Initial quantitative characterization of soil nutrient regimes. I. Soil properties

1987 ◽  
Vol 17 (12) ◽  
pp. 1557-1564 ◽  
Author(s):  
R. D. Kabzems ◽  
K. Klinka

Previous attempts to characterize soil nutrient regimes of forest ecosystems have been qualitative evaluations utilizing vegetation and (or) topographic features, morphological soil properties, and mineralogy of soil parent materials. The objective of this study was to describe and provide initial data for quantitative classification of soil nutrient regimes in some Douglas-fir ecosystems on southern Vancouver Island. A multivariate classification using forest floor plus mineral soil mineralizable N and exchangeable Mg quantities was proposed for the four nutrient regimes (poor, medium, rich, and very rich) recognized in this study. Significant differences in mineralizable and total N existed between the four identified soil nutrient regimes. The previous N fertilization of two study sites did not seem to change soil N status sufficiently to alter the classification. The differences in nutrient availability were more distinct when forest floor and mineral soil properties, expressed on an areal basis, were summed. There were no significant differences in exchangeable Ca and Mg for the poor and medium soil nutrient regimes. The humus form of the forest floor was an important characteristic for identifying soil nutrient regimes in the field; however, the nutrient quantities of the forest floor reflected differences in bulk density and depth and did not effectively distinguish between regimes.

1984 ◽  
Vol 14 (2) ◽  
pp. 155-162 ◽  
Author(s):  
M. A. Radwan ◽  
D. S. DeBell ◽  
S. R. Webster ◽  
S. P. Gessel

Effects of different sources of fertilizer N on selected chemical characteristics of soils and foliage, and on growth of western hemlock (Tsugaheterophylla (Raf.) Sarg.) were compared at three different sites in western Washington. Treatments were the following: untreated control (O), ammonium nitrate (AN), ammonium sulfate (AS), calcium nitrate (CN), urea (U), and urea – ammonium sulfate (US). Fertilizers were applied in the spring (April–May) at 224 kg N/ha. Forest floor and mineral soil, to a depth of 5 cm, and foliage were sampled periodically for 2 years. Height and diameter of selected trees were measured periodically for 4 years. Results are reported mostly for two sites, one in the Cascade Range and one in the coastal zone in western Washington. The pH of forest floor and mineral soil varied by treatment, and the two urea fertilizers caused substantial initial rise. Effects on soil and foliar nutrients varied by fertilizer, sampling date, and location. In general, all fertilizers increased NH4 N, N03 N, and total N in the forest floor and mineral soil, and total N in the foliage. Also, with some exceptions, especially with foliar P in the Cascade site, fertilization reduced foliar content of important nutrients. At the Cascade site, 4-year growth responses in height, basal area, and volume averaged over all fertilizers were 30, 34, and 32%, respectively. AN, AS, CN, and urea resulted in height growth significantly (P < 0.20) higher than that of the control. Significant basal area growth and volume-growth responses were produced by AN, CN, and US. No significant height-growth response to any fertilizer occurred in the coastal stand; basal area growth and volume-growth responses averaged 27 and 21%, respectively, and best response occurred with urea. These results suggest that the low and inconsistent response of hemlock to N fertilization cannot be improved by applying some N fertilizer other than urea. Factors limiting response to N fertilization may be associated with availability of native N and other nutrients or other characteristics of hemlock sites and stands.


2014 ◽  
Vol 94 (3) ◽  
pp. 263-279 ◽  
Author(s):  
Barbara E. Kishchuk ◽  
Sylvie Quideau ◽  
Yonghe Wang ◽  
Cindy Prescott

