Soil respiration and its influencing factors in a desert steppe in northwestern China under changing precipitation regimes

doi:10.17521/cjpe.2022.0176

Abstract

Abstract:

Aims Soil respiration is one of the most critical components of carbon cycle in terrestrial ecosystems. The study on temporal dynamics of soil respiration and its linkage with environmental factors in desert steppes under changing precipitation can provide data supports for a deep understanding of the regulatory mechanisms of key carbon cycling processes in fragile ecosystems.
Methods A field experiment involving five precipitation treatments (50% reduction, 30% reduction, natural, 30% increase, 50% increase) was set up in 2014 in a desert steppe in Ningxia. The temporal dynamics of soil respiration rate were explored during the growing season (from June to October) in 2019, and the relationships between soil respiration rate and soil properties and plant characteristics were analyzed.
Important findings Soil respiration rate showed a seasonal variation of an increasing and a decreasing trend across the growing season, with the maximum values (2.79-5.35 μmol·m^-2·s^-1) occurring in late July or early August. Compared with the natural condition, 30% reduction in precipitation did not result in a significant effect on soil respiration rate, reflecting the adaptability of soil respiration to moderate drought. Overall, 50% reduction in precipitation reduced soil respiration rate, whereas increased precipitation (especially the 30% increase) enhanced soil respiration rate, and this positive effect was especially obvious in the early growing season (June to July). Soil respiration rate had a significantly exponential relationship with soil temperature and a significantly linear relationship with soil water content. Soil physicochemical property had a highly independent explanatory power for soil respiration rate (R² = 0.36), and its effect was highly correlated with soil biological property and plant diversity (R² = 0.31). Precipitation could affect soil respiration rate either directly or indirectly through the influences on soil biological property and plant biomass. The results indicated that a moderate increase in precipitation could accelerate soil respiration by alleviating soil water limitation, stimulating soil enzyme activity, promoting microbial activity and plant growth in the desert steppe, and that an extreme increase in precipitation would lead to a decrease in soil permeability and a hindrance to microbial metabolic activity, thus inhibiting soil respiration.

Key words: changing precipitation pattern, desert steppe, plant community characteristic, soil carbon source, soil property

LI Bing, ZHU Wan-Wan, HAN Cui, YU Hai-Long, HUANG Ju-Ying. Soil respiration and its influencing factors in a desert steppe in northwestern China under changing precipitation regimes[J]. Chin J Plant Ecol, 2023, 47(9): 1310-1321.

Add to citation manager EndNote|Ris|BibTeX

URL: https://www.plant-ecology.com/EN/10.17521/cjpe.2022.0176

https://www.plant-ecology.com/EN/Y2023/V47/I9/1310

Figures/Tables 10

Fig. 1 Monthly precipitation, average air temperature, and average wind speed in the Yanchi station, Ningxia in 2019.

Table 1 Repeated measurement ANOVA of precipitation and measuring time on soil respiration rate in a desert steppe

差异来源 Difference source	df	8:00-10:00	15:00-17:00
降水量处理 Precipitation treatment (α)	4	13.198^**	37.013^**
测定时间 Measuring time (β)	4	24.532^**	37.278^**
降水量处理×测定时间 Interaction of α and β	16	0.520	0.678

Fig. 2 Effects of precipitation change on soil respiration rate from June to October in a desert steppe (mean ± SE). W1, 50% reduction in precipitation; W2, 30% reduction in precipitation; W3, natural precipitation; W4, 30% increase in precipitation; W5, 50% increase in precipitation. Different lowercase letters indicate significant differences among the precipitation treatments under the same measuring time (p < 0.05).

