Effects of simulated warming on biological soil crust-soil system respiration in alpine sandy lands
He-Ju ZHAO1,2, Yan-Peng YUE1,2, Xiao-Hong JIA,1,2,*, Long CHENG1,2, Bo WU1,2, Yuan-Shou LI3, Hong ZHOU1,2, Xue-Bin ZHAO41Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China 2Key Laboratory of Desert Ecosystem and Global Change, State Administration of Forestry and Grassland, Beijing 100091, China 3Chinese Academy of Meteorological Sciences, Beijing 100081, China 4 Qinghai Gonghe Desert Ecosystem National Positioning Research Station, Gonghe, Qinghai 813000, China
Supported by the National Key R&D Program of China(2016YFC0500801) the Special Survey on Science and Technology Basic Resources(2017FY100206) the National Natural Science Foundation of China(41471096) the National Natural Science Foundation of China(41371093)
Abstract Aims Biological soil crust is an important type of surface cover in alpine sandy lands. Understanding of the effect of warming on respiration from the biological soil crust-soil system in alpine regions can provide theoretical reference to the assessment of the response and feedback of biological soil crusts to climate changes. Methods The moss and algae crusts in the artificial vegetation restoration areas were taken as the research objects. The open top chamber (OTC) was used as a passive warming device to simulate warming. The daily and growing season dynamics of respiration rates in two types of biological soil crust-soil systems were measured. The effects of warming on CO2 emission and its temperature sensitivity were discussed. Important findings Both the daily and the growing season dynamics of respiration rate of the moss and algae crust-soil system showed “single-peak” curves and were not affected by warming. The daily peaks appeared around 13:00, and the growing season peaks appeared around August. Warming changed the daily peak value of respiration rate of the biological soil crust-soil system. In the relatively dry year (2017), moderate warming increased cumulative CO2 emission from the two types of biological soil crust-soil system during growing season, but the increase declined under excessive warming. In the relatively wet year (2018), as warming got greater, CO2 emission from the two types of biological soil crust-soil system increased more. The relationship between respiration rate and temperature of two types of biological soil crust-soil system followed the exponential function. In the relatively dry year, more increase of temperature induced smaller temperature sensitivity of CO2 emission, and the temperature sensitivity varied from 1.47 to 1.61 and 1.60 to 1.95 in the moss and algae crust soil system respectively. In the relatively wet year, with the increase of temperature, temperature sensitivity of system respiration increased, and the temperature sensitivity varied from 1.44 to 1.68 and 1.44 to 1.76 in the moss and algae crust soil system respectively. This study shows that global warming has greatly increased the respiration of biological soil crust-soil system in alpine ecosystems. Therefore, we should fully consider the impact of climate warming on the wide spread biological soil crusts in this area for better evaluation of carbon cycling processes in alpine ecosystems. Keywords:alpine sandy area;biological soil crust;warming;respiration;temperature sensitivity
PDF (1183KB)元数据多维度评价相关文章导出EndNote|Ris|Bibtex收藏本文 引用本文 赵河聚, 岳艳鹏, 贾晓红, 成龙, 吴波, 李元寿, 周虹, 赵雪彬. 模拟增温对高寒沙区生物土壤结皮-土壤系统呼吸的影响. 植物生态学报, 2020, 44(9): 916-925. DOI: 10.17521/cjpe.2020.0018 ZHAO He-Ju, YUE Yan-Peng, JIA Xiao-Hong, CHENG Long, WU Bo, LI Yuan-Shou, ZHOU Hong, ZHAO Xue-Bin. Effects of simulated warming on biological soil crust-soil system respiration in alpine sandy lands. Chinese Journal of Plant Ecology, 2020, 44(9): 916-925. DOI: 10.17521/cjpe.2020.0018
Fig. 1Changes of soil temperature (0-5 cm) under moss and algae crusts in open top chamber (OTC) a passive warming device with different specifications. A, Moss crust-soil system (TX). B, Algae crust-soil system (ZL). CK means control group; OTC1, OTC2, OTC3 represent different warming treatments.
Fig. 2Increase in soil temperature (0-5 cm) under moss and algae crusts in open top chamber (OTC) a passive warming device with different specifications. TX, moss crust-soil system; ZL, algae crust-soil system.
