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干旱区科学  2014, Vol. 6 Issue (4): 423-431    DOI: 10.1007/s40333-014-0063-z
  学术论文 本期目录 | 过刊浏览 | 高级检索 |
Artificial root exudates and soil organic carbon mineralization in a degraded sandy grassland in northern China
YongQing LUO1,2*, XueYong ZHAO1, Olof ANDRÉN1,3, YangChun ZHU1,2, WenDa HUANG1
1 Naiman Desertification and Farmland Research Station of the Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China;
2 University of Chinese Academy of Sciences, Beijing 100049, China;
3 Bjorklundavagen 3, SE-756 46 Uppsala, Sweden
Artificial root exudates and soil organic carbon mineralization in a degraded sandy grassland in northern China
YongQing LUO1,2*, XueYong ZHAO1, Olof ANDRÉN1,3, YangChun ZHU1,2, WenDa HUANG1
1 Naiman Desertification and Farmland Research Station of the Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China;
2 University of Chinese Academy of Sciences, Beijing 100049, China;
3 Bjorklundavagen 3, SE-756 46 Uppsala, Sweden
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摘要 Plant root exudates contain various organic and inorganic components that include glucose, citric and oxalic acid. These components affect rhizosphere microbial and microfaunal activities, but the mechanisms are not fully known. Studies concerned from degraded grassland ecosystems with low soil carbon (C) contents are rare, in spite of the global distribution of grasslands in need of restoration. All these have a high potential for carbon sequestration, with a reduced carbon content due to overutilization. An exudate component that rapidly decomposes will increase soil respiration and CO2 emission, while a component that reduces decomposition of native soil carbon can reduce CO2 emission and actually help sequestering carbon in soil. Therefore, to investigate root exudate effects on rhizosphere activity, citric acid, glucose and oxalic acid (0.6 g C/kg dry soil) were added to soils from three biotopes (grassland, fixed dune and mobile dune) located in Naiman, Horqin Sandy Land, Inner Mongolia, China) and subjected to a 24-day incubation experiment together with a control. The soils were also analyzed for general soil properties. The results show that total respiration without exudate addition was highest in grassland soil, intermediate in fixed dune and lowest in mobile dune soil. However, the proportion of native soil carbon mineralized was highest in mobile dune soil, reflecting the low C/N ratio found there. The exudate effects on CO2-C emissions and other variables differed somewhat between biotopes, but total respiration (including that from the added substrates) was significantly increased in all combinations compared with the control, except for oxalic acid addition to mobile dune soil, which reduced CO2-C emissions from native soil carbon. A small but statistically significant increase in pH by the exudate additions in grassland and fixed dune soil was observed, but there was a major decrease from acid additions to mobile dune soil. In contrast, electrical conductivity decreased in grassland and fixed dune soil and increased in mobile dune. Thus, discrete components of root exudates affected soil environmental conditions differently, and responses to root exudates in soils with low carbon contents can differ from those in normal soils. The results indicate a potential for, e.g., acid root exudates to decrease decomposition rate of soil organic matter in low carbon soils, which is of interest for both soil restoration and carbon sequestration.
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Olof ANDRéN
YongQing LUO
XueYong ZHAO
YangChun ZHU
WenDa HUANG
关键词:  soil enzyme activity  saline soil  Haloxylon ammodendron  Reaumuria soongonica  Salsola passerina  Tamarix rarmosissima    
Abstract: Plant root exudates contain various organic and inorganic components that include glucose, citric and oxalic acid. These components affect rhizosphere microbial and microfaunal activities, but the mechanisms are not fully known. Studies concerned from degraded grassland ecosystems with low soil carbon (C) contents are rare, in spite of the global distribution of grasslands in need of restoration. All these have a high potential for carbon sequestration, with a reduced carbon content due to overutilization. An exudate component that rapidly decomposes will increase soil respiration and CO2 emission, while a component that reduces decomposition of native soil carbon can reduce CO2 emission and actually help sequestering carbon in soil. Therefore, to investigate root exudate effects on rhizosphere activity, citric acid, glucose and oxalic acid (0.6 g C/kg dry soil) were added to soils from three biotopes (grassland, fixed dune and mobile dune) located in Naiman, Horqin Sandy Land, Inner Mongolia, China) and subjected to a 24-day incubation experiment together with a control. The soils were also analyzed for general soil properties. The results show that total respiration without exudate addition was highest in grassland soil, intermediate in fixed dune and lowest in mobile dune soil. However, the proportion of native soil carbon mineralized was highest in mobile dune soil, reflecting the low C/N ratio found there. The exudate effects on CO2-C emissions and other variables differed somewhat between biotopes, but total respiration (including that from the added substrates) was significantly increased in all combinations compared with the control, except for oxalic acid addition to mobile dune soil, which reduced CO2-C emissions from native soil carbon. A small but statistically significant increase in pH by the exudate additions in grassland and fixed dune soil was observed, but there was a major decrease from acid additions to mobile dune soil. In contrast, electrical conductivity decreased in grassland and fixed dune soil and increased in mobile dune. Thus, discrete components of root exudates affected soil environmental conditions differently, and responses to root exudates in soils with low carbon contents can differ from those in normal soils. The results indicate a potential for, e.g., acid root exudates to decrease decomposition rate of soil organic matter in low carbon soils, which is of interest for both soil restoration and carbon sequestration.
Key words:  soil enzyme activity    saline soil    Haloxylon ammodendron    Reaumuria soongonica    Salsola passerina    Tamarix rarmosissima
收稿日期:  2013-10-08      修回日期:  2014-01-26           出版日期:  2014-08-12      发布日期:  2014-02-17      期的出版日期:  2014-08-12
基金资助: 

