Effect of timber harvesting on microbial biomass fluxes in a northern Rocky Mountain forest soil

1986 ◽  
Vol 16 (5) ◽  
pp. 1076-1081 ◽  
Author(s):  
James A. Entry ◽  
Nellie M. Stark ◽  
Howard Loewenstein
Keyword(s):  
Microbial Biomass ◽  
Snow Cover ◽  
Forest Soil ◽  
Soil Ph ◽  
Rocky Mountain ◽  
Timber Harvesting ◽  
Soil Microbial Activity ◽  
Mountain Forest ◽  
Clear Cut ◽  
Soil Temperatures

Microbial biomass and relative bacterial and fungal percentages were measured in organic forest soil from a Rocky Mountain site subjected to four harvesting treatments: RL, clear-cut and residue left; RR, clear-cut and residue removed; RB, clear-cut and residue burned; C, uncut control. Microbial biomass peaked in spring and fall regardless of treatment. Biomass in soil from the RB treatment was significantly (p < 0.05) less than that in soil from the other treatments most of the year; biomass did not significantly differ in soil from the RR and C treatments. During summer and winter, microbial biomass in soil from the RL treatment was significantly greater than that in soil from any other treatment, probably because of the large amount of organic residue left after harvest; moreover, this residue insulated the soil, preventing it from drying or freezing. At soil temperatures above 5 °C, microbial biomass correlated positively with soil moisture regardless of treatment; at soil temperatures below 2.5 °C, microbial biomass correlated positively with increasing soil temperature. During periods with snow cover, bacterial and fungal percentages were roughly equal regardless of treatment; during the rest of the year, bacterial percentages were high in the RL and RB treatments and low in the RR and C treatments. During periods without snow cover, bacterial and fungal percentages correlated positively with increasing soil pH; however, at near-freezing temperatures the percentage of bacteria and fungi seemed unaffected by soil pH. These findings suggest that treatments that remove a large portion of available site nutrients while reducing soil microbial activity could limit stand development.

Effect of timber harvesting on extractable nutrients in a northern Rocky Mountain forest soil

1987 ◽  
Vol 17 (7) ◽  
pp. 735-739 ◽  
Author(s):  
James A. Entry ◽  
Nellie M. Stark ◽  
Howard Loewenstein
Keyword(s):  
Forest Soil ◽  
Rocky Mountain ◽  
Timber Harvesting ◽  
Organic Horizon ◽  
Mountain Forest ◽  
Decomposition Rates ◽  
Total N ◽  
Clear Cut ◽  
Extractable P ◽  
Extractable Nutrients

Extractable nutrients were measured for 2 years in the organic horizon of a forest soil from a Rocky Mountain site subjected to four harvesting treatments (clear-cut and residue left, clear-cut and residue removed, clear-cut and residue burned, uncut control). Concentrations of extractable P, Ca, K, and Mg were significantly lower in winter than in spring, fall, or summer in all treatments except the clear-cut with residue left; decomposition rates of lodgepole pine (Pinuscontorta var. latifolia Engelm.) needles also were significantly higher in this than in any of the other treatments. Concentrations of extractable B, Cu, Fe, Mn, Na, Si, Zn, and total N did not differ significantly regardless of treatment or season, nor did concentrations of nutrients leached through the organic horizon, which suggests that litter acts as a nutrient sink, retaining nutrients on the cation exchange and releasing them slowly. Managers should leave as much organic residue as possible on harvested sites where soil nutrients are suspected of limiting tree growth to ensure adequate nutrition and moisture for conifer regeneration.

Microbial community structure and activity in a Colorado Rocky Mountain forest soil scarred by slash pile burning

2007 ◽  
Vol 39 (5) ◽  
pp. 1111-1120 ◽  
Author(s):  
Aida E. Jiménez Esquilín ◽  
Mary E. Stromberger ◽  
William J. Massman ◽  
John M. Frank ◽  
Wayne D. Shepperd
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Forest Soil ◽  
Microbial Community Structure ◽  
Rocky Mountain ◽  
Mountain Forest ◽  
Structure And Activity

Microbial respiration and biomass in soil of a lodgepole pine stand acidified with elemental sulphur

1989 ◽  
Vol 19 (8) ◽  
pp. 955-961 ◽  
Author(s):  
S. Visser ◽  
D. Parkinson
Keyword(s):  
Microbial Biomass ◽  
Soil Ph ◽  
Glucose Utilization ◽  
Microbial Respiration ◽  
Mineral Soil ◽  
Rocky Mountain ◽  
Dry Weight ◽  
Elemental Sulphur ◽  
Utilization Patterns ◽  
Time Required

