Soil microbial biomass carbon and nitrogen levels and their controlling factors in alpine grassland， Qinghai-Tibet Plateau

doi:10.11686/cyxb2021161

Abstract

Abstract:

The Qinghai-Tibet Plateau is an important geographically isolated and distinctive ecological zone in China. Soil microbes are important drivers of the biogeochemical cycle. Microorganisms are considered the core content of soil biochemical processes. Hence， exploring the content characteristics of soil microbial biomass carbon and nitrogen and their drivers is highly relevant to the understanding of ecosystem function. In this study， a field investigation is conducted in alpine meadows and steppes across the Qinghai-Tibet Plateau. Soil microbial biomass carbon （MBC） and microbial biomass nitrogen （MBN） levels were measured and their relationships with climate， plant community， and soil physicochemical properties were identified. It was found that MBC and MBN contents were higher in alpine meadows than those in alpine steppes. Furthermore， the growing season precipitation （GSP） showed significantly positive correlations with MBC and MBN in both alpine grassland types （P<0.01）， while there were significant negative correlations between the growing season temperature （GST） and MBN in the alpine steppe （P<0.01）. A structural equation model suggested that soil total nitrogen could mediate the MBC and MBN in the alpine meadow， and soil organic carbon may be the key factor of regulating MBC and MBN in the alpine steppe under the influence of growing season precipitation. The findings provide a theoretical framework for the sustainable management of these grassland ecosystems.

Key words: soil microbial biomass carbon, soil microbial biomass nitrogen, alpine meadow, alpine steppe, Qinghai-Tibet Plateau

Yang LI, Yi WANG, Guo-dong HAN, Jian SUN, Ya-feng WANG. Soil microbial biomass carbon and nitrogen levels and their controlling factors in alpine grassland， Qinghai-Tibet Plateau[J]. Acta Prataculturae Sinica, 2022, 31(6): 50-60.

Figures/Tables 6

Fig.1 Characteristics of soil microbial biomass carbon and nitrogen of different grassland types

Fig.2 Correlation among microbial biomass carbon and nitrogen， climate， community diversity and soil physicochemical properties in the alpine meadow （a） and the alpine steppe （b）

Fig.3 The relationship between soil microbial biomass carbon/nitrogen and climate factors after ln transformation

Table 1 Regression and correlation analysis between microbial biomass carbon and nitrogen and climate factors in different grassland types

草地类型Types	微生物量Microbial index	气候Climate factors	斜率Slope	截距Intercept	R²	P
高寒草甸Alpine meadow	MBC	GSP	1.55	-3.08	0.49	<0.01
	MBC	GST	-0.91	8.02	0.03	0.24
	MBN	GSP	1.36	-3.16	0.50	<0.01
	MBN	GST	-0.44	5.82	0.01	0.51
高寒草原Alpine steppe	MBC	GSP	1.87	-4.91	0.44	<0.01
	MBC	GST	-1.60	8.51	0.06	0.05
	MBN	GSP	1.42	-3.47	0.35	<0.01
	MBN	GST	-2.05	8.56	0.14	<0.01

Fig.4 Principal component analysis of soil physicochemical properties and plant community characteristics

Fig.5 Effects of climate， plant community and key factors on soil microbial biomass carbon （MBC） and nitrogen （MBN） in different grassland types