Kishchuk, B. E., Quideau, S., Wang, Y. and Prescott, C. 2014. Long-term soil response to variable-retention harvesting in the EMEND (Ecosystem Management Emulating Natural Disturbance) experiment, northwestern Alberta. Can. J. Soil Sci. 94: 263–279. We report on soil responses to variable-retention (VR) harvesting from a large-scale experiment (>1000 ha). Samples were taken prior to treatment, and 1 and 6 yr after treatment under cover types representing the successional trajectory for boreal mixedwood forests in northwestern Alberta, Canada. Variable-retention harvesting at six overstory-retention levels [100 (control), 75, 50, 20, 10, and 0% (clearcut)] were applied to 10-ha experimental units under four cover types: deciduous-dominated (80–95% trembling aspen); deciduous-dominated with coniferous understory (80–95% trembling aspen with white spruce understory at 60–80% of full stocking); mixed coniferous-deciduous (35–65% of each); and coniferous-dominated (80–95% white spruce). Only a few clear differences in soil properties attributable to VR harvesting were evident 6 yr post-harvest: (1) both extractable NH4-N in forest floor and 0–7 cm mineral-soil, and forest floor exchangeable K decreased with increasing canopy removal, and (2) forest floor exchangeable Ca increased with canopy removal. There was a decreasing trend in forest floor and mineral soil C (kg ha−1) in undisturbed stands between 1998 and 2005. Differences in soil properties among cover types included higher pH and N concentration in forest floors, and higher cation exchange capacity and exchangeable Ca and Mg in mineral soils in deciduous-dominated stands. Deciduous-dominated stands appear to have distinct soil properties that change under stand development.


2001 ◽  
Vol 31 (5) ◽  
pp. 889-898 ◽  
Author(s):  
J Clive Carlyle ◽  
EK Sadanandan Nambiar

We examined the relationship between net nitrogen (N) mineralization (subsequently termed N mineralization) in the forest floor and mineral soil (0–0.15 m) of 20 Pinus radiata D. Don plantations ranging in age from 23 to 59 years, how mineralization was influenced by soil properties, and its relationship to wood production. Forest floor properties had a narrower relative range than the same set of mineral soil properties. Total N in the litter layer was 5.0–9.5 g·kg–1 compared with 0.23–2.53 g·kg–1 in mineral soil. Laboratory rates of net N mineralization ranged between 1.1 and 9.7 mg·kg–1·day–1 in forest floor and between 0.02 and 0.53 mg·kg–1·day–1 in mineral soil. The range in litter lignin (35.3–48.0%) was especially narrow, despite the large range in stand productivity. Nitrogen mineralized in the forest floor was not correlated with any of the measured forest floor or mineral soil properties. Nitrogen mineralized per unit mineral soil N (ksn) was negatively correlated with the mineral soil N to organic phosphorus ratio (N/Po) (r2 = 0.82). In mineral soil a relationship combining N/Po and total N concentration explained 90% of the variation in N mineralized. Nitrogen mineralized in the forest floor was correlated with that mineralized in the mineral soil when expressed per unit C or N (r2 = 0.54 or 0.57, respectively). Thus, the quality of organic matter in the forest floor partly reflected the quality of organic matter in the mineral soil with respect to N mineralization. Mineralization in mineral soil dominated the net N available to the stand. For sandy soils, wood production (m3·ha–1·year–1) was correlated with N mineralized in the forest floor + mineral soil (r2 = 0.71). In P. radiata stands growing in southern Australia, rates of wood production per unit N mineralized and per unit rainfall appear to be substantially higher than those of a wide range of natural and planted stands in North America.


1994 ◽  
Vol 74 (1) ◽  
pp. 29-38 ◽  
Author(s):  
Karel Klinka ◽  
Gordon J. Kayahara ◽  
Qingli Wang

In order to assess to what extent soil nutrient properties support differentiation of field-identified soil nutrient regimes, composite samples from each forest floor and 0–30 cm of the mineral soil were collected from 116 forest stands in central British Columbia. The samples were analyzed for acidity, total carbon (tC), total nitrogen (tN), mineralizable-N (min-N), and extractable Ca, Mg, K, P, and SO4-S (eCa, eMg, eK, eP, eSO4); and the results were expressed as concentrations on a dry-mass basis. Mineralizable-N of the mineral soil showed (1) the largest amount of variation in the population of sampled soils, (2) significant differences (P < 0.01) among field-identified soil nutrient regimes, and (3) strong correlations with tC, tN, and eCa, eMg, and eK. Using mineral soil min-N as a differentiating characteristic, the following limiting values (mg kg−1) were proposed to provide an objective means of defining soil nutrient regimes: < 2 for very poor, 2–8.9 for poor, 9–27.4 for medium, 27.5–110 for rich, and > 110 for very rich. Site index (height at 50 yr breast height age) of lodge-pole pine (Pinus contorta Dougl. ex Loud) and interior spruce [Picea engelmannii Parry ex Engelmann × P. glauca (Moench) Voss] increased from very poor to very rich soils; however, the differences among site indices of contiguous soil nutrient regimes were largely insignificant. Regression analysis indicated that (1) soil moisture accounts for the largest proportion of the variation in site index, (2) models using C:N ratio of the forest floor and 0–30 cm of the mineral soil had a stronger relationship with site index (0.38 ≤ R2 ≤ 0.43, standard error < 3.0 m) than those using min-N. These results gave further evidence that min-N in the 0–30 mineral soil is a good single measure representing soil nutrient conditions, and justify the use of the existing field procedure for estimating soil nutrient regimes in montane boreal soils. Key words: Boreal soils, soil nutrient regime, quantitative classification, mineralizable-N, site index