A study was conducted to determine the effects of elemental sulphur (So) dust pollution on pH, microbial respiration and biomass, glucose mineralization dynamics, and selected soil chemical characteristics in the organic and mineral soil of a Pinuscontorta Dougl. stand near Rocky Mountain House, Alberta. Six sampling sites were established 50 to 750 m downwind of a So block located at a sour gas processing facility. The sites represented a gradient in sulphur (S) concentrations (1072 to 35 800 μg•(g soil)−1) and pH (4.9 to 1.6). In the organic horizon, So dust significantly reduced the pH from a mean of 4.1 to 2.3 and microbial biomass from 753 to 130 mg C•(100 g dry weight soil)−1. Increasing acidification also reduced total Ca, Mg, K, Mn, and P. A reduction in the cations, P, and microbial biomass was particularly evident at a soil pH below 3.3. Glucose mineralization patterns were altered as a result of acidification. The time required by the soil microbial biomass to attain maximum CO2 efflux following glucose enrichment increased from 11 h in the least acidified soil (pH 4.1) to 38 h in the most acidified soil (pH 2.3). Soil respiration was not significantly affected by soil acidification. Microbial biomass was highly correlated with pH. The mineral soil demonstrated a decreasing trend in pH (5.0 to 3.7) with increasing S levels (79 to 499 μg•(g dry weight soil)−1), but no significant effects on respiration and biomass were detected. However, glucose utilization patterns revealed a tendency towards a slower responding and less efficient biomass with increasing acidity. The time to reach maximum CO2 efflux following glucose enrichment increased from 14 h in the least acidified site (pH 5.0) to 26 h in the most acidified site (pH 3.7). The use of biomass measurements coupled with glucose utilization patterns for providing insight into the effects of pollutant stress on soil microorganisms is discussed.

scholarly journals The Influence of Selected Meteorological Factors on Microbial Biomass and Mineralization of Two Organic Fertilizers

2011 ◽  
Vol 39 (1) ◽  
pp. 107
Author(s):  
Mignon S. SANDOR ◽  
Traian BRAD ◽  
Aurel MAXIM ◽  
Constantin TOADER
Keyword(s):  
Biological Activity ◽  
Microbial Biomass ◽  
Soil Ph ◽  
Soil Microbial Biomass ◽  
Organic Fertilizers ◽  
Barley Straw ◽  
Short Term ◽  
Soil Microbial ◽  
Fertilized Soil ◽  
Mineralization Processes

A mesocosm study was conducted in order to evaluate the effects of short-term rainfall and temperature variation on soil microbial biomass and bacteria to fungi ratio. In addition, the relation between the decomposition process of two organic fertilizers, cattle manure and barley straw, and the activity of soil microbial biomass was also studied. In order to assess the effect of biological activity on soil fertility the dynamics of soil pH, N-NO3-, N-NH4+, Corg and Nt during plant growing season was measured. The results suggest that short-term variation of climate had a significant effect on microbial biomass with dry periods distinguished by a reduced microbial biomass compared to wet periods. The ratio bacteria to fungi seems also to be sensitive to variations in rainfall and temperature regime, however further studies are required to draw a definitive conclusion. Regarding the type of fertilizer used, the straw treatments showed higher microbial biomass than the manure treatments, but higher decomposition rate was observed in manure fertilized soil. The effect of soil biological activity on soil pH was limited for both manure and straw treatments while the changes of the soil nitrate amounts are related to the microbial biomass. The study indicates that nitrate immobilization and mineralization processes are influenced by meteorological conditions and microbial biomass dynamics. In contrast, soil organic carbon and total nitrogen did not seem to be affected by variations in temperature, rainfall and microbial activity.

Long-term effects of fire on the composition and activity of the soil microflora of a subalpine, coniferous forest

1980 ◽  
Vol 58 (15) ◽  
pp. 1704-1721 ◽  
Author(s):  
J. Bissett ◽  
D. Parkinson
Keyword(s):  
Microbial Biomass ◽  
Bacterial Flora ◽  
Mineral Soil ◽  
Coniferous Forest ◽  
Soil Microflora ◽  
Subalpine Forest ◽  
Long Term Effects ◽  
Soil Horizons ◽  
Cellulose Decomposition ◽  
Soil Temperatures