References 52

1	Zhou L X， Ding M M. Soil microbial characteristics as bioindicators of soil health. Biodiversity Science， 2007， 15（2）： 162-171.
	周丽霞，丁明懋. 土壤微生物学特性对土壤健康的指示作用. 生物多样性， 2007， 15（2）： 162-171.
2	Glassman S I， Weihe C， Li J， et al. Decomposition responses to climate depend on microbial community composition. Proceedings of the National Academy of Sciences of the United States of America， 2018， 115（47）： 11994-11999.
3	Bhatnagar J M， Peay K G， Treseder K K. Litter chemistry influences decomposition through activity of specific microbial functional guilds. Ecological Monographs， 2018， 88（3）： 1-16.
4	Powlson D S， Prookes P C， Christensen B T. Measurement of soil microbial biomass provides an early indication of changes in total soil organic matter due to straw incorporation. Soil Biology & Biochemistry， 1987， 19（2）： 159-164.
5	He Z L， Yang X E， Baligar V C， et al. Microbiological and biochemical indexing systems for assessing quality of acid soils. Advances in Agronomy， 2003， 78： 89-138.
6	Zhang D X， Han Z Q， Li D P， et al.Effects of returning maize straw into field on dynamic change of soil microbial biomass C， N and P under different promoted decay condition. Chinese Journal of Applied Ecology， 2005， 16（10）： 1903-1908.
	张电学，韩志卿，李东坡，等. 不同促腐条件下秸秆还田对土壤微生物量碳氮磷动态变化的影响. 应用生态学报， 2005， 16（10）： 1903-1908.
7	Lin X G. Principles and methods of soil microbiology research. Beijing： Higher Education Press， 2010.
	林先贵. 土壤微生物研究原理与方法. 北京：高等教育出版社， 2010.
8	He Y T， Dong Y S， Qi Y C， et al. Advances in researches on soil microbial biomass of grassland ecosystems and its influencing factors. Progress in Geography， 2010， 29（11）： 1350-1359.
	何亚婷，董云社，齐玉春，等. 草地生态系统土壤微生物量及其影响因子研究进展. 地理科学进展， 2010， 29（11）： 1350-1359.
9	Qi Y C， Dong Y S， Geng Y B， et al. The progress in the carbon cycle researches in grassland ecosystem in China. Progress in Geography， 2003， 22（4）： 342-352.
	齐玉春，董云社，耿元波，等. 我国草地生态系统碳循环研究进展. 地理科学进展， 2003， 22（4）： 342-352.
10	Yao T， Ma L P， Zhang D G. Research progress on microbiological ecology of rangeland in China. Pratacultural Science， 2005， 22（11）： 5-11.
	姚拓，马丽萍，张德罡. 我国草地土壤微生物生态研究进展及浅评. 草业科学， 2005， 22（11）： 5-11.
11	Zhang W， Parker K M， Luo Y， et al. Soil microbial responses to experimental warming and clipping in a tallgrass prairie. Global Change Biology， 2010， 11（2）： 266-277.
12	Potthoff M， Steenwerth K L， Jackson L E， et al. Soil microbial community composition as affected by restoration practices in California grassland. Soil Biology & Biochemistry， 2006， 38（7）： 1851-1860.
13	Griffiths R I， Thomson B C， James P， et al. The bacterial biogeography of British soils. Environmental Microbiology， 2011， 13（6）： 1642-1654.
14	Garcia-Pichel F， Loza V， Marusenko Y， et al. Temperature drives the continental-scale distribution of key microbes in topsoil communities. Science， 2013， 340（6140）： 1574-1577.
