Respiration rate of moss-dominated biocrusts and their relationships with temperature and moisture in a semiarid ecosystem
Respiration rate of moss-dominated biocrusts and their relationships with temperature and moisture in a semiarid ecosystem
复制标题
半干旱生态系统中以苔藓为主的生物结皮的呼吸速率及其与温度和水分的关系
DOI：
10.1016/j.catena.2019.104195
复制
发表时间：
2019-12
期刊：
影响因子：
6.2
通讯作者：
Hu Kelin
中科院分区：
文献类型：
--
作者：
Yao Xiaomeng;Xiao Bo;Kidron Giora J;Hu Kelin
生物结壳广泛分布于世界各地的旱地生态系统中，但其呼吸速率(Rs)及其对土壤温度和湿度的响应尚未得到充分的研究。在中国黄土高原半干旱区，利用全自动土壤呼吸系统连续测定了夏季苔藓类生物结壳的Rs值(104 d)，并对其与2、5、10 cm深度土壤温湿度的关系进行了深入分析。结果表明，与底层土壤相比，生物结皮在白天高出115%(t= −3.82P<； 0.001)Rs，在夜间高出44%(t= −10.22P<； 0.001)Rs，昼夜平均增加81%(2.52vs.1.39molMol μ m−2s−1)。湿态(土壤湿度 μ ≥ 0.15 cm~3−3)和干燥状态(土壤湿度 = 0.05 cm~3−3)的Rs值分别为0.27~2.83− μ m−2s−1和2.11 μm m−2s−1，日平均值为2.11 μ −m μ m−2s−1。 0.001)，Q10值在1.73%到2.08%之间。生物结壳的Rs值与土壤水分呈正相关，但不能很好地用二次函数(R2≤ 0.22)来拟合。基于2 cm土壤水分和温度的模型比基于5或10 cm土壤温度和平均气温的模型表现得更好(R2= 0.53；P<； 0.001)。总之，苔藓生物壳对半干旱生态系统土壤呼吸有重要贡献，首先(直接和直接)由于生物渣土层中丰富多样的微生物群落，其次(和间接)由于生物渣土对土壤温度和水分状况的影响。在模拟生物结壳表面的Rs值时，应优先使用2 cm深度(生物灰层)的温度和水分，而不是使用通常使用的土壤深度(5 cm)来估算无生物结壳的普通土壤的Rs值。
Biocrusts are widely distributed throughout the world in dryland ecosystems, but their respiration rate (Rs) and responses to soil temperature and mositure have not yet been fully investigated. In a semiarid region of the Loess Plateau in China, theRsof moss-dominated biocrusts was continuously (104 days) measured in summer through an automated soil respiration system, and their relationships with soil temperature and moisture at 2, 5, and 10 cm depths were intensively analyzed. The results showed the biocrusts had 115% higher (t= −3.82,P< 0.001)Rsduring day and 44% higher (t= −10.22,P< 0.001)Rsduring night as compared with the underlying soil; they averagely increasedRsby 81% (2.52 vs. 1.39 μmol m−2s−1) across day and night. More specifically, theRsof biocrusts ranged from 0.33 to 6.33 μmol m−2s−1in wet conditions (soil moisture ≥ 0.15 cm3cm−3) and 0.27 to 2.83 μmol m−2s−1in dry conditions (soil moisture = 0.05 cm3cm−3), with a daily mean of 2.11 μmol m−2s−1. Particularly, in wet conditions theRsof biocrusts had positive responses to increasing temperature, and their relationship was well fitted with an exponential function (R2≥ 0.44;P< 0.001), with aQ10value ranging between 1.73 and 2.08. Similarly, theRsof biocrusts was positively correlated with soil moisture, but their relationship was not well fitted with the quadratic function (R2≤ 0.22). A model based on the soil moisture and temperature at 2 cm depth performed much better (R2= 0.53;P< 0.001) withRsthan that based on the soil moisture and temperature at 5 or 10 cm depth or even air temperature. In conclusion, moss biocrusts made a significant contribution to soil respiration in semiarid ecosystem, firstly (and directly) due to the rich and diversified microbial communities in biocrust layer and secondly (and indirectly) due to the biocrust effects on soil temperature and moisture regimes. The temperature and moisture at 2 cm depth (biocrust layer) should be employed with a higher priority in simulatingRsof biocrusted surfaces, rather than the commonly used soil depth (5 cm) in estimatingRsof the ordinary soil without biocrusts.
登录
查看更多内容
影响因子：
4.8
作者：
A. Thomas;S. Hoon;P. Linton
通讯作者：
A. Thomas;S. Hoon;P. Linton
影响因子：
3.7
作者：
Feng W;Zhang Y;Jia X;Wu B;Zha T;Qin S;Wang B;Shao C;Liu J;Fa K
通讯作者：
Fa K
影响因子：
3.7
作者：
Castillo-Monroy, Andrea P.;Maestre, Fernando T.;Garcia-Palacios, Pablo
通讯作者：
Garcia-Palacios, Pablo
DOI：
--
发表时间：
1998
期刊：
--
影响因子：
--
作者：
Ben Wang;T. Zha;Xin Jia;Bin Wu;Yuqing Zhang;Shu-gao Qin
通讯作者：
Ben Wang;T. Zha;Xin Jia;Bin Wu;Yuqing Zhang;Shu-gao Qin
影响因子：
9.7
作者：
E. Zaady;U. Kuhn;B. Wilske;L. Sandoval-Soto;J. Kesselmeier
通讯作者：
E. Zaady;U. Kuhn;B. Wilske;L. Sandoval-Soto;J. Kesselmeier