Effect of canopy gap size and ecological factors on species diversity and beech seedlings in managed beech stands in Hyrcanian forests

Abstract

We studied the species diversity of the herb layer and ecological factors in harvest-created gaps in beech stands under a single-tree selection system in Northern Iran. To determine diversity, the number of beech seedlings, and other ecological factors, 16 gaps were selected and subplots of 5 m² were positioned at the centre and at the cardinal points of each gap. Species richness and Simpson diversity index increased with increasing gap area as did numbers of seedlings. With increasing humus layer thickness, species richness declined but the Hill evenness index increased. Species richness increased with increasing light availability. There was no relationship between crown radii of beech trees and diversity indices. Correlations between environmental factors and numbers of individuals of some species in the herb layer were not significant except in a few cases. The results help explain the effects of man-made gaps on the dynamics of managed beech stands and this benefits evaluation of silvicultural operating plans.

Keywords

beech / gap / herbaceous species / diversity / Hyrcanian forests

References

[1] Abd Latif Z., Blackburn G.A.. The effects of gap size on some microclimate variables during late summer and autumn in a temperate broadleaved deciduous forest. International Journal of Biometeorol, 2010, 54: 119-129.

[2] Abrari Vajari K., Azizi P.. Recognition of plant association in Fagetum of Khoshkab zone (Siyakal-Deylaman). Journal of Agricultural Sciences and Natural Resources, 2002, 9(2): 3-13.

[3] Albanesi E., Guliotta D., Mercurio I., Mercurio R.. Effects of gap size and within-gap position on seedlings establishment in silver fir stands. Forest, 2005, 2(4): 258-366.

[4] Andersson M.. Effects of pH and Aluminium on growth of Galium odratum (L.) SCOP. Insolution culture. Environmental and Experimental Botany, 1992, 32: 497-501.

[5] Banj Shafiei A.B., Akbarinia M., Jalali G., Hosseini M.. Forest fire effects in beech dominated mountain forest of Iran. Forest Ecology and Management, 2010, 259: 2191-2196.

[6] Barbier S., Gosselin F., Balandier P.. Influence of tree species on understory vegetation diversity and mechanisms involved — A critical review for temperate and boreal forests. Forest Ecology and Management, 2008, 254: 1-15.

[7] Battles J.J., Shlisky A.J., Barrett R.H., Heald R.C., Allen-Diaz B.H.. The effects of forest management on plant species diversity in a Sierran conifer forest. Forest Ecology and Management, 2001, 146: 211-222.

[8] Blair B.C., Letourneau D.K., Bothwell S.G., Hayes G.F.. Disturbance, resources, and exotic plant invasion: gap size effects in a redwood forest. Madroño, 2010, 57: 11-19.

[9] Bullock J.M.. Fenner M.. Gaps and seedling colonization. Seeds: the ecology of regeneration in plant communities, 2000 2nd ed Wallingford UK: CABI, 375 395

[10] Chiarucci A., Bacaro G., Rocchini D.. Quantifying plant species diversity in a Natura 2000 network: old idea and new proposals. Biological Conservation, 2008, 141: 2608-2618.

[11] Degen T., Devillez F., Jacquemart A.L.. Gaps promote plant diversity in beech forests (Luzulo-Fagetum) North Vosges, France. Annals Forest Science, 2005, 62: 429-440.

[12] Dobrowolska D., Veblen T.T.. Treefall-gap structure and regeneration in mixed Abies alba stands in central Poland. Forest Ecology and Management, 2008, 255: 3469-3476.

[13] Ellum D.S., Ashton M.S., Siccama T.G.. Spatial pattern in herb diversity and abundance of second growth mixed deciduous-evergreen forest of southern New England, USA. Forest Ecology and Management, 2010, 259: 1416-1426.

[14] Elliott K.J., Knoepp J.D.. The effects of three regeneration harvest methods on plant diversity and soil characteristics in the southern Appalachians. Forest Ecology and Management, 2005, 211: 296-317.

[15] Eshaghi Rad J., Zahedi Amiri G., Marvi Mohajer M.R., Mataji A.. Relationship between vegetation and physical and chemical properties of soil in Fagetum communities (Case study: Kheiroudkenar forest). Iranian Journal of Forest and Poplar Research, 2009, 17(2): 174-187.

