一种适用于套作系统温室气体收集装置的设计及其效果验证

Design and Effect Verification of Greenhouse Gas Collection Device in the Relay Strip Intercropping System

摘要: 为了实现农艺和农机相结合，提高对农业温室气体排放研究的科学性，本文设计了一种在套作模式下，能根据共生作物高度调节容量和取气口位置的农田作物温室气体收集装置。并以不同大豆种植模式对该装置进行效果验证。结果表明：在单作、玉米–大豆套作、休闲处理下，N₂O平均排放通量分别为2.42 ± 2.23 mg/(m²∙h)、1.97 ± 1.82 mg/(m²∙h)、1.21 ± 0.95 mg/(m²∙h)，存在显著差异(P < 0.05)，且气体排放量呈现套作明显低于单作模式；单作、玉米–大豆套作、休闲处理下的CH₄平均排放通量是负值，分别为−0.17 mg/(m²∙h)、−5.75 mg/(m²∙h)、−4.34 mg/(m²∙h)，土壤成为CH₄吸收“汇”；CO₂排放量表现为套作下排放量10,085.67 mg/(m²∙h)低于单作模式下的排放量13,263.93 mg/(m²∙h)，说明玉豆套作可以减少温室气体排放，但是测得休闲模式下CO₂的平均通量为1852.90 mg/(m²∙h)，远远高于下辽河平原偏东的CO₂排放通量108.7 mg/(m²∙h)，这是因为CO₂的释放具有很大的时空变异性。最后，通过对每种模式的重复试验，与以往的实验结果对比，具有相对一致性，说明本装置有效且具有广阔的推广应用前景。

Abstract: In order to realize the combination of agronomy and agricultural machinery and improve the scien-tific research on agricultural greenhouse gas emissions, this paper designs a farmland crop green-house gas collection device which can be adjusted according to the height of the symbiotic crop and the position of gas hole. The effect of the device was verified by different soybean plant patterns. The results showed that there was a significant difference(P < 0.05) in the N₂O emis-sions from different treatments, the N₂O emissions averaged 2.42 ± 2.23 mg/(m²∙h) for the monoculture mode, 1.97 ± 1.82 mg/(m²∙h) for the maize-soybean mode, 1.21 ± 0.95 mg/(m²∙h) for the leisure mode. Meanwhile the emissions in relay strip intercropping were significantly lower than that in monoculture mode;the CH₄ emissions averaged −0.17 mg/(m²∙h) for the monoculture mode, −5.75 mg/(m²∙h) for the maize-soybean mode, −4.34 mg/(m²∙h) for the leisure mode. CH₄ emissions are negative values which means that the soil is a sink for CH₄; the CO₂ emissions averaged 10,085.67 mg/(m²∙h) for the maize-soybean mode which was lower than the missions of 13,263.93 mg/(m²∙h) for the monoculture mode, it reveals that the maize-soybean mode has a potential for reducing GHG emissions. However, CO₂ emissions averaged 1852.90 mg/(m²∙h) for the leisure mode in this paper were much higher than in Lower Reaches of Liaohe Plain, because the release of CO₂ has a lot of time and space variability. The results of the experimental study are consistent with the previous experimental results by repeating the test for each pattern, indicating that the device is effective and has a broad application foreground.