Table 2 Repeated measurement ANOVA of precipitation and measuring time on soil temperature (ST) and soil water content (SWC) in a desert steppe

差异来源 Differences source	df	ST		SWC
差异来源 Differences source	df	8:00-10:00	15:00-17:00	8:00-10:00
降水量处理 Precipitation treatment (α)	4	3.707^*	2.276	27.601^**
测定时间 Measuring time (β)	4	57.317^**	146.775^**	15.003^**
降水量处理×测定时间 Interaction of α and β	16	0.108	0.306	1.879

Fig. 3 Effects of precipitation change on soil temperature from June to October in a desert steppe (mean ± SE). W1, 50% reduction in precipitation; W2, 30% reduction in precipitation; W3, natural precipitation; W4, 30% increase in precipitation; W5, 50% increase in precipitation. Different lowercase letters indicate significant differences among the precipitation treatments under the same measuring time (p < 0.05).

Fig. 4 Effects of precipitation change on soil water content from June to October in a desert steppe (mean ± SE). W1, 50% reduction in precipitation; W2, 30% reduction in precipitation; W3, natural precipitation; W4, 30% increase in precipitation; W5, 50% increase in precipitation. Different lowercase letters indicate significant differences among the precipitation treatments under the same measuring time (p < 0.05).

Table 3 Effects of precipitation change on soil properties and plant characteristics in August in a desert steppe (mean ± SE)

指标 Index	处理 Treatment
指标 Index	W1	W2	W3	W4	W5
pH	8.52 ± 0.05^bc	8.58 ± 0.04^ab	8.43 ± 0.04^c	8.67 ± 0.05^a	8.66 ± 0.04^a
EC	89.97 ± 0.88^a	93.37 ± 2.44^a	128.70 ± 18.49^a	289.67 ± 22.93^a	358.00 ± 38.19^a
SOC	2.96 ± 0.08^b	3.25 ± 0.50^ab	3.34 ± 0.17^ab	3.38 ± 0.24^ab	3.70 ± 0.12^a
TN	0.48 ± 0.00^a	0.49 ± 0.01^a	0.48 ± 0.01^a	0.43 ± 0.02^b	0.43 ± 0.01^b
TP	0.34 ± 0.00^a	0.29 ± 0.00^b	0.27 ± 0.01^c	0.28 ± 0.00^bc	0.27 ± 0.00^c
NO₃^--N	5.50 ± 0.41^a	5.08 ± 0.76^ab	3.28 ± 0.05^b	5.19 ± 0.91^a	5.81 ± 0.42^a
NH₄⁺-N	2.91 ± 0.23^a	3.59 ± 0.68^a	5.44 ± 1.12^a	5.71 ± 1.84^a	5.31 ± 3.34^a
AP	1.56 ± 0.13^a	1.62 ± 0.51^a	1.72 ± 0.28^a	2.14 ± 0.30^a	2.47 ± 0.68^a
SA	318.41 ± 33.75^c	359.39 ± 41.44^bc	381.78 ± 33.90^abc	434.93 ± 36.46^ab	474.67 ± 30.07^a
UA	27.85 ± 3.86^b	30.68 ± 0.67^b	30.95 ± 1.96^b	45.34 ± 4.52^a	45.70 ± 4.82^a
PA	44.58 ± 0.32^bc	40.89 ± 3.01^c	43.88 ± 2.97^bc	49.02 ± 2.42^ab	55.60 ± 1.35^a
MBC	99.05 ± 9.57^ab	77.05 ± 20.59^ab	46.68 ± 14.32^b	100.24 ± 27.02^ab	108.73 ± 8.91^a
MBN	48.97 ± 2.28^a	5.90 ± 0.80^a	7.45 ± 1.74^a	15.10 ± 7.95^a	19.91 ± 8.67^a
MBP	1.76 ± 0.73^b	3.56 ± 0.40^a	1.76 ± 0.76^b	1.14 ± 0.34^b	2.00 ± 0.34^ab
R	5.00 ± 0.58^b	6.67 ± 0.88^ab	6.00 ± 1.00^ab	8.67 ± 1.20^a	8.67 ± 0.88^a
H'	1.13 ± 0.14^c	1.31 ± 0.07^bc	1.49 ± 0.10^ab	1.43 ± 0.02^ab	1.66 ± 0.08^a
E	0.70 ± 0.03^b	0.70 ± 0.06^b	0.86 ± 0.04^a	0.67 ± 0.04^b	0.77 ± 0.00^ab
D	0.43 ± 0.06^a	0.37 ± 0.05^ab	0.27 ± 0.02^bc	0.36 ± 0.04^abc	0.24 ± 0.02^c

Fig. 5 Fitting relationships of soil respiration rate (SR) with soil temperature (T) and water content (W) across the whole growing season in a desert steppe.