15	Curd E E， Martiny J， Li H， et al. Bacterial diversity is positively correlated with soil heterogeneity. Ecosphere， 2018， 9（1）： 1-16.
16	Nemergut D R， Schmidt S K， Fukami T， et al. Patterns and processes of microbial community assembly. Microbiology & Molecular Biology Reviews， 2013， 77（3）： 342-356.
17	Liu B R. Changes in soil microbial biomass carbon and nitrogen under typical plant communies along an altitud communies along an altitudinal gradient in east side of Helan Mountain. Ecology and Environmental Sciences， 2010， 19（4）： 883-888.
	刘秉儒. 贺兰山东坡典型植物群落土壤微生物量碳、氮沿海拔梯度的变化特征.生态环境学报， 2010， 19（4）： 883-888.
18	Zhang L H， Xie Z K， Zhao R F， et al. Plant， microbial community and soil property responses to an experimental precipitation gradient in a desert grassland. Applied Soil Ecology， 2018， 127： 87-95.
19	Xue K， Zhang B， Zhou S T， et al. Soil microbial communities in alpine grasslands on the Tibetan Plateau and their influencing factors. Chinese Science Bulletin， 2019， 64（27）： 2915-2927.
	薛凯，张彪，周姝彤，等. 青藏高原高寒草地土壤微生物群落及影响因子. 科学通报， 2019， 64（27）： 2915-2927.
20	Guo J X， Zhu T C， Ma W M， et al. The study relationship between microorganisms and ecology environment in Leymus chinesis grassland. Acta Agrestia Sinica， 1996， 4（4）： 240-245.
	郭继勋，祝廷成，马文明，等. 东北羊草草原土壤微生物与生态环境的关系. 草地学报， 1996， 4（4）： 240-245.
21	Kang J. Soil microbial biomass carbon and nitrogen in different grassland types on western slopes of the Helan Mountains， China. Lanzhou： Lanzhou University， 2006.
	康健. 贺兰山西坡不同草地类型土壤微生物碳、氮特征. 兰州：兰州大学， 2006.
22	Sun J， Ma B， Lu X. Grazing enhances soil nutrient effects： Trade-offs between aboveground and belowground biomass in alpine grasslands of the Tibetan Plateau. Land Degradation & Development， 2018， 29（2）： 337-348.
23	Yang Y H， Fang J Y， Pan Y D， et al. Aboveground biomass in Tibetan grasslands. Journal of Arid Environments， 2009， 73（1）： 91-95.
24	Liu B Y， Sun J， Liu M， et al. The aridity index governs the variation of vegetation characteristics in alpine grassland， Northern Tibet Plateau. PeerJ， 2019， 7： 1-17.
25	Sun J， Zhou T C， Liu M， et al. Water and heat availability are drivers of the aboveground plant carbon accumulation rate in alpine grasslands on the Tibetan Plateau. Global Ecology and Biogeography， 2020， 29（1）： 50-64.
26	Sun J， Zhang Z C， Dong S K. Adaptive management of alpine grassland ecosystems over Tibetan Plateau. Pratacultural Science， 2019， 36（4）： 933-938.
	孙建，张振超，董世魁. 青藏高原高寒草地生态系统的适应性管理. 草业科学， 2019， 36（4）： 933-938.
27	Zou S， Lv F C. Two special vegetation types in Tibetan Plateau： Alpine grassland and alpine meadow. Geography Teaching， 2016， 2： 4-7， 46.
	邹珊，吕富成. 青藏高原两种特殊的植被类型：高寒草原和高寒草甸. 地理教学， 2016， 2： 4-7， 46.
28	Qin X J， Sun J， Wang X D. Plant coverage is more sensitive than species diversity in indicating the dynamics of the above-ground biomass along a precipitation gradient on the Tibetan Plateau. Ecological Indicators， 2018， 84： 507-514.
