Decomposition rates and nutrient dynamics of Picea abies needles, twigs and fine roots after stem-only harvesting in eastern and western Norway

Interspecific comparisons of the fine root “behaviour” under stressful situations may answer questions related to resistance to changing environmental conditions in the particular tree species. Our study was focused on Norway spruce (<I>Picea abies</I> [L.] Karst.) and European beech (<I>Fagus sylvatica</I> L.) grown in an acidic soil where acidity was caused by past air pollution in the Kysucké Beskydy Mts., North-Western Slovakia. Between April and October 2006, the following fine root traits were studied: biomass and necromass seasonal dynamics, vertical distribution, production, mortality, fine root turnover and production to mortality ratio. Sequential soil coring was repeatedly implemented in April, June, July, September, and October including the soil layers of 0–5, 5–15, 15–25, and 25–35 cm. Results indicated that spruce had a lower standing stock of fine roots than beech, and fine roots of spruce were more superficially distributed than those of beech. Furthermore, we estimated higher seasonal dynamics and also higher turnover of fine roots in spruce than in beech. The production to mortality ratio was higher in beech than in spruce, which was hypothetically explained as the effect of drought episodes that occurred in July and August. The results suggested that the beech root system could resist a physiological stress better than that of spruce. This conclusion was supported by different vertical distributions of fine roots in spruce and beech stands.

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Effect of Altitude on Nutrient Concentration, Nutrient Stock and Uptake in Fine Root of Sal (Shorea Robusta Gaertn.) Forest in Terai and Hill Areas of Eastern Nepal

Journal of Institute of Science and Technology ◽

10.3126/jist.v25i1.29420 ◽

2020 ◽

Vol 25 (1) ◽

pp. 24-29

Author(s):

Krishna Prasad Bhattarai ◽

Tej Narayan Mandal ◽

Tilak Prasad Gautam

Keyword(s):

Fine Roots ◽

Root Biomass ◽

Nutrient Concentration ◽

Nutrient Dynamics ◽

Fine Root ◽

Soil Depth ◽

Fine Root Biomass ◽

Root Production ◽

Nutrient Stock ◽

Sal Forest

The present study was conducted to understand the effect of altitude on the nutrient concentration, nutrient stock, and uptake in the fine root of the Terai Sal forest (TSF) and Hill Sal forest (HSF) in eastern Nepal. Annual mean fine root biomass in 0-30 cm soil depth was found higher in HSF (6.27 Mg ha-1) than TSF (5.05 Mg ha-1). Conversely, fine root production was higher in TSF (4.8 Mg ha-1 y-1) than HSF (4.12 Mg ha-1 y-1). Nitrogen, phosphorus, and potassium content in fine roots were slightly higher in TSF than HSF. Nutrient concentration in fine roots of smaller size (<2 mm diameter) was nearly 1.2 times greater than that of larger size (2–5 mm diameter) in both forests. In HSF total stock of different nutrients (kg ha-1) in fine root was 55.62 N, 4.99 P, and 20.15 K whereas, these values were 49.49 N, 4.14 P, and 19.27 K only in TSF. However, total nutrient uptake (kg ha-1y-1) by fine root (both size classes) was greater in TSF (48.5 N, 4.3 P, and 18.6 K) than HSF (36.9 N, 3.3 P, and 13.5 K). The variability in fine root nutrient dynamics between these two forests was explained by the differences in fine root biomass and production which were influenced by the combined effect of varied altitude and season. The fine root, as being a greater source of organic matter, the information on its nutrient dynamics is inevitable for the management of soil nutrients in the forest ecosystem.

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Decomposition and nutrient release from green needles of western hemlock and Pacific silver fir in an old-growth temperate rain forest9 Olympic National Park, Washington

Canadian Journal of Forest Research ◽

10.1139/x95-115 ◽

1995 ◽

Vol 25 (7) ◽

pp. 1049-1057 ◽

Cited By ~ 20

Author(s):

Robert L. Edmonds ◽

Ted B. Thomas

Keyword(s):

