristics of Coarse Woody Debris in Different-Age Natural Larix gmelinii Forests in Daxing’anling Mountains." Advanced Materials Research 347-353 (October 2011): 107–11. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.107.
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Coarse woody debris (CWD) is composed of dry wood, fallen wood and large branches, and it is an important element for structure and function in forest ecosystems. In this paper, we studied the characteristics of coarse woody debris (CWD) of natural Larix gmelinii forests with different ages in Daxing’anling Mountains. The results show that (1) the CWD volumes in near-mature, middle-age and young forests are 88.55 m3•hm-2, 52.07 m3•hm-2 and 3.96 m3•hm-2, respectively; and their biomasses are 52.96 t•hm-2, 36.22 t•hm-2 and 2.35t•hm-2, respectively. Which indicate that the CWD volumes and biomasses increase with forest ages addition; (2) The CWD volume and biomass follow normal distribution in middle and near-mature forest; (3) the CWD volume and biomass decrease with forest age increasing within decay classes I and II, whereas increase in decay classes III, IVand V; (4) the volume of middle-age and young forests present a near normal distribution with decay class increasing.
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Bunnell, Fred L., and Isabelle Houde. "Down wood and biodiversity — implications to forest practices." Environmental Reviews 18, NA (December 2010): 397–421. http://dx.doi.org/10.1139/a10-019.
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Many species require or use down wood (fine and coarse woody debris) as habitat. Where forestry has been practiced for several rotations large proportions of these species are considered threatened. Key attributes determining the suitability of down wood as habitat are decay stage, tree species, and size, specifically diameter. Both quantity and distribution of suitable down wood influence species’ presence and abundance. We present a simple framework describing use of down wood based on broad natural history features, derive predictions from the framework, then test these by review and summary of literature. Our focus is terrestrial vertebrates, particularly in the Pacific Northwest. Species other than vertebrates are addressed to ensure that metrics derived for vertebrates also are appropriate for other organisms. Basic metrics are the same, but appropriate values span a larger range among nonvertebrates. Current evidence suggests that the “extinction debt” apparent for nonvertebrates is approaching for vertebrates. Predictions derived from underlying natural history hold when tested. From that basis we derive broad guidelines for forest planning and practice, and suggest how regional target values can be derived.
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Marañón-Jiménez, Sara, Jorge Castro, Emilia Fernández-Ondoño, and Regino Zamora. "Charred wood remaining after a wildfire as a reservoir of macro- and micronutrients in a Mediterranean pine forest." International Journal of Wildland Fire 22, no. 5 (2013): 681. http://dx.doi.org/10.1071/wf12030.
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Large amounts of logs and coarse woody debris remain in the ecosystem after wildfires. However, the relevance of the nutrient reservoir contained in the remaining post-fire woody debris for the ecosystem nutrient reserves is rarely considered. In this paper, we determine the carbon and nutrient concentrations in the partially charred wood after a wildfire along an altitudinal gradient and assess the relative magnitude of the nutrient reservoir in the wood in relation to those existing in the first 10-cm soil layer. Soils were poorly developed and nutrients limiting for the vegetation requirements. Charred woody material still contained a relatively high concentration of nutrients compared to those reported for unburnt pine wood, and in general, this decreased with altitude. Partially charred wood represented a considerable pool of nutrients, due to both the relatively high concentrations and to the great amount of biomass still present after the fire. Potential contributions of the charred wood were particularly relevant for N and micronutrients Na, Mn, Fe, Zn and Cu, as wood contained 2–9 times more nutrients than the soil. Post-fire woody debris constitutes therefore a valuable natural element as a potential source of nutrients, which would be lost from ecosystems in cases where it is removed.
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Caron, Jean, Louis-Marie Rivière, and Gilles Guillemain. "Gas diffusion and air-filled porosity: Effect of some oversize fragments in growing media." Canadian Journal of Soil Science 85, no. 1 (February 1, 2005): 57–65. http://dx.doi.org/10.4141/s03-086.
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Large particles are often added to growing media to improve air-filled porosity, an often-reported growth-limiting factor. Previous studies have shown that large fragments can leave air-filled porosity unchanged and actually decrease the air exchange characteristics in peat:bark and pure peat media, with an adverse effect on plant growth. Thirteen different growing mixes composed of perlite, bark, peat, sand, rockwool, wood and coco fibre, in which the size of the larger fractions was varied, were tested. Air-filled porosity, easily available water, pore effectiveness coefficient, and diffusivity were examined in these mixes. Air-filled porosity was found to be the highest in mixes where the largest fraction was composed of coarser particles. Pore effectiveness coefficient was found to decrease with the increasing coarseness of the largest fractions. Gas diffusivity was found to be highest when intermediate (2–4 mm) fragments were used as the largest fraction of the mixes. These findings applied to impermeable, disk- or spherically shaped, coarse fragments (perlite, coco hulls, bark), but did not apply to threadlike coarse material (wood fibres). Gas diffusivity values (at a water potential of −0.75 kPa) obtained for rockwool, the peat:bark mix containing 2- to 4-mm bark particles, the peat:medium wood fibre mix, the peat:fine perlite (0.8–2 mm) mix and the pure fine coconut medium were not statistically different one from another. Air-filled porosity was negatively correlated to the fractions less than 1 mm, between 0 and 0.2 mm and between 0.2 and 0.8 mm. Easily available water, pore effectiveness coefficient and gas diffusivity were not correlated to particle size distribution, indicating that these properties cannot be estimated based on particle size and must instead be measured directly. Key words: Aetion, peat substrates, perlite, bark, available water
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Lõhmus, Asko, and Piret Lõhmus. "Coarse woody debris in mid-aged stands: abandoned agricultural versus long-term forest land." Canadian Journal of Forest Research 35, no. 6 (June 1, 2005): 1502–6. http://dx.doi.org/10.1139/x05-047.
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During the 20th century, large agricultural areas in Eastern Europe became forested after their abandonment. To explore the value of these new forests for biota, we assessed volumes of coarse woody debris (CWD) on random transects in mid-aged (4075 years old) stands. In mixed and deciduous forests that were not forested in the 1930s, downed tree (log) volumes were about two times lower than in cutover sites. The effect on snag volume depended on site type and was generally nonsignificant. Large-diameter CWD showed similar proportions in the long-term and new forest areas, but large, well-decayed trunks tended to be less frequent in the latter. No reduction of dead wood volume was found in new pine stands, 98% of which had previously been classified as mires (bogs). Hence the origin of mid-aged successional forests had affected their CWD supply (particularly logs) to some extent, but the general scarcity of CWD all over the forest land indicated much larger (at least five-fold) losses due to timber harvesting. We conclude that naturally reforested areas should not be automatically excluded from reserve establishment or other CWD-related conservation programmes.
Dissertations / Theses on the topic "Large coarse wood"
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Latterell, Joshua J. "The natural history and dynamics of large wood in the Queets River, Washington /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/5273.
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Fox, Martin J. "Spatial organization, position, and source characteristics of large woody debris in natural systems /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/5463.
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Bambrick, Beth Marie. "Large Woody Debris Mobility Areas in a Coastal Old-Growth Forest Stream, Oregon." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/658.
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This study uses a spatial model to visualize LWD mobility areas in an approximate 1km reach of Cummins Creek, a fourth-order stream flowing through an old-growth Sitka spruce-western hemlock forest in the Oregon Coast Range. The model solves a LWD incipient motion equation for nine wood size combinations (0.1m, 0.4m, 1.7m diameters by 1.0m, 6.87m, 47.2m lengths) during the 2-year, 10-year, and 100-year discharge events. Model input variables were derived from a combination of field survey, remotely sensed, and modeled data collected or derived between June 2010 and July 2011. LWD mobility map results indicate the 2-year discharge mobilizes all modeled diameters, but mobile piece lengths are shorter than the bankfull channel boundary. Mobility areas for each wood size combination increases with discharge; 10-year and 100-year discharge events mobilize wood longer than average bankfull width within a confined section of the main stem channel, and mobilize LWD shorter than bankfull width within the main stem channel, side channels, and floodplain. No discharge event mobilizes the largest LWD size combination (1.7m / 47.2). Recruitment process was recorded for all LWD during June 2010, revealing that all mobile wood in the study reach was shorter than bankfull width. Based on these conflicting results, I hypothesize the distribution of wood in Cummins Creek can be described in terms of discharge frequency and magnitude, instead of as a binary mobile/stable classification. Mobility maps could be a useful tool for land managers using LWD as part of a stream restoration or conservation plan, but will require additional calibration.
