化学氮肥不同途径氮素损失的原位观测与区域估算

发布时间：2018-04-23 18:22

  本文选题：N_2O排放 + NH_3挥发　； 参考：《南京农业大学》2015年硕士论文

【摘要】：为了解农田常规施肥条件下的不同途径氮素损失特征,本文通过田间原位试验同步研究了长江中下游地区夏玉米和旱直播水稻生长季氮肥施用后的农田N_2O排放,NH3挥发,氮渗漏和地表径流的变化。结果表明,在玉米生长季(复合肥为基肥,尿素为追肥,基追肥水平均为150kgN·ha-1),整个生长季N_2O排放系数为3.3%,NH3挥发损失率为10.2%,氮渗漏和地表径流损失率分别为11.2%和5.1%。基肥施用以氮素渗漏损失为主,而追肥氮素损失以氨挥发和渗漏为主,表明不同途径化肥氮素损失主要受氮肥品种影响。同理在复合肥为基肥,尿素为追肥,基肥为162 kgN·ha-1,追肥为108kgN.ha-1的条件下,整个水稻生长季N_2O排放系数为1.5%,NH3挥发损失率为9.7%,硝态氮渗漏损失率为4.9%。因旱直播水稻生长季无排水,地表径流氮损失率为零。本文按照土壤类型和气候因素将全国划分为8个区域,通过收集目前已发表的有关中国三大作物水稻、小麦和玉米2000-2012年之间的N_2O排放、NH3挥发、氮渗漏和径流量的数据,以及通过查询中国气象数据库相关的气象数据,建立温度和降水数据修正后的四种途径氮损失量与施氮量之间的模型。根据收集到的每个区域三种作物的年平均施氮量以及耕作面积,估算中国2000年以来每年水稻、小麦和玉米的平均N_2O 排放量分别为 41.73±13.67Gg,44.52±11.51Gg,72.33±11.65Gg;NH3挥发量分别为 1035.33±264.54Gg,331.28±81.13Gg,951.71±144.03Gg;总氮径流量分别为263.75±60.14Gg,329.98±64.43Gg,89.23±32.03Gg;和总氮渗漏量分别为196.78±85.46Gg,213.77±76.63Gg,938.62±91.24Gg。2000 年以来水稻、小麦和玉米N_2O排放导致的年均经济损失分别为17.25±5.65,20.718.40±4.76,29.96±4.82亿元;NH3挥发分别为 27.54±7.04,8.81±2.16,25.31±3.83 亿元;总氮径流分别为 26.75±6.10,33.47±6.54,9.05±3.25 亿元;总氮渗漏分别为 19.96±8.67,21.68±7.77,95.22±9.25 亿元。
[Abstract]:In order to understand the characteristics of nitrogen loss in different ways under conventional fertilization conditions, in this paper, the NH _ 3 volatilization of N _ 2O emission from summer maize and dry direct seeding rice growing season in the middle and lower reaches of Yangtze River was studied by in-situ field experiment. Changes in nitrogen leakage and surface runoff. The results showed that in maize growing season (compound fertilizer as base fertilizer, urea as top fertilizer, basal fertilizer level as 150kgN ha-1), N2O emission coefficient of whole growing season was 3.3% and NH3 volatilization loss rate was 10. 2%, nitrogen leakage rate and surface runoff loss rate were 11. 2% and 5. 1%, respectively. Nitrogen leakage was the main loss of base fertilizer, while ammonia volatilization and leakage were the main loss of top dressing nitrogen, indicating that nitrogen loss in different ways was mainly affected by nitrogen fertilizer varieties. Similarly, under the conditions of compound fertilizer as base fertilizer, urea as top fertilizer, basal fertilizer as 162 ha-1 and topdressing fertilizer as 108kgN.ha-1, the N2O emission coefficient of whole rice growing season is 1.5cm NH _ 3 volatilization loss rate is 9.7 and nitrate nitrogen leakage loss rate is 4.9. Because there is no drainage in the growing season of direct seeding rice, the nitrogen loss rate of surface runoff is zero. In this paper, according to soil types and climatic factors, the whole country is divided into eight regions. By collecting the published data on N _ 2O emission of NH _ 3 volatilization, nitrogen leakage and runoff from 2000 to 2012 in three major crops in China, rice, wheat and maize, By querying the meteorological data of China meteorological database, the model of nitrogen loss and nitrogen application in four ways after the correction of temperature and precipitation data was established. Based on the annual average amount of nitrogen applied and the area under cultivation for each of the three crops collected in each region, rice has been estimated for each year since 2000 in China. 灏忛害鍜岀帀绫崇殑骞冲潎N_2O 鎺掓斁閲忓垎鍒�涓� 41.73卤13.67Gg,44.52卤11.51Gg,72.33卤11.65Gg;NH3鎸ュ彂閲忓垎鍒�涓� 1035.33卤264.54Gg,331.28卤81.13Gg,951.71卤144.03Gg;鎬绘爱寰勬祦閲忓垎鍒�涓�263.75卤60.14Gg,329.98卤64.43Gg,89.23卤32.03Gg;鍜屾，

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