Investigation the volume and carbon content of woody debrisees in the Naw forests of Asalem

Document Type : Research Paper

Authors

1 Department of Forest Science and Engineering, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran.

2 Department of Forestry, Kha.C., Islamic Azad University, Khalkhal, Iran.

10.22059/jfwp.2026.408252.1382

Abstract

Introduction: Woody debris (coarse and fine woody debris) is a key component of forest ecosystems, playing an important role in carbon storage, nutrient cycling, and habitat provision. However, the effects of different forest management practices on the volume, decay dynamics, and carbon content of these stocks, particularly in the Hyrcanian forests of Iran, have rarely been investigated simultaneously and comparatively. This study aimed to assess and compare the volume, abundance, decay classes, biomass, and carbon content of fine woody debris (FWD: 2–10 cm diameter) and coarse woody debris (CWD: ≥10 cm diameter) in four stands with different management histories in the Nav Asalem forests of Gilan Province, northern Iran.
Method: Four forest stands were selected: (1) a shelterwood stand with 40 years since the last harvest, (2) a single-selection cutting stand with 10 years since the last harvest, (3) a single-selection cutting stand combined with salvage logging of windthrown trees, and (4) a conservation stand (no harvesting) as a control. Sampling was conducted using a systematic random grid of 100 × 100 m. Circular plots of 1000 m² were used for CWD, and concentric circular plots of 500 m² were used for FWD. For each sample plot, the diameter and length of each woody piece were measured, and its decay class (1 to 4) was recorded based on visual and tactile criteria. The volume of each piece was calculated using Huber's formula. To determine basic density, three wood samples per decay class per stand were collected, and their dry weight was determined after oven-drying at 105°C. Biomass was obtained by multiplying volume by basic density, and carbon content was estimated using a conversion factor of 0.5. Additionally, distance from the road, slope percentage, and a stand accessibility index were recorded.
Results: The frequency of fine woody debris (507 pieces per hectare) in the protected stand was significantly lower than that in the other stands. The frequency of coarse woody debris in the shelterwood and single-selection stands was significantly higher than that in the protected stand. The shelterwood and protected stands had the highest volumes of fine woody debris, with 4.61 and 4.47 m³ per hectare, respectively, while the protected stand had the highest volume of coarse woody debris, at 14.25 m³ per hectare. The protected stand exhibited the highest frequency of highly decayed woody debris (30.8%) and the lowest frequency of low-decay woody debris (15.5%). The shelterwood stand had the highest fine woody debris biomass (1062 kg per hectare), and the protected stand had the highest coarse woody debris biomass (3028 kg per hectare). The highest carbon content of fine woody debris was found in the shelterwood stand (531 kg per hectare), while the highest carbon content of coarse woody debris was observed in the protected stand (1989 kg per hectare). The forest accessibility index showed the strongest negative correlation with coarse woody debris volume. Additionally, fine woody debris volume had a significant positive correlation with slope gradient and distance from the road.
Conclusion: This study demonstrated that lower-intensity management practices with longer harvest cycles (such as the shelterwood method with a 40-year interval) can largely maintain the carbon storage capacity and natural decay dynamics of woody debris, allowing recovery to conditions close to those of the conservation stand. In contrast, repeated human disturbances (especially the combined harvesting of standing and windthrown trees) rapidly deplete these vital stocks and shift their dynamics toward fresh, fast-decomposing material. Forest accessibility was identified as the strongest determinant of woody debris quantity. It is recommended that forest management plans in the Hyrcanian region prioritize the preservation of areas with difficult access, avoid the complete removal of logging residues, and favor close-to-nature silvicultural practices to maintain carbon sequestration functionss and biodiversity.