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Hess, Jacquelyn Marie. "Distribution and residence times of large woody debris along South River, Shenandoah Valley, Virginia." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 184 p, 2007. http://proquest.umi.com/pqdweb?did=1400957071&sid=6&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Treadwell, Simon Andrew 1968. "Patterns in community metabolism and biomass of biofilms colonising large woody debris along an Australian lowland river." Monash University, Dept. of Biological Sciences, 2002. http://arrow.monash.edu.au/hdl/1959.1/5605.
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Chapman, Linnaea R. A. "The long-term availability of large woody debris in logged stream channels and second-growth riparian forests on the west coast of Vancouver Island." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ39179.pdf.
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Sass, Emma. "Lasting Legacies of Hurricane, Harvesting, and Salvage Logging Disturbance on Succession and Structural Development in an Old-Growth Tsuga canadensis-Pinus strobus Forest." ScholarWorks @ UVM, 2017. http://scholarworks.uvm.edu/graddis/817.
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Disturbance events affect forest composition and structure across a range of spatial and temporal scales, and forest development may differ after natural, anthropogenic, or compound disturbances. Following large, natural disturbances, salvage logging is a common yet controversial management practice around the globe. While the short-term impacts of salvage logging have been studied in many systems, the long-term effects remain unclear. Further, while natural disturbances create many persistent and unique microsite conditions, little is known about the long-term influence of microsites on forest development. We capitalized on over eighty years of data on stand development following the 1938 hurricane in New England to provide the longest known evaluation of salvage logging impacts, as well as to highlight developmental trajectories for eastern hemlock (Tsuga canadensis)-white pine (Pinus strobus) forests under a variety of disturbance histories. Eight decades following disturbance, there were no differences in current overstory composition between areas that were logged, hurricane disturbed, or hurricane disturbed and salvage logged, but white pine declined across most sites. In contrast, structural characteristics remain distinct between the three management histories. In the unsalvaged area, the diversity of microsites and the coverage of uprootings and pits influenced overstory tree composition, diversity, and structural characteristics. These findings underscore the long-term influence of salvage logging on forest development and the importance of natural disturbance-mediated microsite conditions on tree species growth and survival. Future salvage logging efforts should consider these impacts and provide a greater range of unsalvaged areas across the landscape to maintain these important structural legacies over the long term.
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Clark, Steven (Steven Michael). "Breeding site selection by coho salmon (Oncorhynchus kisutch) in relation to large wood additions and factors that drive reproductive success." Thesis, 2013. http://hdl.handle.net/1957/38182.
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The fitness of female Pacific salmon (Oncorhynchus spp.) with respect to breeding behavior can be partitioned into at least four components: survival to reproduction, competition for breeding sites, success of egg incubation, and suitability of the local environment near breeding sites for early rearing of juveniles. Accordingly, breeding sites should exhibit predictable habitat features linked to these components. In this study, I evaluated the relative influences of habitat features linked to fitness components on selection of breeding sites by coho salmon (Oncorhynchus kisutch). I also evaluated associations between breeding site selection and additions of large wood, as the latter were introduced into the study system as a means of restoring habitat conditions to benefit coho salmon. I used a model selection approach to organize specific habitat features into groupings reflecting fitness components and influences of large wood. The relative likelihood of each of these models was then evaluated based on how coho salmon were observed to select breeding sites. Specific variables examined within these models included depth at the redd, width to depth ratio, stream network location, proximity to other redds, maximum depth, proximity to a pool tail, and the count of naturally occurring and artificially placed large wood. Results of this work suggest that female coho salmon most likely select breeding sites based on habitat features linked to all four hypothesized fitness components. Linkages between large wood and breeding site selection were less clear, likely due to mismatches between the scale at which availability was quantified relative to the geomorphic influences of wood, insufficient time for wood to have geomorphic influences on habitat, or the directionality in which geomorphic effects are currently manifested (i.e., upstream, downstream, or bi-directional influences). Future work focused on geomorphic processes in this system could reveal stronger linkages between instream wood and the habitat features that coho salmon select for breeding.Graduation date: 2013
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Long, Barry A. "Recruitment and abundance of large woody debris in an Oregon coastal stream system /." 1987. http://hdl.handle.net/1957/9555.
Full textBooks on the topic "Large coarse wood"
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Lassettre, Neil S. Process based management of large woody debris at the basin scale, Soquel Creek, California: Report presented to California Dept. of Forestry and Fire Protection and Soquel Demonstration State Forest. [Sacramento, Calif.]: State of California, California Dept. of Forestry and Fire Protection, 2003.
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Wallerstein, N. P. An experimental study of alluvial channel response to large woody debris. Oxford, Mississippi: Channel & Watershed Processes Research Unit, National Sedimentation Laboratory, 1999.
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Tripp, D. B. Using large organic debris to restore fish habitat in debris-torrented streams. Victoria, B.C: Ministry of Forests and Lands, 1986.
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Bragg, Don C. Modeling large woody debris recruitment for small streams of the central Rocky Mountains. Fort Collins, CO: United States Dept. of Agriculture, Forest Service, Rocky Mountain Research Station, 2000.
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Bragg, Don C. Modeling large woody debris recruitment for small streams of the central Rocky Mountains. Fort Collins, CO: U.S. Dept. of Agriculture, Forest Service, Rocky Mountain Research Station, 2000.
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Streamside buffers and large woody debris recruitment: Evaluating the effectiveness of watershed analysis prescriptions in the North Cascades region. [Olympia, Wash.]: Timber, Fish, Wildlife, 2000.
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Lombard, Pamela J. The effect of the size and orientation of large wood on pool volume in two Oregon Coast Range streams. 1997.
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Clark, Nicola. Gender, Family, and Politics. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198784814.001.0001.
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Among the depositions taken as part of the Queen Catherine Howard treason case in 1541 is an illuminating exchange. Mary Hall/Lascelles, the originator of the reports of Catherine’s pre-marital sexual liaisons, claimed to have warned Henry Mannox, Catherine’s virginals tutor, to steer clear of Catherine, because ‘she do cu[m] of anobull hous & yf thow shuld mare here su[m] of here blod wold kell the’. Mannox coarsely replied, ‘hold thy pese woman I know here welhenoveghe for I have had here by thow count & know it amongst a C & she loff me & I lof her’. Mary clearly saw the Howard dynasty in this context as a large, cohesive entity primed to enact vengeance against those who wronged its members, and understood that women were among a dynasty’s chief assets. Mannox, on the other hand, disregarded this, and seemed to think that Catherine’s own individual feelings mattered more than what her family might think. These few sentences lay bare the inherent complexity of the early modern dynasty, and the importance of understanding the position of women within it: for, as this book argues, when women are placed centre stage it becomes evident that both of these interpretations of the function of an early modern dynasty could be valid, and that we need to nuance our understanding of women’s agency, dynastic identity, and politics to take account of this.
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Szewczyk, Janusz. Rola zaburzeń w kształtowaniu struktury i dynamiki naturalnych lasów bukowo-jodłowo-świerkowych w Karpatach Zachodnich. Publishing House of the University of Agriculture in Krakow, 2018. http://dx.doi.org/10.15576/978-83-66602-35-9.