[16] Falk K.J., Burke D.M., Elliott K.A., Holmes S.B.. Effects of single-tree and group selection harvesting on the diversity and abundance of spring forest herbs in deciduous forests in southwestern Ontario. Forest Ecology and Management, 2008, 255: 2486-2494.

[17] Jefferson R.G.. Biological flora of the British Isles: Mercurialis perennis L. Journal of Ecology, 2008, 96: 386-412.

[18] Jones T.A., Domke G.M., Thomas S.C.. Canopy tree growth response following selection harvest in seven species varying in shade. Can J For Res, 2008, 39: 430-440.

[19] Gálhidy L., Mihók B., Hagyó A., Rajkai K., Standovár T.. Effects of gap size and associated changes in light and soil moisture on the understorey vegetation of a Hungarian beech forest. Plant Ecology, 2006, 183: 133-145.

[20] Gilliam F.S., Turrill N.L., Beth Adams M.. Herbaceous-Layer and Overstory Species in Clear-cut and Mature Central Appalachian Hardwood Forests. Ecological Applications, 1995, 5: 947-955.

[21] Gracia M., Montané F., Piqué J., Retana J.. Overstory structure and topographic gradients determining diversity and abundance of understory shrub species in temperate forests in central Pyrenees (NE Spain). Forest Ecology and Management, 2007, 242: 391-397.

[22] Härdtle W., Von Oheimb G., Westphal C.. The effects of light and soil conditions on the species richness of the ground vegetation of deciduous forests in northern Germany (Schleswig-Holstein). Forest Ecology and Management, 2003, 182: 327-338.

[23] Kern C.C., Palik B.J., Strong T.F.. Ground-layer plant community responses to even-age and uneven-age silvicultural treatments in Wisconsin northern hardwood forests. Forest Ecology and Management, 2006, 230: 162-170.

[24] Kimberly L.A., Leopard D.J.. The role of canopy gaps in maintaining vascular plants diversity at forested wetland in New York State. Journal of the Torrey Botanical Society, 2002, 129: 238-250.

[25] Kukkonen M., Rita H., Hohenwald S., Nygren A.. Treefall gaps of certified, conventionally managed and natural forest as regeneration sites for Neotropical timber forest in northern Honduras. Forest Ecology and Management, 2008, 255: 2163-2176.

[26] Masarovičová E., Eliáŝ P.. Seasonal changed in the photosynthetic response of Mercurialis perennis plants from different light regime conditions. Biologica Plantarum, 1985, 27(1): 41-50.

[27] Menges E.S., Craddock A., Salo J., Zinthefer R., Weekley C.W.. Gap ecology in Florida scrub: Species occurrence, diversity and gap properties. Journal of Vegetation Science, 2008, 19: 503-514.

[28] Mihók B., Gálhidy L., Kenderes K., Standovar T.. Gap Regeneration Patterns in a Semi-natural Beech Forest Stand in Hungary. Acta Silv Lign Hung, 2007, 3: 31-45.

[29] Mölder A., Bernhardt-Romermann M., Schmidt W.. Herb-layer diversity in deciduous forests: Raised by tree richness or beaten by beech. Forest Ecology and Management, 2008, 256: 272-281.

[30] Naaf T., Wulf M.. Effects of gap size, light and herbivory on the herb layer vegetation in European beech forest gaps. Forest Ecology and Management, 2007, 244: 141-149.

[31] Nagaike T., Kamitania T., Nakashizuka T.. effect of shelterwood logging on the diversity of plant species in a beech (Fagus crenata) forest in Japan. Forest Ecology and Management, 1999, 118: 161-171.

[32] North M., Oakley B., Fiegener R., Gray A., Barbour M.. Influence of light and soil moisture on Sierran mixed-conifer understory communities. Plant Ecology, 2005, 177: 13-24.

[33] Pykälä J.. Immediate increase in plant species richness after clear-cutting of boreal herb-rich forests. Applied Vegetation Science, 2004, 7: 29-34.

