Maize ( Zea mays L.), a staple crop in the North China Plain, contributing substantially to agricultural nitrous oxide (N 2 O) emissions in this region. Many studies have focused on various agricultural management mea...Maize ( Zea mays L.), a staple crop in the North China Plain, contributing substantially to agricultural nitrous oxide (N 2 O) emissions in this region. Many studies have focused on various agricultural management measures to reduce N 2 O emissions. However, few have investigated soil N 2 O emissions in intercropping systems. In the current study, we investigate whether maize-soybean intercropping treatments could reduce N 2 O emission rates. Two differently configured maize-soybean intercropping treatments, 2:2 intercropping (two rows of maize and two rows of soybean, 2M2S) and 2:1 intercropping (two rows of maize and one row of soybean, 2M1S), and monocultured maize (M) and soybean (S) treatments were performed using a static chamber method. The results showed no distinct yield advantage for the intercropping systems. The total N 2 O production from the various treatments was 0.15 ± 0.04–113.85 ± 12.75 µg m −2 min −1 . The cumulative N 2 O emission from the M treatment was 16.9 ± 2.3 kg ha −1 over the entire growing season (three and a half months), which was significantly higher ( P < 0.05) than that of the 2M2S and 2M1S treatments by 36.6% and 32.2%, respectively. Two applications of nitrogen (N) fertilizer (as urea) at 240 kg N ha −1 each induced considerable soil N 2 O fluxes. Short-term N 2 O emissions (within one week after each of the two N applications) accounted for 74.4%–83.3% of the total emissions. Soil moisture, temperature, and inorganic N were significantly correlated with soil N 2 O emissions ( R 2 = 0.246–0.365, n = 192, P < 0.001). Soil nitrate (NO − )3 and moisture decreased in the intercropping treatments during the growing season. These results indicate that maize-soybean intercropping can reduce soil N 2 O emissions relative to monocultured maize.展开更多
基金supported by the National Key Technology R&D Program of China(Nos.2011BAD-16B15 and 2012BAD14B03)the Fundamental Research Funds for Rubber Research Institute,Chinese Academy of Tropical Agricultural Sciences(No.1630022014019)
文摘Maize ( Zea mays L.), a staple crop in the North China Plain, contributing substantially to agricultural nitrous oxide (N 2 O) emissions in this region. Many studies have focused on various agricultural management measures to reduce N 2 O emissions. However, few have investigated soil N 2 O emissions in intercropping systems. In the current study, we investigate whether maize-soybean intercropping treatments could reduce N 2 O emission rates. Two differently configured maize-soybean intercropping treatments, 2:2 intercropping (two rows of maize and two rows of soybean, 2M2S) and 2:1 intercropping (two rows of maize and one row of soybean, 2M1S), and monocultured maize (M) and soybean (S) treatments were performed using a static chamber method. The results showed no distinct yield advantage for the intercropping systems. The total N 2 O production from the various treatments was 0.15 ± 0.04–113.85 ± 12.75 µg m −2 min −1 . The cumulative N 2 O emission from the M treatment was 16.9 ± 2.3 kg ha −1 over the entire growing season (three and a half months), which was significantly higher ( P < 0.05) than that of the 2M2S and 2M1S treatments by 36.6% and 32.2%, respectively. Two applications of nitrogen (N) fertilizer (as urea) at 240 kg N ha −1 each induced considerable soil N 2 O fluxes. Short-term N 2 O emissions (within one week after each of the two N applications) accounted for 74.4%–83.3% of the total emissions. Soil moisture, temperature, and inorganic N were significantly correlated with soil N 2 O emissions ( R 2 = 0.246–0.365, n = 192, P < 0.001). Soil nitrate (NO − )3 and moisture decreased in the intercropping treatments during the growing season. These results indicate that maize-soybean intercropping can reduce soil N 2 O emissions relative to monocultured maize.