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The aim of the study was to determine the influence of different disturbances (both natural and anthropogenic) on species composition and stand structure of old-growth mixed mountain forests in the Western Carpathians. These stands are usually dominated by beech, fir and spruce, mixed in different proportions. The tree main species represent different growth strategies, and they compete against each other. The longevity of trees makes the factors influencing the stand structure difficult to identify, even during longitudinal studies conducted on permanent research plots. That is why dendroecological techniques, based upon the annual variability of tree rings, are commonly used to analyze the disturbance histories of old-growth stands. Dendroecological methods make it possible to reconstruct the stand history over several centuries in the past by analyzing the frequency, intensity, duration and spatial scale of disturbances causing the death of trees. Combining the dendroecological techniques with the detailed measurements of stand structure, snag volume, CWD volume, and the analyses of regeneration species composition and structure allows us to identify the factors responsible for the changes in dynamics of mixed mountain forests. Various disturbance agents affect some species selectively, while some disturbances promote the establishment of tree seedlings of specific species by modifying environmental conditions. Describing the disturbance regime requires a broad scope of data on stand structure, on dead wood and tree regeneration, while various factors affecting all the stages of tree growth should be taken into consideration. On the basis of the already published data from permanent sample plots, combined with the available disturbance history analyses from the Western Carpathians, three research hypotheses were formulated. 1. The species composition of mixed mountain forests has been changing for at least several decades. These directional changes are the consequence of simultaneous conifer species decline and expansion of beech. 2. The observed changes in species composition of mixed mountain forests are the effect of indirect anthropogenic influences, significantly changing tree growth conditions also in the forests that are usually considered natural or near-natural. Cumulative impact of these indirect influences leads to the decrease of fir share in the tree layer (spruce decline has also been observed recently),and it limits the representation of this species among seedlings and saplings. The final effect is the decrease of fir and spruce share in the forest stands. 3. Small disturbances, killing single trees or small groups of trees, and infrequent disturbances of medium size and intensity dominate the disturbance regime in mixed mountain forests. The present structure of beech-fir-spruce forests is shaped both by complex disturbance regime and indirect anthropogenic influences. The data were gathered in permanent sample plots in strictly protected areas of Babia Góra, Gorce, and Tatra National Parks, situated in the Western Carpathians. All plots were located in the old-growth forest stands representing Carpathian beech forest community. The results of the measurements of trees, snags, coarse woody debris (CWD) and tree regeneration were used for detailed description of changes in the species composition and structure of tree stands. Tree ring widths derived from increment cores were used to reconstruct the historical changes in tree growth trends of all main tree species, as well as the stand disturbance history within the past two to three hundred years. The analyses revealed complex disturbance history in all of the three forest stands. Intermediate disturbances of variable intensity occurred, frequently separated by the periods of low tree mortality lasting from several decades up to over one hundred years. The intervals between the disturbances were significantly shorter than the expected length of forest developmental cycle, in commonly used theories describing the dynamics of old-growth stands. During intermediate disturbances up to several dozen percent of canopy trees were killed. There were no signs of stand-replacing disturbances, killing all or nearly all of canopy trees. The periods of intense tree mortality were followed by subsequent periods of increased sapling recruitment. Variability in disturbance intensity is one of the mechanisms promoting the coexistence of beech and conifer species in mixed forests. The recruitment of conifer saplings depended on the presence of larger gaps, resulting from intermediate disturbances, while beech was more successful in the periods of low mortality. However, in the last few decades, beech seems to benefit from the period of intense fir mortality. This change results from the influence of long-term anthropogenic disturbances, affecting natural mechanisms that maintain the coexistence of different tree species and change natural disturbance regimes. Indirect anthropogenic influence on tree growth was clearly visible in the gradual decrease of fir increments in the twentieth century, resulting from the high level of air pollution in Europe. Synchronous decreases of fir tree rings’ widths were observed in all three of the sample plots, but the final outcomes depended on the fir age. In most cases, the damage to the foliage limited the competitive abilities of fir, but it did not cause a widespread increase in tree mortality, except for the oldest firs in the BGNP (Babia Góra National Park) plot. BGNP is located in the proximity of industrial agglomeration of Upper Silesia, and it could be exposed to higher level of air pollution than the other two plots. High level of fir regeneration browsing due to the deer overabundance and insufficient number of predators is the second clear indication of the indirect anthropogenic influence on mixed mountain forests. Game impact on fir regeneration is the most pronounced in Babia Góra forests, where fir was almost completely eliminated from the saplings. Deer browsing seems to be the main factor responsible for limiting the number of fir saplings and young fir trees, while the representation of fir among seedlings is high. The experiments conducted in fenced plots located in the mixed forests in BGNP proved that fir and sycamore were the most preferred by deer species among seedlings and saplings. In GNP (Gorce National Park) and TNP (Tatra National Park), the changes in species composition of tree regeneration are similar, but single firs or even small groups of firs are present among saplings. It seems that all of the analysed mixed beech-fir-spruce forests undergo directional changes, causing a systematic decrease in fir representation, and the expansion of beech. This tendency results from the indirect anthropogenic impact, past and present. Fir regeneration decline, alongside with the high level of spruce trees’ mortality in recent years, may lead to a significant decrease in conifers representation in the near future, and to the expansion of beech forests at the cost of mixed ones.
Book chapters on the topic "Large coarse wood"
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"Landscape Influences on Stream Habitats and Biological Assemblages." In Landscape Influences on Stream Habitats and Biological Assemblages, edited by Lucinda B. Johnson, George E. Host, Jennifer H. Olker, and Carl Richards. American Fisheries Society, 2006. http://dx.doi.org/10.47886/9781888569766.ch8.
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<em>Abstract.</em>—Wood is an important component of small to medium-sized streams in forested regions, but has been poorly studied in agricultural areas. Our goals were to (1) characterize the abundance, size, and distribution of wood in low-gradient streams in two agricultural regions, (2) quantify the influence of reach- and landscape-scale factors on the abundance and distribution of wood in these streams, and (3) compare trends across two study areas. Wood abundance was quantified in stream reaches in two diverse agricultural regions of the Midwestern United States: central Michigan and southeastern Minnesota. Wood abundance was quantified in 71 stream reaches, and an array of channel, riparian zone, and landscape features were characterized. Multiple regressions were conducted to predict abundance from those explanatory variables. We found that large wood was relatively scarce in these low-gradient streams compared to low-gradient streams in forested regions. Mean log size was greater, but total abundance was lower in Minnesota than Michigan. In Minnesota, greatest wood abundance and greatest extent of accumulations were predicted in wide, shallow stream channels with high substrate heterogeneity and woody riparian vegetation overhanging the channel. Models were dominated by reach-scale variables. In Michigan, largest densities of wood and accumulations were associated with catchments in hilly regions containing urban centers, with low soil water capacity, wide, shallow stream channels, low coarse particular organic matter standing stocks, and woody riparian zones. Models contained both reach- and landscape-scale variables. Difference in the extent of agricultural and forest land use/cover between Michigan and Minnesota may explain the differences in the models predicting wood variables. Patterns in wood abundance and distribution in these Midwestern streams differ from those observed in high gradient regions, and in low-gradient streams within forested regions. This has important implications for ecosystem processes and management of headwater streams in agricultural regions.
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"Landscape Influences on Stream Habitats and Biological Assemblages." In Landscape Influences on Stream Habitats and Biological Assemblages, edited by Kelly M. Burnett, Gordon H. Reeves, Sharon E. Clarke, and Kelly R. Christiansen. American Fisheries Society, 2006. http://dx.doi.org/10.47886/9781888569766.ch9.
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<em>Abstract.</em>—Multiscale analysis of relationships with landscape characteristics can help identify areas and physical processes that affect stream habitats, and thus suggest where and how land management is likely to influence these habitats. Such analysis is rare for mountainous areas where forestry is the primary land use. Consequently, we examined relationships in a forested, montane basin between stream habitat features and landscape characteristics that were summarized at five spatial scales (three riparian and two catchment scales). Spatial scales varied in the area encompassed upstream and upslope of surveyed stream segments and, presumably, in physical processes. For many landscape characteristics, riparian spatial scales, approximated by fixed-width buffers, could be differentiated from catchment spatial scales using forest cover from 30-m satellite imagery and 30-m digital elevation data. In regression with landscape characteristics, more variation in the mean maximum depth and volume of pools was explained by catchment area than by any other landscape characteristic summarized at any spatial scale. In contrast, at each spatial scale except the catchment, variation in the mean density of large wood in pools was positively related to percent area in older forests and negatively related to percent area in sedimentary rock types. The regression model containing these two variables had the greatest explanatory power at an intermediate spatial scale. Finer spatial scales may have omitted important source areas and processes for wood delivery, but coarser spatial scales likely incorporated source areas and processes less tightly coupled to large wood dynamics in surveyed stream segments. Our findings indicate that multiscale assessments can identify areas and suggest processes most closely linked to stream habitat and, thus, can aid in designing land management to protect and restore stream ecosystems in forested landscapes.
