Effect of forest harvesting and slash piling on microbial biomass and respiration in Newfoundland boreal forests

2007 ◽  
Vol 87 (4) ◽  
pp. 455-458 ◽  
Author(s):  
Martin T Moroni ◽  
Paul Q Carter ◽  
Dean W Strickland ◽  
Franz Makeschin ◽  
Don-Roger Parkinson ◽  
...  
Keyword(s):  
Microbial Biomass ◽  
Key Words ◽  
Boreal Forests ◽  
Fungal Biomass ◽  
Forest Harvesting ◽  
Organic Layer ◽  
Total Microbial Biomass ◽  
Organic Layers ◽  
Respiration Rates ◽  
Fumigation Extraction

Clearcutting Newfoundland boreal forests significantly reduced organic layer fungal and total microbial biomass in clearcut areas with and without slash cover, compared with forested plots. However, aerobically incubated respiration rates were highest in organic layers from clearcut areas under slash, intermediate under forests, and lowest from clearcut areas without slash. Key words: Carbon, ergosterol, fumigation–extraction, fungal biomass, harvest slash, nitrogen

scholarly journals The Influence of dairy manure on atrazine and 2,4-dichlorophenoxyacetic acid mineralization in pasture soils

1995 ◽  
Vol 75 (3) ◽  
pp. 379-383 ◽  
Author(s):  
James A. Entry ◽  
William H. Emmingham
Keyword(s):  
Microbial Biomass ◽  
Key Words ◽  
Fungal Biomass ◽  
Bacterial Biomass ◽  
Dairy Manure ◽  
Dichlorophenoxyacetic Acid ◽  
Manure Application ◽  
Herbicide Degradation ◽  
Degradation Rates ◽  
2,4 Dichlorophenoxyacetic Acid

The influence of manure application to pasture soils on bacterial and fungal biomass and the atrazine (2 chloro-4 [ethylamino]-6[isopropylamino]-s-triazine) and 2,4-D (2,4 dichlorophenoxyacetic acid) mineralization was assessed in microcosms using radiometric techniques. Additions of 5 tonnes manure ha−1 yr−1 were made to three pasture soils over 20 yr in western Oregon at a rate of 0.42 t ha−1 each month. No manure or fertilizer was added to control treatments. We found greater amounts of total fungal and bacterial biomass in soils that received added manure. There were no differences among active bacterial and fungal biomass between pasture soils that received manure application and pasture soils that received no manure. Greater amounts of atrazine and 2,4-D were mineralized when manure was applied than when soil received no manure or fertilizer. Greater amounts of atrazine and 2,4-D were mineralized in the spring than in summer, fall or winter. Results of this study indicate that the application of dairy manure to pasture soils will significantly increase herbicide degradation rates. Key words: Pasture soils, microbial biomass, manure application, atrazine, 2,4-D, herbicide mineralization

Saproxylic insect assemblages in Canadian forests: diversity, ecology, and conservation

2008 ◽  
Vol 140 (4) ◽  
pp. 453-474 ◽  
Author(s):  
David W. Langor ◽  
H.E. James Hammond ◽  
John R. Spence ◽  
Joshua Jacobs ◽  
Tyler P. Cobb
Keyword(s):  
Forest Management ◽  
Boreal Forests ◽  
Dead Wood ◽  
Sustainable Forest Management ◽  
Forest Harvesting ◽  
Stand Age ◽  
Managed Forests ◽  
Saproxylic Insects ◽  
Associated Species ◽  
Experimental Burns

AbstractSaproxylic insect assemblages inhabiting dead wood in Canadian forests are highly diverse and variable but quite poorly understood. Adequate assessment of these assemblages poses significant challenges with respect to sampling, taxonomy, and analysis. Their assessment is nonetheless critical to attaining the broad goals of sustainable forest management because such species are disproportionately threatened elsewhere by the reductions in dead wood generally associated with commercial exploitation of northern forests. The composition of the saproxylic fauna is influenced by many factors, including tree species, degree of decay, stand age, and cause of tree death. Wildfire and forest harvesting have differential impacts on saproxylic insect assemblages and on their recovery in postdisturbance stands. Exploration of saproxylic insect responses to variable retention harvesting and experimental burns is contributing to the development of prescriptions for conserving saproxylic insects in boreal forests. Understanding of processes that determine diversity patterns and responses of saproxylic insects would benefit from increased attention to natural history. Such work should aim to provide a habitat-classification system for dead wood to better identify habitats (and associated species) at risk as a result of forest management. This tool could also be used to improve strategies to better maintain saproxylic organisms and their central nutrient-cycling functions in managed forests.

