Effects of Different Types of Heavy Metal Pollution on Functional Traits of Invasive Redroot Pigweed and Native Red Amaranth
- 52 Downloads
The differences in functional traits between invasive plant species (invaders hereafter) and natives are believed to be closely associated with whether the former are successful invasion. Meanwhile, variability in the type of heavy metal pollution can alter the growth and physiological performance of invaders. Thus, determination of the potential effects of different types of heavy metal pollution on functional traits of invaders is vital for illuminating the mechanisms supporting the success of invaders. This study aims to address the effects of the separated treatment of Cu, Cd, and the combined treatments of Cu and Cd on functional traits of invasive redroot pigweed (Amaranthus retroflexus L.; pigweed hereafter) and native red amaranth (A. tricolor L.; amaranth hereafter). Pigweed was significantly taller than amaranth under most treatments. The greater height of pigweed may award greater competitive ability for resource acquisition (particularly sunlight). Leaf shape index of pigweed was significantly larger than that of amaranth under all treatments. The larger leaf shape index of pigweed can enhance the efficiency of resource capture (especially sunlight capture) via adjustments to leaf shape and size. Hence, the higher height and leaf shape index of pigweed may facilitate its further invasion process. Heavy metal pollution (especially Cd) poses significant adverse effects on the growth and physiological performance of the two Amaranthus species. This may be because heavy metal pollution, especially Cd, can mediate toxicity on plant species. The combined treatments of Cu and Cd can confer an antagonistic effect on functional traits of the two Amaranthus species compared with the separated treatment of Cu or Cd. The main reason may be the fact that Cd and Cu influence each other’s uptake for plants.
KeywordsAmaranthus retroflexus Heavy metal pollution Invasive plant species Leaf functional traits Resource capture
This study was supported by National Key Research & Development Program of China (2016YFC0502002), Open Science Research Fund of State Key Laboratory of Pollution Control and Resource Reuse (Tongji University), China (PCRRF17015), National Natural Science Foundation of China (31300343), and Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment.
- Gayomba SR, Jung H, Yan J, Danku J, Rutzke MA, Bernal M, Krämer U, Kochian LV, Salt DE, Vatamaniuk OK (2013) The CTR/COPT-dependent copper uptake and SPL7-dependent copper deficiency responses are required for basal cadmium tolerance in A. thaliana. Metallomics 5:1262–1275. https://doi.org/10.1039/C3MT00111C CrossRefGoogle Scholar
- Hang ZH, Wu HP (2016) Zhenjiang yearbook (The first edition). In: Chen J, Liu S (eds) Organized by Zhenjiang municipal people’s government and Writed by Zhenjiang local records office, vol 25. Publishing House of Local Records, Beijing, p 27Google Scholar
- Liu FD, Yang WJ, Wang ZS, Xu Z, Liu H, Zhang M, Liu YH, An SQ, Sun SC (2010) Plant size effects on the relationships among specific leaf area, leaf nutrient content, and photosynthetic capacity in tropical woody species. Acta Oecol 36:149–159. https://doi.org/10.1016/j.actao.2009.11.004 CrossRefGoogle Scholar
- Wang HT, Wang QJ, Cui ZQ, Sun Z, Sun C (2011) Analysis of correlation among heavy metals elements and background value of heavy metal elements in soil of nantong suburb. J Anhui Agric Sci 39:14062–14064 (In Chinese) Google Scholar
- Wang L, Zhang F, Wang CY, Xiao HG, Shi YC, Zhao LL, Du DL (2015) Insights into the ecotoxicological effects of leaf aqueous extract of Solidago canadensis on seed germination and growth of Lactuca sativa under Cu and Cd pollution. Asian J Ecotoxicol 10:203–209. https://doi.org/10.7524/AJE.1673-5897.20141208001 (In Chinese) Google Scholar
- Wang CY, Jiang K, Liu J, Zhou JW, Wu BD (2018b) Moderate and heavy Solidago canadensis L. invasion are associated with decreased taxonomic diversity but increased functional diversity of plant communities in East China. Ecol Eng 112:55–64. https://doi.org/10.1016/j.ecoleng.2017.12.025 CrossRefGoogle Scholar