Photosynthetic response of two shrubs to rainfall pulses in desert regions of northwestern China |
| |
Authors: | B Liu W Z Zhao Z J Wen |
| |
Institution: | 1. Linze Inland River Basin Research Station, Key Laboratory of Inland River Ecohydrology, Cold and Arid Regions, Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China 2. School of Mathematics and Statistics, Lanzhou University, Lanzhou, 730000, China
|
| |
Abstract: | Pulses of rainfall are particularly pivotal in controlling plant physiological processes in ecosystems controlled by limited
water, and the response of desert plants to rainfall is a key to understanding the responses of desert ecosystems to global
climatic change. We used a portable photosynthesis system to measure the responses of the diurnal course of photosynthesis,
light-response curves, and CO2-response curves of two desert shrubs (Nitraria sphaerocarpa Maxim. and Calligonum mongolicum Turcz) to a rainfall pulse in a desert-oasis ecotone in northwestern China. The photosynthetic parameters, light- and CO2-response curves differed significantly before and after the rainfall pulse. Their maximum net photosynthetic rate (P
N) values were 23.27 and 32.92 μmol(CO2) m−2 s−1 for N. sphaerocarpa and C. mongolicum, respectively, with corresponding maximum stomatal conductance (g
s) values of 0.47 and 0.39 mol(H2O) m−2 s−1. The P
N of N. sphaerocarpa after the rainfall was 1.65 to 1.75 times the value before rainfall, whereas those of C. mongolicum increased to approximately 2 times the prerainfall value, demonstrating the importance of the desert plants response by improving
their assimilation rate to precipitation patterns under a future climate. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|