Density effect and self-thinning in Eucalyptus urophylla stands

Abstract

Density effects on the growth and self-thinning of Eucalyptus urophylla stands were examined for 7 years. The reciprocal equation of the competition-density (C–D) effect was used to describe the C–D effect in even-aged pure stands of E. urophylla during course of self-thinning and showed a good fit to the data. The time trajectories of mean stem volume-density nearly paralleled the y-axis during early growth stages of stands, and then began to curve left. Finally, the mean stem volume-density trajectories of the low-, middle- and high-density stands tended to follow the self-thinning lines with slopes of − 2.01, − 1.90 and − 1.99, respectively. With increasing physical time t, the biological time τ increased rapidly during early growth stages and became slow gradually during later growth stages. Realized density-initial density curves tended to become more or less flat with increasing initial density, indicating the existence of an asymptotic value for density at a given time. The coefficient ε, the reciprocal of which represents the asymptotic density at a given time, increased with increasing biological time τ, indicating that the asymptotic density decreased with increasing stand age. Final yield Y(t) increased gradually with increasing stand age.

Keywords

C–D effect / General logistic curve / Eucalyptus urophylla / Reciprocal equation / Self-thinning

References

[1] Baldwin VC Jr, Peterson KD, Clark A III, Ferguson RB, Strub MR, Bower DR. The effects of spacing and thinning on stand and tree characteristics of 38-year-old loblolly pine. For Ecol Manage, 2000, 137: 91-102.

[2] Begon M, Harper JL, Townsend CR. Ecology: individuals, populations and communities, 1996, Oxford: Blackwell Science

[3] Bleasdale JKA. The relationship between the weight of a plant part and total weight as affected by plant density. J Hortic Sci, 1967, 42: 51-58.

[4] Bleasdale JKA, Nelder JA. Plant population and crop yield. Nature, 1960, 188: 342.

[5] Burkes EC, Will RE, Barron-Gafford GA, Teskey RO, Shiver B. Biomass partitioning and growth efficiency of intensively managed Pinus taeda and Pinus elliottii stands of different planting densities. For Sci, 2003, 49(2): 224-234.

[6] Cole E, Newton M. Fifth-year response of Douglas-fir to crowding and non-coniferous competition. Can J For Res, 1987, 17: 181-186.

[7] Farazdaghi H, Harris PM. Plant competition and crop yield. Nature, 1968, 217: 289-290.

[8] Giordano PA, Hibbs DE. Morphological response to competition in red alder: the role of water. Funct Ecol, 1993, 7: 462-468.

[9] Hagihara A. Logistic theory of the density effect in self-thinning populations. Bull Nagoya Univ For, 1996, 15: 31-50. (in Japanese with English summary)

[10] Hagihara A. Theoretical studies on the time-trajectory of mean plant weight and density in self-thinning populations. Bull Nagoya Univ For, 1996, 15: 51-67. (in Japanese with English summary)

[11] Hagihara A. A practical model for the time-trajectory of mean phytomass and density in the development of even-aged pure stands. J For Plann, 1998, 4: 65-69.

[12] Hagihara A. Theoretical considerations on the C–D effect in self-thinning plant populations. Res Popul Ecol, 1999, 41: 151-159.

[13] Hozumi K. Ecological and mathematical considerations on self-thinning in even-aged pure stands. I. Mean plant weight-density trajectory during the course of self-thinning. Bot Mag Tokyo, 1977, 90: 165-179.

[14] Jack SB, Long JN. Linkages between silviculture and ecology: an analysis of density management diagrams. For Ecol Manage, 1996, 86: 205-220.

[15] Knowe SA, Hibbs DE. Stand structure of young red alder as affected by plant density. For Ecol Manage, 1996, 82: 69-85.

[16] Lanner RM. On the insensitivity of height growth to spacing. For Ecol Manage, 1985, 13: 143-148.

[17] Minowa M. A theoretical approach to forest growth model. I. The log-Mitscherlich theory. J Jpn For Soc, 1982, 64: 461-467. (in Japanese with English summary)

[18] Mohler CL, Marks PL, Sprugel DG. Stand structure and allometry of trees during self-thinning of pure stands. J Ecol, 1978, 66: 599-614.

[19] Naito K. Studies on forest growth modeling. Bull Utsunomiya Univ For, 1992, 28: 1-95. (in Japanese with English summary)

[20] Nelder JA. New kinds of systematic designs for spacing experiments. Biometrics, 1962, 18: 283-307.

[21] Norberg RA. Theory of growth geometry of plants and self-thinning of plant populations: geometric similarity, elastic similarity, and different growth models of plant parts. Am Nat, 1988, 131: 220-256.