Fig. 3Daily dynamics of respiration rate of the biological soil crust-soil system under simulated warming. A, Moss crust-soil system (TX). B, Algae crust-soil system (ZL). CK means control group; OTC1, OTC2, OTC3 represent different warming treatments.
Fig. 4Growing season dynamics of respiration rate of the biological soil crust-soil system under simulated warming (mean ± SE). A, Moss crust-soil system (TX). B, Algae crust-soil system (ZL). CK means control group; OTC1, OTC2, OTC3 represent different warming treatments.
Table 3 表3 表3模拟增温下生物土壤结皮-土壤系统生长季累积CO2释放量 Table 3Cumulative CO2 emission from the biological soil crust-soil system in the growing season under simulated warming treatments
类型 Type
年份 Year
CO2释放量 CO2 emission (g·m-2)
CK (CV, %)
OTC1 (CV, %)
OTC2 (CV, %)
OTC3 (CV, %)
苔藓 Moss
2017
120.71 (31.62)
239.69 (27.64)
223.83 (30.83)
207.96 (34.96)
2018
386.97 (30.91)
430.63 (33.54)
442.82 (32.31)
481.35 (33.53)
藻类 Algae
2017
79.03 (51.98)
115.87 (53.15)
105.86 (56.54)
94.94 (56.39)
2018
236.80 (46.93)
272.71 (45.30)
285.90 (43.74)
308.64 (42.13)
CV is the coefficient of variation. CK means control group; OTC1, OTC2, OTC3 represent different warming treatments. CV为变异系数。CK为对照组, OTC1、OTC2、OTC3为不同增温处理。
Table 4 表4 表4模拟增温下生物土壤结皮-土壤系统呼吸速率与0-5 cm层土壤温度间的回归关系及温度敏感性(Q10)比较 Table 4Regression relationship between respiration rate of the biological soil crust-soil system and soil temperature in the 0-5 cm layer under simulated warming and comparison of temperature sensitivity (Q10) among different treatments
类型 Type
处理 Treatment
2017
2018
回归方程 Regression equation
R2
Q10
p
回归方程 Regression equation
R2
Q10
p
苔藓 Moss
CK
y = 0.389e0.0489x
0.36**
1.61
0.001
y = 1.131e0.0364x
0.37**
1.44
0.000
OTC1
y = 0.612e0.0422x
0.37**
1.53
0.008
y = 1.163e0.0419x
0.51**
1.52
0.001
OTC2
y = 0.546e0.0405x
0.53**
1.50
0.000
y = 0.901e0.047x
0.45**
1.60
0.000
OTC3
y = 0.502e0.0385x
0.66**
1.47
0.000
y = 1.009e0.0519x
0.58**
1.68
0.009
藻类 Algae
CK
y = 0.103e0.0667x
0.76**
1.95
0.001
y = 0.615e0.0363x
0.33**
1.44
0.000
OTC1
y = 0.090e0.064x
0.35**
1.90
0.005
y = 0.554e0.0445x
0.27**
1.56
0.004
OTC2
y = 0.149e0.0501x
0.66**
1.65
0.000
y = 0.361e0.0519x
0.40**
1.68
0.000
OTC3
y = 0.204e0.0467x
0.31**
1.60
0.000
y = 0.522e0.0567x
0.49**
1.76
0.000
* represents a significance level of 0.05; ** represents a significance level of 0.01. CK means control group; OTC1, OTC2, OTC3 represent different warming treatments. *代表达到0.05的显著性水平; **代表达到0.01的显著性水平。CK为对照组, OTC1、OTC2、OTC3为不同增温处理。
