Ni Xue, Jiang Chang-Sheng, Chen Shi-Jie, Li Xiao-Xi, Shi Xiao-Jun, Hao Qing-Ju
Key Laboratory of Eco-environments in Three Gorges Reservoir Region of Ministry of Education, College of Resources and Environment, Southwest University, Chongqing 400716, China.
National Purple Soil Fertility and Fertilizer Efficiency Monitoring Base, Chongqing 400716, China.
Huan Jing Ke Xue. 2019 May 8;40(5):2404-2412. doi: 10.13227/j.hjkx.201809045.
To investigate the effects of plastic film mulching and nitrogen fertilizer application on CH emissions from a vegetable field, static opaque and gas chromatography methods were applied, and field observations of a chili-radish rotation system, from May 2014 to April 2016, were carried out in the Key Field Station for Monitoring of Eco-Environment of Purple Soil of the Ministry of Agriculture of China in the farm of Southwest University in Chongqing. Eight treatments were set up in the field experiment:control routine (no N application and no plastic film mulching) (NN0), control mulching (FN0), low N routine (NN1), low N mulching (FN1), conventional N routine (NN2), conventional N mulching (FN2), high N routine (NN3), and high N mulching (FN3). The characteristics and influencing factors of CH emissions and the changes of soil carbon and nitrogen composition from all treatments were studied. The results showed that there was no significant difference in the CH emissions from the vegetable fields between the mulching methods. From May 2014 to April 2016, the annual average cumulative absorption of CH in nitrogen-free, low-nitrogen, medium-nitrogen, and high-nitrogen vegetable fields under film-mulching cultivation was 28.96, 51.90, 43.43, and 34.41 mg·m, respectively. The average annual cumulative uptake of CH under conventional planting was 40.76, 63.56, 62.77, and 21.92 mg·m, respectively. Different nitrogen application gradients had no significant effect on CH emissions from vegetable fields. There was a significant positive correlation between CH uptake and soil temperature, and a significant negative correlation between CH and soil water content. Plastic film coverage accelerated the mineralization of soil carbon in the pepper season, but there was no significant effect in the radish season.
为研究地膜覆盖和氮肥施用对菜地CH排放的影响，采用静态暗箱-气相色谱法，于2014年5月至2016年4月，在中国农业农村部紫色土生态环境监测重点野外科学观测试验站（位于重庆西南大学农场），对辣椒-萝卜轮作系统进行了田间观测。田间试验设置了8个处理：常规对照（不施氮、不覆盖地膜）（NN0）、覆盖对照（FN0）、低氮常规（NN1）、低氮覆盖（FN1）、常规氮常规（NN2）、常规氮覆盖（FN2）、高氮常规（NN3）和高氮覆盖（FN3）。研究了各处理CH排放特征、影响因素以及土壤碳氮组成变化。结果表明，不同覆盖方式下菜地CH排放差异不显著。2014年5月至2016年4月，覆膜栽培下无氮、低氮、中氮和高氮菜地CH年均累积吸收量分别为28.96、51.90、43.43和34.41 mg·m ，常规种植下CH年均累积吸收量分别为40.76、63.56、62.77和21.92 mg·m 。不同施氮梯度对菜地CH排放影响不显著。CH吸收与土壤温度呈显著正相关，与土壤含水量呈显著负相关。地膜覆盖在辣椒季加速了土壤碳矿化，但在萝卜季无显著影响。
