Soil nitrogen mineralization and immobilization in response to periodic prescribed fire in a loblolly pine plantation

1989 ◽  
Vol 19 (6) ◽  
pp. 816-820 ◽  
Author(s):  
Randy L. Bell ◽  
Dan Binkley
Keyword(s):  
Ammonium Sulfate ◽  
Loblolly Pine ◽  
Nitrogen Mineralization ◽  
Prescribed Fire ◽  
Mineral Soil ◽  
N Availability ◽  
Net N Mineralization ◽  
Burn Treatment ◽  
Soil C ◽  
Poor Site

Additions of 15N-labelled ammonium sulfate were used to evaluate the effects of burning at 2- and 4-year intervals during a 24-year period on nitrogen mineralization and immobilization in a loblolly pine (Pinustaeda L.) stand. Net N mineralization in 10-day laboratory incubations of Oe + Oa plus 0–10 cm mineral soil was greatest in the control (210 mg N/m2), intermediate for the 2 year interval burn treatment (87 mg N/m2), and lowest for the 4 year interval burn treatment (78 mg N/m2). Forest floor and mineral soil C/N ratios were greater for the burn treatments than for the control. All samples showed >95% immobilization of added 15N ammonium sulfate, the pattern being 2-year interval >4-year interval control. Both burning regimes appeared to increase N immobilization and decrease N availability on this very N-poor site.

scholarly journals Long-Term Effects of Repeated Prescribed Fire and Fire Surrogate Treatments on Forest Soil Chemistry in the Southern Appalachian Mountains (USA)

Fire ◽  
2020 ◽  
Vol 3 (2) ◽  
pp. 20
Author(s):  
Christopher J. Dukes ◽  
T. Adam Coates ◽  
Donald L. Hagan ◽  
W. Michael Aust ◽  
Thomas A. Waldrop ◽  
...  
Keyword(s):  
Prescribed Fire ◽  
Mineral Soil ◽  
Appalachian Mountains ◽  
Fuel Reduction ◽  
Burn Treatment ◽  
Soil C ◽  
Southern Appalachian Mountains ◽  
Management Objectives ◽  
Southern Appalachian

From 2001–2018, a series of fuel reduction and ecosystem restoration treatments were implemented in the southern Appalachian Mountains near Asheville, North Carolina, USA. Treatments consisted of prescribed fire (four burns), mechanical cutting of understory shrubs and mid-story trees (two cuttings), and a combination of both cutting and prescribed fire (two cuts + four burns). Soils were sampled in 2018 to determine potential treatment impacts for O horizon and mineral soil (0–10 cm depth) carbon (C) and nitrogen (N) and mineral soil calcium (Ca), magnesium (Mg), phosphorus (P), potassium (K), and pH. Results suggested that mean changes in O horizon C and N and mineral soil C, N, C:N, Ca, and P from 2001–2018 differed between the treatments, but only mineral soil C, N, C:N, and Ca displayed differences between at least one fuel reduction treatment and the untreated control. One soils-related restoration objective was mineral soil N reduction and the cut + burn treatment best achieved this result. Increased organic matter recalcitrance was another priority, but this was not obtained with any treatment. When paired with previously reported fuels and vegetation results from this site, it appeared that continued use of the cut + burn treatment may best achieve long-term management objectives for this site and other locations being managed for similar long-term restoration and fuels management objectives.

Nitrogen mineralization in short-rotation tree plantations along a soil nitrogen gradient

2006 ◽  
Vol 36 (5) ◽  
pp. 1236-1242 ◽  
Author(s):  
Kye-Han Lee ◽  
Shibu Jose
Keyword(s):  
Loblolly Pine ◽  
Nitrogen Mineralization ◽  
Soil Nitrogen ◽  
N Mineralization ◽  
Populus Deltoides ◽  
Sandy Loam ◽  
Stem Volume ◽  
N Availability ◽  
Net N Mineralization ◽  
The Impact