Fig. 6 Variation partitioning of soil respiration rate by environmental factor groups in a desert steppe. Values < 0 are not shown. Data in one circle represent the variation individually explained by the environmental factor groups. Data in the overlapped part of circles represent the variation jointly explained by environmental factor groups. X1 group includes soil temperature, water content, pH, organic carbon, nitrate nitrogen, and ammonium nitrogen content. X2 group includes soil sucrase activity and microbial biomass carbon, nitrogen, phosphorus content. X3 group includes Shannon-Wiener diversity index and Pielou evenness index.

Fig. 7 Structural equation model of soil respiration rate and environmental factors under changing precipitation regimes in a desert steppe. CP, precipitation; PB, plant biomass; R, Patrick richness index; SBP, soil biological properties (sucrase activity, urease activity, phosphatase activity, microbial biomass carbon content); SCP, soil chemical property (pH, electrical conductivity, organic carbon, available phosphorus content); SPP, soil physical property (water content and temperature); SR, soil respiration rate. Black solid and dashed arrows indicate significant (p < 0.05) and insignificant (p > 0.05) path, respectively. Numbers on the arrows are normalized path coefficients (*, p < 0.05; **, p < 0.01; ***, p < 0.001). Model fit summary: χ2 = 5.709, p = 0.457, df = 6; comparative fit index (GFI) = 0.998; root mean square error of approximation (RMSEA) = 0.000; standardized root mean square residual (SRMR) = 0.035.

