Experimental study on growth of Hydrilla verticillata under different concentrations of bicarbonate and its implication
- PDF / 1,491,829 Bytes
- 9 Pages / 595.276 x 790.866 pts Page_size
- 51 Downloads / 203 Views
ORIGINAL ARTICLE
Experimental study on growth of Hydrilla verticillata under different concentrations of bicarbonate and its implication in karst aquatic ecosystem Pei Wang1,2 · Xinrui Zhang3 · Dewei Wang4 · Zhenbin Wu1 · Jianhua Cao2 Accepted: 3 July 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract Bicarbonate (HCO3−) is one of the dominant carbon forms in the aquatic ecosystem and carbon cycle in karst areas. Recent studies have focused on the H CO3− utilization by aquatic plants to assess karst carbon sink at a watershed scale. However, the predominated researches inadequately address the effects on growth of submerged plants in various H CO3− conditions and how the submerged plants affect the karst carbon cycle. Here, H. verticillata was selected as a research object in different HCO3− concentrations. Plant morphology and water chemistry were analyzed to comparatively study the growth strategy and carbon utilization of submerged plants under various HCO3− conditions. The results show that the HCO3− aquatic environment can remarkably promote the growth of H. verticillata in terms of biomass, apical shoots, lateral shoots, and root production. The optimum concentration on biomass accumulation and lateral shoots growth is 4 mmol L−1; while, it is 8 mmol L−1 for the apical growth. But overall, the biomass accumulation is one order of magnitude higher than that in the control group. Despite the abundant dissolved inorganic carbon can significantly stimulate the growth of submerged plants, the respiration of H. verticillata suffers a certain inhabitation when the HCO3− concentration exceeds 4 mmol L−1. In karst aquatic environment, the existing HCO3− not only promotes the growth of submerged plants by means of supplying abundant dissolved inorganic carbon but also creates an alkaline water environment to buffer C O2 from the atmosphere. As a consequence, the presence of submerged plants has greatly enhanced the stability of karst carbon sink. Keywords Karst aquatic ecosystem · Bicarbonate · Submerged plants · Karst carbon sink
Introduction
* Zhenbin Wu [email protected] * Jianhua Cao jianhuacao‑[email protected] 1
State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
2
International Research Center on Karst Under the Auspices of UNESCO, Guilin 541004, China
3
School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, China
4
College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541006, China
Carbonate weathering-related carbon sink has been recognized (Yuan 1993; Falkowski et al. 2000) and received more and more attention in the recent decades (Larson 2011; Curl 2012; Wang et al. 2019). Around the world, carbonate rocks are widely distributed, with an area of 2.2 × 107 km2, about 15% of the terrestrial area on earth (Yuan 1997a), which involves approximately 0.608 Pg C year−1 to carbon dioxide sequestration
Data Loading...