We measured soil nitrogen (N) mineralization along an N fertilization gradient (control; irrigation only (I + 0 N); irrigation with 56 (I + 56 N), 112 (I + 112 N), and 224 (I + 224 N) kg N·ha–1·year–1, respectively) in 7-year-old cottonwood (Populus deltoides Marsh.), cherrybark oak (Quercus falcata Michx. var. pagodifolia Ell.), American sycamore (Platanus occidentalis L.), and loblolly pine (Pinus taeda L.) plantations established on a well-drained Redbay sandy loam (a fine loamy, siliceous, thermic Rhodic Paleudult), in Florida, USA. Nitrogen mineralization was measured monthly for 1 year, beginning in April 2001, with the buried bag incubation technique. Irrigation alone or fertigation (irrigation + N) affected annual net N mineralization rates under hardwood species, but no effect was found under loblolly pine. Overall, the rates were higher under cherrybark oak (108 kg N·ha–1·year–1) and cottonwood (101 kg N·ha–1·year–1) than under sycamore (82 kg N·ha–1·year–1) and loblolly pine (75 kg N·ha–1·year–1). Significant correlations were observed between N mineralization and stem volume in all species but loblolly pine. These results suggest that N mineralization response to irrigation or fertigation (irrigation + N) is heavily dependent on species-specific feedback mechanisms. Our results also support the hypothesis that the N mineralization versus productivity relationship is a fundamental feature of forests, resulting from the impact of N availability on productivity and the long-term feedback effects of vegetation on N availability.

Wildfire mitigation strategies affect soil enzyme activity and soil organic carbon in loblolly pine (Pinus taeda) forests

2006 ◽  
Vol 36 (12) ◽  
pp. 3148-3154 ◽  
Author(s):  
R EJ Boerner ◽  
T A Waldrop ◽  
V B Shelburne
Keyword(s):  
Enzyme Activity ◽  
Acid Phosphatase ◽  
Pinus Taeda ◽  
Loblolly Pine ◽  
Prescribed Fire ◽  
Mineral Soil ◽  
Post Treatment ◽  
Soil Organic C ◽  
Organic C ◽  
Soil C

We quantified the effects of three wildfire hazard reduction treatments (prescribed fire, thinning from below, and the combination of fire and thinning), and passive management (control) on mineral soil organic C, and enzyme activity in loblolly pine (Pinus taeda L.) forests on the Piedmont of South Carolina. Soil organic C was reduced by thinning, either alone or with prescribed fire, and this effect persisted through the fourth post-treatment year. Fire also resulted in reduced soil organic C, but not until several years after treatment. Soil C/N ratio initially increased after fire, either alone or with thinning, but this difference did not persist. The activities of three soil enzymes (acid phosphatase, chitinase, and phenol oxidase) in the upper mineral soil were quantified as measures of microbial activity. During the fourth post-treatment year we observed significant stimulation of all three enzyme systems as a result of thinning or thinning and burning. Although the patterns of variation in acid phosphatase and chitinase activity among treatments were similar during the first and fourth post-treatment years, the first-year treatment effects were not statistically significant. Given the management objective of utilizing these stands for timber production, the increased potential for rapid nutrient turnover offered by thinning gives this approach advantages over prescribed fire; however, management for maximum long-term storage of soil C may be better facilitated by prescribed fire.

Nitrogen storage and availability during stand development in a New Zealand Nothofagus forest

2002 ◽  
Vol 32 (2) ◽  
pp. 344-352 ◽  
Author(s):  
P W Clinton ◽  
R B Allen ◽  
M R Davis
Keyword(s):  
New Zealand ◽  
Forest Floor ◽  
Woody Debris ◽  
Mineral Soil ◽  
Stand Development ◽  
N Availability ◽  
Net N Mineralization ◽  
Nitrogen Storage ◽  
Nothofagus Forest ◽  
Mature Stands

Stemwood production, N pools, and N availability were determined in even-aged (10, 25, 120, and >150-year-old) stands of a monospecific mountain beech (Nothofagus solandri var. cliffortioides (Hook. f.) Poole) forest in New Zealand recovering from catastrophic canopy disturbance brought about by windthrow. Nitrogen was redistributed among stemwood biomass, coarse woody debris (CWD), the forest floor, and mineral soil following disturbance. The quantity of N in stemwood biomass increased from less than 1 kg/ha in seedling stands (10 years old) to ca. 500 kg/ha in pole stands (120 years old), but decreased in mature stands (>150 years old). In contrast, the quantity of N stored in CWD declined rapidly with stand development. Although the mass of N stored in the forest floor was greatest in the pole stands and least in the mature stands, N availability in the forest floor did not vary greatly with stand development. The mass of N in the mineral soil (0–100 mm depth) was also similar for all stands. Foliar N concentrations, net N mineralization, and mineralizable N in the mineral soil (0–100 mm depth) showed similar patterns with stage of stand development, and indicated that N availability was greater in sapling (25 years old) and mature stands than in seedling and pole stands. We conclude that declining productivity in older stands is associated more with reductions in cation availability, especially calcium, than N availability.

