scholarly journals A Disturbance Ecology Perspective on Silvicultural Site Preparation

Forests ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1278
Author(s):  
Jéssica Chaves Cardoso ◽  
Philip J. Burton ◽  
Che M. Elkin
Keyword(s):  
Site Preparation ◽  
Disturbance Ecology ◽  
Tree Regeneration ◽  
Numerical Estimation ◽  
Managed Forests ◽  
Ecological Disturbance ◽  
Preparation Methods ◽  
Herbicide Use ◽  
Preparation Techniques ◽  
Quantitative Assessments

Silvicultural site preparation methods are used as planned disturbances for counteracting soil and vegetation constraints, as well as facilitating successful tree regeneration and growth. Understanding the possible effects of silvicultural site preparation on the ecosystem and evaluating site preparation as an ecological disturbance can help guide the selection and application of site preparation techniques for forest management goals. This review evaluates silvicultural site preparation techniques that are commonly used in boreal mixedwood ecosystems as agents of ecological disturbance by comparing the effects of each technique on the area disturbed and the degree of biomass modification, and then ordering them along a disturbance severity gradient. With a strong emphasis on the numerical estimation of the spatial footprint of different disturbances, broadcast burning typically has the highest disturbance severity, followed in order by broadcast herbicide use, mixing, plowing, disc trenching, mounding, scalping, and inverting. The evaluation of disturbance severity of various silvicultural site preparation techniques while using the proposed framework is feasible, in which quantitative assessments of area disturbed and biomass modification could be collected and assessed in most managed forests.

scholarly journals Four Site-Preparation Techniques for Regenerating Pine-Hardwood Mixtures in the Piedmont

1997 ◽  
Vol 21 (3) ◽  
pp. 116-122 ◽  
Author(s):  
Thomas A. Waldrop
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Height Growth ◽  
Site Preparation ◽  
Site Conditions ◽  
Growing Seasons ◽  
Southern Appalachian ◽  
Medium Quality ◽  
Pinus Taeda L ◽  
Preparation Techniques

Abstract Four variations of the fell-and-burn technique, a system developed to produce mixed pine-hardwood stands in the Southern Appalachian Mountains, were compared in the Piedmont region. All variations of this technique successfully improved the commercial value of low-quality hardwood stands by introducing a pine component. After six growing seasons, loblolly pine (Pinus taeda L.) occupied the dominant crown position and oaks the codominant position in fell-and-burn treated stands on poor to medium quality sites. The precise timing of felling residual stems, as prescribed by the fell-and-burn technique, may be flexible because winter and spring felling produced similar results. Although summer site preparation burns reduced hardwood height growth by reducing the length of the first growing season, they did not improve pine survival or growth. Pines were as tall as hardwoods within four growing seasons in burned plots and within six growing seasons in unburned plots. Additional research is needed to determine the level or intensity of site preparation needed to establish pine-hardwood mixtures over a range of site conditions. South. J. Appl. For. 21(3):116-122.

scholarly journals A Comparative Analysis of the Piezoelectric Ultrasonic Appliance and Trephine Bur for Apical Location: An In Vitro Study

2021 ◽  
Vol 11 (10) ◽  
pp. 1034
Author(s):  
Esther Cáceres Madroño ◽  
Paulina Rodríguez Torres ◽  
Soraya Oussama ◽  
Álvaro Zubizarreta-Macho ◽  
María Bufalá Pérez ◽  
...  
Keyword(s):  
Study Groups ◽  
Experimental Models ◽  
Site Preparation ◽  
T Test ◽  
Entry Point ◽  
Osteotomy Site ◽  
End Point ◽  
Planning Software ◽  
Preparation Techniques

To compare and contrast the accuracy of piezoelectric ultrasonic insert (PUI) and trephine bur (TB) osteotomy site preparation techniques for apical location. (1) Material and methods: A total of 138 osteotomy site preparations were randomly distributed into one of two study groups. Group A: TB technique (n = 69) and B: PUI technique (n = 69). A preoperative cone-beam computed tomography scan and an intraoral scan were performed and uploaded to implant-planning software to plan the virtual osteotomy site preparations for apical location. Subsequently, the osteotomy site preparations were performed in the experimental models with both osteotomy site preparation techniques and a postoperative CBCT scan was performed and uploaded into the implant-planning software and matched with the virtually planned osteotomy site preparations to measure the deviation angle and horizontal deviation as captured at the coronal entry point and apical end-point between osteotomy site preparations using Student’s t-test statistical analysis. (2) Results: The paired t-test found statistically significant differences at the coronal entry-point deviations (p = 0.0104) and apical end-point deviations (p = 0.0104) between the TB and PUI study groups; however, no statistically significant differences were found in the angular deviations (p = 0.309) between the trephine bur and piezoelectric ultrasonic insert study groups. (3) Conclusions: The results showed that the TB is more accurate than the PUI for apical location.