Wounding of aspen roots promotes suckering

2004 ◽  
Vol 82 (3) ◽  
pp. 310-315 ◽  
Author(s):  
Erin C Fraser ◽  
Victor J Lieffers ◽  
Simon M Landhäusser
Keyword(s):  
Populus Tremuloides ◽  
Growth Rates ◽  
Growing Season ◽  
Organic Layer ◽  
Trembling Aspen ◽  
Layer Depth ◽  
Injury Type ◽  
Organic Layers ◽  
Root Injury ◽  
Root Sucker

In early May, 1-m sections of trembling aspen (Populus tremuloides Michx.) roots in a forest cutblock were carefully exposed and examined for damage. Undamaged roots were subjected to one of three wounding treatments (scrape, sever, or uninjured control) and were then reburied to either the full normal organic layer depth or to one third of the normal depth. Following one growing season, the roots were reexposed and assessed for aspen sucker numbers and growth rates. Results indicate that injured roots produced suckers nearly twice as often as uninjured roots. Further, injured roots produced more suckers per root, and these suckers were taller and had greater leaf area. Roots buried under shallow organic layers also generated more suckers, regardless of injury type. The side of injury (distal or proximal) did not affect any of the measured variables. The present study suggests that moderate wounding of aspen roots increases initial sucker numbers and growth rates.Key words: trembling aspen, root sucker, root injury, regeneration.

Measuring unsaturated hydraulic conductivity (K(ψm)) of the F and H soil organic layers at small matric potential (ψm)

2011 ◽  
Vol 91 (6) ◽  
pp. 965-968
Author(s):  
B. Wilske ◽  
E. A. Johnson
Keyword(s):  
Hydraulic Conductivity ◽  
Large Data ◽  
Cold Climate ◽  
Organic Layer ◽  
Matric Potential ◽  
Large Variability ◽  
Organic Layers ◽  
Soil Organic Layer ◽  
Unsaturated Hydraulic Conductivity ◽  
Constant Head

Wilske, B. and Johnson, E. A. 2011. Measuring unsaturated hydraulic conductivity (K(ψm)) of the F and H soil organic layers at small matric potential (ψm). Can. J. Soil Sci. 91: 965–968. K(ψm) of the soil organic layers is a key parameter to assess water redistribution in cold-climate forests. This study tested the twin suction disc apparatus (TSD) as a new method to measure K(ψm) of the F and H layers directly. We compared the results to two studies. One represents a large data base, the other used similar sample locations; but both derived K(ψm) from combining two methods, i.e., pressure plate measurements combined with the instantaneous profile technique or the constant head approach. The TSD data are consistent with previous results considering the large variability in K(ψm) from the combined methods. This suggests that the TSD method represents an alternative to determine K(ψm) of the soil organic layer.

Distillation in a boreal mossy forest floor

2003 ◽  
Vol 33 (4) ◽  
pp. 663-671 ◽  
Author(s):  
T J Carleton ◽  
K M.M Dunham
Keyword(s):  
Boreal Forests ◽  
Forest Floor ◽  
Growing Season ◽  
Mass Gain ◽  
Dew Point ◽  
Organic Layers ◽  
Dry Down ◽  
Microclimate Monitoring ◽  
Capillary Wicking

The feathermoss-dominated floor of coniferous boreal forests can experience midsummer drought. From ecophysiological studies, based on single shoots, it is unclear how the live moss carpet can survive such stress. External capillary wicking from the lowest, moist organic layers is one possibility. Another is evaporation from the same source followed by condensation on the upper, live moss shoots (distillation). A laboratory wicking experiment showed that, under ideal conditions, much of the organic forest floor profile can be supplied with moisture by capillarity from below. However, the uppermost live moss shoots could not be hydrated by this mechanism. In contrast, a gravimetric field experiment indicated nocturnal mass gain by turves of live moss shoots, placed in situ on the forest floor, during dry-down conditions. For turf treatments with an underlying vapour barrier, no such mass gain was evident. Turf treatments with a vapour barrier on top were little different from controls. It is concluded that nocturnal distillation occurs during all summer dry-downs and that this is likely to ensure moss shoot survival during diurnal periods of drought stress. Limited microclimate monitoring indicated that nocturnal cooling at the forest floor surface was sufficient to bring the moss shoot surfaces to the dew point and to reverse the daytime temperature gradient through the organic forest floor profile. This appears to be most noticeable late in the growing season when the lowermost organic layers have progressively warmed throughout the summer.

Metal–organic layer derived metal hydroxide nanosheets for highly efficient oxygen evolution

2019 ◽  
Vol 55 (38) ◽  
pp. 5467-5470 ◽  
Author(s):  
Wen-Da Zhang ◽  
Xiaodong Yan ◽  
Tao Li ◽  
Yong Liu ◽  
Qiu-Ting Fu ◽  
...  
Keyword(s):  
Oxygen Evolution ◽  
Metal Hydroxide ◽  
Organic Layer ◽  
Organic Layers ◽  
Highly Efficient ◽  
Metal Organic ◽  
Better Than

Ultrathin metal hydroxide nanosheets derived from metal–organic layers serving as electrocatalysts displayed highly efficient oxygen evolution even better than commercial IrO2.

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