|
1
|
Li M, Liu T, Duan L, Ma L, Wang Y, Zhou Y, Li Y, Zhao X, Wang X, Wang G, Lei H. Hydrologic gradient changes of soil respiration in typical steppes of Eurasia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 794:148684. [PMID: 34214805 DOI: 10.1016/j.scitotenv.2021.148684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 06/20/2021] [Accepted: 06/22/2021] [Indexed: 06/13/2023]
Abstract
Soil respiration (RS) is affected by many factors and shows significant diurnal and seasonal changes at different spatial and temporal scales. However, in a semi-arid steppe, the mechanism of the dynamic influence of environmental factors on RS is not clear, and the effect of subtle changes of soil water on RS under drought stress is yet to be explored. Therefore, Xilin River Basin, was the study area and a hydrological gradient on the four ecosystems for RS and hydrometeorological monitoring was selected. We proposed the use of dynamic sunrise and sunset time to distinguish day from night and determine related statistics. Additionally, we analyzed the temporal variation of RS and its response process and mechanism for hydrometeorological factors during the growing season and at daily scales. Further, we quantitatively simulated the RS of 594 scenarios in different growing season stages, ecosystems, and precipitation patterns. Results showed that: (1) in the hydrological gradient belt, different ecosystems exhibited the same trend but different characteristics of RS regulation. From May to November 2020, RS was 2.34-3.89, 1.89-5.97, 1.90-5.27 and 2.29-3.45 gC m-2 day-1 for the four ecosystems. (2) The use of dynamic sunrise and sunset time to distinguish day and night can more accurately describe the statistical value of each variable, which exhibits remarkable feasibility in daily scale research. (3) The changes in RS were adequately explained by temperature at various time scales, and the photosynthetically active radiation was positively correlated with RS at the daily scale. The special soil water content (MS) condition in the study area was not sufficient to explain RS. (4) Precipitation can affect RS by changing soil and air; however, only when precipitation exceeds the effective precipitation threshold of 0.6 ± 0.3 mm, it significantly affects RS.
Collapse
Affiliation(s)
- Mingyang Li
- Inner Mongolia Water Resource Protection and Utilization Key Laboratory, Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Tingxi Liu
- Inner Mongolia Water Resource Protection and Utilization Key Laboratory, Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot 010018, China.
| | - Limin Duan
- Inner Mongolia Water Resource Protection and Utilization Key Laboratory, Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Long Ma
- Inner Mongolia Water Resource Protection and Utilization Key Laboratory, Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Yixuan Wang
- Inner Mongolia Water Resource Protection and Utilization Key Laboratory, Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Yajun Zhou
- Inner Mongolia Water Resource Protection and Utilization Key Laboratory, Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Yuankang Li
- Inner Mongolia Water Resource Protection and Utilization Key Laboratory, Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Xinyu Zhao
- Inner Mongolia Water Resource Protection and Utilization Key Laboratory, Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Xueqin Wang
- Inner Mongolia Water Resource Protection and Utilization Key Laboratory, Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Guoqiang Wang
- College of Water Sciences, Beijing Normal University, Beijing 100875, China
| | - Huimin Lei
- State Key Laboratory of Fydroscience and Engineering, Department of Hydraulic Engineering Tsinghua University, Beijing 100084, China
| |
Collapse
|