摘要
摘要:土壤类型对于农田氨挥发影响较大，而关于砂姜黑土农田氨挥发特征及排放系数研究相对较少，不利于区域性农田土壤氨排放清单的准确评估。基于此，选取豫南典型砂姜黑土为研究对象，设置不施肥(CK)、传统施肥(TR)、优化施肥(OPT)、再优化施肥(ZOPT)和缓控肥(HK)5种施肥处理，利用密闭海绵法，探究砂姜黑土农田不同施肥方式下冬小麦-夏玉米轮作土壤氨挥发特征，并尝试确定氨排放系数。结果表明：砂姜黑土传统施肥条件下冬小麦季土壤氨挥发量为11.1 kg·hm^-2，夏玉米季氨挥发量为13.4 kg·hm^-2，说明夏玉米季是砂姜黑土冬小麦-夏玉米轮作农田氨的高排放时期。对比不同处理的氨挥发量，发现ZOPT和HK处理冬小麦季和夏玉米季的氨挥发量显著低于其他处理(P < 0.05)，其次为OPT处理，TR处理的氨挥发量最高。HK处理的氨排放系数最低，其中冬小麦季和夏玉米季分别为1.7%和1.5%，显著低于其他处理(P < 0.05)；其次为ZOPT和OPT处理，其氨排放系数冬小麦季分别为2.1%和2.6%，夏玉米季分别为2.6%和3.6%；TR处理的氨排放系数最高，冬小麦季和夏玉米季分别为3.6%和4.7%。不同施肥处理氨挥发量与施肥量的拟合结果表明，随施肥量增加，冬小麦-夏玉米轮作农田氨挥发显示出较强的线性增长趋势，其中夏玉米季和冬小麦季的R²分别为0.934和0.931，说明该区域砂姜黑土传统施肥量的氨挥发未出现明显的激发性增长现象。本研究结果可为砂姜黑土区冬小麦-夏玉米轮作农田氮肥利用率的提高和氮排放清单的估算提供依据。
Abstract:Soil type affects farmland ammonia volatilization, but few studies have examined ammonia volatilization characteristics and emission coefficients. Therefore, the accurate inventory of regional farmland soil ammonia emissions is disadvantaged. Lime concretion black soil found in southern Henan, China, was used to explore the ammonia volatilization characteristics of winterwheat-summer maize-rotated cropland by the closed-sponge method. The soil was unfertilized (CK) or treated with traditional fertilizer (TR), optimized fertilizer (OPT), re-optimized fertilizer (ZOPT), or slow-controlled fertilizer (HK), and the ammonia emissions coefficient was determined. The results showed that the winter wheat and summer maize ammonia volatilization amounts using the traditional fertilizer treatment were 11.1 and 13.4 kg·hm^-2, respectively. Summer maize ammonia emission was 21% higher than winter wheat, indicating that the summer maize season was a high-volume period. Winter wheat and summer maize treated with HK and ZOPT had the lowest ammonia emission coefficients (HK:1.7% for winter wheat, 1.5% for summer maize; ZOPT:2.1% for winter wheat, 2.6% for summer maize; P < 0.05), the OPT treatment had moderate coefficients (2.6% for winter wheat, 3.6% for summer maize), and the TR treatment had the highest coefficients (3.6% for winter wheat, 4.7% for summer maize). The ammonia emissions fertilization gradients and fertilization amounts were plotted, and the ammonia volatilization amounts under variable fertilization treatments were linear (R²:0.931 for winter wheat, 0.934 for summer maize). These results may help to improve nitrogen fertilizer use and the ammonia emission inventory and provide basis for nitrogen emission estimation of winter wheat-summer maize rotation in lime concretion black soil croplands.



PDF全文下载地址:

http://www.ecoagri.ac.cn/article/exportPdf?id=14a8f115-d929-4fff-ba16-dd2da873923a