Journal cover Journal topic
Hydrology and Earth System Sciences An interactive open-access journal of the European Geosciences Union
Hydrol. Earth Syst. Sci., 22, 3075-3086, 2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
Research article
30 May 2018
Precipitation alters plastic film mulching impacts on soil respiration in an arid area of northwest China
Guanghui Ming1, Hongchang Hu1, Fuqiang Tian1, Zhenyang Peng1, Pengju Yang1, and Yiqi Luo2,3 1Department of Hydraulic Engineering, State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China
2Department of Earth System Science, Tsinghua University, Beijing 100084, China
3College of Engineering, Forestry, and Natural Sciences, Northern Arizona University, Flagstaff, Arizona, USA
Abstract. Plastic film mulching (PFM) has widely been used around the world to save water and improve crop yield. However, the effect of PFM on soil respiration (Rs) remains unclear and could be further confounded by irrigation and precipitation. To address these topics, controlled experiments were conducted in mulched and non-mulched fields under drip irrigation from 2014 to 2016 in an arid area of the Xinjiang Uygur Autonomous Region, northwest China. The spatio-temporal pattern of soil surface CO2 flux as an index of soil respiration under drip irrigation with PFM was investigated, and the confounded effects of PFM and irrigation/precipitation on soil respiration were explored. The main findings were as follows. (1) Furrows, planting holes, and plastic mulch are three important pathways of soil CO2 emissions in mulched fields, of which the planting hole efflux outweighs that from the furrow, with the largest values of 8.0 and 6.6 µmol m−2 s−1, respectively, and the plastic mulch itself can emit up to 3.6 µmol m−2 s−1 of CO2. (2) The frequent application of water (i.e. through irrigation and precipitation) elevates soil moisture and soil respiration and enhances their variation. The resultant higher variation of soil moisture further alleviates the sensitivity of soil respiration to soil temperature, leading to a weak correlation and lower Q10 values. (3) Soil CO2 effluxes from furrows and ridges in mulched fields outweigh the corresponding values in non-mulched fields in arid areas. However, this outweighing relation attenuates with increasing precipitation. Furthermore, by combining our results with those from the literature, we show that the difference in soil CO2 effluxes between non-mulched and mulched fields presents a linear relation with the amount of precipitation, which results in negative values in arid areas and positive values in humid areas. Therefore, whether PFM increases soil respiration or not depends on the amount of precipitation during the crop-growing season.
Citation: Ming, G., Hu, H., Tian, F., Peng, Z., Yang, P., and Luo, Y.: Precipitation alters plastic film mulching impacts on soil respiration in an arid area of northwest China, Hydrol. Earth Syst. Sci., 22, 3075-3086,, 2018.
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Short summary
The purpose of this research was to detect the effect of plastic film mulching (PFM), a widely applied cultivation method, on soil respiration. We found that soil respiration was not only affected by PFM, but it was also affected by irrigation and precipitation, and whether the PFM increases soil respiration compared to a non-mulched field largely depends on precipitation in the field. The result has an important meaning for agricultural carbon sequestration in the context of global warming.
The purpose of this research was to detect the effect of plastic film mulching (PFM), a widely...