This work was financially supported by the National Natural Science Foundation of China (41071185, 31170413) and the National Basic Research Program of China (2011BAC07B02). Chinese Academy of Sciences has kindly granted Prof. Olof ANDRÉN a ‘Professorship for Senior International Scientists’ (Y229D91001), which made his participation possible.

通讯作者:  YongQing LUO    E-mail:  luoyongqing8401@sina.com
引用本文:    
YongQing LUO, XueYong ZHAO, Olof ANDRéN, YangChun ZHU, WenDa HUANG. Artificial root exudates and soil organic carbon mineralization in a degraded sandy grassland in northern China[J]. 干旱区科学, 2014, 6(4): 423-431.
YongQing LUO, XueYong ZHAO, Olof ANDRéN, YangChun ZHU, WenDa HUANG. Artificial root exudates and soil organic carbon mineralization in a degraded sandy grassland in northern China. Journal of Arid Land, 2014, 6(4): 423-431.
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Abera G, Wolde-meskel E, Bakken L R. 2012. Carbon and nitrogen mineralization dynamics in different soils of the tropics amended with legume residues and contrasting soil moisture contents. Biology and Fertility of Soils, 48: 51–66.

Andrén O, Zhao X Y, Liu X M. 1994. Climate and litter decomposition in Naiman, Inner Mongolia, China. Ambio, 23: 222–224.

Andrén O, Kirchmann H, Kätterer T, et al. 2008. Visions of a more precise soil biology. European Journal of Soil Science, 59: 380–390.

Chen Y P, Li Y Q, Awada T, et al. 2012. Carbon sequestration in the total and light fraction soil organic matter along a chronosequence in grazing exclosures in a semiarid degraded sandy site in China. Journal of Arid Land, 4: 411–419.

Elhalmouch Y, Benharrat H, Thalouarn P. 2006. Effect of root exudates from different tomato genotypes on broomrape (O. aegyptiaca) seed germination and tubercle development. Crop Protection, 25: 501–507.

Gadkar V, David-Schwartz R, Nagahashi G, et al. 2003. Root exudate of pmi tomato mutant M161 reduces AM fungal proliferation in vitro. FEMS Microbiology Letter, 223: 193–198.

Gärdenäs A I, Ågren G I, Bird J A, et al. 2011. Knowledge gaps in soil carbon and nitrogen interactions–From molecular to global scale. Soil Biology and Biochemistry, 43: 702–717.

Glanville H, Rousk J, Golyshin P, et al. 2012. Mineralization of low molecular weight carbon substrates in soil solution under laboratory and field conditions. Soil Biology and Biochemistry, 48: 88–95.

Gregory P J. 2006. Plant root. Growth, Activity and Interaction with Soil. Oxford: Blackwell Publishing, 216–222.

Hao Z, Wang Q, Christie P, et al. 2007. Allelopathic potential of watermelon tissues and root exudates. Scientia Horticulturae, 112: 315–320.

ISSCAS (Institute of Soil Sciences, Chinese Academy of Sciences). 1978. Physical and Chemical Analysis Methods of Soils. Shanghai: Shanghai Science Technology Press, 7–59.

Khan M A, Cheng Z H, Xiao X M, et al. 2011. Ultrastructural studies of the inhibition effect against Phytophthora capsici of root exudates collected from two garlic cultivars along with their qualitative analysis. Crop Protection, 30: 1149–1155.

Landi L, Valori F, Ascher J, et al. 2006. Root exudate effects on the bacterial communities, CO2 evolution, nitrogen transformations and ATP content of rhizosphere and bulk soils. Soil Biology and Biochemistry, 38: 509–516.