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"Landscape Influences on Stream Habitats and Biological Assemblages." In Landscape Influences on Stream Habitats and Biological Assemblages, edited by Philip R. Kaufmann, Robert M. Hughes, and Robert M. Hughes. American Fisheries Society, 2006. http://dx.doi.org/10.47886/9781888569766.ch21.
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<em>Abstract.</em>—Physical habitat degradation has been implicated as a major contributor to the historic decline of salmonids in Pacific Northwest streams. Native aquatic vertebrate assemblages in the Oregon and Washington Coast Range consist primarily of coldwater salmonids, cottids, and amphibians. This region has a dynamic natural disturbance regime, in which mass failures, debris torrents, fire, and tree-fall are driven by weather but are subject to human alteration. The major land uses in the region are logging, dairy farming, and roads, but there is disagreement concerning the effects of those activities on habitat and fish assemblages. To evaluate those effects, we examined associations among physical and chemical habitat, land use, geomorphology, and aquatic vertebrate assemblage data from a regional survey. In general, those data showed that most variation in aquatic vertebrate assemblage composition and habitat characteristics is predetermined by drainage area, channel slope, and basin lithology. To reveal anthropogenic influences, we first modeled the dominant geomorphic influences on aquatic biotic assemblages and physical habitat in the region. Once those geomorphic controls were factored out, associations with human activities were clarified. Streambed instability and excess fines were associated with riparian disturbance and road density, as was a vertebrate assemblage index of biotic integrity (IBI). Low stream IBI values, reflecting lower abundances of salmonids and other sediment-intolerant and coldwater fish and amphibian taxa, were associated with excess streambed fines, bed instability, higher water temperature, higher dissolved nutrient concentrations, and lack of deep pools and cover complexity. Anthropogenic effects were more pronounced in streams draining erodible sedimentary bedrock than in those draining more resistant volcanic terrain. Our findings suggest that the condition of fish and amphibian assemblages in Coast Range streams would be improved by reducing watershed activities that exacerbate erosion and mass-wasting of sediment; protecting and restoring multilayered structure and large, old trees in riparian zones; and managing landscapes so that large wood is delivered along with sediment in both natural and anthropogenic mass-wasting events. These three measures are likely to increase relative bed stability and decrease excess fines by decreasing sediment inputs and increasing energy-dissipating roughness from inchannel large wood and deep residual pools. Reducing sediment supply and transport to sustainable rates should also ensure adequate future supplies of sediment. In addition, these measures would provide more shade, bankside cover, pool volume, colder water, and more complex habitat structure.
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Legnani, Nicole D. "Invasive Specie." In Latin American Culture and the Limits of the Human, 127–49. University Press of Florida, 2020. http://dx.doi.org/10.5744/florida/9781683401490.003.0006.
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This chapter traces a narrative archipelago from Madeira to Hispaniola through the metonymy of wood and the trajectory of Christopher Columbus, as allegorized by an anecdote about the reproductive destruction of an invasive species on a deserted island off the coast of West Africa in the Historia de las Indias by Bartolomé de Las Casas. It reflects on the connections afforded by the polysemy of naturaleza in sixteenth-century Spanish and made by Las Casas in his anecdotes about colonial capitalism on Hispaniola and Madeira in both Historia de las Indias and his edition of Christopher Columbus’s Diario a Bordo.As islands have always served as schematic shorthand for categories and indigeneity, an anecdote about a plague of rabbits on the Madeira islands in the early fifteenth century blurs the limits between state and enterprise, animal and human, native and nature (naturaland naturaleza), and the natural and unnatural (naturaand contra natura). What seems like a digression into the Madeira rabbits from Las Casas’s larger narrative about the conquest of America serves instead as a self-reflexive allegory for the paradoxical project of narrating origins in historical processes, especially destructive ones that nonetheless reproduce on a global scale.
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Fant, Clyde E., and Mitchell G. Reddish. "Thyatira." In A Guide to Biblical Sites in Greece and Turkey. Oxford University Press, 2003. http://dx.doi.org/10.1093/oso/9780195139174.003.0048.
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The ancient city of Thyatira, known for being one of the cities named in the book of Revelation, continues today as the modern city of Akhisar. A wealthy commercial city in antiquity, the city today is a modern one with a population of more than 80,000. Agriculture is a large part of the economy of the area, with major crops of olives, olive oil, wheat, cotton, grapes, melons, and raisins. The region is especially famous for its tobacco production. Akhisar is located in western Turkey, approximately 30 miles from the Aegean coast and 50 miles northeast of Izmir on highway 565. Situated on the broad Akhisar Plain, the city was in the northern part of the ancient kingdom of Lydia. Because of its location in the center of the large level plain, the city had few natural defenses. Archaeological evidence demonstrates that a settlement existed here as early as 3000 B.C.E. During the 5th century B.C.E., the Persians gained control of the area, followed by Alexander the Great toward the end of the 4th century. At the beginning of the 3rd century, the Seleucid ruler Seleucus I Nicator refounded the city and apparently settled Macedonian soldiers in the city. Serving as a military outpost, Thyatira became a part of the Pergamene kingdom under the Attalid rulers by 189 B.C.E. (if not earlier). After Attalus III bequeathed his Pergamene kingdom to the Romans in 133 B.C.E., the Romans established the province of Asia in 129 B.C.E., and Thyatira came under Roman rule. Located at the crossroads of the major routes leading northwest to Pergamum, southeast to Sardis, and southwest to Magnesia and Smyrna, Thyatira became an important trade, industrial, and commercial center. Inscriptional evidence indicates that the city was host to numerous trade guilds, which functioned as social, civic, and religious clubs or organizations. Among the guilds represented at Thyatira were the guilds of coppersmiths, tanners, leatherworkers, dyers, wool workers, and linen workers. The wool and textile industries were particularly strong in Thyatira, as was also the production of purple dye. During the Roman era the city prospered. Inscriptions discovered in the city mention the existence of three gymnasiums, a colonnaded portico of one hundred columns, stoas, shops, and shrines to the sun god Apollo Tyrimnaeus and to Artemis Boreitene.
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Paruelo, José María, and Estebán G. Jobbágy. "The Grasslands and Steppes of Patagonia and the Río de la Plata Plains." In The Physical Geography of South America. Oxford University Press, 2007. http://dx.doi.org/10.1093/oso/9780195313413.003.0022.
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The Patagonian steppes and the Río de la Plata grasslands occupy a vast proportion of the plains, plateaus, and hills of southern South America, and are characterized by the almost absolute absence of trees. Prairies and steppes (grass and low shrubs) are the dominant physiognomic types, and forests are restricted to some riparian corridors. Savannas become important only in the ecotones of these regions, whereas meadows may be locally important under particular topographic or edaphic conditions. The Río de la Plata grasslands (RPG), one of the most important grassland regions in the world, extend between 28°S and 38°S latitude, covering about 700,000 km2 of eastern Argentina, Uruguay, and southern Brazil. The boundaries of these grasslands include the Atlantic coastline to the east, dry temperate forests to the south and west, and subtropical humid forests to the north. Woody vegetation within the region is restricted to small areas near water bodies, such as the gallery forests along the large Paraná and Uruguay rivers and their tributary streams. The Patagonian steppes occupy the southern tip of the continent from approximately 40°S, and are framed by the Andes to the west and the Atlantic coast to the east and south and cover more than 800,000 km2 of Chile and Argentina. Toward the west, the region displays a sharp ecotone with the subantarctic forests, whereas to the north it grades into a broad zone of Monte scrublands in central Argentina. The RPG and the Patagonian steppes are separated by a wide strip of woody vegetation, the Monte and Espinal phytogeographic units (see chapter 10; Cabrera and Willkins, 1973). In this chapter, we describe the heterogeneity and main characteristics of the dominant ecosystems of the Patagonian steppes and the RPG, focusing on environmental controls and human-induced changes. Although numerous criteria have been applied to describe the internal heterogeneity of both regions, we emphasize here the structural and functional attributes of vegetation as integrators of climate, physiography, and land use.