Empirical relationships between temperature and nitrogen availability across North American forests

1992 ◽  
Vol 22 (5) ◽  
pp. 707-712 ◽  
Author(s):  
Xiwei Yin
Keyword(s):  
N Mineralization ◽  
Regional Scale ◽  
Mineral Soil ◽  
Published Data ◽  
N Availability ◽  
Net N Mineralization ◽  
Soil N ◽  
Litter Fall ◽  
Available N ◽  
N Pool

Published data were analyzed to examine whether nitrogen (N) availability varies along macroclimatic gradients in North America. Extractable N produced during 8-week aerobic laboratory incubation was used as an index of potential net N mineralization. Mean extractable N during the growing season in the forest floor plus top mineral soil was used as an index of the available N pool. Using multiple regression, potential net N mineralization was shown to increase with available N and with litter-fall N (R2 = 0.722). Available N increased with increasing total soil N and with decreasing mean January and July air temperatures (R2 = 0.770). These relationships appeared to hold also for deciduous and coniferous forests separately across regions. Results suggest that net N mineralization output under uniform temperature and moisture conditions can be generally expressed by variations of N input (litter fall) and the available soil N pool, and that the available soil N pool is predictable along a temperature gradient at a regional scale.

Evaluation of three insitu soil nitrogen availability assays

1989 ◽  
Vol 19 (2) ◽  
pp. 185-191 ◽  
Author(s):  
Stephen C. Hart ◽  
Mary K. Firestone
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Soil Water Content ◽  
Nitrogen Availability ◽  
Mineral Soil ◽  
N Availability ◽  
Net N Mineralization ◽  
Old Growth ◽  
The Core ◽  
Young Growth

Three indices of nitrogen (N) availability were compared in the field over a 1-year period in an old-growth and a young-growth mixed-conifer forest. The indices utilized were ion exchange resin (IER) bags, buried bags, and a core-IER method employing intact soil cores enclosed in tubes capped at both ends by IER bags. The results from all three methods indicated that in the surface mineral soil, N availability was higher in the young-growth stand than in the old-growth stand. However, seasonal patterns of N availability were generally not well correlated among the methods (correlation coefficients ranged from 0.32 to 0.62). For a given amount of net N mineralized in buried bags, more N accumulated on IER bags placed in the young-growth stand than in those placed in the old-growth stand. This was the result of greater net nitrification in the young-growth stand coupled with the greater mobility of [Formula: see text] relative to [Formula: see text] in soil. Ten-month estimates of net N mineralization measured by the core-IER and buried-bag methods were similar in the young-growth stand (about 42 mg•kg soil−1), but the core-IER estimate was almost twice that of the buried-bag estimate in the old-growth stand (31.7 and 16.8 mg•kg soil−1, respectively). The different sensitivities of the core-IER and buried-bag methods to changes in soil moisture and leaching probably account for much of the difference in their N availability estimates. Results from the core-IER method did reflect the effects of leaching; however, soil water content within the core did not follow changes in soil water content effectively. Because of the greater labor involved in using the core-IER method, its use may be most efficacious in high-precipitation environments, or when in-field soil incubations must be conducted for extended periods of time.

