Differential photosynthetic and morphological adaptations to low light affect depth distribution of two submersed macrophytes in lakes.
To evaluate the relative importance of photosynthetic versus morphological adaptations of submersed macrophytes to low light intensity in lakes, rapid light curves (RLCs), morphological parameters, relative growth rate (RGR), clonal reproduction and abundance of two submersed macrophytes (Potamogeton maackianus and Vallisneria natans) were examined under 2.8%, 7.1%, 17.1% and 39.5% ambient light in a field and outdoor experimental study. The plants increased their initial slope of RLCs (α) and decreased their minimum saturating irradiance (Ek) and maximum relative electron transport rate (ETRm) of RLCs under low light stress, but V. natans was more sensitive in RLCs than P. maackianus. Accordingly, the RGR, plant height and abundance of P. maackianus were higher in the high light regimes (shallow water) but lower in the low light regimes than those of V. natans. At the 2.8% ambient light, V. natans produced ramets and thus fulfilled its population expansion, in contrast to P. maackianus. The results revealed that P. maackianus as a canopy-former mainly elongated its shoot length towards the water surface to compensate for the low light conditions, however, it became limited in severe low light stress conditions. V. natans as a rosette adapted to low light stress mainly through photosynthetic adjustments and superior to severely low light than shoot elongation.
Donghu Experimental Station of Lake Ecosystems, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan, 430072, China.|University of Chinese Academy of Sciences, Beijing 100049, China.
Jianfeng
J
Chen
Donghu Experimental Station of Lake Ecosystems, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan, 430072, China.|Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang City Belt, Anhui Province; College of Life Sciences, Anhui Normal University, Wuhu, 241000, China.
Te
T
Cao
Donghu Experimental Station of Lake Ecosystems, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan, 430072, China.|Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang City Belt, Anhui Province; College of Life Sciences, Anhui Normal University, Wuhu, 241000, China.
Xiaolin
X
Zhang
Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang City Belt, Anhui Province; College of Life Sciences, Anhui Normal University, Wuhu, 241000, China.
Yilong
Y
Xi
Donghu Experimental Station of Lake Ecosystems, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan, 430072, China.|Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang City Belt, Anhui Province; College of Life Sciences, Anhui Normal University, Wuhu, 241000, China.
Leyi
L
Ni
Department of Bioscience and Arctic Research Centre, Aarhus University, Denmark.|Sino-Danish Center for Education and Research, University of Chinese Academy of Sciences, Beijing 100049, China.
Erik
E
Jeppesen
Mar Pollut Bull. 2003 Dec;46(12):1523-33
14643778
Plant Physiol. 1976 Dec;58(6):761-8
16659762
Science. 2009 May 1;324(5927):636-8
19407202
New Phytol. 2011 Sep;191(4):1141-9
21585390
Oecologia. 1979 Jan;40(3):273-286
28309611