29	Sun J， Wang H M. Soil nitrogen and carbon determine the trade-off of the above- and below-ground biomass across alpine grasslands， Tibetan Plateau. Ecological indicators： Integrating， monitoring， assessment and management， 2016， 60： 1070-1076.
30	Wang Y， Sun J， Ye C C， et al. Climatic factors drive the aboveground ecosystem functions of alpine grassland via soil microbial biomass nitrogen on Qingzang Plateau. Chinese Journal of Plant Ecology， 2021， 45（5）： 434-443.
	王毅，孙建，叶冲冲，等. 气候因子通过土壤微生物生物量氮促进青藏高原高寒草地地上生态系统功能. 植物生态学报， 2021， 45（5）： 434-443.
31	Li S Y， Sun J， Wang Y， et al. Characteristics of soil enzyme activities in different degraded gradient grasslands on the Tibetan Plateau. Pratacultural Science， 2020， 37（12）： 2389-2402.
	李邵宇，孙建，王毅，等. 青藏高原不同退化梯度草地土壤酶活性特征. 草业科学， 2020， 37（12）： 2389-2402.
32	Zhou G L， Cheng Y X， Ma Q Q， et al. Effects of grazing intensity on community structure and the soil’s physical and chemical properties in an alpine meadow on the Eastern Qinghai-Tibet Plateau. Pratacultural Science， 2019， 36（4）： 1022-1031， 918.
	周国利，程云湘，马青青，等. 牦牛放牧强度对青藏高原东缘高寒草甸群落结构与土壤理化性质的影响. 草业科学， 2019， 36（4）： 1022-1031， 918.
33	Chen Z Y， Xie Y X， Liu M. Responses of aboveground biomass and species richness to environmental factors in a fenced alpine grassland. Pratacultural Science， 2019， 36（4）： 1000-1009.
	陈智勇，谢迎新，刘苗. 围栏封育高寒草地植物地上生物量和物种多样性对关键调控因子的响应. 草业科学， 2019， 36（4）： 1000-1009.
34	Bao S D. Soil and agricultural chemistry analysis. Beijing： China Agriculture Press， 2000.
	鲍士旦. 土壤农化分析. 北京：中国农业出版社， 2000.
35	Zhang Y， Ni J P， Zhou C， et al. Effects of configuration mode of crop-mulberry system in purple arid hillside field on SMBC and SMBN in the Three Gorges Reservoir. Chinese Journal of Eco-Agriculture， 2014， 22（7）： 766-773.
	张洋，倪九派，周川，等. 三峡库区紫色土旱坡地桑树配置模式对土壤微生物生物量碳氮的影响. 中国生态农业学报， 2014， 22（7）： 766-773.
36	Qu C C， Chen X M， Han Z Q， et al. Effects of bioorganic fertilizer application on soil physical properties and microbial biomass carbon and nitrogen in fluvoaquic soil. Bulletin of Soil and Water Conservation， 2018， 38（5）： 70-76.
	曲成闯，陈效民，韩召强，等. 生物有机肥对潮土物理性状及微生物量碳、氮的影响. 水土保持通报， 2018， 38（5）： 70-76.
37	Deng J， Zhang D， Zhang W， et al. Carbon， nitrogen， and phosphorus stoichiometry and homeostasis characteristics of leaves， soil， and microbial biomass of Robinia pseudoacacia forests in the Loess Hilly Region of China. Acta Ecologica Sinica， 2019， 39（15）： 5527-5535.
	邓健，张丹，张伟，等. 黄土丘陵区刺槐叶片-土壤-微生物碳氮磷化学计量学及其稳态性特征. 生态学报， 2019， 39（15）： 5527-5535.
38	Li X Z， Qu Q H. Soil microbial biomass carbon and nitrogen in Mongolian grassland. Acta Pedologica Sinica， 2002， 39（1）： 91-98.
	李香真，曲秋皓. 蒙古高原草原土壤微生物量碳氮特征. 土壤学报， 2002， 39（1）： 91-98.
39	Sapkota M， Young J， Slaughter L， et al. Soil microbial biomass and composition from urban landscapes in a semiarid climate. Applied Soil Ecology， 2021， 158（1）： 103810.