Keywords

Main Subjects

References

[1] Fukasawa, Y. (2012). Effects of wood decomposer fungi on tree seedling establishment on coarse woody debris. Forest Ecology and Management, 266, 232-238.
[2] Kunttu, P., Junninen, K. & Kouki, J. (2015). Dead wood as an indicator of forest naturalness: A comparison of methods. Forest Ecology and Management, 353, 30-40.
[3] Jonsson, B.G., Ekström, M., Esseen, P.A., Grafstrom, A., Stahl, G. & Westerlund, B. (2016). Dead wood availability in managed Swedish forests—Policy outcomes and implications for biodiversity. Forest Ecology and Management, 376, 174-182.
[4] Jaroszewicz, B., Cholewinska, O., Checko, E. & Wrzosek, M. (2021). Predictors of diversity of deadwood-dwelling macrofungi in a European natural forest. Forest Ecology and Management, 490, 119123.
[5] Tavankar, F., Latterini, F., Nikooy, M., Venanzi, R., Naghdi, R. & Picchio, R. (2021). Influence of forest management and sylvicultural treatments on abundance of snags and tree cavities in mountain mixed beech forests. Environments, 8(6), 55.
[6] Lutz, J.A., Struckman, S., Furniss, T.J., Birch, J.D., Yocom, L.L. & McAvoy, D.J. Large-diameter trees, snags, and deadwood in southern Utah, USA. Ecological Processing, 10(1), 1-12.
[7] Iranian Organization of Natural Resources and Watersheds, Forest Section, Guidelines for preparing sustainable management plan for Hyrcanian forests, Section of measuring and statistics, Version 14020715, 25 p.
[8] Harmon, M.E., K. Bible, M.G. Ryan, D.C. Shaw, H. Chen, J. Klopatek & and X. Li, (2004). Production, respiration, and overall carbon balance in an old-growth Pseudotsuga Tsuga forest ecosystem, Ecosystems, 7(5), 498-512.
[9] Öder, V., Petritan, A.M., Schellenberg, J., Bergmeier, E. & Walentowski, H. (2021). Patterns and drivers of deadwood quantity and variation in mid-latitude deciduous forests. Forest Ecology and Management, 487, 118977.
[10] Behjou, F.K., Aghayari, F. & Ghanbari, S. (2023). Management and the amount and density of woody debris at the West forests of Guilan Province. Human and Environment, 21(1), 51-64.
[11] Izadi, S. & Sohrabi, H. (2015). Estimating the volume of coarse woody debris of forest floor using sampling with probability proportional methods. Iranian Journal of Forest and Poplar Research, 23(2), 222-233.
[12] Sefidi, K. (2020). The Influence of Geomorphological Characteristics of Forest Sites on the Decay Dynamics of Dead Trees in Asalem Forests, Western Hyrcanian Region. Ecology of Iranian Forests, 7(14), 70-79.
[13] Corace, R.G., Seefelt, N.E., Goebel, P.C. & Shaw, H.L. (2010). Snag longevity and decay class development in a recent jack pine clear-cut in Michigan. Northern Journal of Applied. Forestry, 27(4), 125-131.
[14] Lo Monaco, A., Luziatelli, G., Latterini, F., Tavankar, F. & Picchio, R. (2020). Structure and Dynamics of Deadwood in Pine and Oak Stands and their Role in CO2 Sequestration in Lowland Forests of Central Italy. Forests, 11(3), 253.
[15] Jones, D.A. & O’Hara, K.L. (2016). The influence of preparation method on measured carbon fractions in tree tissues. Tree Physiology, 36(9), 1177-1189.
[16] Wisdom, M.J. & Bate, L.J. (2008). Snag density varies with intensity of timber harvest and human access. Forest Ecology and Management, 255(7), 2085-2093
[17] Bantle, A., Borken, W. & Matzner, E. (2014). Dissolved nitrogen release from coarse woody debris of different treespecies in the early phase of decomposition. Forest Ecology and Management, 334, 277-283.
[18] Schelhaas, M.J., Nabuurs, G.J. & Schuck, A. (2003). Natural disturbances in the European forests in the 19th and 20th centuries. Global Change Biology, 9(11), 1620-1633.
[19] Banas, J., Bujoczek, L., Zieba, S. & Drozd, M. (2014). The effects of different types of management, functions, and characteristics of stands in Polish forests on the amount of coarse woody debris. European Journal of Forestry Research, 133(6), 1095-1107.