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Fant, Clyde E., and Mitchell G. Reddish. "Colossae." In A Guide to Biblical Sites in Greece and Turkey. Oxford University Press, 2003. http://dx.doi.org/10.1093/oso/9780195139174.003.0030.
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At one time a thriving city in the fertile valley of the Lycus River, the city of Colossae is almost forgotten today. If not for its significance to the Bible, the site of ancient Colossae, now only an unexcavated mound, would be visited very seldom. Colossae was situated near the Lycus River (today the Aksu Çay), the chief tributary of the Meander River. Located in the Phrygian region of Asia Minor, the city was approximately 120 miles east of Ephesus. During the 5th and 4th centuries B.C.E. Colossae was a large and prosperous city. At that time the leading city of the Lycus Valley, Colossae was eventually eclipsed in importance during the Hellenistic and Roman periods by the neighboring cities of Laodicea and Hierapolis. The textile industry flourished in the Lycus Valley, particularly because of goods made from the exceptionally fine wool produced in the area. Colossae was well known for its purple-colored wool. The economic prosperity of the city was also due to its being located on the main trade route from the Aegean coast to the Euphrates. Like Laodicea and Hierapolis, Colossae likely was damaged by the severe earthquake that struck the Lycus Valley in 60 C.E. By the 9th century the site was abandoned, its remaining inhabitants having moved to the nearby town of Chonae (modern Honaz). To reach the ruins of ancient Colossae, take highway 320 east from Denizli toward Dinar. Approximately 12 miles from Denizli, turn right onto the road for Honaz. After traveling approximately 4 miles, turn left. The site of ancient Colossae, a low hill in a field, is about 6 miles on the right. The ancient city of Colossae is remembered today primarily because one of the letters in the New Testament is addressed to “the saints and faithful brothers and sisters in Christ in Colossae” (Col 1:2). Aside from this one reference, the city of Colossae does not appear in the New Testament. The Letter to the Colossians claims to be a letter from the Apostle Paul, although its authorship is sometimes attributed to an anonymous disciple of Paul’s who wrote in the name of Paul.
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Papadopoulos, Gerassimos. "Tsunamis." In The Physical Geography of the Mediterranean. Oxford University Press, 2009. http://dx.doi.org/10.1093/oso/9780199268030.003.0031.
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According to Imamura (1937: 123), the term tunami or tsunami is a combination of the Japanese word tu (meaning a port) and nami (a long wave), hence long wave in a harbour. He goes on to say that the meaning might also be defined as a seismic sea-wave since most tsunamis are produced by a sudden dip-slip motion along faults during major earthquakes. Other submarine or coastal phenomena, however, such as volcanic eruptions, landslides, and gas escapes, are also known to cause tsunamis. According to Van Dorn (1968), ‘tsunami’ is the Japanese name for the gravity wave system formed in the sea following any large-scale, short-duration disturbance of the free surface. Tsunamis fall under the general classification of long waves. The length of the waves is of the order of several tens or hundreds of kilometres and tsunamis usually consist of a series of waves that approach the coast with periods ranging from 5 to 90 minutes (Murty 1977). Some commonly used terms that describe tsunami wave propagation and inundation are illustrated in Figure 17.2. Because of the active lithospheric plate convergence, the Mediterranean area is geodynamically characterized by significant volcanism and high seismicity as discussed in Chapters 15 and 16 respectively. Furthermore, coastal and submarine landslides are quite frequent and this is partly in response to the steep terrain of much of the basin (Papadopoulos et al. 2007a). Tsunamis are among the most remarkable phenomena associated with earthquakes, volcanic eruptions, and landslides in the Mediterranean basin. Until recently, however, it was widely believed that tsunamis either did not occur in the Mediterranean Sea, or they were so rare that they did not pose a threat to coastal communities. Catastrophic tsunamis are more frequent on Pacific Ocean coasts where both local and transoceanic tsunamis have been documented (Soloviev 1970). In contrast, large tsunami recurrence in the Mediterranean is of the order of several decades and the memory of tsunamis is short-lived. Most people are only aware of the extreme Late Bronge Age tsunami that has been linked to the powerful eruption of Thera volcano in the south Aegean Sea (Marinatos 1939; Chapter 15).
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Bianchi, Thomas S. "Changes in the Hinterland and Floodplain." In Deltas and Humans. Oxford University Press, 2016. http://dx.doi.org/10.1093/oso/9780199764174.003.0009.
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As human populations have increased on the planet, so have their effects on the natural landscape. When human-engineered changes in the movement of soils and rocks occur in the vast watersheds of major rivers, they can have dramatic consequences with respect to the amount of sediment needed to “feed” and support large river deltas at the coast. Many of the largest effects of human activity on the surface of the earth have occurred recently—in the past 200 or so years—and they have been so dramatic it has been argued it is time to create a new epoch in the Geologic Time Scale, one called the Anthropocene. That suggestion is being considered seriously. Nevertheless, the first alterations of the landscape began as early as the Paleolithic, approximately 400,000 to 500,000 years ago, when our human-like ancestors Homo erectus are believed to have begun altering the natural landscape with simple dwelling structures. As humans evolved, so did the tools they used, from sticks and animal antlers to wood and iron plows. Although modern humans (Homo sapiens sapiens) had developed in East Africa by about 200,000 years ago, their ability to extensively modify the landscape through agricultural activities did not likely happen for another 120,000 years. Incredibly, there was a rise in agricultural communities about five millennia ago that seems to have occurred simultaneously, yet independently, in six different regions of world (see Chapters 1 and 2 for linkages among human civilizations, deltas, and stabilization of climate in the Holocene). After the invention of the wheel in the middle Holocene, it became much easier to perform earth-moving activities. This was followed by the Iron Age, around 2,500 years ago, during which iron replaced earlier, less efficient copper and bronze tools for moving earth. Amazingly, the first man-made canal, connecting the Mediterranean and Red seas, was constructed before the Iron Age, around 3,600 years ago. Today, humans are the most effective animals on the planet with respect to altering Earth’s surface, and the use of machinery enables earth-moving activities, such as strip- mining, for extraction of valuable mineral resources like copper and silver.
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"Fish Habitat: Essential Fish Habitat and Rehabilitation." In Fish Habitat: Essential Fish Habitat and Rehabilitation, edited by Paul A. Heikkila. American Fisheries Society, 1999. http://dx.doi.org/10.47886/9781888569124.ch20.
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<em>Abstract.</em> —The Coquille watershed contains the largest coastal river originating within the Coast Range of Oregon. The Coquille River presently supports over 57 species of fish including coho salmon <em>Oncorhynchus kisutch</em> , spring and fall chinook salmon <em>O. tshawytscha</em> , resident and sea-run cutthroat trout <em>O. clarki</em> , winter steelhead trout <em>O. mykiss</em> , and a remnant population of chum salmon <em>O. keta</em> . Coho salmon have been listed as threatened under the Endangered Species Act. Many factors including habitat alterations, harvests, hatchery introductions, and ocean conditions have led to the decline of many Coquille River fish stocks. Habitat changes since European settlement began in the mid- 1800s include logging and log transport, road building, draining and diking for agriculture, and urbanization, which have all contributed to the decline of fish stocks and water quality within the watershed. The recognition of habitat problems as a key limiting factor for fish production and water quality led to the formation of the Coquille Watershed Association (CWA) in early 1994. The formation of the CWA was another step in a 20-year local effort to address habitat problems through restoration of natural processes. The CWA is organized as a nonprofit corporation and is governed by a 26-member executive council representing landowners and stakeholders within the watershed. The goals of the CWA, which arrives at decisions through consensus, include creating water quality conditions that will meet Clean Water Act standards and enhancing native fish survival and production through public and private partnerships. To reach those goals, the CWA has organized a technical advisory group and developed an Action Plan that address limiting factors and sets priorities for identifying, prioritizing, coordinating, accomplishing, and monitoring restoration projects and educational efforts. To date the CWA has generated over US$2.5 million in public and private funding to implement projects including riparian restoration through fencing and planting, wetland development, the addition of large-channel wood and rock, off-channel livestock watering, and over 40 educational tours.
