Fine root production and nutrient dynamics in relation to stand characteristics of chir pine mixed banj oak forests in central Himalaya

This study reports on an investigation of fine root and foliage productivity in forest stands dominated by European beech (Fagus sylvatica L.) and exposed to contrasting intensities of mature forest harvesting. The main aim of this study was to consider the long-term effects of canopy manipulation on resource acquisition biomass compartments in beech. We made use of an experiment established in 1989, when five different light availability treatments were started in plots within a uniform forest stand, ranging from no reduction in tree density to full mature forest removal. We measured fine root standing stock in the 0–30 cm soil layer by coring in 2013 and then followed annual fine root production (in-growth cores) and foliage production (litter baskets) in 2013–2015. We found that the plot where the tree density was reduced by 30% had the lowest foliage and the highest fine root production. In 2013, this plot had the highest fine root turnover rate (0.8 year−1), while this indicator of fine root dynamics was much lower in the other four treatments (around 0.3 year−1). We also found that the annual fine root production represented around two thirds of annual foliage growth on the mass basis in all treatments. While our findings support the maintenance of source and sink balance in woody plants, we also found a long-lasting effect of tree density manipulation on investment into resource acquisition compartments in beech forests.

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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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Analysis of some sources of error in methods used to determine fine root production in forest ecosystems: a simulation approach

Canadian Journal of Forest Research ◽

10.1139/x87-142 ◽

1987 ◽

Vol 17 (8) ◽

pp. 909-912 ◽

Cited By ~ 66

Author(s):

W. A. Kurz ◽

J. P. Kimmins

Keyword(s):

Root Biomass ◽

Fine Root ◽

Sampling Error ◽

Simulated Data ◽

Sampling Interval ◽

Fine Root Biomass ◽

Root Production ◽

Seasonal Patterns ◽

Fine Root Production ◽

True Value

Fine root production rates are most commonly calculated from periodic measurements of live and dead fine root biomass. The accuracy of production estimates based on this method is very sensitive to violations of the inherent assumptions, particularly the assumption that the processes of fine root production and mortality are temporally separate. A simple model was used to simulate data for a variety of seasonal patterns of live and dead fine root biomass. Fine root production and mortality rates were calculated from these simulated data using two different computational methods. Comparison of the calculated rates with the known rates (the rates used to generate the seasonal patterns) revealed that violations of the above assumptions can result in inaccurate rate estimates. When fine root production and mortality occur simultaneously within a sampling interval, the calculated production rate will greatly underestimate the true value. Additional error in the rate estimates may result from sampling error associated with the fine root biomass data. The model suggested that sampling error can cause either overestimation or underestimation of fine root production.

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