title: Effects of Simulated Nitrogen Deposition on Soil Respiration in a Populus euphratica Community in the Ebinur Lake Area, a Desert Ecosystem of Northwestern China.
abstract: One of the primary limiting factors for biological activities in desert ecosystems is nitrogen (N). This study therefore examined the effects of N and investigated the responses of an arid ecosystem to global change. We selected the typical desert plant Populus euphratica in a desert ecosystem in the Ebinur Lake area to evaluate the effects of N deposition on desert soil respiration. Three levels of N deposition (0, 37.5 and 112.5 kg·N·ha-1·yr-1) were randomly artificially provided to simulate natural N deposition. Changes in the soil respiration rates were measured from July to September in both 2010 and 2013, after N deposition in April 2010. The different levels of N deposition affected the total soil N, soil organic matter, soil C/N ratio, microorganism number, and microbial community structure and function. However, variable effects were observed over time in relation to changes in the magnitude of N deposition. Simulated high N deposition significantly reduced the soil respiration rate by approximately 23.6±2.5% (P<0.05), whereas low N deposition significantly increased the soil respiration rate by approximately 66.7±2.7% (P<0.05). These differences were clearer in the final growth stage (September). The different levels of N deposition had little effect on soil moisture, whereas N deposition significantly increased the soil temperature in the 0-5 cm layer (P<0.05). These results suggest that in the desert ecosystem of the Ebinur Lake area, N deposition indirectly changes the soil respiration rate by altering soil properties.
authors.affiliation: Xinjiang Key Laboratory of Oasis Ecology, Xinjiang University, Urumqi, Xinjiang, China; College of Resources and Environment Science, Xinjiang University, Urumqi, Xinjiang, China.
authors.forename: Xuemin
authors.initials: X
authors.lastname: He
authors.affiliation: Xinjiang Key Laboratory of Oasis Ecology, Xinjiang University, Urumqi, Xinjiang, China; College of Resources and Environment Science, Xinjiang University, Urumqi, Xinjiang, China.
authors.forename: Guanghui
authors.initials: G
authors.lastname: Lv
authors.affiliation: Xinjiang Key Laboratory of Oasis Ecology, Xinjiang University, Urumqi, Xinjiang, China; College of Resources and Environment Science, Xinjiang University, Urumqi, Xinjiang, China; Xinjiang Academy of Environmental Protection Science, Xinjiang Department of Environmental Protection, Urumqi, Xinjiang, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Qin
authors.affiliation: Xinjiang Key Laboratory of Oasis Ecology, Xinjiang University, Urumqi, Xinjiang, China; College of Resources and Environment Science, Xinjiang University, Urumqi, Xinjiang, China.
authors.forename: Shunli
authors.initials: S
authors.lastname: Chang
authors.affiliation: Xinjiang Key Laboratory of Oasis Ecology, Xinjiang University, Urumqi, Xinjiang, China; College of Resources and Environment Science, Xinjiang University, Urumqi, Xinjiang, China.
authors.forename: Min
authors.initials: M
authors.lastname: Yang
authors.affiliation: Xinjiang Key Laboratory of Oasis Ecology, Xinjiang University, Urumqi, Xinjiang, China; College of Resources and Environment Science, Xinjiang University, Urumqi, Xinjiang, China.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Yang
authors.affiliation: College of Resources and Environment Science, Xinjiang University, Urumqi, Xinjiang, China.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Yang
mesh_terms: D002244:Carbon / Q000737:chemistry / Q000378:metabolism; D002681:China; D003889:Desert Climate; D017753:Ecosystem; D060106:Lakes / Q000737:chemistry; D009584:Nitrogen / Q000737:chemistry / Q000378:metabolism*; D032107:Populus / Q000378:metabolism*; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D012987:Soil; D014867:Water; D002244:Carbon; D009584:Nitrogen