1995 ◽  
Vol 75 (3) ◽  
pp. 343-348 ◽  
Author(s):  
Christian Godbout ◽  
Jean-Louis Brown

A Podzolic soil from an old-growth maple hardwood forest in eastern Canada was systematically sampled from a 16.5-m-long trench in 1975. In 1986, the upper 10 cm of the B horizon was resampled from two sampling lines located on each side and parallel to the 1975 trench, one at a distance of 1 m downhill and the other at a distance of 4 m uphill. Total N, organic C, pH, and exchangeable Ca, Mg and K were measured. The objectives were to evaluate the change in the chemical status of the B horizon from 1975 to 1986 and to characterize the spatial variability of the horizon. No significant change was found in the soil chemical properties tested during this 11-yr period. No significant autocorrelation was observed between soil samples 60 cm apart, except for the downhill sampling line, which was located 1 m from the trench. For most properties, the magnitude of the difference between two soil sampling units was not proportional to the distance separating them over the range of 0.6–4.2 m. Except for pH, a difference in soil properties of more than 30% was observed in 37–56% of sample pairs 60 cm apart. Resampling near (1 m) an old soil pit may not be valid because of possible local modifications of soil properties created by the pit, even when it is filled in. Key words: Podzol, soil variability, acidic deposition, soil changes


Forests ◽  
2019 ◽  
Vol 10 (4) ◽  
pp. 351
Author(s):  
Aiguo Duan ◽  
Jie Lei ◽  
Xiaoyan Hu ◽  
Jianguo Zhang ◽  
Hailun Du ◽  
...  

Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) is a fast-growing evergreen conifer with high-quality timber and is an important reforestation and commercial tree species in southern China. Planting density affects the productivity of Chinese fir plantations. To study the effect of five different planting densities and soil depth on soil nutrient contents of a mature C. lanceolata plantation, the soil nutrient contents (soil depths 0–100 cm) of 36-year-old mature Chinese fir plantations under five different planting densities denoted A (1667 trees·ha−1), B (3333 trees·ha−1), C (5000 trees·ha−1), D (6667 trees·ha−1), and E (10,000 trees·ha−1) were measured in Pingxiang county, Guangxi province, China. Samples were collected from the soil surface down to a one meter depth from each of 45 soil profiles, and soil samples were obtained at 10 different soil depths of 0–10, 10–20, 20–30, 30–40, 40–50, 50–60, 60–70, 70–80, 80–90, and 90–100 cm. Twelve soil physical and chemical indicators were analyzed. The results showed that: (1) as planting density increased, the organic matter, organic carbon, total N and P, available N, effective Fe, and bulk density decreased. Soil pH, total K, and effective K increased with increasing planting density. Planting density did not significantly influence the exchangeable Ca and Mg. (2) Soil organic matter; organic carbon; total N and P; effective N, P, and K; exchangeable Ca and Mg; effective Fe content; and bulk density decreased with increasing soil depth. This pattern was particularly evident in the top 30 cm of the soil. (3) Excessively high planting density is not beneficial to the long-term maintenance of soil fertility in Chinese fir plantations, and the planting density of Chinese fir plantations should be maintained below 3333 stems·ha−1 (density A or B) to maintain soil fertility while ensuring high yields.