scholarly journals Four-year-performance of oak and pine seedlings following mechanical site preparation with lightweight excavators

Silva Fennica ◽  
2021 ◽  
Vol 55 (2) ◽  
Author(s):  
Noé Dumas ◽  
Mathieu Dassot ◽  
Jonathan Pitaud ◽  
Jérôme Piat ◽  
Lucie Arnaudet ◽  
...  
Keyword(s):  
Vegetation Cover ◽  
Untreated Control ◽  
Seedling Survival ◽  
Pinus Nigra ◽  
Quercus Petraea ◽  
Site Preparation ◽  
Pteridium Aquilinum ◽  
Preparation Methods ◽  
Basal Diameter ◽  
Mechanical Site Preparation

Mechanical site preparation methods that used tools mounted on lightweight excavators and that provided localised intensive preparation were tested in eight experimental sites across France where the vegetation was dominated either by (L.) Moench or (L.) Kuhn. Two lightweight tools (Deep Scarifier: DS; Deep Scarifier followed by Multifunction Subsoiler: DS+MS) were tested in pine ( L., var. (Loudon) Hyl. or Aiton) and oak ( (Matt.) Liebl. or  L.) plantations. Regional methods commonly used locally (herbicide, disk harrow, mouldboard plow) and experimental methods (repeated herbicide application; untreated control) were used as references in the experiments. Neighbouring vegetation cover, seedling survival, height and basal diameter were assessed over three to five years after plantation. For pines growing in , seedling diameter after four years was 37% and 98% greater in DS and DS+MS, respectively, than in the untreated control. For pines growing in , it was 62% and 107% greater in the same treatments. For oak, diameter was only 4% and 15% greater in , and 13% and 25% greater in , in the same treatments. For pines, the survival rate after four years was 26% and 32% higher in and 64% and 70% higher in , in the same treatments. For oak, it was 3% and 29% higher in and 37% and 31% higher in . Herbicide, when applied for three or four years after planting, provided the best growth performances for pines growing in and and for oaks growing in . For these species and site combinations, DS+MS and DS treatments reduced the neighbouring vegetation cover for one to four years following site preparation.Molinia caeruleaPteridium aquilinumPinus sylvestrisPinus nigracorsicanaPinus pinasterQuercus petraeaQuercus roburM. caeruleaP. aquilinumM. caeruleaP. aquilinumM. caeruleaP. aquilinumM. caeruleaP. aquilinumM. caerulea P. aquilinumP. aquilinum

Effect of soil physical properties on the long-term performance of planted Scots pine in Finnish Lapland

2010 ◽  
Vol 90 (3) ◽  
pp. 451-465 ◽  
Author(s):  
K. Mäkitalo ◽  
V. Alenius ◽  
J. Heiskanen ◽  
K. Mikkola
Keyword(s):  
Physical Properties ◽  
Water Content ◽  
Scots Pine ◽  
Soil Physical Properties ◽  
Height Growth ◽  
Site Preparation ◽  
Preparation Methods ◽  
Finnish Lapland

Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies L. Karst.) forests dominate in Finnish Lapland. This study examined the long-term effects of soil physical properties and conditions measured in intact intermediate areas, as well as site preparation, on the survival and height growth of planted pine on eight experimental sites, 25-27 yr after reforestation. On the four originally spruce-dominated sites, pine survival was the highest on sites with a high soil air-filled porosity (AFP) near saturation (at -1 kPa), a high van Genuchten parameter, and a low soil water content (SWC) in situ, and height growth was the fastest on sites with a high soil AFP in situ and a high van Genuchten parameter n, and on sites reaching a soil AFP of ca. 0.20 m3 m-3 at a high matric potential after saturation. Survival, but not mean height, was enhanced on the spruce sites by intensive site preparation methods such as ploughing instead of lighter site preparation methods. On the four originally pine-dominated sites, site preparation affected the mean height but not survival. The use of SWC as a sole criterion for sites suitable for pine reforestation was tested and found to be uncertain. Key words: Boreal forest soils, soil water content, air-filled porosity, van Genuchten function, site preparation, reforestation, Scots pine

scholarly journals Comparison of Otolith Readability and Reproducibility of Counts of Translucent Zones Using Different Otolith Preparation Methods for Four Endemic Labeobarbus Species in Lake Tana, Ethiopia