References 50

[1]	Arredondo T, Delgado-Balbuena J, Huber-Sannwald E, García- Moya E, Loescher HW, Aguirre-Gutiérrez C, Rodriguez-Robles U (2018). Does precipitation affects soil respiration of tropical semiarid grasslands with different plant cover types? Agriculture, Ecosystems & Environment, 251, 218-225. DOI URL
[2]	Bao SD (2000). Soil and Agricaltral Chemistry Analysis. 3rd ed. China Agriculture Press, Beijing.
	[鲍士旦 (2000). 土壤农化分析. 3版. 中国农业出版社, 北京.]
[3]	Chang M, Liu B, Martinez-Villalobos C, Ren G, Li S, Zhou T (2020). Changes in extreme precipitation accumulations during the warm season over continental China. Journal of Climate, 33, 10799-10811. DOI URL
[4]	Chen X, Chen HYH (2019). Plant diversity loss reduces soil respiration across terrestrial ecosystems. Global Change Biology, 25, 1482-1492. DOI URL
[5]	Cui H, Zhang YH (2016). Diurnal and seasonal dynamic variation of soil respiration and its influencing factors of different fenced enclosure years in desert steppe. Environmental Science, 37, 1507-1515.
	[崔海, 张亚红 (2016). 不同封育年限荒漠草原土壤呼吸日、季动态变化及其影响因子. 环境科学, 37, 1507-1515.]
[6]	Cui Y, Yan SW, Wu JZ, Luo QH, Lin YM, Wang DJ, Wu CZ (2019). Effects of plant and microbial biomass and enzyme activities on soil respiration in the preliminary stage after the Wenchuan earthquake. Chinese Journal of Applied and Environmental Biology, 25, 215-224.
	[崔羽, 严思维, 吴建召, 罗清虎, 林勇明, 王道杰, 吴承祯 (2019). 汶川地震受损区恢复初期植物与微生物生物量、土壤酶活性对土壤呼吸的影响. 应用与环境生物学报, 25, 215-224.]
[7]	Ding JZ, Lai LM, Zhao XC, Zhu LH, Jiang LH, Zheng YR (2011). Effects of desertification on soil respiration and ecosystem carbon fixation in Mu Us sandy land. Acta Ecologica Sinica, 31, 1594-1603.
	[丁金枝, 来利明, 赵学春, 朱林海, 姜联合, 郑元润 (2011). 荒漠化对毛乌素沙地土壤呼吸及生态系统碳固持的影响. 生态学报, 31, 1594-1603.]
[8]	Dou WQ, Tian LL, Xiao B, Yao XM, Li SL (2022). Responses of respiration rate of moss biocrusts to the manipulation of rainfall amount on the Chinese Loess Plateau. Acta Ecologica Sinica, 42, 1703-1715.
	[窦韦强, 田乐乐, 肖波, 姚小萌, 李胜龙 (2022). 黄土高原藓结皮土壤呼吸速率对降雨量变化的响应. 生态学报, 42, 1703-1715.]
[9]	Fan KK, Li SZ, Chen JQ, Yan YC, Xin XP, Wang X (2022). Spatial heterogeneity analysis of soil respiration in Hulunbuir grassland. Acta Agrestia Sinica, 30, 205-211.
	[范凯凯, 李淑贞, 陈金强, 闫玉春, 辛晓平, 王旭 (2022). 呼伦贝尔草原土壤呼吸作用空间异质性分析. 草地学报, 30, 205-211.] DOI
[10]	Gao MH, Wurenqiqige, Bateer, Mu YH, Wang J, Zhao HR, Meng QT (2016). Influences of grazing on plant community characteristics, soil microorganism and soil enzyme activity. Bulletin of Soil and Water Conservation, 36, 62-65.
	[高明华, 乌仁其其格, 巴特尔, 穆艳红, 王金, 赵慧如, 孟庆涛 (2016). 放牧对植物群落特征和土壤微生物及酶活性的影响. 水土保持通报, 36, 62-65.]
[11]	Guan YS (1986). Soil Enzymes and Their Research Methods. China Agriculture Press, Beijing.
	[关荫松 (1986). 土壤酶及其研究方法. 中国农业出版社, 北京.]
[12]	Guo WZ, Jing CQ, Wang GX, Hou ZX, Zhao WK (2021). Responses of soil respiration and ecosystem respiration to precipitation in desert steppe on the northern slope of Tianshan Mountains. Acta Agrestia Sinica, 29, 2031-2039.
	[郭文章, 井长青, 王公鑫, 侯志雄, 赵苇康 (2021). 天山北坡荒漠草原土壤呼吸和生态系统呼吸对降水的响应. 草地学报, 29, 2031-2039.] DOI