Conference papers on the topic "Large coarse wood"
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Saasen, Arild, Helge Hodne, Egil Ronæs, Simen André Aarskog, Bente Hetland, Marie Bjørdal Løvereide, and Rahmat Mohammadi. "Wood Fibre Based Lost Circulation Materials." In ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/omae2018-77662.
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In this paper both a coarse and fine wood fibre type of Lost Circulation Material (LCM) is tested in the laboratory. It is shown how these fibre treatments work. The fibre type is partially oil wetting making them suitable for application in oil based drilling fluids. The fine material helps stopping small drilling induced fractures, while the coarse helps stopping lost circulation into several natural fractures or coal or conglomerate formations. In the article, the selection of wood fibres is described in more detail. Testing of the fine materials were conducted conventionally by pumping drilling fluid volumes with LCM onto slotted disks in fluid loss apparatuses. The coarse fibres are too large to be tested in these apparatuses. Therefore, gravel with grain diameter around two centimetres was filled into transparent cylinders. The pore throats created by these gravel particles were above half a centimetre. For both of these LCMs the experiments show the sensitivity of the LCM concentration in the drilling fluid to stop the lost circulation. Also, it is shown the effect of the LCM on viscous properties of the drilling fluids. Not all LCMs can be pumped through the bit. The article describes the need for circulation subs in the bottom hole assembly (BHA) to hinder the LCM blocking the entire BHA.
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Rainio, Aku, Vinod Sharma, Markus Bolha`r-Nordenkampf, Christian Brunner, Johannes Lind, and John Crosher. "Fluidized Bed Technologies for Biomass Combustion." In ASME 2009 Power Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/power2009-81052.
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Biomass, a renewable fuel source for generating energy, is available in large quantities in the USA. Typical biomass consists of wood chips, construction and demolition wood, bark, residual logging debris, saw dust, paper rejects, and paper and sewage sludge. Composition and moisture content of biomass vary greatly and affect its heating value. There are several combustion technologies available to generate power from biomass. Fluidized bed boilers are preferred, because of their ability to burn a wide variety of biomass fuels while achieving high combustion efficiency and low emissions. This paper discusses basic design and operation features of bubbling (BFB) and circulating fluidized bed (CFB) boilers, both offering high fuel flexibility. In fluidized bed combustion, reactive biomass fuels are almost completely burned out because of close contact between the hot bed material and the fuel. In advanced BFB and CFB boilers, an open bottom design is used for ash and coarse material removal through the fluidizing air distribution system. This allows combustion of fuels containing large inert particles, such as rocks and metal pieces. If limestone is added to the bed, SO2 emissions are reduced. By using ammonia or urea in high temperature areas, NOx emissions are reduced. In order to achieve very low emissions, back-end flue gas treatment for SO2, NOx, HCl, HF, and Hg is required. To treat flue gases, several technologies can be used — such as activated carbon and sodium bicarbonate or Trona injection, Turbosorp® circulating dry scrubber, and SCR. Normally the preferred particulate matter cleaning device is a baghouse since the filter cake allows further reactions between pollutants and sorbents. Different fluidized bed designs are shown and recommended for various biomass fuels. This paper describes design, fuels, and emissions for an advanced BFB boiler producing steam at a rate of 230,000 lb/hr/930 psig/860°F (29.0 kg/s/64 barg/460°C).
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Borges, Ianca Oliveira, Maria Clara Rodrigues da Costa, Ana Luiza Alves de Alpoim, and Mauricio Teodoro da Silva. "Feasibility study of the implementation of an evapotranspiration basin with the aid of an ash box as preliminary treatment." In II INTERNATIONAL SEVEN MULTIDISCIPLINARY CONGRESS. Seven Congress, 2023. http://dx.doi.org/10.56238/homeinternationalanais-049.
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Abstract The present work aimed at providing knowledge in new sanitation techniques for rural populations and all those who wish to live in a more sustainable way, developing an adequate treatment for their effluents generated in their daily lives. A large part of the Brazilian population does not have basic sanitation or has inadequate forms, such as septic tanks that contaminate the soil and subsequently the water resources of the entire region, with pathogens. Thinking about this idea, an ecologically sustainable way was developed for the treatment of black waters, the Evapotranspiration Basin (BET) with the innovation of the ash box. The sewage coming from the toilet is directed to the ash box built of waterproofed masonry, where it receives preliminary treatment, a gridded basket inside the box retaining coarse solids. In this same box wood ash is added that acts as a flocculant and PH regulator, optimizing the anaerobic digestion process inside the chamber formed by tires in the Evapotranspiration Basin, an impermeable masonry tank submerged in the soil where bacteria remineralize all organic matter. The water contained in the sewage passes through an ascending granulometric filter until it reaches the roots of the plants, where it goes through a natural process of Evapotranspiration, returning a large part of this purified water to the environment. The objective was to compare the budgets of other works and show the economic viability of a BET with the innovation of the ash box.
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Suo-Anttila, Ahti, K. C. Wagner, and Miles Greiner. "Analysis of Enclosure Fires Using the Isis-3D™ CFD Engineering Analysis Code." In 12th International Conference on Nuclear Engineering. ASMEDC, 2004. http://dx.doi.org/10.1115/icone12-49008.
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The Isis-3D™ computational fluid dynamics (CFD) code is currently under development for the Defense Threat Reduction Agency (DTRA) as a tool for risk assessment and engineering level analysis. It is designed to provide reasonably accurate estimates of the total heat transfer to objects from large fires under a variety of circumstances, predict the medium characteristics such as temperature and species concentration distributions, and use fairly short computer turnaround times. Isis-3D™ models liquid fuel evaporation, transport of fuel vapor, oxygen and other relevant species, reaction and heat release, and soot and other gaseous species formation, destruction, and transport. It models diffuse radiation within the fire and view factor radiation from the fire edge to nearby objects and the surroundings. One-dimensional transient sub-grid modules are also embedded into Isis-3D™. Either or both “ends” of each module are coupled to the flowing medium region, or objects within the three-dimensional medium. These modules allow the code to calculate the one-dimensional response of simple solid objects to the fire environment without affecting the computational fluid dynamics time step. The sub-grid modules can include thermal conduction, convection, momentum, mass, and species exchange. For example, they can be used to simulate the decomposition of organic materials (e.g. burning wood), the evaporation of liquid fuels, and the injection of gases, such as fire suppressants. Fast-running radiation heat transfer and chemical reaction models embedded in the code are designed to enable it to give engineering-level accurate results for large-fire heat transfer even when relatively coarse computational grids are employed. Low to medium level resolution Isis-3D™ simulations (less than 60,000 nodes) are relatively fast running and hence well suited for risk assessments, parametric scenario variations, and engineering level analyses. This paper includes comparisons of Isis-3D™ predictions to two enclosure fire experiments, the classical Steckler room fire experiments and the Sandia National Laboratories (SNL) Igloo enclosure fires. The Steckler fire experiments were steady state fires with a fixed heat input. The SNL Igloo tests were larger scale, unsteady fuel pan fires. Comparisons of the predicted temperature distributions within the enclosures for several tests are shown. A typical application of Isis-3D™ is also illustrated wherein the CO2 fire suppressant distribution within the cable room of a nuclear power plant is predicted as a function of time.
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Almazan, J., D. Fernandez, A. Fornes, Josep Llados, and E. Valveny. "A Coarse-to-Fine Approach for Handwritten Word Spotting in Large Scale Historical Documents Collection." In 2012 International Conference on Frontiers in Handwriting Recognition (ICFHR). IEEE, 2012. http://dx.doi.org/10.1109/icfhr.2012.151.
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Green, Alex E. S., and Ritesh P. Chaube. "Pyrolysis Systematics for Co-Utilization Applications." In ASME Turbo Expo 2003, collocated with the 2003 International Joint Power Generation Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/gt2003-38229.