Nitrogen mineralization and nitrification in successional ecosystems on the Tanana River floodplain, interior Alaska

1993 ◽  
Vol 23 (5) ◽  
pp. 970-978 ◽  
Author(s):  
K. Van Cleve ◽  
J. Yarie ◽  
R. Erickson ◽  
C.T. Dyrness
Keyword(s):  
Soil Temperature ◽  
Nitrogen Mineralization ◽  
N Mineralization ◽  
Vegetation Type ◽  
Mineral Soil ◽  
Net N Mineralization ◽  
Litter Layer ◽  
River Floodplain ◽  
Interior Alaska ◽  
Forest Floors

Nitrogen (N) mineralization and nitrification were compared among ecosystems representing a primary successional sequence on the Tanana River floodplain of interior Alaska. These processes displayed marked seasonality, were closely related to substrate chemistry, and reflected the impact of vegetation clearing. The highest rates of N mineralization were encountered in the June to July incubation periods, and rates generally declined during the remainder of the summer. The early season period (June to July) was the interval of most favorable litter and mineral soil temperature and most available energy supply for microbial mineralization of detrital materials. Minimal rates were encountered during the winter. Litter layer N mineralization rates were highest in the early-successional poplar–alder (Populusbalsamifera–Alnustenuifolia (Nutt.) stage and declined with advancing succession in poplar (Populusbalsamifera) and mature white spruce (Piceaglauca) (Moench) Voss) stands. The poplar–alder stage displayed the highest rate of nitrification. Nitrate constituted 98% of the mineralized N in early-successional poplar–alder forest floors but fell to 4 and 0% in poplar and white spruce forest floors, respectively. Nitrogen mineralization was closely related to significant increases in the lignin/N ratio across the sequence of vegetation types. The rate of surface mineral soil net N mineralization increased with succession in response to higher soil organic matter content. The range of average total seasonal net N mineralization (260–1600 mg N•m−2) for litter layer plus mineral soil among successional stages in this study was generally lower than the 1200–8400 mg N•m−2 reported by investigators for other studies in temperate latitudes. Vegetation clearing increased the magnitude of temporal fluxes as well as total annual mineral N production. The most consistent increases were encountered in the poplar–alder vegetation type. The average seasonal total net N mineralization for forest floor plus mineral soil in this vegetation type increased from 1500 to 3264 mg N•m−2 as a result of clearing. Soil temperature declined with advancing succession and generally increased as a consequence of clearing. However, these changes were not as closely correlated with N mineralization as were the changes in substrate chemistry encountered across this successional sequence.

Trophic structure of nematode communities, microbial biomass, and nitrogen mineralization in soils of forests and clearcuts in the southern interior of British Columbia

2000 ◽  
Vol 80 (3) ◽  
pp. 401-410 ◽  
Author(s):  
T. A. Forge ◽  
S. W. Simard
Keyword(s):  
British Columbia ◽  
Microbial Biomass ◽  
Forest Soil ◽  
Nitrogen Mineralization ◽  
N Mineralization ◽  
Trophic Structure ◽  
Mineral Soil ◽  
Bacterial Biomass ◽  
Net N Mineralization ◽  
Nematode Communities

The trophic structure of nematode communities, lengths of fungal hyphae, and gross populations of protozoa and bacteria were compared between clearcuts and adjacent forests at three sites in the southern interior of British Columbia in 1996, 1997, and 1998. Total C and N, mineralizable N (anaerobic incubation), and N mineralised during aerobic incubations, were determined from the same soil samples used for biological assays. Net N mineralization did not differ between clearcuts and forests in 1997; in 1998 net N mineralization in the organic horizon was four times greater for forests than for clearcuts. Hyphal lengths and total microbial biomass were greater in forest soil than in clearcut soil. Bacterial abundance was greater in forest soil than in clearcut soil in 1996 only. The abundance of protozoa did not differ between clearcuts and forests. Fungivorous, omnivorous, and predacious nematodes were less abundant in clearcut soil than in forest soil. Bacterivorous nematodes were more abundant in the mineral soil of clearcuts than in forests in 1996, but did not differ between clearcuts and forests in any other combination of year and horizon. Net N mineralization was correlated with the ratio of bacterial biomass/fungal biomass (r = 0.72, 12 degrees of freedom), as well as the abundance of amoebae (r = 0.83), total nematodes (r = 0.80), bacterivorous nematodes (r = 0.74), and fungivorous nematodes (r = 0.83). Key words: Microfauna, nematode ecology, microbial biomass, clearcut harvesting, nitrogen mineralization

scholarly journals The greenhouse gas exchange responses of methane and nitrous oxide to forest change in Europe