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Warming and drying suppress microbial activity and carbon cycling in boreal forest soils 1 2008
... 土壤呼吸主要包括自养呼吸(植物根系呼吸)和异养呼吸(土壤动物和微生物呼吸).本试验各处理OTC均远离植株2 m左右且在密闭遮光的土壤呼吸测量室8100-104中进行测定, 故可不考虑生物土壤结皮光合作用和植物根系呼吸对试验结果造成的影响.本研究发现, 增温增大了两种类型生物土壤结皮-土壤系统的CO2释放量, 增温幅度不同, 其增加程度也不同, 并且苔藓结皮-土壤系统的CO2释放量大于藻类结皮-土壤系统.这可能是以下原因所导致: 首先, 增温通过增加生物土壤结皮-土壤系统中的微生物量(Marilley et al., 1999), 直接影响微生物呼吸; 其次, 增温会增大生物土壤结皮-土壤系统中微生物的活性(Bokhorst et al., 2010), 从而促进土壤的呼吸作用; 最后, 增温能够激发生物土壤结皮-土壤系统中酶的活性, 加速呼吸底物中易分解和难分解组分的消耗, 对土壤呼吸产生影响(Yuste et al., 2010).过高的增温幅度, 将会对生物土壤结皮-土壤系统中的微生物活性和酶活性产生抑制, 同时还会降低土壤水分的有效性, 进而抑制土壤的呼吸作用; 但在水分条件较为充足时, 水分能够在一定程度上抵消过高幅度增温的消极影响, 对土壤呼吸表现出积极的作用(Zhao et al., 2019).相对于藻类结皮-土壤系统, 苔藓结皮-土壤系统土壤条件和微生物种类、数量和活性均处于更佳的状态, 且苔藓结皮自身的保水性能更高, 更利于激发其生理活性, 使苔藓结皮-土壤系统的CO2释放量大于藻类结皮-土壤系统(辜晨等, 2017).大量研究表明, 短期增温能够显著增加土壤的呼吸作用(Lin et al., 2001; Wan et al., 2007; Xia et al., 2009; 陈志芳, 2012; Maestre et al., 2013), 本研究结果与之一致.但在腾格里沙漠的研究却发现温度升高对各类型生物土壤结皮-土壤系统年平均CO2释放量无显著影响(徐冰鑫等, 2014), 这可能是由于不同研究区域土壤水分条件的不同所导致的.相对于高寒沙区, 腾格里沙漠的降水更为匮乏, 平均年降水量186.55 mm, 明显低于研究区2017年226.7 mm和2018年372.4 mm的降水量, 由于水分的限制, 生物土壤结皮-土壤系统中的微生物活性和呼吸底物的有效性也会受到限制, 且增温会进一步加剧土壤水分的缺失, 对土壤酶活性产生抑制(Allison & Treseder, 2008), 造成增温后CO2释放量的差别不大.也有研究表明, 增温后土壤呼吸没有发生明显变化的原因是土壤呼吸作用对温度产生适应性的结果(潘新丽等, 2008; 付微等, 2017), 这还需要进一步长期的观测去解释说明. ...
Temperature dependence of soil CO2 efflux is strongly modulated by seasonal patterns of moisture availability in a Mediterranean ecosystem 1 2009
... 土壤呼吸的温度敏感性能够反映气候变暖与全球生态系统碳循环间的关系, 温度的升高能够对土壤呼吸的温度敏感性产生影响(Davidson & Janssens, 2006; Liu et al., 2008; Zhao et al., 2019).有研究表明, 土壤呼吸的温度敏感性会随温度的升高而降低(Xu & Qi, 2001; Luo et al., 2010; 杨庆朋等, 2011), 但本研究发现, 相对湿润年份(2018), 降水的增多, 增温增大了两种类型生物土壤结皮-土壤系统呼吸生长季尺度的温度敏感性, 且增温幅度越高, 增加程度越大.这可能是由于水分条件的差异抵消了过高幅度增温的效果, 反而有利于微生物的生理活动, 增加了土壤呼吸的温度敏感性(Zhao et al., 2019).水分会通过影响土壤中基质的扩散对土壤呼吸产生影响, 土壤中有机质与酶的运输都需要在液相中进行, 增温会降低土壤的水分含量, 降低呼吸底物和酶的扩散转移与微生物的活性, 从而降低微生物与呼吸底物的接触机会, 影响土壤呼吸的敏感性; 而当水分较为充足时, 适度增温, 将会激发微生物的活性与酶活性, 加速呼吸底物分解, 提高土壤呼吸的温度敏感性(杨毅等, 2011).多数研究表明, 土壤呼吸的Q10值对土壤水分具有一定的依赖性, 通常情况下, 土壤水分缺失会导致Q10下降, 而一定程度上土壤含水量的升高, Q10也会相应增加(Janssens & Pilegaard, 2003; Reichstein et al., 2005; Almagro et al., 2009).在亚热带草原生态系统的研究表明, 土壤水分的增多, 能够显著提高土壤呼吸的Q10值(McCulley et al., 2007), 本研究结果与之相同.由于本研究只是对短期增温对于两种类型生物土壤结皮-土壤系统呼吸温度敏感性影响的初步探讨, 有关增温对土壤呼吸温度敏感性影响的内在机制与长期效应, 还需我们进一步长期观测研究. ...