Li F R, Zhang A S, Duan S S, et al. 2005a. Patterns of reproductive allocation in Artemisia halodendron inhabiting two contrasting habitats. Acta Oecologica. 28: 57–64.

Li F R, Wang T, Zhang A S, et al. 2005b. Wind-dispersed seed deposition patterns and seedling recruitment of Artemisia halodendron in a moving sandy land. Annals of Botany, 96: 69–80.

Li Y, Zhao H, Zhao X, et al. 2006. Biomass energy, carbon and nitrogen stores in different habitats along a desertification gradient in the semiarid Horqin Sandy Land. Arid Land Research and Management, 20: 43–60.

Li Y Q, Zhao H L, Zhao X Y, et al. 2005. Characteristics of soil carbon and nitrogen during desertification process in Horqin Sandy Land. Journal of Soil Water Conservation, 19: 73–76.

McGill W B, Figueiredo C T. 1993. Total nitrogen. In: Carter M R. Soil Sampling and Methods of Analysis. Canadian Society of Soil Science. Boca Raton: Lewis Publishers, 201–211.

Nelson D W, Sommers L E. 1982. Total carbon, organic carbon and organic matter. In: Page A L, Miller R H, Keeney D R. Methods of Soil Analysis, 2nd ed. Madison: American Society of Agronomy, 539–577.

Olsen S R, Cole C W, Watanabe F S, et al. 1954. Estimation of available phosphorus in soils by extraction with sodium bicarbonate. U.S. Department of Agriculture. Circular No.: 939.

Ren L, Su S, Yang X, et al. 2008. Intercropping with aerobic rice suppressed Fusarium wilt in watermelon. Soil Biology and Biochemistry, 40: 834–844.

Rukshana F, Butterly C R, Baldock J A, et al. 2011. Model organic compounds differ in their effects on pH changes of two soils differing in initial pH. Biology and Fertility of Soils, 47: 51–62.

Rukshana F, Butterly C R, Baldock J A, et al. 2012. Model organic compounds differ in priming effects on alkalinity release in soils through carbon and nitrogen mineralisation. Soil Biology and Biochemistry, 51: 35–43.

Silvia N, Angelina M Y, Alberto B, et al. 2001. Carbon mineralization in the southern Sonoran Desert. Acta Oecologica, 22: 269–276.

Strickland M S, Wickings K, Bradford M A. 2012. The fate of glucose, a low molecular weight compound of root exudates, in the belowground foodweb of forests and pastures. Soil Biology and Biochemistry, 49: 23–29.

Sturz A V, Christie B R. 2003. Beneficial microbial allelopathies in the root zone: the management of soil quality and plant disease with rhizobacteria. Soil and Tillage Research, 72: 107–123.

Tian L, Dell E, Shi W. 2010. Chemical composition of dissolved organic matter in agroecosystems: correlations with soil enzyme activity and carbon and nitrogen mineralization. Applied Soil Ecology, 46: 426–435.

van Hees P A W, Jones D L, Finlay R, et al. 2005. The carbon we do not see–the impact of low molecular weight compounds on carbon dynamics and respiration in forest soils: a review. Soil Biology and Biochemistry, 37: 1–13.

Yu J Q, Ye S F, Zhang M F, et al. 2003. Effects of root exudates and aqueous root extracts of cucumber (Cucumis sativus) and allelochemicals, on photosynthesis and antioxidant enzymes in cucumber. Biochemical Systematics and Ecology, 31: 129–139.

Zhang T H, Zhao H L, Li S G, et al. 2004. A comparison of different measures for stabilizing moving sand dunes in the Horqin Sandy Land of Inner Mongolia, China. Journal of Arid Environments, 58: 203–214.

Zhou N, Liu P, Wang Z Y, et al. 2011. The effects of rapeseed root exudates on the forms of aluminum in aluminum stressed rhizosphere soil. Crop Protection, 30: 631–636.

Zuo X A, Zhao H L, Zhao X Y, et al. 2008. Vegetation pattern variation, soil degradation and their relationship along a grassland desertification gradient in Horqin Sandy Land, northern China. Environmental Geology, 58: 1227–1237.

Zuo X A, Zhao X Y, Wang S K, et al. 2012a. Influence of dune stabilization on relationship between plant diversity and productivity in Horqin Sand Land, Northern China. Environmental Earth Science, 67: 1547–1556.

Zuo X A, Knops J M H, Zhao X Y, et al. 2012b. Indirect drivers of plant diversity-productivity relationship in semi-arid sandy grasslands. Biogeosciences, 9: 1277–1289.
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