40	Wu J G， Ai L. Soil microbial activity and biomass C and N content in three typical ecosystems in Qi Lian mountains， China. Chinese Journal of Plant Ecology， 2008， 32（2）： 465-476.
	吴建国，艾丽. 祁连山3种典型生态系统土壤微生物活性和生物量碳氮含量. 植物生态学报， 2008， 32（2）： 465-476.
41	Wei W D， Liu Y H. Characteristics analysis of soil microbial biomass carbon on degradated alpine grasslands. Acta Agriculturae Boreali-Occidentalis Sinica， 2014， 23（2）： 205-210.
	魏卫东，刘育红. 不同退化程度高寒草地土壤微生物量碳特征分析. 西北农业学报， 2014， 23（2）： 205-210.
42	Jiang Y M， Shi S L， Tian Y L， et al. Characteristics of soil microorganism and soil enzyme activities in alpine meadows under different degress of degrad ation. Journal of Soil and Water Conservation， 2017， 31（3）： 244-249.
	蒋永梅，师尚礼，田永亮，等. 高寒草地不同退化程度下土壤微生物及土壤酶活性变化特征. 水土保持学报， 2017， 31（3）： 244-249.
43	Duckworth J， Jager T， Ashauer R. Automated， high-throughput measurement of size and growth curves of small organisms in well plates. Scientific Reports， 2019， 9（1）： 17595-17599.
44	Yang T， Adams J M， Shi Y， et al. Soil fungal diversity in natural grasslands of the Tibetan Plateau： Associations with plant diversity and productivity. New Phytologist， 2017， 215（2）： 756-765.
45	Niu S L， Wu M Y， Han Y， et al. Water-mediated responses of ecosystem carbon fluxes to climatic change in a temperate steppe. The New Phytologist， 2007， 177（1）： 209-219.
46	Xu M P， Ren C J， Zhang W， et al. Responses mechanism of C∶N∶P stoichiometry of soil microbial biomass and soil enzymes to climate change. Chinese Journal of Applied Ecology， 2018， 29（7）： 2445-2454.
	许淼平，任成杰，张伟，等. 土壤微生物生物量碳氮磷与土壤酶化学计量对气候变化的响应机制. 应用生态学报， 2018， 29（7）： 2445-2454.
47	Li R， Song W F. Factors affecting soil microbial biomass carbon in Hani terraced ecosystem. Acta Ecologica Sinica， 2020， 40（17）： 6223-6232.
	李荣，宋维峰. 哈尼梯田生态系统土壤微生物量碳的影响因素. 生态学报， 2020， 40（17）： 6223-6232.
48	Jackson R B. Belowground consequences of vegetation change and their treatment in models. Ecological Applications， 2000， 10（2）： 470-483.
49	Wu L K， Lin X M， Lin W X. Advances and perspective in research on plant-soil-microbe interactions mediated by root exudates. Chinese Journal of Plant Ecology， 2014， 38（3）： 298-310.
	吴林坤，林向民，林文雄. 根系分泌物介导下植物-土壤-微生物互作关系研究进展与展望. 植物生态学报， 2014， 38（3）： 298-310.
50	Yu L H， Wang J， Liao L R， et al. Soil microbial biomass， enzyme activities and ecological stoichiometric characteristics and influencing factors along degraded meadows on the Qinghai-Tibet Plateau. Acta Agrestia Sinica， 2020， 28（6）： 1702-1710.
	喻岚晖，王杰，廖李容，等. 青藏高原退化草甸土壤微生物量、酶化学计量学特征及其影响因素. 草地学报， 2020， 28（6）： 1702-1710.
51	Guo Y J. Effects of nitrogen adding on plant community and soil nitrogen supply ability of alpine meadow in Qinghai-Tibet Plateau. Lanzhou： Lanzhou University， 2015.
	郭雅婧. 氮素添加对青藏高原高寒草甸植被和土壤氮素供应能力的影响. 兰州：兰州大学， 2015.
52	Zhang J X， Cao G M. The nitrogen cycle in an alpine meadow ecosystem. Acta Ecologica Sinica， 1999， 19（4）： 509-512.
	张金霞，曹广民. 高寒草甸生态系统氮素循环. 生态学报， 1999， 19（4）： 509-512.