[22] Ogawa K. Time trajectories of mass and density in a Chamaecyparis obtusa seedling population. For Ecol Manage, 2001, 142: 291-296.

[23] Ogawa K. Time-trajectory of mean phytomass and density during a course of self-thinning in a sugi (Cryptomeria japonica D. Don) plantation. For Ecol Manage, 2005, 214: 104-110.

[24] Ogawa K, Hagihara A. Self-thinning and size variation in a sugi (Cryptomeria japonica D. Don) plantation. For Ecol Manage, 2003, 174: 413-421.

[25] Pienaar LV, Shiver BD. Early results from an old-field loblolly pine spacing study in the Georgia Piedmont with competition control. South J Appl For, 1993, 17: 193-196.

[26] Prasad JVNS, Korwar GR, Rao KV, Srinivas K, Rao CAR, Srinivasarao CH, Venkateswarlu B. Effect of modification of tree density and geometry on intercrop yields and economic returns in Leucaena-based agro-forestry systems for wood production in Andhra Pradesh, Southern India. Exp Agric, 2010, 46(2): 155-172.

[27] Seidel KW (1984) A western larch-Engelmann spruce spacing study in eastern Oregon: results after 10 years. In: USDA Forest Service Note PNW-409

[28] Shinozaki K (1961) Logistic theory of plant growth. Doctoral Thesis, Kyoto University, Kyoto (in Japanese)

[29] Shinozaki K, Kira T. Intraspecific competition among higher plants. VII. Logistic theory of the C–D effect. J Inst Polytech Osaka City Univ Ser D, 1956, 7: 35-72.

[30] Silvertown JW, Doust JL. Introduction to plant population biology, 1993, Oxford: Blackwell Science.

[31] Solomon DS, Zhang LJ. Maximum size-density relationships for mixed softwoods in the northeastern USA. For Ecol Manage, 2002, 155: 163-170.

[32] Tadaki Y. Structure and productivity of young Castanopsis cuspidata forests growing in different stand densities. Bull Nagoya Univ For, 1995, 14: 1-24. (in Japanese with English summary)

[33] Vandermeer J. Plant competition and the yield-density relationship. J Theor Biol, 1984, 109: 393-399.

[34] Watkinson AR. Density-dependence in single-species populations of plants. J Theor Biol, 1980, 83: 345-357.

[35] Watkinson AR. Yield-density relationships: the influence of resource availability on growth and self-thinning in populations of Vulpia fasciculate. Ann Bot, 1984, 53: 469-482.

[36] Weller DE. Self-thinning exponent correlated with allometric measures of plant geometry. Ecology, 1987, 68: 813-821.

[37] Weller DE. A reevaluation of the −3/2 power rule of plant self-thinning. Ecol Monogr, 1987, 57: 23-43.

[38] White J. The allometric interpretation of the self-thinning rule. J Theor Biol, 1981, 89: 475-500.

[39] Xue L, Hagihara A. Growth analysis of the self-thinning stands of Pinus densiflora Sieb. et Zucc. Ecol Res, 1998, 13: 183-191.

[40] Xue L, Hagihara A. Density effect, self-thinning and size distribution in Pinus densiflora Sieb. et Zucc. stands. Ecol Res, 1999, 14: 49-58.

[41] Xue L, Hagihara A. Growth analysis on the competition-density effect in Chinese fir (Cunninghamia lanceolata) and Masson pine (Pinus massoniana) stands. For Ecol Manage, 2001, 150: 331-337.

[42] Xue L, Hagihara A. Growth analysis on the C–D effect in self-thinning Masson pine (Pinus massoniana) stands. For Ecol Manage, 2002, 165: 249-256.

[43] Xue L, Hagihara A. Density effects on tree organs in self-thinning Pinus densiflora Sieb. et Zucc. stands. Ecol Res, 2008, 23: 689-695.

[44] Xue L, Feng HF, Chen FX. Time-trajectory of mean component weight and density in self-thinning Pinus densiflora stands. Eur J For Res, 2010, 129: 1027-1035.

[45] Yang WD, Zhong LS. Researches on the experiment of planting densities for new introduction Eucalyptus urophylla. Eucalypt Sci Tech, 1997, 14(2): 37-41. in Chinese

[46] Yoda K, Kira T, Ogawa H, Hozumi K. Self-thinning in overcrowded pure stands under cultivated and natural conditions (Intraspecific competition among higher plants. XI.). J Biol Osaka City Univ, 1963, 14: 107-129.

[47] Zeide B. Tolerance and self-tolerance of trees. For Ecol Manage, 1985, 13: 149-166.