scholarly journals Mechanical site preparation: Key to microsite creation success on Clay Belt paludified sites

2015 ◽  
Vol 91 (02) ◽  
pp. 187-196 ◽  
Author(s):  
Mohammed Henneb ◽  
Osvaldo Valeria ◽  
Nicole J. Fenton ◽  
Nelson Thiffault ◽  
Yves Bergeron
Keyword(s):  
Organic Matter ◽  
High Water ◽  
Site Preparation ◽  
Tree Regeneration ◽  
High Water Content ◽  
Organic Layer ◽  
Forest Sector ◽  
Mechanical Site Preparation ◽  
Rooting Zone ◽  
Before And After

Paludification is the accumulation of partially decomposed organic matter over saturated mineral soils. It reduces tree regeneration and growth, mainly because of low temperatures and high water content in the rooting zone, reduced organic matter decomposition, and hence, low nutrient availability. On the Clay Belt of western Québec and eastern Ontario, forests tend to paludify naturally but this process might be promoted by logging methods. Our objective was to identify which of two commonly used mechanical site preparation (MSP) techniques is best adapted to reduce organic layer thickness (OLT) and generate favourable planting microsites post-harvest in paludified sites. Nine experimental blocks (between 20 ha–61 ha each) were delimited within a 35 km2 forest sector with variable levels of paludification. The forest sector was harvested by careful logging to protect advance growth and soils and subsequently the nine experimental blocks were treated with either forest harrowing, disc trenching (T26) or left as untreated controls (harvesting only) with three replicate blocks per treatment. We measured OLT before and after MSP and determined planting microsite quality within each block. Results revealed significant differences in OLT between MSP treatments and harvesting only. Overall, harrowing was the best technique, as it reduced OLT more than T26 scarification and generated the highest percent of good microsites, except where initial OLT was 44 cm–56 cm. Our results contribute to the successful use of MSP in paludified forests.

scholarly journals Effects of Mechanical Site Preparation on Microsite Availability and Growth of Planted Black Spruce in Canadian Paludified Forests

Forests ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 670 ◽  
Author(s):  
Mohammed Henneb ◽  
Osvaldo Valeria ◽  
Nelson Thiffault ◽  
Nicole J. Fenton ◽  
Yves Bergeron
Keyword(s):  
Organic Matter ◽  
Treatment Effectiveness ◽  
Black Spruce ◽  
Wood Fiber ◽  
Site Preparation ◽  
Planting Density ◽  
Organic Layer ◽  
Mechanical Site Preparation ◽  
Decomposition Of Organic Matter ◽  
Successful Establishment

Low productivity caused by paludification in some parts of the closed black spruce (Picea mariana (Mill.) B.S.P) dominated boreal forest threatens the provision of ecosystem services, including wood fiber production. The accumulation, over time, of organic matter in paludified soils leads to an anaerobic environment that reduces microbial activity, decelerates decomposition of organic matter, and generates nutrient-poor microsites for regeneration. Consequently, it results in significant impacts on site productivity. Considering its ability to disturb the soil, mechanical site preparation (MSP) is viewed as a potential treatment that can help restore productivity of paludified sites following harvesting. We conducted a field experiment to verify if (1) the availability of microsites conducive to reforestation varies with MSP, microtopography (slope and aspect) and initial OLT conditions; (2) the growth of planted seedlings depends on the intensity of mechanical disturbance of the organic layer, type of microsite, planting density, presence of Ericaceae, and the planting position and depth; (3) there are direct and indirect causal relationships between microsites availability after MSP, OLT, microtopography, planting quality and seedlings growth; and (4) if mechanical site preparation and microsite type exposed affect the Ericaceae cover after planting. Our results confirmed that MSP is effective in establishing conditions that permit a productive regeneration cohort on these paludified sites. To ensure successful establishment of plantations on these sites, it is necessary, however, to distinguish between those that are slightly or moderately paludified from those that are highly paludified, as treatment effectiveness of different MSP types depends on organic layer thickness. Our results also show that preference should be given to some microsite types as clay and mixed-substrate microsites for planting to ensure sufficient availability of water and nutrients for seedlings.

scholarly journals Soil Disturbance and the Potential for Erosion After Mechanical Site Preparation