Water ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1336 ◽  
Author(s):  
Gebremedhin ◽  
Bekaert ◽  
Getahun ◽  
Bruneel ◽  
Anteneh ◽  
...  
Keyword(s):  
Management Strategies ◽  
Tropical Fish ◽  
Percentage Error ◽  
Systematic Bias ◽  
Preparation Technique ◽  
Lake Tana ◽  
Preparation Methods ◽  
Average Percentage ◽  
Average Percentage Error ◽  
Preparation Techniques

The analysis of fish age data is vital for the successful conservation of fish. Attempts to develop optimal management strategies for effective conservation of the endemic Labeobarbus species are strongly affected by the lack of accurate age estimates. Although methodological studies are key to acquiring a good insight into the age of fishes, up to now, there have not been any studies comparing different methods for these species. Thus, this study aimed at determining the best method for the endemic Labeobarbus species. Samples were collected from May 2016 to April 2017. Asteriscus otoliths from 150 specimens each of L. intermedius, L. tsanensis, L. platydorsus, and L. megastoma were examined. Six methods were evaluated; however, only three methods resulted in readable images. The procedure in which whole otoliths were first submerged in water, and subsequently placed in glycerol to take the image (MO1), was generally best. Except for L. megastoma, this method produced the clearest image as both the coefficient of variation and average percentage error between readers were lowest. Furthermore, except for L. megastoma, MO1 had high otolith readability and no systematic bias. Therefore, we suggest that MO1 should be used as the standard otolith preparation technique for the first three species, while for L. megastoma, other preparation techniques should be evaluated. This study provides a reference for researchers from Africa, particularly Ethiopia, to develop a suitable otolith preparation method for the different tropical fish species.

scholarly journals Caribou Conservation: Restoring Trees on Seismic Lines in Alberta, Canada

Forests ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 185 ◽  
Author(s):  
Angelo Filicetti ◽  
Michael Cody ◽  
Scott Nielsen
Keyword(s):  
Boreal Forest ◽  
Rangifer Tarandus ◽  
Site Preparation ◽  
Tree Regeneration ◽  
Tree Density ◽  
Petroleum Exploration ◽  
Rangifer Tarandus Caribou ◽  
Mechanical Site Preparation ◽  
Undisturbed Forest ◽  
Seismic Lines

Seismic lines are narrow linear (~3–8 m wide) forest clearings that are used for petroleum exploration in Alberta’s boreal forest. Many seismic lines have experienced poor tree regeneration since initial disturbance, with most failures occurring in treed peatlands that are used by the threatened woodland caribou (Rangifer tarandus caribou). Extensive networks of seismic lines, which often reach densities of 40 km/km2, are thought to have contributed to declines in caribou. The reforestation of seismic lines is therefore a focus of conservation. Methods to reforest seismic lines are expensive (averaging $12,500 per km) with uncertainty of which seismic lines need which treatments, if any, resulting in inefficiencies in restoration actions. Here, we monitored the effectiveness of treatments on seismic lines as compared to untreated seismic lines and adjacent undisturbed reference stands for treed peatlands in northeast Alberta, Canada. Mechanical site preparation (mounding and ripping) increased tree density when compared to untreated lines, despite averaging 3.8-years since treatment (vs. 22 years since disturbance for untreated). Specifically, treated lines had, on average, 12,290 regenerating tree stems/ha, which is 1.6-times more than untreated lines (7680 stems/ha) and 1.5-times more than the adjacent undisturbed forest (8240 stems/ha). Using only mechanical site preparation, treated seismic lines consistently have more regenerating trees across all four ecosites, although the higher amounts of stems that were observed on treated poor fens are not significant when compared to untreated or adjacent undisturbed reference stands.

scholarly journals Practice Patterns in Urinary Cytopathology Prior to the Paris System for Reporting Urinary Cytology

