Seasonal Variations in Ash Content of Some Michigan Forest Floor Fuels

1982 ◽  
Author(s):  
Robert M. Loomis
Keyword(s):  
Seasonal Variations ◽  
Forest Floor ◽  
Ash Content

Structure and composition of forest floor fuels in long-unburned Jeffrey pine–white fir forests of the Lake Tahoe Basin, USA

2014 ◽  
Vol 23 (3) ◽  
pp. 363 ◽  
Author(s):  
Erin M. Banwell ◽  
J. Morgan Varner
Keyword(s):  
Forest Floor ◽  
Lake Tahoe ◽  
Ash Content ◽  
Lake Tahoe Basin ◽  
Jeffrey Pine ◽  
White Fir ◽  
Composition And Structure ◽  
Tahoe Basin ◽  
Forest Floors ◽  
Spatial Locations

In spite of the mechanistic links between forest floor fuels and fire behaviour and effects, little information is available on their composition and structure. We collected fuels from well-developed forest floors in four long-unburned Jeffrey pine (Pinus jeffreyi)–white fir (Abies concolor) forests in the Lake Tahoe Basin in California and Nevada. We measured forest floor (litter, fermentation and humus, where present) load, depth, bulk density and mineral ash content at the base of each tree, near the crown drip line and beyond the crown in open gaps (n=40 Jeffrey pine, 40 white fir). We found substantial variability in composition between the two conifers’ forest floor fuels and across species. Forest floor was mounded near tree stems, with the majority of the depth (and mass) composed of fermentation fuels. Humus was present across spatial locations, but was patchier with increasing distance from trees. Ash content varied between trees (fir>pine) and with depth (humus>fermentation>litter). Results highlight the high spatial variation in forest floor fuels and underscore the need for building a greater understanding of forest floor fuels in long-unburned sites.

Cycling of aluminum and nutrients in litterfall of a red spruce (Picearubens Sarg.) stand in Maine

1989 ◽  
Vol 19 (1) ◽  
pp. 18-23 ◽  
Author(s):  
Lindsey E. Rustad ◽  
Christopher S. Cronan
Keyword(s):  
Elemental Composition ◽  
Seasonal Variations ◽  
Forest Floor ◽  
Red Spruce ◽  
Seasonal Differences ◽  
Annual Basis ◽  
Biological Cycling

Annual and seasonal variations in the concentration and total return of Al, Fe, Mn, Ca, Mg, K, Na, C, N, and P in litterfall were studied for a period of 2 years in a mature red spruce stand in central Maine. Seasonal differences in elemental composition were large. The greatest change occurred in the autumn, when the concentrations of Al, Fe, N, P, and K declined, while Ca and Mg concentrations peaked. On an annual basis, litterfall contributed 0.5, 0.5, 1.1, 13.8, 2.1, 5.3, 0.2, 17.6, and 1.3 kg •ha−1•year−1 of Al, Fe, Mn, Ca, Mg, K, Na, N, and P, respectively, to the forest floor. The input of Al in litterfall was 10 times as great as that in net canopy throughfall, indicating that the biological cycling of Al in litterfall was an important source of Al to the forest floor at this site.

Proximate Analysis of Pacific Herring (Clupea pallasii) and an Evaluation of Tester's "Fat Factor"

1959 ◽  
Vol 16 (5) ◽  
pp. 679-684 ◽  
Author(s):  
J. R. McBride ◽  
R. A. MacLeod ◽  
D. R. Idler
Keyword(s):  
Seasonal Variations ◽  
Oil Content ◽  
Proximate Analysis ◽  
Ash Content ◽  
Pacific Herring ◽  
Average Deviation ◽  
Clupea Pallasii

Samples of Pacific herring (Clupea pallasii) were obtained from commercial catches made at approximately monthly intervals for a period of a year. These samples were analysed for their water, oil, protein and ash content. The seasonal variations obtained in the analytical values in general confirmed those observed previously for this species of fish.When Tester's "fat factor" determined by dividing the weight of the fish by its weight in water was used to calculate the oil content of herring, the average deviation of the calculated oil content from that determined experimentally was 15% and the range of deviation was 2 to 49%. Use of the "fat factor" as a practical means of determining the oil content of herring is not recommended.