2002 ◽  
Vol 19 (1) ◽  
pp. 5-13 ◽  
Author(s):  
Jorge Alcázar ◽  
Paul M. Woodard ◽  
Richard L. Rothwell
Keyword(s):  
Soil Erosion ◽  
Mineral Soil ◽  
High Water ◽  
Soil Disturbance ◽  
Site Preparation ◽  
Treatment Area ◽  
Soil Movement ◽  
Mechanical Site Preparation ◽  
Physical Conditions ◽  
Water Contents

Abstract Physical soil properties created by three mechanical site preparation treatments (ripper ploughing, disc trenching, and blading) and a control were evaluated to determine the success of these different mechanical site preparation treatments in creating plantable microsites and to estimate the potential for soil erosion created by each treatment. Three sites with fine textured soils and high water contents near Whitecourt, Alberta, Canada), were selected for study. The topography at all sites was similar and characterized by slopes 3.7 to 20% in steepness and approximately 190 to 270 m in length extending from the height of land to stream bottoms. The number of planting sites and the soil characteristics suggest ripper ploughing as the best site preparation treatment in this study, with the hinge microsite as the preferred planting spot. All three treatments significantly improved the physical conditions of the soil compared to the control, although the differences among treatments were small. Soil erosion was observed on areas where blading and ripper ploughing exposed mineral soil. Gullies, which exposed the roots of seedlings, were created by water erosion in the blading treatment area. Sediment deposition in trenches was observed on ripper ploughed areas, and at times, seedlings within this treatment area were partially buried as a result of this soil movement.

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.

Structure, Deposition and Quality of Oyster Shell (Ostrea virginica Gmelin)

1944 ◽  
Vol 6c (3) ◽  
pp. 209-216 ◽  
Author(s):  
J. C. Medcof
Keyword(s):  
Specific Gravity ◽  
Late Summer ◽  
Oyster Shell ◽  
High Water ◽  
High Water Content ◽  
Functional Importance ◽  
Protein Matrix ◽  
Before And After ◽  
Porous Mass

Low quality shells are easily broken, have a high water content and low specific gravity, and contain little pearly and much chalky material. Pearly shell is secreted throughout the season before and after the chalk which it incloses. Chalky areas occur in all shells, have functional importance, are commonest in oysters that are poorest in late summer and are regular in their order of appearance and position on the shell. They are composed of large vertical calcite crystals in a porous mass of smaller crystals with a protein matrix.

scholarly journals Change in snow strength caused by rain

2012 ◽  
Vol 53 (61) ◽  
pp. 1-5 ◽  
Author(s):  
Yoichi Ito ◽  
Hiroki Matsushita ◽  
Hiroyuki Hirashima ◽  
Yasuhiko Ito ◽  
Tomoyuki Noro
Keyword(s):  
Water Content ◽  
Laboratory Experiments ◽  
Empirical Relationship ◽  
High Water ◽  
High Water Content ◽  
Snow Avalanches ◽  
Wetting Front ◽  
Snow Condition ◽  
Wet Snow ◽  
Before And After

AbstractRain-on-snow events can cause wet snow avalanches. Laboratory experiments were carried out to investigate the change in snow strength with increasing water content through rainwater percolation. Snowpack was artificially prepared consisting of a thin ice layer and fine compacted snow, and rainfall (2mmh–1) was artificially applied 22–25.5 and 49–52 hours after the snowpack was formed. Snow hardness was measured with a push–pull force gauge to indicate the snow strength before and after each rain-on-snow event. After the first rainfall, the upper half of the snowpack became wet and a rapid decrease in snow hardness was observed. After the second rainfall the rainwater penetrated the ice layer, high water content was observed above the ice layer but the hardness exceeded that estimated from an empirical relationship between hardness and water content. Micrographs of the snow particles suggest that the delay in grain coarsening observed near the wetting front induces the harder than estimated snow condition.

The effect of mechanical site preparation on ectomycorrhizae of planted white spruce seedlings in conifer-dominated boreal mixedwood forest

2008 ◽  
Vol 38 (7) ◽  
pp. 2072-2079 ◽  
Author(s):  
Lance W. Lazaruk ◽  
S. Ellen Macdonald ◽  
Gavin Kernaghan
Keyword(s):  
Picea Glauca ◽  
Untreated Control ◽  
White Spruce ◽  
Site Preparation ◽  
Organic Layer ◽  
Root Tips ◽  
Mechanical Site Preparation ◽  
Clear Cut ◽  
Mixed Treatment ◽  
Boreal Mixedwood Forest

