Responses of aboveground net primary production and population structure of Caragana microphylla to prescribed burning in a typical steppe of Inner Mongolia

Abstract

Abstract: The density and cover of the native shrub species Caragana microphylla, has greatly increased in recent decades in the Xilin River basin of Inner Mongolia, in areas previously dominated by Leymus chinensis and Stipa grandis. We conducted a field experiment of one- and two-years burning in a typical successional steppe dominated by C. microphylla. Our main objective was to determine whether and how the prescribed burning can be used as a management tool for controlling shrub encroachment of the Inner Mongolia grasslands. The effects of prescribed burning on morphological traits, aboveground biomass, and biomass allocation of C. microphylla were examined. Pretreatment measurements were made in 2005 and the first prescribed burning was in 2006 with the second repeat burning in 2007. Results showed that: 1) C. microphylla may have been an expanding population in our experimental plots. Of the 6,588 individual shrubs examined, 30% were small-crown size shrubs (0-50 cm), 49% were mid-crown size shrubs (50-150 cm), and only 21% were large crown size shrubs (>150 cm); 2) At the plant community level, growth of C. microphylla was significantly inhibited by prescribed burning. The aboveground net primary productivity (ANPP) of C. microphylla was reduced by 27% for 1-year burning and by 66% for the 2-year repeat burning, compared with the initial ANPP before treatment; 3) Burning significantly enhanced the current year stem density of C. microphylla, increased biomass allocation to new stems, reduced biomass allocation to leaves, and shifted stem/leaf ratios from 1∶4.4 to 1∶1.1; 4) At the individual bunch level, the impact of burning on aboveground biomass production of C. microphylla varied with crown size. The largest reduction in aboveground biomass was found in the small-crown size class, in which the average aboveground biomass decreased by 57% for the 1-year burning and by 60% for the 2-year repeat burning. Results from this study suggest that prescribed burning is an effective approach for controlling the growth and encroachment of C. microphylla into the Inner Mongolia grasslands.

CLC Number:

S812

LIN Yan, BAI Yong-fei. Responses of aboveground net primary production and population structure of Caragana microphylla to prescribed burning in a typical steppe of Inner Mongolia[J]. Acta Prataculturae Sinica, 2010, 19(5): 170-178.