Mass Loss ◽

National Park ◽

Nutrient Dynamics ◽

Western Hemlock ◽

Dominant Factor ◽

Silver Fir ◽

Decomposition Rates ◽

Old Growth ◽

Olympic National Park ◽

Significant Difference

Decomposition rates and nutrient dynamics (for N, P, K, Ca, Mg, Mn, and Na) were determined for green needles of western hemlock (Tsugaheterophylla (Raf.) Sarg.) and Pacific silver fir (Abiesamabilis (Dougl.) Forb.) in an old-growth forested watershed (58 ha West Twin Creek) in the Hoh River valley, Olympic National Park, Washington. The influence of temperature and substrate chemistry on decomposition was determined. Temperature was the dominant factor controlling decomposition rates in the first year in this watershed, with the fastest decomposition at an elevation of 275 m (lower watershed) and the slowest decomposition at 725 m (upper watershed). After 12 months mass loss averaged 36% in the lower watershed and 28% in the upper watershed. There was no significant difference in decomposition rates between species. Substrate chemistry, i.e., the lignin/N ratio, became a more important factor than temperature as decomposition proceeded. After 37 months mass loss for needles averaged 61% for western hemlock and 50% for Pacific silver fir, with no difference by watershed location. After 61 months both types of substrates appeared to be approaching similar substrate chemistry and similar decomposition rates and there were no significant differences by species or watershed location. Decomposition constants (k values) after 61 months were 0.26 and 0.20 year−1 for western hemlock needles in the lower and upper watershed, respectively, and 0.22 and 0.19 year−1 for Pacific silver fir needles in the lower and upper watershed, respectively. Nitrogen was immobilized during the first 12 months of decomposition in needles of both species and then released. No other elements were immobilized during the initial (0- to 12-month) decomposition period, except for Ca in Pacific silver fir needles. However, in the 37- to 61-month period there was a considerable immobilization of Mg and Na in both species in the upper and lower watershed and K and Mn in both species in the upper watershed.

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Decomposition rates of fine roots from three herbaceous perennial species: combined effect of root mixture composition and living plant community

Plant and Soil ◽

10.1007/s11104-016-3163-z ◽

2017 ◽

Vol 415 (1-2) ◽

pp. 359-372 ◽

Cited By ~ 11

Author(s):

Iván Prieto ◽

Marine Birouste ◽

Ezequiel Zamora-Ledezma ◽

Anaïs Gentit ◽

Jeanne Goldin ◽

...

Keyword(s):

Plant Community ◽

Fine Roots ◽

Combined Effect ◽

Mixture Composition ◽

Perennial Species ◽

Decomposition Rates ◽

Living Plant ◽

Herbaceous Perennial

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Soil CO2 evolution in Florida slash pine plantations. II. Importance of root respiration

Canadian Journal of Forest Research ◽

10.1139/x87-055 ◽

1987 ◽

Vol 17 (4) ◽

pp. 330-333 ◽

Cited By ~ 131

Author(s):

Katherine C. Ewel ◽

Wendell P. Cropper.Jr. ◽

Henry L. Gholz

Keyword(s):

Fine Roots ◽

Root Biomass ◽

Root Respiration ◽

Slash Pine ◽

Co2 Evolution ◽

Soil Co2 ◽

Decomposition Rates ◽

Subsequent Decomposition ◽

Initial Root ◽

Soil Co2 Evolution

Respiration of live roots was the single largest contributor to soil CO2 evolution in two mature slash pine (Pinuselliottii) plantations. Root respiration accounted for 51% of soil CO2 evolution at the 9-year-old plantation and 62% at the 29-year-old plantation. Additional estimates, calculated from data recorded from two small trenched plot sites at the 29-year-old plantation and based on possible variations in initial root biomass and subsequent decomposition rates, also averaged 62% of soil CO2 evolution. Specific root respiration averaged 0.40 g•g−1•year−1, varying from 0.34 to 1.70 g•g−1•year−1. Plots with larger proportions of fine roots had faster soil CO2 evolution rates.

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Limited Effects of Variable-Retention Harvesting on Fungal Communities Decomposing Fine Roots in Coastal Temperate Rainforests

Applied and Environmental Microbiology ◽

10.1128/aem.02061-17 ◽

2017 ◽

Vol 84 (3) ◽

Cited By ~ 2

Author(s):

Timothy J. Philpott ◽

Jason S. Barker ◽

Cindy E. Prescott ◽

Sue J. Grayston

Keyword(s):