[13]	Guo YP, Li HJ (2022). Response of soil respiration to soil moisture, temperature and vegetation factors in two shrub communities of Tianlong Mountain area. Soil and Fertilizer Sciences in China, (4), 131-139.
	[郭艳萍, 李洪建 (2022). 天龙山灌丛生态系统土壤呼吸对水热和植被因子的响应. 中国土壤与肥料, (4), 131-139.]
[14]	Han D, Li YL, Yang HL, Ning ZY, Zhang ZQ (2021). Effects of simulated temperature increase and change of rainfall frequency on soil respiration in arid and semi-arid areas. Journal of Desert Research, 41, 100-108. DOI
	[韩丹, 李玉霖, 杨红玲, 宁志英, 张子谦 (2021). 模拟增温和改变降雨频率对干旱半干旱区土壤呼吸的影响. 中国沙漠, 41, 100-108.] DOI
[15]	Hao LY, Zhang LH, Xie ZK, Zhao RF, Wang JF, Guo YF, Gao JP (2021). Influence of precipitation change on soil respiration in desert grassland. Environmental Science, 42, 4527-4537. DOI URL
	[蒿廉伊, 张丽华, 谢忠奎, 赵锐锋, 王军锋, 郭亚飞, 高江平 (2021). 降水变化对荒漠草原土壤呼吸的影响. 环境科学, 42, 4527-4537.]
[16]	Hou JF, Lü XT, Wang C, Wang P (2014). Variation of soil respiration and its underlying mechanism in grasslands of northern China. Chinese Journal of Applied Ecology, 25, 2840-2846.
	[侯建峰, 吕晓涛, 王超, 王朋 (2014). 中国北方草地土壤呼吸的空间变异及成因. 应用生态学报, 25, 2840-2846.]
[17]	IPCC Intergovernmental Panel on Climate Change (2021). Climate Change 2021: the Physical Science Basis. Cambridge University Press, Cambridge, UK.
[18]	Knapp AK, Beier C, Briske DD, Classen AT, Luo YQ, Reichstein M, Smith MD, Smith SD, Bell JE, Fay PA, Heisler JL, Leavitt SW, Sherry R, Smith B, Weng E (2008). Consequences of more extreme precipitation regimes for terrestrial ecosystems. BioScience, 58, 811-821. DOI URL
[19]	Knapp AK, Ciais P, Smith MD (2017). Reconciling inconsistencies in precipitation-productivity relationships: implications for climate change. New Phytologist, 214, 41-47. DOI PMID
[20]	Li XG, Han GX, Zhu LQ, Chen CN (2019). Effects of drying- wetting cycle caused by rainfall on soil respiration: progress and prospect. Chinese Journal of Ecology, 38, 567-575.
	[李新鸽, 韩广轩, 朱连奇, 陈超男 (2019). 降雨引起的干湿交替对土壤呼吸的影响: 进展与展望. 生态学杂志, 38, 567-575.]
[21]	Liu L, Wang X, Lajeunesse MJ, Miao G, Piao S, Wan S, Wu Y, Wang Z, Yang S, Li P, Deng M (2016). A cross-biome synthesis of soil respiration and its determinants under simulated precipitation changes. Global Change Biology, 22, 1394-1405. DOI PMID
[22]	Liu T, Wang L, Feng XJ, Zhang JB, Ma T, Wang X, Liu ZG (2018). Comparing soil carbon loss through respiration and leaching under extreme precipitation events in arid and semiarid grasslands. Biogeosciences, 15, 1627-1641. DOI URL
[23]	Liu T, Zhang YX, Xu ZZ, Zhou GS, Hou YH, Lin L (2012). Effects of short-term warming and increasing precipitation on soil respiration of desert steppe of Inner Mongolia. Chinese Journal of Plant Ecology, 36, 1043-1053. DOI
	[刘涛, 张永贤, 许振柱, 周广胜, 侯彦会, 林琳 (2012). 短期增温和增加降水对内蒙古荒漠草原土壤呼吸的影响. 植物生态学报, 36, 1043-1053.] DOI
[24]	Lopatin J, Araya-López R, Galleguillos M, Perez-Quezada JF (2022). Disturbance alters relationships between soil carbon pools and aboveground vegetation attributes in an anthropogenic peatland in Patagonia. Ecology and Evolution, 12, e8694. DOI: 10.1002/ECE3.8694. PMID
[25]	Lu RK (2000). Methods for Soil Agrochemical Analysis. China Agricultural Science and Technology Press, Beijing.
	[鲁如坤 (2000). 土壤农业化学分析方法. 中国农业科技出版社, 北京.]
