title: Impacts of the removal of shrubs on the physiological and biochemical characteristics of Syntrichia caninervis Mitt: in a temperate desert.
abstract: Moss crusts play important roles in biological soil crusts biomass and soil surface stabilization. However, because of increasingly intensive human activities, especially grazing, the growth and survival of shrubs are seriously threatened. This study aimed to test whether the presence of shrubs affects the physiological state of the bryophyte Syntrichia caninervis Mitt. in this desert ecosystem. We simulated animal-grazed shrubs at three levels in the Gurbantunggut Desert and compared these simulations to exposed areas, measuring the indicators of growth and stress tolerance exhibited by bryophytes. The results showed that the removal of shrubs significantly decreased chlorophyll fluorescence activity and soluble protein content in S. caninervis, especially under the total shrub removal treatment. The ratio between the total removal of shrubs and other treatments in antioxidative enzymes and in osmotic adjustment substances of S. caninervis exhibited two types of responses. With the exception of malonyldialdehyde (MDA) and superoxide dismutase (SOD), the variables examined fitted as downward parabolic then upward parabolic temporal dynamics. The removal of shrubs is harmful to the survival of S.caninervis. In resource-constrained conditions, SOD is an important antioxidant enzyme that of peroxidase (POD), catalase (CAT) and osmotic adjustment substances, for S. caninervis survival.
authors.affiliation: State Key Laboratory of Earth Surface Processes and Resource Ecology, College of Life Sciences of Beijing Normal University, Beijing 100875, China.|Xinjiang Institute of Ecology and Geography, Key Laboratory of Biogeography and Bioresources in Arid Land, Chinese Academy of Sciences, Urumqi 830011, China.
authors.forename: Ben-Feng
authors.initials: BF
authors.lastname: Yin
authors.affiliation: Xinjiang Institute of Ecology and Geography, Key Laboratory of Biogeography and Bioresources in Arid Land, Chinese Academy of Sciences, Urumqi 830011, China.
authors.forename: Yuan-Ming
authors.initials: YM
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Earth Surface Processes and Resource Ecology, College of Life Sciences of Beijing Normal University, Beijing 100875, China.
authors.forename: An-Ru
authors.initials: AR
authors.lastname: Lou
mesh_terms: D044822:Biodiversity; D044002:Bryophyta / Q000378:metabolism* / Q000502:physiology; D002734:Chlorophyll / Q000378:metabolism; D003889:Desert Climate; D019684:Magnoliopsida / Q000502:physiology; D009997:Osmotic Pressure; D018384:Oxidative Stress; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D002734:Chlorophyll; D013482:Superoxide Dismutase