Community Composition ◽

Fungal Community ◽

Fine Roots ◽

Fine Root ◽

Plant Litter ◽

Fungal Communities ◽

Decomposition Rates ◽

Fungal Community Composition ◽

Variable Retention ◽

Variable Retention Harvesting

ABSTRACT Fine root litter is the principal source of carbon stored in forest soils and a dominant source of carbon for fungal decomposers. Differences in decomposer capacity between fungal species may be important determinants of fine-root decomposition rates. Variable-retention harvesting (VRH) provides refuge for ectomycorrhizal fungi, but its influence on fine-root decomposers is unknown, as are the effects of functional shifts in these fungal communities on carbon cycling. We compared fungal communities decomposing fine roots (in litter bags) under VRH, clear-cut, and uncut stands at two sites (6 and 13 years postharvest) and two decay stages (43 days and 1 year after burial) in Douglas fir forests in coastal British Columbia, Canada. Fungal species and guilds were identified from decomposed fine roots using high-throughput sequencing. Variable retention had short-term effects on β-diversity; harvest treatment modified the fungal community composition at the 6-year-postharvest site, but not at the 13-year-postharvest site. Ericoid and ectomycorrhizal guilds were not more abundant under VRH, but stand age significantly structured species composition. Guild composition varied by decay stage, with ruderal species later replaced by saprotrophs and ectomycorrhizae. Ectomycorrhizal abundance on decomposing fine roots may partially explain why fine roots typically decompose more slowly than surface litter. Our results indicate that stand age structures fine-root decomposers but that decay stage is more important in structuring the fungal community than shifts caused by harvesting. The rapid postharvest recovery of fungal communities decomposing fine roots suggests resiliency within this community, at least in these young regenerating stands in coastal British Columbia. IMPORTANCE Globally, fine roots are a dominant source of carbon in forest soils, yet the fungi that decompose this material and that drive the sequestration or respiration of this carbon remain largely uncharacterized. Fungi vary in their capacity to decompose plant litter, suggesting that fungal community composition is an important determinant of decomposition rates. Variable-retention harvesting is a forestry practice that modifies fungal communities by providing refuge for ectomycorrhizal fungi. We evaluated the effects of variable retention and clear-cut harvesting on fungal communities decomposing fine roots at two sites (6 and 13 years postharvest), at two decay stages (43 days and 1 year), and in uncut stands in temperate rainforests. Harvesting impacts on fungal community composition were detected only after 6 years after harvest. We suggest that fungal community composition may be an important factor that reduces fine-root decomposition rates relative to those of above-ground plant litter, which has important consequences for forest carbon cycling.

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Nutrient dynamics in decomposing litter from four selected tree species in Makurdi, Benue State, Nigeria

Journal of Ecology and Environment ◽

10.1186/s41610-019-0139-y ◽

2019 ◽

Vol 43 (1) ◽

Author(s):

Thomas Okoh ◽

Esther Edu

Keyword(s):

Exposure Time ◽

Decomposition Rate ◽

Nutrient Dynamics ◽

Nutrient Release ◽

Wet Season ◽

Decomposition Rates ◽

Average Mass ◽

Accumulation Index ◽

Carbon Retention ◽

Vitex Doniana

Abstract Background Nutrient release during litter decomposition was investigated in Vitex doniana, Terminalia avecinioides, Sarcocephallus latifolius, and Parinari curatellifolius in Makurdi, Benue State Nigeria (January 10 to March 10 and from June 10 to August 10, 2016). Leaf decomposition was measured as loss in mass of litter over time using the decay model Wt/W0 = e−kd t, while $$ \mathrm{Kd}=-\frac{1}{t} In\left(\frac{Wt}{W0}\right) $$Kd=−1tInWtW0 was used to evaluate decomposition rate. Time taken for half of litter to decompose was measured using T50 = ln 2/k; while nutrient accumulation index was evaluated as NAI =$$ \left(\frac{\omega t\ Xt}{\omega \mathrm{o}X\mathrm{o}}\right). $$ωtXtωoXo. Results Average mass of litter remaining after exposure ranged from 96.15 g, (V. doniana) to 78.11 g, (S. lafolius) in dry (November to March) and wet (April to October) seasons. Decomposition rate was averagely faster in the wet season (0.0030) than in the dry season (0.0022) with P. curatellifolius (0.0028) and T. avecinioides (0.0039) having the fastest decomposition rates in dry and wet seasons. Mean residence time (days) ranged from 929 to 356, while the time (days) for half the original mass to decompose ranged from 622 to 201 (dry and wet seasons). ANOVA revealed highly significant differences (p < 0.01) in decomposition rates and exposure time (days) and a significant interaction (p < 0.05) between species and exposure time in both seasons. Conclusion Slow decomposition in the plant leaves implied carbon retention in the ecosystem and slow release of CO2 back to the atmosphere, while nitrogen was mineralized in both seasons. The plants therefore showed effectiveness in nutrient cycling and support productivity in the ecosystem.

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