Comparison of tree growth and undergrowth development in aerially seeded and planted Pinus tabulaeformis forests

Abstract

Direct seeding is a less expensive practice than planting and has the potential to become a viable alternative to transplanting for afforestation and regeneration purposes. As an effective and a less costly regeneration method, aerial seeding has been applied with several tree species. As early as 1956, Chinese people engaged in aerial seeding and stands with a total of 2.97×10⁷ hm² have been developed up to 2004. Our study tested whether the growth of planted Chinese pine (Pinus tabulaeformis Carr.) seedlings and its undergrowth development in northwest aspects differ from that of aerially sown seedlings on the northern and northwestern aspects of slopes. In 2007, we collected data such as height, diameter at breast height (DBH), clear bole height and canopy widths of trees, abundance, coverage, and frequency of shrubs and herbs from 21-year-old planted Chinese pine stands on a northwestern aspect (PNW), aerially sown stands in a northwest aspect (ANW) and aerially sown stands in a northern aspect (AN). Results showed that the relation of crown area and mean DBH was best fitted by a double inverse model for the ANW and AN forests and by a quadratic model for the PNW forest. There was no difference in the growth between ANW and AN forests, while growth was significantly higher in the PNW forest than in the ANW and AN forests. That was consistent with the Sorenson diversity indices in the shrub and herb layers, indicating that there was a large number of the same species in both aerially seeded stands, although their locations were different. Both the number of species in the undergrowth and the Shannon-Wiener index in the shrub layer were higher in the PNW stands than in the ANW and AN stands. Dominant families for all three stands were Rosaceae and Compositae in the shrub and herb layer, respectively. The dominant species for all three stands was Spiraea pubescens in the shrub layer, while the dominant species was different from each other in the three stands. The discrepancy in diversity and composition of species in the herb layer show that herbs are sensitive to shrubs in the three forests. High mortality and skewed diameter distributions reflect severe competition and too high a density in the aerially seeded forests. Thus, aerial seeding is a viable and effective regeneration technique, but management practices, such as thinning, should be applied to these forests.

Key words： Pinus tabulaeformis; growth; undergrowth; aerial seeding; planting; slope; aspect

Acknowledgments

This study was jointly supported by the National Natural Science Foundation of China (Grant No. 30471380) and Education Committee of Beijing (Contract No. JD100220648).

References

1 Ammer C, Mosandl R (2007). Which grow better under the canopy of Norway spruce-planted of sown seedlings of European beech? Forestry, 80(4): 385-394

2 Balandier P, Collet C, Miller J H, Reynolds P E, Zedaker S M (2006). Designing forest vegetation management strategies based on the mechanisms and dynamics of drop tree competition by neighboring vegetation. Forestry, 79: 3-27

3 Coll L, Balandier P, Picon-Cochard C (2004). Morphological and physiological responses of beech (Fagus sylvatica) seedlings to grass-induced belowground competition. Tree Physiol, 24: 45-54

4 Collet C, Moguedec G (2007). Individual seedling mortality as a function of size, growth and competition in naturally regenerated beech seedlings. Forestry, 80(4): 359-370

5 Conard S G, Regelbrugge J C, Wills R D (1991). Preliminary effects of ryegrass seeding on postfire establishment of natural vegetation in two California ecosystems. In: the 11th Conference on Fire and Forest Meteorology, Missoula, Montana

6 Curtis J T, McIntosh R P (1951). An upland forest continuum in the prairie-forest border region of Wisconsin. Ecology, 32: 467-496

7 Faulkner M E, Trotman I G, Garnett B T (1990). Aerial seedling of pines for protection afforestation: Kaweka Forest, Hawke’s Bay. New Zealand J For, 2: 81-90

8 Guo T L, Li S L, Bai J, Wang X L, Zhang L. 2004. Study on thinning technique of air-seeded forest of Pinus tabulaeformis. Protect For Sci Technol, 5: 63-64 (in Chinese)

9 Jiang Y X, Guo Q S, Ma J (1998). Community Characteristics and Classification in China. Beijing: Science Press & China Forestry Publishing House: 3-20 (in Chinese)

10 Keeley Jon E, Allen C D, Julio Betancourt, Chong Geneva W, Fotheringham C J, Safford H D (2006). A 21st century perspective on postfire seeding. J For, 1: 1-2