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A semi-empirical model (SEM) of slow pyrolysis (SP) of carbonaceous material along nature’s coalification path has been under development to facilitate blending of various feedstocks in fuel conversion systems (pyrolyzers, combustors, gasifiers, liquefiers and carbonizers). The model was adjusted to coal data in the literature and our own drop tube pyrolysis measurements with various types of biomass. The latest version of the model is here adapted to represent the flash pyrolysis (FP) yields of 15 products (CaHbOc) for 17 coal types measured by Xu and Tomita (XT) at 1037°K and at 5 additional temperatures for 8 of the coals. A good analytical representation of yields vs. C, H and O wt%s and temperature is found that makes the Xu-Tomita FP measurements conveniently available for many fuel conversion applications. Our larger objective is to help bring order into the fundamentals underlying humankind’s oldest technologies, the extraction of energy out of wood and coal.
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Franzoni, A., L. Galanti, A. Traverso, and A. F. Massardo. "Thermoeconomic Analysis of Integrated Systems for Electricity and Hydrogen Production." In ASME 2008 Power Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/power2008-60115.
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This paper describes and compares the results of thermodynamic and economic modelling based on integrating an existing large size steam power plant (ENEL’s Brindisi power plant-660 MWe) with hydrogen production and purification plants. ENEL is one of the main Italian power utility. The high quality of the hydrogen produced would guarantee its usability for distributed generation (e.g. by micro gas turbine, Stirling engine, fuel cell, etc.) and also for public transport (using PEM fuel cells). The proximity of an hydrogen production and purification plant to an existing steam power plant can favour connections in terms of energy requirements exchanges; the integrated system, proposed here, can represent an attractive approach to a flexible hydrogen-electricity co-production. Two different technologies for the syngas production section are considered: the pyrolysis process and direct pressurised gasification. These technologies produce syngas with different characteristics in terms of temperature, pressure and composition: this has a profound effect on the layout of the complete systems proposed in this paper. The model for the pyrolysis process is based on an existing 800 kWt coal- and biomass-fed pyrolysis ENEL’s plant placed in Bastardo (Perugia, Italy): a detailed model of the plant was created. Different coals (Ashland, South Africa, Sulcis) and biomass (Poplar, Mischantus, Wood residuals, Husk) are considered in this study to explore the real potential of mixed-fuels in terms of thermodynamic performances and costs. The results were obtained using WTEMP software, developed by the TPG of the University of Genoa, showing the performance attainable by integrating a real steam power plant with systems for hydrogen production and purification for a novel vision of clean distributed hydrogen generation.
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Kokko, Ari, and Stig Nickull. "The First Operational Experience of World’s Largest Biofuel Fired CFB." In 17th International Conference on Fluidized Bed Combustion. ASMEDC, 2003. http://dx.doi.org/10.1115/fbc2003-034.
Full textAbstract:
Oy Alholmens Kraft Ab, with its unique combination of owners, was founded for the purpose of building a power station at Pietarsaari on the west coast of Finland. The power utility companies initiated the co-operation with the saw-, pulp and paper mill owners with the goal of finding a solution which maximized biomass utilization through co-firing with other fuels, to produce steam and heat in a utility sized power plant. Concept development resulted in a 240 MWe circulating fluidized bed unit with a flexible and demanding combination of fuels. The Alholmens Kraft power plant supplies process steam to the nearby UPM-Kymmene paper mill, and for district heating in Pietarsaari. The plant produces electricity for the power company owners in Finland and in Sweden. The CFB boiler steam capacity is 550 MWth (1875 MMBtu/hr), giving a maximum electric power of 240 MWe. When commissioned in autumn 2001 the boiler was one of the largest CFB boilers in the world, and the largest biofuel-burning CFB. The Alholmens Kraft CFB boiler is a multi-fuel boiler, whose main fuels are bark, wood residue and peat, with coal as a back-up fuel. Due to its location at the pulp and paper mill, high reliability and low emissions were the most important design criteria for the boiler. Steam production for the mill must be ensured all year-round, apart from during the mill’s short annual service shutdowns. Another important design consideration was the controllability of the boiler due to Nord Pool electricity production requirements. Typical regular load variation is between day and night but sometimes the load change speed requirement is quite high. This paper presents the Alholmens Kraft power plant application, and its very smooth start-up and operational experience during the first year with different fuels and fuel combinations at various load levels. The paper also describes how well the large boiler has performed with regard to the strict emission limits. The selection of design fuel contributes well towards the target for net CO2 reduction, but it also places huge requirements in terms of fuel purchasing and logistics. The volumetric fuel consumption by the boiler at full load is 1000 m3/h (35 000 ft3) of biofuel. More coal, the support and reserve fuel, is used in spring as weather conditions may cause availability problems with peat, before the new peat can be harvested and dried at the peat bogs. Coal is always available at the site. This paper presents the first year’s operational experience of the fuel logistics chain. The successful Alholmens Kraft CFB boiler project is an excellent example of the very wide fuel flexibility that is possible in a CFB unit.
Reports on the topic "Large coarse wood"
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McCay Timothy, S., James, L. Hanula, Susan, C. Loeb, Steven, M. Lohr, James, W. McMinn, and D. Wright-Miley. Bret. The role of coarse woody debris in southeastern pine forests; preliminary results from a large-scale experiment. Office of Scientific and Technical Information (OSTI), August 2002. http://dx.doi.org/10.2172/835556.
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Boyle, Maxwell, and Elizabeth Rico. Terrestrial vegetation monitoring at Timucuan Ecological and Historic Preserve: 2019 data summary—Version 2.0. National Park Service, February 2022. http://dx.doi.org/10.36967/nrds-2290196.
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The Southeast Coast Network (SECN) conducts long-term terrestrial vegetation monitoring as part of the nationwide Inventory and Monitoring Program of the National Park Service (NPS). The vegetation community vital sign is one of the primary-tier resources identified by SECN park managers, and it is currently conducted on 15 network parks (DeVivo et al. 2008). Monitoring plants and their associated communities over time allows for targeted understanding of ecosystems within the SECN geography, which provides managers information about the degree of change within their parks’ natural vegetation. 2019 marks the first year of conducting this monitoring effort on four SECN parks, including Timucuan Ecological and Historic Preserve (TIMU). A total of 23 vegetation plots were established in the park in May and June. Data collected in each plot include species richness across multiple spatial scales, species-specific cover and constancy, species-specific woody stem seedling/sapling counts and adult tree (greater than 10 centimeters [3.9 inches (in)]) diameter at breast height (DBH), overall tree health, landform, soil, observed disturbance, and woody biomass (i.e., fuel load) estimates. This report summarizes the baseline (year 1) terrestrial vegetation data collected at Timucuan Ecological and Historic Preserve in 2019. Data were stratified across three dominant broadly defined habitats within the park (Coastal Plain Nonalluvial Wetlands, Coastal Plain Open Uplands and Woodlands, and Maritime Upland Forests and Shrublands) and three land parcels (Cedar Point, Theodore Roosevelt, and Thomas Creek). Noteworthy findings include: A total of 157 vascular plant taxa (species or lower) were observed across 23 vegetation plots, including nine species not previously known from the park. Three plots were located in the footprint of the Yellow Bluff Fire, and were sampled only two weeks following the fire event. Muscadine (Muscadinia rotundifolia), cat greenbrier (Smilax glauca), water oak (Quercus nigra), and swamp tupelo (Nyssa biflora) were the most frequently encountered species in Coastal Plain Nonalluvial Wetland habitat; saw palmetto (Serenoa repens), slash pine (Pinus elliottii), and gallberry (Ilex glabra) were the most frequently encountered species in Coastal Plain Open Upland and Woodland habitat; and Darlington oak (Quercus hemisphaerica), Spanish moss (Tillandsia usenoides), and red bay (Persea borbonia) were the most frequently encountered species in Maritime Upland Forests and Shrublands. There were no exotic species of the Florida Exotic Pest Plant Council list of invasive plants (FLEPPC 2020) observed on any of these plots. Both red bay and swamp bay (Persea palustris) were largely absent from the tree stratum in these plots; however, they were present (occasionally in high abundance) in the seedling and sapling strata across all habitat types. Buckthorn bully (Sideroxylon lycioides)—listed as Endangered in the state of Florida by the Florida Department of Agriculture and Consumer Services (FDACS 2020)—was observed in three Maritime Upland Forest and Shrubland plots. The tree strata in each broadly defined habitat were dominated by the following species: Coastal Plain Nonalluvial Wetlands-loblolly bay (Gordonia lasianthus) Coastal Plain Open Uplands and Woodlands-longleaf pine (Pinus palustris) Maritime Upland Forests and Shrublands-oaks (Quercus sp.) Most stems within the tree strata exhibited healthy vigor and only moderate dieback across all habitat types. However, there was a large amount of standing dead trees in plots within Maritime Upland Forests and Shrublands. Downed woody biomass (fuel loads) were highest in the Cedar Point and Thomas Creek land parcels.