[20] Lombardi, F., Lasserre, B., Tognetti, R. & Marchetti, M. (2008). Deadwood in Relation to Stand Management and Forest Type in Central Apennines (Molise, Italy). Ecosystems, 11(6), 882-894.
[21] Behjou, F.K., Lo Monaco, A., Tavankar, F., Venanzi, R., Nikooy, M., Mederski, P.S. & Picchio, R. (2018). Coarse Woody Debris Variability Due to Human Accessibility to Forest. Forests, 9(9), 509.
[22] Chen, Y.; Sayer, E.J.; Li, Z.; Mo, Q.; Li, Y.; Ding, Y.; Wang, J. Nutrient limitation of woody debris decomposition in a tropical forest: contrasting effects of N and Paddition. Functional Ecology, 30, 295-304.
[23] Shabani, S., Vahedi, A.A. 2024. Modeling the role of FWD on plant species richness using BRT. Forest Research and Development, 10(1), 131-147.
[24] Barbosa, R.I., Castilho, C.V., Perdiz, R.O., Damasco, G., Rodrigues, R. & Fearnside. P.M. (2017). Decomposition rates of coarse woody debris in undisturbed Amazonian seasonally flooded and unflooded forests in the Rio Negro-Rio Branco Basin in Roraima, Brazil. Forest Ecology and Management, 397, 1-9.
[25] Law, S., Eggleton, P., Griffiths, H., Ashton, L. & Parr, C. (2019). Suspended dead wood decomposes slowly in the tropics, with microbial decay greater than termite decay. Ecosystems, 22(6), 1176-1188.
[26] Khan, K., Tuyen, T.T., Chen, L., Duan, W., Hussain, A., Jamil, M.A., Li, C., Guo, Q., Qu, M., Wang, Y. et al. (2021). Nutrient dynamics assessment of coarse wood debris subjected to successional decay levels of three forests types in northeast, China. Forests, 12(4), 401.
[27] Kiadaliri, M.; Motlagh, M.G.; Sohrabi, H.; Latterini, F.; Lo Monaco, A.; Venanzi, R. & Picchio, R. (2023). The Effects of Forest Accessibility on the Quantitative and Qualitative Characteristics of Deadwood: A Comparison between Recreational and Natural Forests. Sustainability, 15(13), 10592.
[28] Fan Z., Larsen D.R., Shilley S.R. & Thompson F.R. (2003). Estimating cavity tree abundance by stand age and basal area, Missouri, USA. Forest Ecology and Management, 179(1-3), 231-242.
[29] Fan Z., Shifley S.R., Thompson, F.R. & Larsen, D.R. (2004). Simulated cavity tree dynamics under alternative timber harvest regimes. Forest Ecology and Management, 193(3), 399-412.
[30] Christensen, M., Hahn, K., Mountford, E.P., Ódor Standovár, T., Rozenbergar, D., Diaci, J., Wijdeven, S., Meyer, P., Winter, S., Vrska, T. (2005). Dead Wood in European Beech (Fagus sylvatica) Forest Reserves. Forest Ecology and Management, 210(1-3), 267-282.
[31] Böhl J. & Brändli U.B. (2007). Deadwood volume assessment in the third swiss national forest inventory: methods and first results. European Journal of Forest Research, 126(3), 449-457.
[32] Nagaike T. (2009). Snag abundance and species composition in a managed forest landscape in central Japan composed of Larix kaempferi plantation and secondary broadleaf forests. Silva Fennica, 43(5), 755-766.
[33] Sefidi, K. & Marvie Mohadjer, M.R. (2010). Characteristics of coarse woody debris in successional stages of natural beech (Fagus orientalis) forests of Northern Iran. Journal of Forest Science, 56(1), 7-17.
[34] Tavankar, F., Kivi, A.R., Taheri-Abkenari, K., Lo Monaco, A., Venanzi, R. & Picchio, R. (2022). Evaluation of Deadwood Characteristics and Carbon Storage under Different Silvicultural Treatments in a Mixed Broadleaves Mountain Forest. Forests, 13(2), 259.
[35] Bate, L.J., Wisdom, M.J. & Wales, B.C. (2007). Snag densities in relation to human access and associated management factors in forests of northeastern Oregon. Landscape and Urban Planning, 80(3), 278-291.
[36] Wisdom, M.J. & Bate, L.J. (2008). Snag density varies with intensity of timber harvest and human access. Forest Ecology and Management, 255(7), 2085-2093.
Forest and Wood Products
Volume 79, Issue 1
June 2026
Pages 51-65

Files

Share

How to cite

Statistics