We characterized the ectomycorrhizae (ECM) of planted white spruce ( Picea glauca (Moench) Voss) seedlings as affected by mechanical site preparation (MSP) of clear-cut conifer-dominated boreal mixedwood forest. Relative abundance, richness, and composition of the ECM community were compared among untreated control, mixed, mounded, and scalped site preparation treatments. On >11 000 root tips, we observed 16 ECM morphotypes. Those common to the nursery in which the seedlings were raised were most abundant ( Thelephora americana , Wilcoxina -like (E-strain), Amphinema byssoides , Phialocephala -like (MRA)). Seedlings in the untreated controls had lower abundances of these, but higher abundances of other ECM, which were not present in the nursery of origin but were indigenous to these forest stands. In terms of ECM composition, the “mixed” treatment was most similar to the untreated control, while the “scalped” and “mound” treatments showed significantly different ECM communities than the controls. Our results suggest that MSP may facilitate continued dominance by ECM that establish on seedlings in the nursery while slowing the natural succession towards the natural forest ECM. MSP treatments that leave some surface organic matter relatively intact may impact ECM less than those that remove or bury the organic layer.

Impacts of harvesting and mechanical site preparation on soil chemical properties of mixed-wood boreal forest sites in Alberta

1996 ◽  
Vol 76 (4) ◽  
pp. 531-540 ◽  
Author(s):  
M. G. Schmidt ◽  
S. E. Macdonald ◽  
R. L. Rothwell
Keyword(s):  
Boreal Forest ◽  
Mineral Soil ◽  
Chemical Properties ◽  
Site Preparation ◽  
Available Phosphorus ◽  
Organic Layer ◽  
Mechanical Site Preparation ◽  
Forest Sites ◽  
Mineralizable Nitrogen ◽  
Surface Mineral

We examined the impacts of harvesting and mechanical site preparation (MSP) on soil chemical properties of mixed-wood boreal forest sites in west central Alberta. Treatments included: 1) disc trencher, hinge, and trench microsites; 2) ripper plow, hinge, and trench microsites; 3) blading thin (organic layer depth < 2 cm), and thick (organic layer depth > 2 cm) microsites; 4) harvested with no site preparation; and 5) unharvested. Twenty months after harvesting, the forest floor of harvested areas with no MSP (vs. unharvested) had higher carbon:nitrogen ratios lower pH, and lower concentrations of total and mineralizable nitrogen, available phosphorus, and exchangeable bases Fifteen months after MSP, treated areas had either reduced or unchanged concentrations of total nitrogen and carbon, available phosphorus, and mineralizable nitrogen in the surface mineral soil, compared with harvested sites with no site preparation. The MSP-treated areas also had increased or unchanged pH, base saturation, and exchangeable base concentrations. Microsites adjacent to the displaced forest floor (hinge for disc and ripper treatments) or with a thicker organic layer (thick for blading) generally had higher concentrations of total nitrogen and carbon, and mineralizable nitrogen in the surface mineral soil as compared to trench and thin microsites. Key words: Forest soils, mechanical site preparation, harvesting, N, P, mixed-wood boreal forest

scholarly journals Pemanfaatan Ekstrak Daun Mahkota Dewa (Phaleria macrocarpa (Scheff.) Boerl) sebagai Pengawet Tomat

2017 ◽  
Vol 5 (2) ◽  
pp. 67 ◽  
Author(s):  
Dina Supriatni ◽  
Irwan Said ◽  
Siang Tandi Gonggo
Keyword(s):  
Vitamin C ◽  
Water Content ◽  
Leaf Extract ◽  
Tomato Fruit ◽  
High Water ◽  
High Water Content ◽  
Iodometric Titration ◽  
Before And After ◽  
Phaleria Macrocarpa

Tomato fruit is one of the fruits susceptible to decay because of its high water content. The durability of tomato can be improved by storing in a humid place or by adding of a preservative. Phaleriamacrocarpa (Scheff.) boerlleaf can act as an antibacterial due to the saponin compounds contained therein. This study aimed to investigate the phaleriamacrocarpa (Scheff.) boerlleaf extract as a preservative for tomatoes, and to determine the concentration of leaf extract to sustain tomatoes texture longer. The method used in this study was the maceration for extraction, and iodometric titration to determine of vitamin C levels before and after curing. The results showed that the pickling tomatoes using phaleriamacrocarpa (Scheff.) boerl leaf extract with a concentration of 6% sustained tomatoes up to 9 days, and the fruit decreased levels of vitamin C from 33.440 mg/100 g material into 27.580 mg/100 g of material.

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