References

[1] Schlesinger W H, Reynolds J F, Cunningham G L, et al. Biological feedbacks in global desertification[J]. Science, 1990, 247: 1043-1048.
[2] Knight C L, Briggs J M, Nellis M D. Expansion of gallery forest on Konza Prairie Research Natural Area, Kansas, USA[J]. Landscape Ecology, 1994, 9: 117-125.
[3] Archer S. Tree-grass dynamics in a Prosopis thornscrub savanna parkland: Reconstructing the past and predicting the future[J]. Ecoscience, 1995, 2: 83-99.
[4] Briggs J M, Knapp A K, Brock B L. Expansion of woody plants in tallgrass prairie: A fifteen-year study of fire and fire-grazing interactions[J]. American Midland Naturalist, 2002, 147: 287-294.
[5] Heisler J L, Briggs J M, Knapp A K. Long-term patterns of shrub expansion in a C₄-dominated grassland: Fire frequency and the dynamics of shrub cover and abundance[J]. American Journal of Botany, 2003, 90: 423-428.
[6] Scholes R J, Archer S R. Tree-grass interactions in savannas[J]. Annual Review of Ecology and Systematics, 1997, 28: 517-544.
[7] Sturm M, Racine C, Tape K. Climate change: Increasing shrub abundance in the Arctic[J]. Nature, 2001, 411: 546-547.
[8] Briggs J M, Knapp A K, Blair J M, et al. An ecosystem in transition: Causes and consequences of the conversion of mesic grassland to shrubland[J]. Bioscience, 2005, 55: 243-254.
[9] Wright H A. The role and use of fire in the semi-desert grass-shrub type[A]. General Technical Report[C]. Ogden, Utah: USDA Forest Service, 1980: 85.
[10] Pyke G H. Optimal foraging theory: A critical review[J]. Annual Review of Ecology and Systematics, 1984, 15: 523-575.
[11] Bahre C J. A Legacy of Change: Historic Human Impact on Vegetation of the Arizona Borderlands[M]. Tucson: University of Arizona Press, 1991: 231.
[12] Martin S C. Responses of semi-desert grasses and shrubs to fall burning[J]. Journal of Range Management, 1983, 36: 604-610.
[13] McPherson G R. The role of fire in the desert grassland[J]. Renewable Energy Foundation, 1995, 110: 131-151.
[14] Walter H. Ecology of Tropical and Subtropical Vegetation[M]. Edinburgh: Oliver and Boyd, 1971: 207-236.
[15] Bai Y F, Han X G, Wu J G, et al. Ecosystem stability and compensatory effects in the Inner Mongolia grassland[J]. Nature, 2004, 431: 181-184.
[16] 李博,雍世鹏,李忠厚. 锡林河流域植被及其利用[A]. 草原生态系统研究(第三集)[M]. 北京: 科学出版社, 1988: 84-183.
[17] 赵献英,杨彦臣,杨汝蒙. 锡林河流域天然草场的生态地理特征及其展望[A]. 草原生态系统研究(第三集)[M]. 北京: 科学出版社, 1988: 184-226.
[18] 李永宏. 放牧影响下羊草草原和大针茅草原植物多样性的变化[J]. 植物学报, 1993, 35(11): 877-884.
[19] 熊小刚,韩兴国,白永飞,等. 锡林河流域草原小叶锦鸡儿分布增加的趋势、原因和结局[J]. 草业学报, 2003, 12(3): 57-62.
[20] 熊小刚,韩兴国. 内蒙古半干旱草原灌丛化过程中小叶锦鸡儿引起的土壤碳、氮资源的空间异质性分布[J]. 生态学报, 2005, 25(7): 1678-1683.
[21] 孙志蓉,翟明普,王文全,等. 密度对小叶锦鸡儿播种苗生长的影响[J]. 北京林业大学学报, 2007, 29(1): 42-46.
[22] 赵爱芬. 差巴嘎蒿和小叶锦鸡儿根系分布及生长动态的初步研究[J]. 中国草地, 1994, 3: 15-19.
[23] 周海燕,李新荣,樊恒文,等. 极端条件下几种锦鸡儿属灌木的生理特性[J]. 中国沙漠, 2005, 25(2): 182-190.
[24] 阿拉木萨,慈龙骏,杨晓晖,等. 科尔沁沙地不同密度小叶锦鸡儿灌丛水量平和研究[J]. 应用生态学报, 2006, 17(1): 31-35.
[25] 陶林,高洪文,樊奋成. 小叶锦鸡儿根瘤固氮活性的动态变化[J]. 中国草地, 2005, 27(3): 53-56.
[26] 刘方明,郝伟,姜勇. 科尔沁沙地小叶锦鸡儿对土壤有机碳积累的影响[J]. 辽宁工程技术大学学报, 2006, 25(2): 294-296.
[27] 闫德仁,赵春光,齐凯,等. 小叶锦鸡儿灌丛土壤肥力变化的研究[J]. 内蒙古林业科技, 2007, 33(3): 1-4.
[28] 姜恕. 中国科学院内蒙古草原生态系统定位研究站的简历和研究工作概述[A]. 草原生态系统研究(第一集)[M]. 北京: 科学出版社, 1985: 75-82.
[29] 王炜,梁存柱,郝敦元,等. 内蒙古草原退化群落恢复演替的研究(Ⅰ.退化草原的基本特征与恢复演替动力)[J]. 植物生态学报, 1996, 20(5): 449-459.
[30] 周道玮,周以良,郑焕能. 火生态学研究评述[J]. 世界林业研究, 1993, 6: 38-44.
[31] Holechek J, Pieper R D, Herbel C H. Range Management: Principles and Practices. Fifth edition[M]. New Jersey: Pearson Prentice Hall, 2002.
[32] Bond W J, Keeley J E. Fire as a global ‘herbivore’: The ecology and evolution of flammable ecosystems[J]. Trends in Ecology and Evolution, 2005, 20: 387-394.
[33] Erdensaikhan N, Erdentuya M. Fire situation in Mongolia[J]. International Forest Fire News, 2002, 26: 75-83.
[34] Heisler J L, Briggs J M, Knapp A K, et al. Direct and indirect effects of fire on shrub density and aboveground productivity in a mesic grassland[J]. Ecology, 2004, 85: 2245-2257.
[35] Flinn M A, Wein R W. Depth of underground plant organs and theoretical survival during fire[J]. Canadian Journal of Botany, 1977, 55: 2550-2554.
[36] Keeley J E, Keeley M B, Bond W J. Stem demography and post-fire recruitment of a resprouting serotinous conifer[J]. Journal of Vegetation Science, 1999, 10: 69-76.
[37] Hodgkinson K C. Sprouting success of shrubs after fire: Height-dependent relationships for different strategies[J]. Oecologia, 1998, 115: 64-72.
[38] Bond W J, Midgley J J. Ecology of sprouting in woody plants: The persistence niche[J]. Trends in Ecology and Evolution, 2001, 16: 45-51.
[39] Pate J S, Froend R H, Bowen B J, et al. Seedling growth and storage characteristics of seeder and resprouter species of Mediterranean-type ecosystems of south-west Australia[J]. Annals of Botany, 1990, 65: 585-601.
[40] Bell T L, Pate J S, Dixon K W. Relationships between fire response, morphology, root anatomy and starch distribution in south-west Australian Epacridaceae[J]. Annals of Botany, 1996, 77: 357-364.
[41] Bell T L, Ojeda F. Underground starch storage in Erica species of the Cape floristic region: Differences between seeders and resprouters[J]. New Phytologist, 1999, 144: 143-152.
[42] McCarron J K, Knapp A K. C₃ shrub expansion in a C₄ grassland: Positive post-fire responses in resouces and shoot growth[J]. American Journal of Botany, 2003, 90: 1496-1501.
[43] Lett M S, Knapp A K. Consequences of shrub expansion in mesic grassland: Resource alterations and graminoid responses[J]. Journal of Vegetation Science, 2003, 14: 487-496.
[44] 左万庆,王玉辉,王风玉,等. 围栏封育措施对退化羊草草原植物群落特征影响研究[J]. 草业学报, 2009, 18(3): 12-19.
[45] 呼格吉勒图,杨劼,宝音陶格涛,等. 不同干扰对典型草原群落物种多样性和生物量的影响[J]. 草业学报, 2009, 18(3): 6-11.
[46] 单贵莲,徐柱,宁发,等. 围封年限对典型草原植被与土壤特征的影响[J]. 草业学报, 2009, 18(2): 3-10.
[47] 刘桂霞,龚玉梅,韩建国. 草地空斑对种苗建植影响的研究进展[J]. 草业科学, 2008, 25(2): 110-115.
[48] Archibald S, Bond W J. Growing tall vs growing wide: Tree architecture and allometry of Acacia karroo in forest, savanna, and arid environments[J]. Oikos, 2003, 102: 3-14.
[49] Meyer K M, Ward D, Moustakas A, et al. Big is not better: Small Acacia mellifera shrubs are more vital after fire[J]. African Journal of Ecology, 2005, 43: 131-136.