[34] Nowińska R.. Reactions of the herb and moss layer, tree saplings and the shrub layer to tree deaths in forests of the Wielkopolska National Park (Western Poland). Biologica, 2010, 65(5): 265-272.

[35] Peltzer D.A., Bast M.L., Wilson S.D., Gerry A.K.. Plant diversity and tree responses following contrasting disturbances in boreal forest. Forest Ecology and Management, 2000, 127: 191-203.

[36] Pitkänen S.. Classification of vegetational diversity in managed boreal forests in eastern Finland. Plant Ecology, 2000, 146: 11-28.

[37] Poorbabaei H., Poor-rostam A.. The effect of shelterwood silvicultural method on the plant species diversity in a beech (Fagus orientalis Lipsky) forest in the north of Iran. Journal of Forest Science, 2009, 55(8): 387-394.

[38] Pourmajidian M.R., Malakshah N.E., Fallah A., Parsakhoo A.. Evaluating the shelterwood harvesting system after 25 years in a beech (Fagus orientalis Lipsky) forest in Iran. Journal of Forest Science, 2009, 55: 270-278.

[39] Pre’vosto B., Bousquet-Me’lou A., Ripert C., Fernandez C.. Effects of different site preparation treatments on species diversity, composition, and plant traits in Pinus halepensis woodlands. Plant Ecology, 2010, 212: 627-638.

[40] Pritchard J.M., Comeau P.G.. Effectes of opening size and stand characteristics on light transmittance and temperature under young trembling aspen stands. Forest Ecology and Management, 2004, 200: 119-128.

[41] Qiu R.H., Chen H., Zhuo L.X.. Effects of selection cutting on the forest structure and species diversity of evergreen broad-leaved forest in northern Fujian, southern China. Forestry Study in China, 2006, 8: 16-20.

[42] Romell E., Hallsby G., Karlsson A.. Forest floor light condition in a secondary tropical rainforest after artificial gap creation in northern Borneo. Agriculture and Forest Meterology, 2009, 149: 929-937.

[43] Runkle J.R.. Gap regeneration in some old-growth forests of the Eastern United States. Ecology, 1981, 42(4): 1041-1051.

[44] Sapkota I.P., Tigabu M., Odén P.C.. Species diversity and regeneration of old-growth seasonally dry Shorea robusta forests following gap formation. Journal of Forestry Research, 2009, 20: 7-14.

[45] Shumann M., White A.S., Witham J.W.. The effect of harvest-created gaps on plant species diversity, composition, and abundance in a maine Oak-pine forest. Forest Ecology and Management, 2003, 176: 543-561.

[46] Singh J.S.. The biodiversity crisis: A multifaceted reviews the biodiversity crisis: a multifaceted review. Current Science, 2002, 82: 63-73.

[47] Sydes C., Grime J.P.. Effects of tree leaf litter on herbaceous vegetation in deciduous woodland. I. Field investigations. Journal of Ecology, 1981, 69: 237-248.

[48] Sydes C., Grime J.P.. Effects of tree leaf litter on herbaceous vegetation in deciduous woodland. II. An experimental investigation. Journal of Ecology, 1981, 69: 249-262.

[49] Torras O., Saura S.. Effects of silvicultural treatments on forest biodiversity indicators in the Mediterranean. Forest Ecology and Management, 2008, 255: 3322-3330.

[50] Van Oijen D., Feijen M., Hommel P., den Oden J., Waal R.. Effects of tree species composition on within-forest distribution of understorey species. Applied Vegetation Science, 2005, 8: 155-166.

[51] Zhao X.H., Zhang C.Y., Zheng J.M.. Correlations between canopy gaps and species diversity in broad-leaved and Korean pine mixed forests. Frontiers of Forestry in China, 2006, 4: 372-378.

[52] Zhu J.J., Mao Z.H., Hu L.L., Zhang J.X.. Plant diversity of secondary forests in response to anthropogenic disturbance levels in montane regions of northeastern China. Journal of Forest Research, 2007, 12: 403-416.

[53] Zhu W.Z., Cheng S., Cai X.H., He F., Wang J.X.. Changes in plant species diversity along a chronosequence of vegetation restoration in the humid evergreen broad-leaved forest in the Rainy Zone of West China. Ecological Research, 2009, 24: 315-325.