Soil nutrients in relation to vertical roots distribution in the riparian zone of Three Gorges Reservoir, China
- 65 Downloads
Since the impoundment of the Three Gorges Reservoir (TGR), the riparian zone has been subjected to numerous environmental changes. This study was conducted to recognize the distribution of grass roots and its impacts on soil nutrients in the water level fluctuation zone of TGR. Roots of four predominant herbaceous plants in the study area, specifically, Cynodon dactylon, Hemarthria altissima, Hemarthria compressa, and Paspalum paspaloides, and their corresponding relation with soil nutrient contents were investigated. Root surface area density was determined with WinRHIZO, and the relationships of root distribution with soil depths and soil nutrient contents were studied. The results indicates that most roots are distributed in the top soil layer of 0–10 cm. Estimated root surface area density for the selected grass species ranges from 0.16 to 13.44 cm2/cm3, and decreases exponentially with an increase in soil depth. Soil organic matter and total nitrogen contents are significantly lower on bare control area than the corresponding values on the grasslands. Total nutrient contents on grasslands of C. dactylon and H. compressa are higher than those of other grass areas. Root length density and root surface area density are significantly correlated with soil organic matter and total nitrogen content for the four grasslands. The present results suggests that plant roots have significant effects on the distribution of soil nutrients in soil profiles in the riparian zone along the TGR. Nevertheless, additional investigations are needed to reveal the specific interactions between plant roots distribution, soil nutrients and water level fluctuations.
KeywordsRoots distribution Soil nutrients Water level fluctuations Riparian zone Root surface area density Root length density
Unable to display preview. Download preview PDF.
Financial support for this study was jointly provided by the National Natural Science Foundation of China (Grant Nos. 41601296, 41571278 and 41771321), China Postdoctoral Science Foundation (Grant No. 2016M592720), Applied Basic Research Foundation of Yunnan Province (Grant No. 2016FD011), and Sichuan Science and Technology Program (2018SZ0132). The authors are thankful to all persons involved in the field investigation and data preparation of this project.
- Bao YH, He XB, Wei J, et al. (2012) Soil erosion under different land uses in the riparian zone of the Three Gorges Reservoir, China. Erosion and Sediment Yields in the Changing Environment 198–201.Google Scholar
- Bao YH, Nan HW, He XB, et al. (2010) Sedimentation in the riparian zone of the Three Gorges Reservoir, China. Sediment Dynamics for a Changing Future. IAHS, Poland. pp 224–228.Google Scholar
- FAO (2016) Grassland Index, A searchable catalogue of grass and forage legumes, Rome, Italy.Google Scholar
- Han FP, Zheng JY, Zhang XC (2009) Plant root system distribution and its effect on soil nutrient on slope land converted from farmland in the Loess Plateau. Transactions of the Chinese Society of Agricultural Engineering 25(2): 50–55. (In Chinese)Google Scholar
- He YR (2003) Purple soil in China (2). Science Press, Beijing, China. (In Chinese)Google Scholar
- Li J, He BH, Chen Y, et al. (2013a) Root distribution features of typical herb plants for slope protection and their effects on soil shear strength. Transactions of the Chinese Society of Agricultural Engineering 29(10): 144–152. (In Chinese) https://doi.org/10.3969/j.issn.1002-6819.2013.10.020 Google Scholar
- Sun BX, Sylvia MP (2006) Poaceae, Flora of China. Science Press, Beijing and Missouri Botanical Garden Press, St Louis, USA. pp. 482–493 + 640–642.Google Scholar
- Tan KH (2005) Soil sampling, preparation and analysis. CRC press, Boca Raton, Florida, USA. pp 342–343.Google Scholar
- Wang Q, Yuan XZ, Liu H (2014). Influence of the three Gorges reservoir on the vegetation of its drawdown area: effects of water submersion and temperature on seed germination of Xanthium sibiricum (Compositae). Polish Journal of Ecology 62(1): 25–36. https://doi.org/10.3161/104.062.0104 CrossRefGoogle Scholar
- Wang XR, Cheng RM, Xiao WF, et al. (2010) Soil nutrient characteristics in juvenile water-level-fluctuating zone of Three Gorges Reservoir. Chinese Journal of Ecology 29(2): 281–289. (In Chinese with English Abstact)Google Scholar
- Yang F, Liu WW, Wang J, et al. (2012) Riparian vegetation’s responses to the new hydrological regimes from the Three Gorges Project: Clues to revegetation in reservoir water-levelfluctuation zone. Acta Ecologica Sinica 32(2): 89–98. https://doi.org/10.1016/j.chnaes.2012.02.004 CrossRefGoogle Scholar
- Yang F, Wang Y, Chan ZL (2015). Review of environmental conditions in the water level fluctuation zone: Perspectives on riparian vegetation engineering in the Three Gorges Reservoir. Aquatic Ecosystem Health & Management 18(2): 240–249. https://doi.org/10.1080/14634988.2015.1040332 CrossRefGoogle Scholar
- Yang JH (2008) Soil agricultural chemistry analysis and environmental monitoring. China Land Press, Beijing. p 382.Google Scholar
- Ye C, Cheng XL, Zhang QF (2014) Recovery Approach Affects Soil Quality in the Water Level Fluctuation Zone of the Three Gorges Reservoir, China: Implications for Revegetation. Environmental Science and Pollution Research 21(3): 2018–2031. https://doi.org/10.1007/s11356-013-2128-5 CrossRefGoogle Scholar
- Ye C, Li SY, Zhan YL, et al. (2013a) Assessing heavy metal pollution in the water level fluctuation zone of China's Three Gorges Reservoir using geochemical and soil microbial approaches. Environmental monitoring and assessment 185(1): 231–240. https://doi.org/10.1007/s10661-012-2547-7 CrossRefGoogle Scholar
- Ye C, Zhang KR, Deng Q, et al. (2013b) Plant Communities in Relation to Flooding and Soil Characteristics in the Water Level Fluctuation Zone of the Three Gorges Reservoir, China. Environmental Science and Pollution Research 20(3): 1794–1802. https://doi.org/10.1007/s11356-012-1148-x CrossRefGoogle Scholar
- Zhang ZY, Wan CY, Zheng ZW, et al. (2013) Plant community characteristics and their responses to environmental factors in the water level fluctuation zone of the Three Gorges Reservoir in China. Environmental Science and Pollution Research 20(10): 7080–7091. https://doi.org/10.1007/s11356-013-1702-1 CrossRefGoogle Scholar