Impacts of extreme winter warming events on litter decomposition in a sub-Arctic heathland 1 2010
... 土壤呼吸主要包括自养呼吸(植物根系呼吸)和异养呼吸(土壤动物和微生物呼吸).本试验各处理OTC均远离植株2 m左右且在密闭遮光的土壤呼吸测量室8100-104中进行测定, 故可不考虑生物土壤结皮光合作用和植物根系呼吸对试验结果造成的影响.本研究发现, 增温增大了两种类型生物土壤结皮-土壤系统的CO2释放量, 增温幅度不同, 其增加程度也不同, 并且苔藓结皮-土壤系统的CO2释放量大于藻类结皮-土壤系统.这可能是以下原因所导致: 首先, 增温通过增加生物土壤结皮-土壤系统中的微生物量(Marilley et al., 1999), 直接影响微生物呼吸; 其次, 增温会增大生物土壤结皮-土壤系统中微生物的活性(Bokhorst et al., 2010), 从而促进土壤的呼吸作用; 最后, 增温能够激发生物土壤结皮-土壤系统中酶的活性, 加速呼吸底物中易分解和难分解组分的消耗, 对土壤呼吸产生影响(Yuste et al., 2010).过高的增温幅度, 将会对生物土壤结皮-土壤系统中的微生物活性和酶活性产生抑制, 同时还会降低土壤水分的有效性, 进而抑制土壤的呼吸作用; 但在水分条件较为充足时, 水分能够在一定程度上抵消过高幅度增温的消极影响, 对土壤呼吸表现出积极的作用(Zhao et al., 2019).相对于藻类结皮-土壤系统, 苔藓结皮-土壤系统土壤条件和微生物种类、数量和活性均处于更佳的状态, 且苔藓结皮自身的保水性能更高, 更利于激发其生理活性, 使苔藓结皮-土壤系统的CO2释放量大于藻类结皮-土壤系统(辜晨等, 2017).大量研究表明, 短期增温能够显著增加土壤的呼吸作用(Lin et al., 2001; Wan et al., 2007; Xia et al., 2009; 陈志芳, 2012; Maestre et al., 2013), 本研究结果与之一致.但在腾格里沙漠的研究却发现温度升高对各类型生物土壤结皮-土壤系统年平均CO2释放量无显著影响(徐冰鑫等, 2014), 这可能是由于不同研究区域土壤水分条件的不同所导致的.相对于高寒沙区, 腾格里沙漠的降水更为匮乏, 平均年降水量186.55 mm, 明显低于研究区2017年226.7 mm和2018年372.4 mm的降水量, 由于水分的限制, 生物土壤结皮-土壤系统中的微生物活性和呼吸底物的有效性也会受到限制, 且增温会进一步加剧土壤水分的缺失, 对土壤酶活性产生抑制(Allison & Treseder, 2008), 造成增温后CO2释放量的差别不大.也有研究表明, 增温后土壤呼吸没有发生明显变化的原因是土壤呼吸作用对温度产生适应性的结果(潘新丽等, 2008; 付微等, 2017), 这还需要进一步长期的观测去解释说明. ...
The impacts of climate change and human activities on biogeochemical cycles on the Qinghai-Tibetan Plateau 1 2013
Changes in biocrust cover drive carbon cycle responses to climate change in drylands 1 2013
... 生物土壤结皮是由蓝藻、地衣、藓类等隐花植物和土壤微生物通过菌丝体、假根和分泌物等胶结土壤表层细小颗粒形成的复合体(Eldridge & Greene, 1994; Lan et al., 2012).它是干旱半干旱地区重要的地表覆盖类型, 在荒漠生态系统中的覆盖度能达到40%以上(李新荣等, 2009), 在防风固沙、保持水土、生态恢复等方面具有重要的生态意义.生物土壤结皮独特的组成与结构使其具有特殊的生理性能, 既能进行光合作用, 也能进行呼吸作用, 进而对土壤呼吸以及生态系统碳循环产生重要影响. ...
Influence of an elevated atmospheric CO2 content on soil and rhizosphere bacterial communities beneathLolium perenne and Trifolium repens under field conditions 1 1999