11 Li G L, Liu Y, Gan J, Guo B, Xu Y (2008). Seasonal response of soil enzyme activity to thinning intensity of aerial seeding Pinus tabulaeformis stands. J Beijing For Univ, 30(2): 82-88 (in Chinese)

12 Li G L, Liu Y, Guo B, Xu yang, Zhang K D, Zhao S R (2007a). Effect of reserve density on undergrowth development of aerial seeding Pinus tabulaeformis stands. J Northwestern Coll For, 22(1): 72-77 (in Chinese)

13 Li G L, Liu Y, X Y, Guo B, Zhang K D, Zhao S R (2007c). Effect of thinning intensities on the development of the undergrowth in Pinus tabulaeformis plantation. J Beijing For Univ, 29(2): 70-75 (in Chinese)

14 Li G L, Zhao Y J, Chen J H (2007b). Present situation and sustainable developmental countermeasures of the plan-seeding forest resources in China. Bull Soil Water Conserv, 27(3): 161-166 (in Chinese)

15 Li G Y (1992). Management on Secondary Forest in North China. Beijing: China Forestry Publishing House, 478-487 (in Chinese)

16 Li Z H, Qi F H, Bai F M, Chen X P, He Y J (2004). Studies of the soil fertility of aerially seeded Pinus massoniana stands. J Centr South For Univ, 24(5): 32-35 (in Chinese)

17 Liu J J, Yang C, Wu C R (1991). The spatial pattern of air-seeded forest of Pinus tabulaeformis. J Northwestern Coll For, 6(2): 51-54 (in Chinese)

18 Liu X D, Wu Q X, Hou Q C, Shi L M (1983). Ecological distribution of aerial Chinese pine seedlings. Bull Soil Water Conserv, 3(6): 77-82 (in Chinese)

19 Liu Z C, Wang T R, Zhang H W, Liu X X (2003). Stand density-control map making for Chinese pine forest sowed by airplane in Henan Province. For Sour Manage, 4: 24-27 (in Chinese)

20 Löf M, Thomsen A, Madsen P (2003). Sowing and transplanting of broadleaves (Fagus sylvatica L.), Quercus robur L., Prunus avium L. and Crataegus monogyna Jacq. for afforestation of farmland. For Ecol Manage, 188: 113-123

21 Lu W D. 2005. SPSS for Windows Statistical Analysis. Beijing: Electronics Industry Publishing House

22 Meng X Y. 2006. Forest Mensuration. 2nd. Beijing: China Forestry Publishing House (in Chinese)

23 Morris D M, Bowling C, Hills S C (1994). Growth and form responses to pre-commercial thinning regimes in aerially seeded jack pine stands: 5th year response. For Chron, 70(6): 780-787

24 Nilsson U, Gemmel P, Löf M, Welander T (1996). Germination and early growth of sown Quercus robur L. in relation to soil preparation, sowing depth and prevention against predation. New For, 12: 69-86

25 Ott J E, Mc-Arthur E D, Roundy B A (2003). Vegetation of chained and non-chained seedlings after wildfire in Utah. J Range Manage, 56(1): 81-91

26 Shainsky L J, Radosevich S (1999). Mechanisms of competition between Douglas-fir and red alder seedling. Ecology, 73(1): 30-45

27 Shen G J (2001). Silviculture. Beijing: China Forestry Publishing House (in Chinese)

28 Shen W S (1999). Successional stage and rate of the aerial seeding vegetation in the Maowusu Sandyland. Sci Silv Sin, 35(3): 103-108 (in Chinese)

29 Yang C (1996). On growth rhythms of aerial seeding forest of Pinus tabulaeformis Carr. J Northwest For Coll, 11(4): 24-27 (in Chinese)

30 Zhang G C, Liu X, Zhou Z F, Zhang S Y, Liu G, Chen J (2007). Growth process and diameter structure of Pinus tabulaeformis forest for soil and water conservation in Loess Plateau hilly regions. Chin J Appl Ecol, 18(4): 728-734 (in Chinese)

31 Zhang J T (2004). Quantitative Ecology. Beijing: Science Press, 24 (in Chinese)

32 Zhou D M, Chen X P, Zhang J X, Tian B B, Li Z H (2002). Study of soil microorganisms in air-sowing Pinus massoniana stands. J Centr South For Univ, 22(3): 59-62 (in Chinese)