The biomass, community composition, and metabolic activity of soil microorganisms were studied in adjacent burnt and unburnt areas of spruce–fir subalpine forest razed 6 years previously by a moderately severe natural fire. Similar levels of microbial biomass were observed at comparable burnt and unburnt sites, although the ratio of fungal to bacterial biomass was higher in the unburnt soils. The decreased acidity of the surface horizons in the burn probably tended to favor the development of a bacterial flora rather than a fungal flora. Microbial biomass in the burnt sites peaked earlier in the season than in the unburnt sites in response to the warmer soil temperatures and earlier thaw in the spring in the burn area.Significant differences in the species composition of the mycoflora in the organic soil horizons were observed between the burnt and unburnt sites. Apparently, these were related to qualitative differences in the recent litter. Phoma, Cladosporium, and Botrytis, which are usually associated with early stages of decomposition of herbaceous litter, were more common in the burnt soil. The mycoflora of the mineral soil horizons varied considerably from one burn site to another, possibly reflecting the geographical variation in the intensity of the burn. In overall composition, however, the mycoflora in the mineral soil horizons of the burn was not appreciably different from that of the unburnt sites.Higher laboratory rates of respiration and cellulose decomposition were observed for soil samples from the undisturbed forest. However, the rate of decomposition of cellulose in the field was much higher in the burnt sites, probably as a result of the higher soil temperatures in the burn area. Low soil temperature was concluded to be the main factor limiting microbial activities in the study area, and the removal of the insulating plant canopy and increased heat absorption by the ash in the burn area were found to increase decomposition rates, at least at this stage in the succession following the disturbance of fire.

scholarly journals Ant nests as a microbial hot spots in a long-term heavy metal-contaminated soils

2021 ◽  
Author(s):  
Beata Klimek ◽  
Hanna Poliwka-Modliborek ◽  
Irena M. Grześ
Keyword(s):  
Microbial Biomass ◽  
Microbial Activity ◽  
Respiration Rate ◽  
Metal Content ◽  
Soil Microbial Activity ◽  
Bulk Soil ◽  
Lasius Niger ◽  
Soil Microbial ◽  
Ant Nests

AbstractInteractions between soil fauna and soil microorganisms are not fully recognized, especially in extreme environments, such as long-term metal-polluted soils. The purpose of the study was to assess how the presence of Lasius niger ants affected soil microbial characteristics in a long-term metal-polluted area (Upper Silesia in Poland). Paired soil samples were taken from bulk soil and from ant nests and analysed for a range of soil physicochemical properties, including metal content (zinc, cadmium, and lead). Microbial analysis included soil microbial activity (soil respiration rate), microbial biomass (substrate-induced respiration rate), and bacteria catabolic properties (Biolog® ECO plates). Soil collected from ant nests was drier and was characterized by a lower content of organic matter, carbon and nitrogen contents, and also lower metal content than bulk soil. Soil microbial respiration rate was positively related to soil pH (p = 0.01) and negatively to water-soluble metal content, integrated into TIws index (p = 0.01). Soil microbial biomass was negatively related to TIws index (p = 0.04). Neither soil microbial activity and biomass nor bacteria catabolic activity and diversity indices differed between bulk soil and ant nests. Taken together, ant activity reduced soil contamination by metals in a microscale which support microbial community activity and biomass but did not affect Biolog® culturable bacteria.

COMPARISON OF OBSERVATIONS AND MACROCLIMATIC MODEL ESTIMATES OF MONTHLY WINTER SOIL TEMPERATURES AT OTTAWA

1985 ◽  
Vol 65 (1) ◽  
pp. 109-122 ◽  
Author(s):  
L. M. DWYER ◽  
H. N. HAYHOE
Keyword(s):  
Snow Cover ◽  
Predictive Models ◽  
Regression Models ◽  
Stepwise Regression ◽  
Regression Coefficients ◽  
Data Sets ◽  
Regression Equations ◽  
Grass Cover ◽  
Partial Regression ◽  
Soil Temperatures

Estimates of monthly soil temperatures under short-grass cover across Canada using a macroclimatic model (Ouellet 1973a) were compared to monthly averages of soil temperatures monitored over winter at Ottawa between November 1959 and April 1981. Although the fit between monthly estimates and Ottawa observations was generally good (R for all months and depths 0.10, 0.20, 0.50, 1.00 and 1.50 m was 0.90), it was noted that midwinter estimates were generally below observed temperatures at all soil depths. Data sets used in the development of the original Ouellet (1973a) multiple regression equations were collected from stations across Canada, many of which have reduced snow cover. It was found that the buffering capability of the snow cover accumulated at Ottawa during the winter months was underestimated by the pertinent partial regression coefficients in these equations. The coefficients were therefore modified for the Ottawa station during the winter months. The resultant regression models were used to estimate soil temperature during the winters of 1981–1982 and 1982–1983. Although the Ottawa-based models included fewer variables because of the smaller data base available from a single site, comparisons of model estimates and observations were good (R = 0.84 and 0.91) and midwinter estimates were not consistently underestimated as they were using the original Ouellet (1973a) model. Reliable monthly estimates of soil temperatures are important since they are a necessary input to more detailed predictive models of daily soil temperatures. Key words: Regression model, snowcover, stepwise regression, variable selection

Sign in / Sign up

Export Citation Format

Share Document