2019 ◽  
Vol 144 (2) ◽  
pp. 172-176 ◽  
Author(s):  
Güliz A. Barkan ◽  
Z. Laura Tabatabai ◽  
Daniel F. I. Kurtycz ◽  
Vijayalakshmi Padmanabhan ◽  
Rhona J. Souers ◽  
...  
Keyword(s):  
Urinary Tract ◽  
Practice Patterns ◽  
Low Frequency ◽  
Daily Practice ◽  
Relevant Information ◽  
Urinary Cytology ◽  
Preparation Methods ◽  
A Cell ◽  
Preparation Techniques ◽  
Urine Specimens

Context.— The Paris System for Reporting Urinary Cytology has been disseminated since its inception in 2013; however, the daily practice patterns of urinary tract cytopathology are not well known. Objective.— To assess urinary tract cytopathology practice patterns across a variety of pathology laboratories to aid in the implementation and future update of the Paris System for Reporting Urinary Cytology. Design.— A questionnaire was designed to gather information about urinary tract cytopathology practices and mailed in July 2014 to 2116 laboratories participating in the College of American Pathologists interlaboratory comparison program. The participating laboratories' answers were summarized. Results.— Of the 879 of 2116 laboratories (41%) that participated, 745 (84.8%) reported processing urinary tract specimens in house. The laboratories reported processing various specimen types: voided urine, 735 of 738 (99.6%); bladder washing/barbotage, 639 of 738 (86.6%); and catheterized urine specimens, 653 of 738 (88.5%). Some laboratories used multiple preparation methods, but the most commonly used preparation techniques for urinary tract specimens were ThinPrep (57.4%) and Cytospin (45.5%). Eighty-eight of 197 laboratories (44.7%) reported preparing a cell block, but with a low frequency. Adequacy criteria were used by 295 of 707 laboratories (41.7%) for voided urine, and 244 of 707 (34.5%) assessed adequacy for bladder washing/barbotage. More than 95% of the laboratories reported the use of general categories: negative, atypical, suspicious, and positive. Polyomavirus was classified as negative in 408 of 642 laboratories (63.6%) and atypical in 189 of 642 (29.4%). One hundred twenty-eight of 708 laboratories (18.1%) performed ancillary testing, and of these, 102 of 122 (83.6%) reported performing UroVysion. Conclusions.— Most laboratories use the ThinPrep method followed by the Cytospin technique; therefore, the criteria published in The Paris System for Reporting Urinary Cytology, based mostly on ThinPrep and SurePath, should be validated for Cytospin, and relevant information should be included in the revised edition of The Paris System for Reporting Urinary Cytology.

scholarly journals Effects of Site Preparation Methods on the Establishment and Natural-Regeneration Traits of Scots Pines (Pinus sylvestris L.) in Northeastern Poland

Forests ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 717 ◽  
Author(s):  
Marta Aleksandrowicz-Trzcińska ◽  
Stanisław Drozdowski ◽  
Marcin Studnicki ◽  
Henryk Żybura
Keyword(s):  
Bulk Density ◽  
Natural Regeneration ◽  
Base Cations ◽  
Nutrient Status ◽  
Site Preparation ◽  
Preparation Methods ◽  
Mechanical Site Preparation ◽  
High Precipitation ◽  
Aridity Indices ◽  
Moisture Conditions

While some tree species can regenerate naturally without mechanical site preparation (MSP), Scots pine has been shown to benefit from this process. We compared three methods: using a double-mouldboard forest plough (FP), an active single-disc plough (AP), and a forest mill (FM), as well as a no-MSP control, in terms of growth, survival and density of occurrence of pines during the first 4 years of natural regeneration. Moisture conditions were expressed via calculated de Martonne aridity indices, while the microhabitats generated via different MSP methods were further characterised by the total contents of N and C, and the C/N ratio, P2O5, and base cations, as well as bulk density and actual moisture. The trials showed inferior regeneration without MSP in terms of the density and cover of young pines. Any of the studied treatments influenced survival, though the best growth was achieved by seedlings using the FP and AP methods, while the best density and evenness results were obtained using AP. The factors most influencing regeneration features were high precipitation during the first growing season after sowing and reduced competition with other vegetation in the cleared area. This impact seems far more important than the capacity of different MSPs to produce differentiation in soil microhabitats in terms of nutrient status or bulk density.

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