[1]	Yu-zhuo ZHANG, Zhi-gui YANG, Hong-yan YU, Qiang ZHANG, Shu-xia YANG, Ting ZHAO, Hua-hua XU, Bao-ping MENG, Yan-yan LV. Estimating grassland above ground biomass based on the STARFM algorithm and remote sensing data——A case study in the Sangke grassland in Xiahe County， Gansu Province [J]. Acta Prataculturae Sinica, 2022, 31(6): 23-34.
[2]	Xiao-lei ZHOU, Yue-e YAN, Jing ZHANG, Xu-jiao ZHOU, Yong-qin YAN, Fu-qiang YANG, Xue-ping CAO, An ZHAO, Yan-li ZHAO, Jing-yi SU. Vegetation community structure and diversity in a burned area of Picea asperata-Abies fabri forest on different aspects on the northeastern margin of the Qinghai-Tibetan Plateau [J]. Acta Prataculturae Sinica, 2022, 31(5): 144-155.
[3]	Yong-mei LIU, Xing-zhi DONG, Yong-qing LONG, Zhi-mei ZHU, Lei WANG, Xing-hua GE, Fan ZHAO, Jing-zhong LI. Classification of Stellera chamaejasme communities and their relationships with environmental factors in degraded alpine meadow in the central Qilian Mountains， Qinghai Province [J]. Acta Prataculturae Sinica, 2022, 31(4): 1-11.
[4]	Xin LI, Xue WEI, Chang-ting WANG, Xiao REN, Peng-fei WU. Effects of exogenous nutrient addition on alpine meadow soil arthropod communities [J]. Acta Prataculturae Sinica, 2022, 31(4): 155-164.
[5]	Cai-cai SUN, Quan-min DONG, Wen-ting LIU, Bin FENG, Guang SHI, Yu-zhen LIU, Yang YU, Chun-ping ZHANG, Xiao-fang ZHANG, Cai-di LI, Zeng-zeng YANG, Xiao-xia YANG. Effects of grazing modes on the community structure and diversity of soil arthropod in an alpine meadow on the Qinghai-Tibetan Plateau [J]. Acta Prataculturae Sinica, 2022, 31(2): 62-75.
[6]	Li-tao TANG, Rui MAO, Chang-ting WANG, Jie LI, Lei HU, Hong-biao ZI. Effects of nitrogen and phosphorus addition on root characteristics of alpine meadow [J]. Acta Prataculturae Sinica, 2021, 30(9): 105-116.
[7]	Rui WU, Wen-hui LIU, Yong-chao ZHANG, Yan QIN, Xiao-xing WEI, Min-jie LIU. A study of the correlation between seed shattering and agronomic traits of Elymus sibiricus on the Qinghai-Tibetan Plateau [J]. Acta Prataculturae Sinica, 2021, 30(4): 130-139.
[8]	Wei ZHANG, Shu-hua YI, Yu QIN, Dong-hui SHANGGUAN, Yan QIN. Analysis of features and influencing factors of alpine meadow surface temperature based on UAV thermal thermography [J]. Acta Prataculturae Sinica, 2021, 30(3): 15-27.
[9]	Wen-rong LUO, Guo-zheng HU, Ganjurjav H, Qing-zhu GAO, Yan LI, Yi-qing Ge, Yu LI, Shi-cheng HE, Luo-bu DANJIU. Effects of simulated drought on plant phenology and productivity in an alpine meadow in Northern Tibet [J]. Acta Prataculturae Sinica, 2021, 30(2): 82-92.
[10]	GUO Jian-bo, ZHAO Guo-qiang, JIA Shu-gang, DONG Jun-fu, CHEN Long, WANG Shu-ping. Comprehensive evaluation of effects of fertilization on grassland quality index and soil properties in alpine steppe [J]. Acta Prataculturae Sinica, 2020, 29(9): 85-93.
[11]	WANG Xiu-yu, HUANG Xiao-xia, HE Ke-jian, SUN Xiao-neng, LÜZENG Zhe-zhou, ZHANG Yong, ZHU Mei, ZENG Rui-qin. The relationship between plant functional traits and soil physicochemical properties in alpine meadows in Northwestern Yunnan Province, China [J]. Acta Prataculturae Sinica, 2020, 29(8): 6-17.
[12]	XU Tian-wei, ZHAO Jiong-chang, MAO Shao-juan, GENG Yuan-yue, LIU Hong-jin, ZHAO Xin-quan, XU Shi-xiao. Response of plant community structure and biomass to short-term rest grazing in an alpine meadow in Haibei Autonomous Prefecture of Qinghai [J]. Acta Prataculturae Sinica, 2020, 29(4): 1-8.
[13]	YANG Yang, TIAN Li-hua, TIAN Hao-qi, SUN Huai-en, ZHAO Jing-xue, ZHOU Qing-ping. Effect of climate warming on decomposition of plant litter in alpine meadow pastures in Northwestern Sichuan [J]. Acta Prataculturae Sinica, 2020, 29(10): 35-46.
[14]	HOU Shuai-jun, WANG Ying-xin. Summer grazing of red deer effects on plant diversity of alpine grassland on Qilian Mountain [J]. Acta Prataculturae Sinica, 2020, 29(10): 206-210.
[15]	MA Hai-xia, ZHANG De-gang, CHEN Jin, GUO Chun-xiu, DONG Yong-ping, MA Yuan, KANG Yu-kun, CHEN Lu, DU Kai, CHEN Jian-gang. Change in factors influencing soil water holding capacity at microsites along a slope transect in alpine meadow in the eastern Qilian Mountains [J]. Acta Prataculturae Sinica, 2020, 29(1): 28-37.