PMID- 33218805
OWN - NLM
STAT- MEDLINE
DCOM- 20210122
LR  - 20210122
IS  - 1879-1026 (Electronic)
IS  - 0048-9697 (Linking)
VI  - 761
DP  - 2021 Mar 20
TI  - Photosynthetic characteristics of Tamarix chinensis under different groundwater 
      depths in freshwater habitats.
PG  - 143221
LID - S0048-9697(20)36752-8 [pii]
LID - 10.1016/j.scitotenv.2020.143221 [doi]
AB  - Groundwater is the major source of water for Tamarix chinensis growth in the 
      Yellow River Delta (YRD) region, and the groundwater depth (GWD) dramatically 
      influences the physiological activities of T. chinensis. The quantitative 
      response of the photosynthetic physiological process of T. chinensis to the GWD 
      in freshwater habitats remains unclear. In this study, the response 
      characteristics of gas exchange parameters in the leaves of three-year-old T. 
      chinensis seedlings were measured and analyzed at a graded series of seven GWDs 
      (0 m, 0.3 m, 0.6 m, 0.9 m, 1.2 m, 1.5 m and 1.8 m). The GWD thresholds 
      corresponding to drastic changes in the photosynthetic efficiency and the GWDs of 
      several levels of photosynthetic productivity and efficiency were also 
      determined. In the freshwater habitats of the YRD, variations in GWD 
      significantly altered the relative soil water content (RSWC) and thus influenced 
      the photosynthetic efficiency of T. chinensis. RSWC at 0 </= GWD </= 0.9 m and GWD at 
      1.2 m </= GWD </= 1.8 m directly influenced the photosynthetic physiology of T. 
      chinensis. When the GWD was 1.2 m, net photosynthetic rate (P(n)), apparent 
      quantum efficiency and water use efficiency (WUE) values all peaked. Thus, T. 
      chinensis exhibited a high light and water use efficiency, wide ecological 
      amplitude in terms of light, and high photosynthetic capacity. The optimum GWD 
      for photosynthetic carbon assimilation and WUE in T. chinensis was determined to 
      be 1.2 m. At a deep (>/=1.64 m) or shallow (</=0.53 m) GWD, both P(n) and WUE in T. 
      chinensis clearly decreased below the corresponding mean values. The main causes 
      for the reduction in P(n) in these two GWD ranges (</=0.53 m, >/=1.64 m) were 
      stomatal and nonstomatal limitations, respectively. Additionally, a moderate GWD 
      of 1.09-1.25 m corresponded to the "high-productivity and high-efficiency GWD" 
      range, in which T. chinensis displayed a high photosynthetic yield and WUE. 
      Overall, the photosynthetic capacity of T. chinensis shows characteristics of 
      high tolerance to moderate GWDs from 1.09 m to 1.25 m but intolerance at both 
      shallow (</=0.53 m) and deep (>/=1.64 m) GWDs in freshwater habitats.
CI  - Copyright (c) 2020 Elsevier B.V. All rights reserved.
FAU - Xia, Jiangbao
AU  - Xia J
AD  - Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta, 
      Binzhou University, Binzhou 256603, PR China.
FAU - Lang, Ying
AU  - Lang Y
AD  - College of Agriculture and Forestry Science, Linyi University, Linyi 276000, PR 
      China. Electronic address: langying115@163.com.
FAU - Zhao, Qiankun
AU  - Zhao Q
AD  - Linyi Big Data Centre, Linyi 276000, PR China.
FAU - Liu, Ping
AU  - Liu P
AD  - Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta, 
      Binzhou University, Binzhou 256603, PR China.
FAU - Su, Li
AU  - Su L
AD  - Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta, 
      Binzhou University, Binzhou 256603, PR China.
LA  - eng
PT  - Journal Article
DEP - 20201104
PL  - Netherlands
TA  - Sci Total Environ
JT  - The Science of the total environment
JID - 0330500
RN  - 0 (Soil)
RN  - 059QF0KO0R (Water)
SB  - IM
MH  - Ecosystem
MH  - *Groundwater
MH  - Photosynthesis
MH  - Plant Leaves
MH  - Soil
MH  - *Tamaricaceae
MH  - Water
OTO - NOTNLM
OT  - Freshwater wetland
OT  - Groundwater depth
OT  - Photosynthetic efficiency
OT  - Soil water content
OT  - Tamarix chinensis
OT  - Threshold effects
COIS- Declaration of competing interest The authors declare that they have no known 
      competing financial interests or personal relationships that could have appeared 
      to influence the work reported in this paper.
EDAT- 2020/11/22 06:00
MHDA- 2021/01/23 06:00
CRDT- 2020/11/21 05:28
PHST- 2020/06/28 00:00 [received]
PHST- 2020/09/15 00:00 [revised]
PHST- 2020/10/14 00:00 [accepted]
PHST- 2020/11/22 06:00 [pubmed]
PHST- 2021/01/23 06:00 [medline]
PHST- 2020/11/21 05:28 [entrez]
AID - S0048-9697(20)36752-8 [pii]
AID - 10.1016/j.scitotenv.2020.143221 [doi]
PST - ppublish
SO  - Sci Total Environ. 2021 Mar 20;761:143221. doi: 10.1016/j.scitotenv.2020.143221. 
      Epub 2020 Nov 4.