Seasonal variation in the chemical constituents of the brown algae Macrocystis integrifolia and Nereocystis luetkeana

1984 ◽  
Vol 62 (11) ◽  
pp. 2229-2236 ◽  
Author(s):  
Karl-Gunnar Rosell ◽  
Lalit M. Srivastava
Keyword(s):  
Seasonal Variations ◽  
Brown Algae ◽  
Alginic Acid ◽  
Major Elements ◽  
Ash Content ◽  
Inorganic Elements ◽  
Sodium Calcium ◽  
Macrocystis Integrifolia ◽  
Calcium Magnesium ◽  
Alginate Content

Ash, mannitol, alginate content, and inclusion levels of 27 inorganic elements in the brown algae Macrocystis integrifolia and Nereocystis luetkeana were monitored monthly over a period of 2 years. In addition, the composition and viscosity of the alginate were determined. Potassium, sodium, calcium, magnesium and phosphorus were the major elements present. Others, in decreasing amounts, included iodide, strontium, boron, iron, arsenic, aluminum, zinc, barium, manganese, copper, and cobalt. Some of these elements were accumulated to high concentrations in the thallus when compared with their concentrations in seawater. Marked seasonal variations were observed for potassium and phosphate, with high levels in winter and low levels in summer. Boron and iodide showed a reverse trend. Among the major elements, sodium, calcium, and magnesium showed no seasonal variations. Most of the inorganic elements, except potassium, were more abundant in the blade compared with the stipe. Leaching experiments with organic and inorganic solvents suggested that the alkali metals, sodium and potassium, were present mostly as inorganic salts, while divalent cations, calcium, magnesium, and strontium, were probably bound to alginic acid. Organic solvents did not leach appreciable quantities of the inorganic elements. The ash content in both algae was minimum (24%) in summer and maximum (49%) during winter, mainly because of the higher concentration of potassium in winter. Nereocystis showed higher values of ash than Macrocystis, and ash content was slightly higher in the stipe than in the blade tissues. The mannitol content ranged from 2 to 16% and alginate content from 19 to 31% of dry weight, both compounds showing higher values during the summer. Far more mannitol was present in the blade than in the stipe tissue, whereas the alginic acid content was slightly higher in the stipe than in the blade tissue. The mannuronate–guluronate ratio of alginate varied between 1.2 and 1.7 and the viscosity between 800 and 2000 cps.

Seasonal variation in two species of unionid clams from Manitoba, Canada: biomass

1980 ◽  
Vol 58 (11) ◽  
pp. 1980-1983 ◽  
Author(s):  
Judith D. Huebner
Keyword(s):  
Seasonal Variation ◽  
Water Content ◽  
Shell Length ◽  
Seasonal Variations ◽  
Dry Weight ◽  
Ash Content ◽  
Reproductive Timing ◽  
Average Water ◽  
Anodonta Grandis ◽  
The Relationship

The relationship between dry weight and shell length for Anodonta grandis and Lampsilis radiata is log dry weight = a + 3.0317 log shell length, where a varies seasonally. Average water content of clams varies seasonally from 83.18% for both species in February and May to 85.02% for L. radiata in July and 87.56% for A. grandis in July and October. Mean ash content of L. radiata (19.21%) is higher than that of A. grandis (12.68%) except in October (20.94%) when marsupia are filled with glochidia. Differences in reproductive timing and length of glochidial retention contribute to some of the seasonal variations in biomass in A. grandis and L. radiata.

Seasonal variations in AADSAS applicants

1985 ◽  
Vol 49 (6) ◽  
pp. 445-447
Author(s):  
E Solomon ◽  
D Stoll
Keyword(s):  
Seasonal Variations
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