2012 ◽  
Vol 88 (03) ◽  
pp. 306-316 ◽  
Author(s):  
Richard Kabzems

Declines in forest productivity have been linked to losses of organic matter and soil porosity. To assess how removal of organic matter and soil compaction affect short-term ecosystem dynamics, pre-treatment and year 1, 5 and 10 post-treatment soil properties and post-treatment plant community responses were examined in a boreal trembling aspen (Populus tremuloidesMichx.)-dominated ecosystem in northeastern British Columbia. The experiment used a completely randomized design with three levels of organic matter removal (tree stems only; stems and slash; stems, slash and forest floor) and three levels of soil compaction (none, intermediate [2-cm impression], heavy [5-cm impression]). Removal of the forest floor initially stimulated aspen regeneration and significantly reduced height growth of aspen (198 cm compared to 472–480 cm) as well as white spruce (Picea glauca [Moench] Voss) height (82 cm compared to 154–156 cm). The compaction treatments had no effect on aspen regeneration density. At Year 10, heights of both aspen and white spruce were negatively correlated with upper mineral soil bulk density and were lowest on forest floor + whole tree removal treatments. Recovery of soil properties was occurring in the 0 cm to 2 cm layer of mineral soil. Bulk density values for the 0 cm to 10 cm depth remained above 86% of the maximum bulk density for the site, a soil condition where reduced tree growth can be expected.


1987 ◽  
Vol 17 (12) ◽  
pp. 1565-1571 ◽  
Author(s):  
R. D. Kabzems ◽  
K. Klinka

Relationships between soil properties, understory vegetation, foliar properties, and site index were examined in some Douglas-fir ecosystems on Vancouver Island. Multivariate summaries of variation in understory vegetation and foliar properties were highly correlated with the soil properties (mineralizable N, total N, and exchangeable Ca and Mg) that best characterized soil nutrient regimes of the ecosystems. The increases in soil nutrient availability were correlated with increased foliar N concentrations of the current year foliage. A consistent correlation was found between increased soil nutrient availability (particularly N, Mg, Ca) and decreased foliar Mn and Al. Site index of Douglas-fir was significantly greater on sites with greater quantities of most nutrients (particularly N, Mg, Ca) when sites with equivalent soil moisture regime were compared.


1986 ◽  
Vol 16 (4) ◽  
pp. 872-874 ◽  
Author(s):  
O. Q. Hendrickson

Three years after harvesting a mixed conifer–hardwood forest in Ontario, the density of sweet fern (Comptoniaperegrina (L.) Coult.) was far greater on a whole-tree harvest site (logging slash removed) than on an adjacent conventional harvest site (logging slash present). These differences were related to the degree of site disturbance, particularly forest floor removal. Nodule fixation rates also appeared to reflect the degree of disturbance, being highest in plants growing along a logging road where the sandy, nitrogen-poor mineral soil was exposed, and exceptionally low on the conventional harvest site (0.67 μmol C2H4 g dry weight−1 h−1). Overall, acetylene reduction activity showed a significant negative correlation (r = −0.77, p < 0.001) with total N.


2011 ◽  
Vol 41 (1) ◽  
pp. 195-210 ◽  
Author(s):  
Alison Cross ◽  
Steven S. Perakis

Old-growth forests of the Pacific Northwest provide a unique opportunity to examine tree species – soil relationships in ecosystems that have developed without significant human disturbance. We characterized foliage, forest floor, and mineral soil nutrients associated with four canopy tree species (Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco), western hemlock (Tsuga heterophylla (Raf.) Sarg.), western redcedar (Thuja plicata Donn ex D. Don), and bigleaf maple (Acer macrophyllum Pursh)) in eight old-growth forests of the Oregon Coast Range. The greatest forest floor accumulations of C, N, P, Ca, Mg, and K occurred under Douglas-fir, primarily due to greater forest floor mass. In mineral soil, western hemlock exhibited significantly lower Ca concentration and sum of cations (Ca + Mg + K) than bigleaf maple, with intermediate values for Douglas-fir and western redcedar. Bigleaf maple explained most species-based differences in foliar nutrients, displaying high concentrations of N, P, Ca, Mg, and K. Foliar P and N:P variations largely reflected soil P variation across sites. The four tree species that we examined exhibited a number of individualistic effects on soil nutrient levels that contribute to biogeochemical heterogeneity in these ecosystems. Where fire suppression and long-term succession favor dominance by highly shade-tolerant western hemlock, our results suggest a potential for declines in both soil Ca availability and soil biogeochemical heterogeneity in old-growth forests.


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