[26]	Ma ZY, Liu HY, Mi ZR, Zhang ZH, Wang YH, Xu W, Jiang L, He JS (2017). Climate warming reduces the temporal stability of plant community biomass production. Nature Communications, 8, 15378. DOI: 10.1038/ncomms15378. PMID
[27]	Reichmann LG, Sala OE (2014). Differential sensitivities of grassland structural components to changes in precipitation mediate productivity response in a desert ecosystem. Functional Ecology, 28, 1292-1298. DOI URL
[28]	Ru JY, Zhou YQ, Hui DF, Zheng MM, Wan SQ (2018). Shifts of growing-season precipitation peaks decrease soil respiration in a semiarid grassland. Global Change Biology, 24, 1001-1011. DOI PMID
[29]	Schuur EAG (2003). Productivity and global climate revisited: the sensitivity of tropical forest growth to precipitation. Ecology, 84, 1165-1170. DOI URL
[30]	Song XH, Wang YH, Wang ZW, Kang H, Liu C, Li ZG, Qu ZQ, Han GD, Wang ZW (2019). Relationship between soil respiration and community underground biomass of desert steppe under different grazing intensities and water treatments. Acta Agrestia Sinica, 27, 962-968.
	[宋晓辉, 王悦骅, 王占文, 康慧, 刘晨, 李治国, 屈志强, 韩国栋, 王忠武 (2019). 不同放牧强度和水分处理下荒漠草原土壤呼吸与群落地下生物量的关系. 草地学报, 27, 962-968.] DOI
[31]	Su YF, Zhao CF, Wang Y, Ma ZS (2020). Spatiotemporal variations of precipitation in China using surface gauge observations from 1961 to 2016. Atmosphere, 11, 303. DOI: 10.3390/atmos11030303.
[32]	Wang CH, Zhang SN, Li KC, Zhang FM, Yang K (2021). Change characteristics of precipitation in northwest China from 1961 to 2018. Chinese Journal of Atmospheric Sciences, 45, 713-724.
	[王澄海, 张晟宁, 李课臣, 张飞民, 杨凯 (2021). 1961-2018年西北地区降水的变化特征. 大气科学, 45, 713-724.]
[33]	Wang CT, Long RJ, Wang GX, Liu W, Wang QL, Zhang L, Wu PF (2010). Relationship between plant communities, characters, soil physical and chemical properties, and soil microbiology in alpine meadows. Acta Prataculturae Sinica, 19, 25-34.
	[王长庭, 龙瑞军, 王根绪, 刘伟, 王启兰, 张莉, 吴鹏飞 (2010). 高寒草甸群落地表植被特征与土壤理化性状、土壤微生物之间的相关性研究. 草业学报, 19, 25-34.]
[34]	Wang JL, Teng DX, He XM, Li ZK, Chen YD, Ma W, Li WJ, Wang SY, Liu FY, Lü GH (2022). Spatial variation in the direct and indirect effects of plant diversity on soil respiration in an arid region. Ecological Indicators, 142, 109288. DOI: 10.1016/j.ecolind.2022.109288.
[35]	Wang Y, Xie Y, Rapson G, Ma H, Jing L, Zhang Y, Li J (2021). Increased precipitation enhances soil respiration in a semi-arid grassland on the Loess Plateau, China. PeerJ, 9, e10729. DOI: 10.7717/PEERJ.10729.
[36]	Wang ZW, Song XH, Wang YH, Wang ZW, Yan BL, Han GD (2020). Effects of simulated precipitation on soil respiration of Stipa breviflora desert steppe. Chinese Journal of Grassland, 42, 111-116.
	[王忠武, 宋晓辉, 王悦骅, 王占文, 闫宝龙, 韩国栋 (2020). 模拟降水对短花针茅荒漠草原土壤呼吸的影响. 中国草地学报, 42, 111-116.]
[37]	Xu M, Bian HF, Xu L, Chen Z, He NP (2020). Effects of precipitation pulse on soil carbon released by microbes in different grasslands. Acta Ecologica Sinica, 40, 1562-1571.
	[徐敏, 边红枫, 徐丽, 陈智, 何念鹏 (2020). 脉冲式降水对不同类型草地土壤微生物呼吸碳释放量的影响. 生态学报, 40, 1562-1571.]
[38]	Xu Z, Li MH, Zimmermann NE, Li SP, Li H, Ren H, Sun H, Han X, Jiang Y, Jiang L (2018). Plant functional diversity modulates global environmental change effects on grassland productivity. Journal of Ecology, 106, 1941-1951. DOI URL