2012 ◽  
Vol 9 (5) ◽  
pp. 6129-6168 ◽  
Author(s):  
P. Gundersen ◽  
J. R. Christiansen ◽  
G. Alberti ◽  
N. Brüggemann ◽  
S. Castaldi ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Greenhouse Gas ◽  
Mineral Soil ◽  
Wood Ash ◽  
Soil Conditions ◽  
N2o Emissions ◽  
N Availability ◽  
Forest Change ◽  
Soil C ◽  
High Soil

Abstract. Climate change and air pollution, interact with altering forest management and land-use change to produce short and long-term changes to forest in Europe. The impact of these changes on the forest greenhouse gas (GHG) balance is currently difficult to predict. To improve the mechanistic understanding of the ongoing changes, we studied the response of GHG (N2O, CH4) exchange from forest soils at twelve experimental or natural gradient forest sites, representing anticipated future forest change. The experimental manipulations one or more per site included nitrogen (N) addition (4 sites), changes of climate (temperature, 1 site; precipitation, 2 sites), soil hydrology (3 sites), harvest intensity (1 site), wood ash fertilization (1 site), pH gradient in peat (1 site) and afforestation of cropland (1 site). In most of the investigated treatments N2O emissions increased by 7 ± 3 (range 0–30) μg N2O-N m−2 h−1 across all treatments on mineral soils, but by up to 10 times the mineral soil maximum on an acidic organic soil. Soil moisture together with mineral soil C/N ratio and pH were found to significantly influence N2O emissions across all treatments. Emissions increased with N availability and decreased with soil C/N ratio, especially in interaction with increased soil moisture. High pH reduced the formation of N2O, even under otherwise favourable soil conditions. Oxidation (uptake) of CH4 was reduced from 16 ± 2 to 4 ± 6 μg CH4-C m−2 h−1 by the investigated treatments. The CH4 exchange was significantly influenced by soil moisture and soil C/N ratio across all treatments, and CH4 emissions occurred only in wet or water-saturated conditions. For most of the investigated forest manipulations or natural gradients, the response of both N2O and CH4 fluxes was towards reducing the overall GHG forest sink. The most resilient forests were dry Mediterranean forests, as well as forests with high soil C/N ratio or high soil pH. Mitigation strategies may focus on (i) sustainable management of wet forest areas and forested peat lands, (ii) continuous forest cover management, (iii) reducing atmospheric N input and, thus, N availability, and (iv) improving neutralisation capacity of acid soils (e.g. wood ash application).

Nitrogen availability in soil and forest floor of contrasting types of boreal mixedwood forests

2006 ◽  
Vol 36 (1) ◽  
pp. 112-122 ◽  
Author(s):  
Lucie Jerabkova ◽  
Cindy E Prescott ◽  
Barbara E Kishchuk
Keyword(s):  
Boreal Forests ◽  
Forest Floor ◽  
Nitrogen Availability ◽  
Mineral Soil ◽  
N Availability ◽  
Net N Mineralization ◽  
Deciduous Species ◽  
Mixed Stands ◽  
Mixedwood Forests ◽  
The North

Boreal mixedwood forests with varying proportions of coniferous and deciduous species are found throughout the North American continent. Maintenance of a deciduous component within boreal forests is currently favoured, as deciduous species are believed to promote faster nutrient turnover and higher nutrient availability. Results of comparisons of deciduous and coniferous forests are, however, inconsistent in supporting this generalization. We compared indices of soil nitrogen (N) availability in the forest floor and mineral soil of deciduous, mixed, and coniferous stands of boreal mixedwood forest in northwestern Alberta. Deciduous stands had higher N availability, reflected by higher pools of NH4-N and inorganic N in the forest floor. Forest floors of deciduous stands also tended to have higher concentrations of microbial N but did not have higher levels of NO3-N or higher rates of net nitrification. Mixed stands showed the highest rates of net N mineralization. Soil N availability was more closely related to litter N content than to litter decomposition rate. The variation among the forest types is likely attributable to vegetation, as topography is fairly uniform, stands do not differ in soil texture, and N-availability indices correlated directly with the proportion of deciduous trees.

Sign in / Sign up

Export Citation Format

Share Document