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Cooper, Christopher, Jacob McDonald, and Eric Starkey. Wadeable stream habitat monitoring at Congaree National Park: 2018 baseline report. National Park Service, June 2021. http://dx.doi.org/10.36967/nrr-2286621.
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The Southeast Coast Network (SECN) Wadeable Stream Habitat Monitoring Protocol collects data to give park resource managers insight into the status of and trends in stream and near-channel habitat conditions (McDonald et al. 2018a). Wadeable stream monitoring is currently implemented at the five SECN inland parks with wadeable streams. These parks include Horseshoe Bend National Military Park (HOBE), Kennesaw Mountain National Battlefield Park (KEMO), Ocmulgee Mounds National Historical Park (OCMU), Chattahoochee River National Recreation Area (CHAT), and Congaree National Park (CONG). Streams at Congaree National Park chosen for monitoring were specifically targeted for management interest (e.g., upstream development and land use change, visitor use of streams as canoe trails, and potential social walking trail erosion) or to provide a context for similar-sized stream(s) within the park or network (McDonald and Starkey 2018a). The objectives of the SECN wadeable stream habitat monitoring protocol are to: Determine status of upstream watershed characteristics (basin morphology) and trends in land cover that may affect stream habitat, Determine the status of and trends in benthic and near-channel habitat in selected wadeable stream reaches (e.g., bed sediment, geomorphic channel units, and large woody debris), Determine the status of and trends in cross-sectional morphology, longitudinal gradient, and sinuosity of selected wadeable stream reaches. Between June 11 and 14, 2018, data were collected at Congaree National Park to characterize the in-stream and near-channel habitat within stream reaches on Cedar Creek (CONG001, CONG002, and CONG003) and McKenzie Creek (CONG004). These data, along with the analysis of remotely sensed geographic information system (GIS) data, are presented in this report to describe and compare the watershed-, reach-, and transect-scale characteristics of these four stream reaches to each other and to selected similar-sized stream reaches at Ocmulgee Mounds National Historical Park, Kennesaw Mountain National Battlefield Park, and Chattahoochee National Recreation Area. Surveyed stream reaches at Congaree NP were compared to those previously surveyed in other parks in order to provide regional context and aid in interpretation of results. edar Creek’s watershed (CONG001, CONG002, and CONG003) drains nearly 200 square kilometers (77.22 square miles [mi2]) of the Congaree River Valley Terrace complex and upper Coastal Plain to the north of the park (Shelley 2007a, 2007b). Cedar Creek’s watershed has low slope and is covered mainly by forests and grasslands. Cedar Creek is designated an “Outstanding Resource Water” by the state of South Carolina (S.C. Code Regs. 61–68 [2014] and S.C. Code Regs. 61–69 [2012]) from the boundary of the park downstream to Wise Lake. Cedar Creek ‘upstream’ (CONG001) is located just downstream (south) of the park’s Bannister Bridge canoe landing, which is located off Old Bluff Road and south of the confluence with Meyers Creek. Cedar Creek ‘middle’ and Cedar Creek ‘downstream’ (CONG002 and CONG003, respectively) are located downstream of Cedar Creek ‘upstream’ where Cedar Creek flows into the relatively flat backswamp of the Congaree River flood plain. Based on the geomorphic and land cover characteristics of the watershed, monitored reaches on Cedar Creek are likely to flood often and drain slowly. Flooding is more likely at Cedar Creek ‘middle’ and Cedar Creek ‘downstream’ than at Cedar Creek ‘upstream.’ This is due to the higher (relative to CONG001) connectivity between the channels of the lower reaches and their out-of-channel areas. Based on bed sediment characteristics, the heterogeneity of geomorphic channel units (GCUs) within each reach, and the abundance of large woody debris (LWD), in-stream habitat within each of the surveyed reaches on Cedar Creek (CONG001–003) was classified as ‘fair to good.’ Although, there is extensive evidence of animal activity...
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Rine, Kristin, Roger Christopherson, and Jason Ransom. Harlequin duck (Histrionicus histrionicus) occurrence and habitat selection in North Cascades National Park Service Complex, Washington. National Park Service, April 2022. http://dx.doi.org/10.36967/nrr-2293127.
Full textAbstract:
Harlequin ducks (Histrionicus histrionicus) are sea ducks that migrate inland each spring to nest along fast-flowing mountain streams. They are considered one of the most imperiled duck species in North America and occur in two distinct populations on the Atlantic and Pacific coasts. The Pacific coast population includes Washington State, where harlequin ducks breed in the Olympic, Cascade, and Selkirk Mountains. This species is designated as a Management Priority Species by the National Park Service within North Cascades National Park Service Complex (NOCA). This report summarizes harlequin duck surveys conducted during 15 years across a 27-year period (1990 and 2017) on major streams within NOCA, and incidental observations collected from 1968–2021. The primary objectives of these surveys were to 1) document the distribution and abundance of harlequin duck observations within NOCA boundaries, 2) describe productivity (number of broods and brood size), 3) describe breeding chronology of harlequin ducks, and 4) describe habitat characteristics of breeding streams. Sixty-eight stream surveys over 15 years resulted in observations of 623 individual harlequin ducks comprising various demographics, including single adults, pairs, and broods. In addition, we collected 184 incidental observations of harlequin ducks from visitors and staff between 1968–2021. Harlequin ducks were observed on 22 separate second- to sixth-order streams throughout NOCA across the entire 53-year span of data, both incidentally and during harlequin duck surveys by Park staff. Harlequin ducks were detected on 8 of the 13 streams that were actively surveyed. Excluding recounts, 88.7% (n = 330) of individual harlequin duck observations during surveys occurred in the Stehekin River drainage. Between all surveys and incidental observations, 135 unpaired females without broods were sighted across all NOCA waterways. Thirty-nine broods were recorded between NOCA surveys and incidental observations, with a mean brood size of 3.61 (± 1.44 SD; range = 2–10). Breeding pairs were recorded as early as April 5 and were seen on streams until June 15, a period of less than seven weeks (median: May 2), but most pairs were observed within a 3-week span, between April 26 and May 17. Single females (unpaired with a male, with (an)other female(s), or with a brood) were observed on streams between April 26 and August 25 (median: July 3), though most observations were made within a 5-week period between June 12 and July 19. Habitat data collected at adult harlequin duck observation sites indicate that the birds often used stream reaches with features that are characteristic of high-energy running water. While adults occupied all instream habitat types identified, non-braided rapids and riffles were used most frequently, followed by pools and backwaters. Larger instream substrate sizes (cobbles and boulders) were present at most observation sites. Adult harlequin ducks were more often found at locations that lacked visible drifting or lodged woody debris, but drift debris was a slightly more abundant debris type. The presence of gravel bars and at least one loafing site was common. Adult harlequin ducks were more often observed in association with vegetation that offered some cover over the channel, but not where banks were undercut. The average channel width at adult observation sites was 34.0 m (range: 6-80 m; n = 114) and 27.6 m (± 15.7 m; range: 10-60 m; n = 12) at brood observation sites. Compared to adult harlequin duck sites, broods were observed more frequently in low velocity habitat (pools, backwaters), but rarely in rapids. Cobble and boulder substrates were still the most dominant substrate type. Contrary to adult ducks, broods were observed most often observed in meandering stream channels, a morphology indicative of low gradient, low velocity stream reaches. Most broods were observed in stream reaches with gravel bars, loafing sites, and...