Seasonal variations in soil respiration, heterotrophic respiration and autotrophic respiration of a wheat and maize rotation cropland in the North China Plain

• Published in: Agricultural and forest meteorology 2013-10, Vol.180, p.34-43
• Main Authors: Zhang, Quan, Lei, Hui-Min, Yang, Da-Wen
• Format: Article
• Language: English
• Subjects: Agricultural and forest climatology and meteorology. Irrigation. Drainage; agricultural land; Agronomy. Soil science and plant productions; air temperature; Autotrophic respiration; Biochemistry and biology; Biological and medical sciences; Chemical, physicochemical, biochemical and biological properties; China; Climate; corn; Cropping systems. Cultivation. Soil tillage; field capacity; flooded conditions; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Generalities. Cropping systems and patterns; growing season; Heterotrophic respiration; Maize; Moisture content; North China Plain; Physics, chemistry, biochemistry and biology of agricultural and forest soils; Respiration; Seasons; Soil (material); Soil respiration; Soil science; soil temperature; soil water content; Triticum aestivum; Wheat; wilting point; Zea mays
• ISSN: 0168-1923; 1873-2240
• DOI: 10.1016/j.agrformet.2013.04.028

•We reported three years’ observations of soil respiration over the North China Plain.•Autotrophic respiration contributed 36% and 29% to total soil respiration in wheat and maize, respectively.•Seasonal variations in soil respiration and its components were explored, seasonal average values were estimated.•Soil temperature and water content were main controlling factors of heterotrophic respiration.•Soil temperature and GPP were main controlling factors of autotrophic respiration. Determining soil respiration from croplands is necessary for evaluating the global terrestrial carbon budget and how it is altered in future climates. This study explored seasonal characteristics and controlling factors of soil respiration in a typical cropland area in the North China Plain. Total soil respiration (RS) was partitioned into heterotrophic (RH) and autotrophic (RA) components using the root exclusion method. The experiments showed that the seasonal average RS values were 5.25μmolm−2s−1 for the wheat growing season and 6.00μmolm−2s−1 for the maize growing season. Seasonal average RH and RA values were 3.34μmolm−2s−1 and 1.91μmolm−2s−1, respectively, for wheat, and were 4.25μmolm−2s−1 and 1.75μmolm−2s−1, respectively, for maize. The seasonal average ratio of RA to RS (RA/RS) was 36% for wheat and 29% for maize. Over a whole year, RH was the dominant component of RS in both the wheat and maize growing seasons. RH increased exponentially with the average soil temperature collected in the upper 10cm (TS0–10), with a Q10 value of 1.65. Soil water content (θ) had no discernible influence on RH when θ was between wilting point (θwp) and field capacity (θfc). A value of θ larger than θfc suppressed RH, which can be characterized by a quadratic curve. RA increased exponentially with TS0–10 in both of the wheat and maize growing seasons, and the corresponding Q10 values were 2.69 and 2.85, respectively. However, the temperature dependence of RA in the two crop seasons cannot be explained by a single temperature response curve. Moreover, the RA values for the wheat and maize growing seasons were more sensitive to temperature changes than RH at the study site. Soil water content had no discernible influence on RA in the wheat growing season but suppressed RA when water logging occurred in the maize growing season. However, RA recovered afterwards even when the soil water content was high. Comparisons between wheat respiration values collected at different sites showed that the