Influence of Precipitation Change on Soil Respiration in Desert Grassland

被引：2

作者：

Hao L.-Y. ^{[1
]}

Zhang L.-H. ^{[1
]}

Xie Z.-K. ^{[2
]}

Zhao R.-F. ^{[1
]}

Wang J.-F. ^{[1
]}

Guo Y.-F. ^{[1
]}

Gao J.-P. ^{[1
]}

机构：

[1] College of Geography and Environmental Science, Northwest Normal University, Lanzhou

[2] Gaolan Comprehensive Experimental Station of Ecology and Agriculture, Northwest Institute of Ecology and Environment and Resources, Chinese Academy of Sciences, Lanzhou

来源：

Huanjing Kexue/Environmental Science | 2021年 / 42卷 / 09期

关键词：

Aboveground biomass; Desert grassland; Precipitation treatment; Soil carbon pool; Soil respiration(SR);

D O I：

10.13227/j.hjkx.202012204

中图分类号：

学科分类号：

摘要：

Global climate change has significantly changed precipitation patterns. Soil respiration (SR), as an important pathway through which CO2 is released from the soil carbon pool into the atmosphere, may affect the carbon cycle process of terrestrial ecosystems and have a feedback effect on global climate change in response to precipitation change. However, at present there is limited understanding of how SR is affected by precipitation change. Field precipitation control experiments were conducted (with -40%, -20%, natural, 20%, and 40% precipitation) on desert grassland in the west of the Loess Plateau, to investigate the influence of precipitation change on SR dynamics and its relationship with soil water content, soil temperature, aboveground biomass, soil organic carbon, microbial biomass carbon, carbon-nitrogen ratio, and other factors. The results show that the diurnal variations of SR under different precipitation treatments were consistent in unimodal and bimodal models over three years. SR showed an increasing trend with added precipitation, relative to the control, and significant differences were observed between the second year (wetter) and the third year (drier) of the precipitation-manipulation experiment, indicating that precipitation changes had a legacy effect on SR. At the same time, SR was lowest under the -40% treatment and highest under the 40% treatment during the wetter year. The negative response of SR to precipitation exclusion treatments was stronger than the positive response to precipitation addition treatments. SR in drier years was significantly higher under precipitation addition treatments than the control, and the positive response of SR to increased precipitation treatment was significantly stronger than that under decreased precipitation treatment. In addition, soil water content, aboveground biomass, soil organic carbon, and carbon-nitrogen ratio were the environmental factors that obviously affected SR and increased with additional precipitation. SR increased with increases in soil water content, aboveground biomass, soil organic carbon, and carbon-nitrogen ratio, but decreased with increases in microbial biomass carbon. Among these factors, soil water content had the highest interpretation rate for SR, indicating that soil water content was the main environmental factor controlling SR in desert grassland. In both wetter and drier years, the amplitude of plant biomass input was lower than the amplitude of SR output under precipitation change, indicating that precipitation change may be unfavorable to soil carbon sequestration, especially in drier years, when precipitation change has a stronger influence on carbon pool output. Therefore, precipitation changes on SR in desert grassland in various dry and wet years may have different influences on the carbon cycle process of ecosystems, thus providing a reference for regional carbon budget assessment. © 2021, Science Press. All right reserved.

引用

页码：4527 / 4537

页数：10

共 46 条

[1] Climate change 2014: impacts, adaptation, and vulnerability. Part a: global and sectoral aspects. Contribution of working group ii to the fifth assessment report of the Intergovernmental Panel on Climate Change, pp. 35-94, (2014)
[2] Kim D G, Vargas R, Bond-Lamberty B, Et al., Effects of soil rewetting and thawing on soil gas fluxes: A review of current literature and suggestions for future research, Biogeosciences, 9, 7, pp. 2459-2483, (2012)
[3] Ahlstrom A, Raupach M R, Schurgers G, Et al., The dominant role of semi-arid ecosystems in the trend and variability of the land CO2 sink, Science, 348, 6237, pp. 895-899, (2015)
[4] Li W, Wang J L, Zhang X J, Et al., Effect of degradation and rebuilding of artificial grasslands on soil respiration and carbon and nitrogen pools on an alpine meadow of the Qinghai-Tibetan Plateau, Ecological Engineering, 111, pp. 134-142, (2018)
[5] Vicca S, Bahn M, Estiarte M, Et al., Can current moisture responses predict soil CO2 efflux under altered precipitation regimes? A synthesis of manipulation experiments, Biogeosciences, 11, 1, pp. 2991-3013, (2014)
[6] Niu F R, Chen J, Xiong P F, Et al., Responses of soil respiration to rainfall pulses in a natural grassland community on the semi-arid Loess Plateau of China, CATENA, 178, pp. 199-208, (2019)
[7] Ge Y Q, Yan Y L, Liang Y, Et al., The effects of nitrogen deposition on soil respiration in an alpine meadow in Northern Tibet, Chinese Journal of Agrometeorology, 40, 4, pp. 214-221, (2019)
[8] Zhang R, Zhao X Y, Zuo X A, Et al., Effect of manipulated precipitation during the growing season on soil respiration in the desert-grasslands in Inner Mongolia, China, CATENA, 176, pp. 73-80, (2019)
[9] Cai Z L, Qiu S P., Seasonal variation of soil respiration and its impact factors in tropical seasonal rainforest in Xishuangbanna, Yunnan, Ecology and Environmental Sciences, 28, 2, pp. 283-290, (2019)
[10] Bao Z Z, Hou Y Y, Zhu X P, Et al., Effect of alternating wetting and drying and simulated nitrogen deposition on soil CO2emission in alpine wetlands of Bayinbulak, Journal of Agro-Environment Science, 37, 3, pp. 598-604, (2018)

← 1 2 3 4 5 →