[39]	Yang QX, Tian DS, Zeng H, Niu SL (2017). Main factors driving changes in soil respiration under altering precipitation regimes and the controlling processes. Chinese Journal of Plant Ecology, 41, 1239-1250. DOI URL
	[杨青霄, 田大栓, 曾辉, 牛书丽 (2017). 降水格局改变背景下土壤呼吸变化的主要影响因素及其调控过程. 植物生态学报, 41, 1239-1250.] DOI
[40]	Yao JQ, Yang Q, Liu ZH, Li CZ (2015). Spatio-temporal change of precipitation in arid region of the northwest China. Acta Ecologica Sinica, 35, 5846-5855.
	[姚俊强, 杨青, 刘志辉, 李诚志 (2015). 中国西北干旱区降水时空分布特征. 生态学报, 35, 5846-5855.]
[41]	Yu X, Wang X, Wu T, Wang QX, Ma Y, Xie L, Song NP (2021). Relationship between restoration of plant diversity and soil habitat in desert steppe. Acta Ecologica Sinica, 41, 8516-8524.
	[余轩, 王兴, 吴婷, 王启学, 马昀, 谢莉, 宋乃平 (2021). 荒漠草原植物多样性恢复与土壤生境的关系. 生态学报, 41, 8516-8524.]
[42]	Zhang HZ, Shi XZ, Yu DS, Wang HJ, Zhao YC, Sun WX, Huang BR (2009). Seasonal and regional variations of soil temperature in China. Acta Pedologica Sinica, 46, 227-234.
	[张慧智, 史学正, 于东升, 王洪杰, 赵永存, 孙维侠, 黄宝荣 (2009). 中国土壤温度的季节性变化及其区域分异研究. 土壤学报, 46, 227-234.]
[43]	Zhang JT (2004). Quantitative Ecology. Science Press, Beijing.
	[张金屯 (2004). 数量生态学. 科学出版社, 北京.]
[44]	Zhang Q, Li J, Singh VP, Xu CY (2013). Copula-based spatio- temporal patterns of precipitation extremes in China. International Journal of Climatology, 33, 1140-1152. DOI URL
[45]	Zhang R, Zhao X, Zuo X, Degen AA, Shang Z, Luo Y, Zhang Y, Chen J (2019). Effect of manipulated precipitation during the growing season on soil respiration in the desert- grasslands in Inner Mongolia, China. Catena, 176, 73-80. DOI
[46]	Zhang Y, Xie YZ, Ma HB, Zhang J, Jing L, Wang YT, Li JP (2021). The responses of soil respiration to changed precipitation and increased temperature in desert grassland in northern China. Journal of Arid Environments, 193, 104579. DOI: 10.1016/j.jaridenv.2021.104579.
[47]	Zhang YF, Wang XP, Hu R, Pan YX (2013). Effects of shrubs and precipitation on spatial-temporal variation of soil temperature at the microhabitats induced by desert shrubs. Journal of Desert Research, 33, 536-542.
	[张亚峰, 王新平, 虎瑞, 潘颜霞 (2013). 荒漠灌丛微生境土壤温度的时空变异特征——灌丛与降水的影响. 中国沙漠, 33, 536-542.] DOI
[48]	Zhao M, Guo SL, Wang R (2021). Diverse soil respiration responses to extreme precipitation patterns in arid and semiarid ecosystems. Applied Soil Ecology, 163, 103928. DOI: 10.1016/j.apsoil.2021.103928.
[49]	Zhu WW, Wang P, Fan J, Niu YB, Yu HL, Huang JY (2019). Effects of precipitation and N addition on soil C:N:P ecological stoichiometry and plant community composition in a desert steppe of Ningxia, northwestern China. Acta Prataculturae Sinica, 28(9), 33-44. DOI
	[朱湾湾, 王攀, 樊瑾, 牛玉斌, 余海龙, 黄菊莹 (2019). 降水量及N添加对宁夏荒漠草原土壤C:N:P生态化学计量特征和植被群落组成的影响. 草业学报, 28(9), 33-44.] DOI
[50]	Zuo XA, Zhang J, Lv P, Zhou X, Li YL, Luo YY, Luo YQ, Lian J, Yue XY (2016). Plant functional diversity mediates the effects of vegetation and soil properties on community- level plant nitrogen use in the restoration of semiarid sandy grassland. Ecological Indicators, 64, 272-280. DOI URL