施肥对免耕旱作燕麦田土壤温室气体排放的影响

Effects of Fertilization on Greenhouse Gas Emissions in No-tillage and Dry-Oat Field

采用静态箱-气相色谱法,研究了不施肥(CK)、施氮肥(N)、施磷肥(P)、施钾肥(K)、氮磷肥配施(NP)和氮磷钾肥配施(NPK)5种施肥处理对免耕旱作燕麦田土壤温室气体排放的影响,以期为当地农田生态实现可持续发展提供科学依据。结果表明,各处理土壤CO_2排放通量随燕麦生育期均呈先增加后减小的趋势,拔节期出现峰值;不同施肥处理CO_2平均排放通量均高于不施肥处理,其中氮磷钾配施、氮磷配施和施氮处理与不施肥处理间差异显著;各处理土壤CH_4排放通量在全生育期内均表现为吸收特征,呈"反S型"变化,全生育期氮磷钾、氮磷和施氮处理CH_4平均吸收通量显著高于不施肥处理,分别是不施肥处理的1.30、1.25、1.15倍,三者之间差异不显著;各处理N_2O排放通量全生育期内均表现为排放源,呈先增后减的趋势,各处理N_2O平均排放通量表现为施氮>氮磷配施>氮磷钾配施>施磷>施钾>不施肥,其中施氮、氮磷配施、氮磷钾配施与不施肥处理差异显著,施磷、施钾与不施肥处理差异不显著;氮磷钾配施、氮磷配施、施氮、施磷、施钾处理综合温室效应分别比不施肥处理高22.3%、15.6%、12.8%、10.1%和4.7%,除施钾处理外,其他施肥处理均与不施肥处理差异显著。

Effects of fertilization on greenhouse gas emissions in no-tillage and dry-oat field were studied to pro- vide scientific basis for sustainable development of the local farmland. Soil greenhouse gas emissions of different fertilizer treatments including CK, P, K, NP and NPKwere measured by using static chamber-gas chromatograph- ic techniques. The result showed that soil CO2 fluxes in all treatments first increased and then decreased with the advance of oat growth stage,and the highest value appeared in the jointing stage. The average CO2 fluxes in differ- ent fertilizer treatments were higher than that in no fertilizer treatment, and there were significant differences be- tween three treatments （NPK, NP and N） and CK. Soil CH4 fluxes performed absorption characteristics in the whole growing period and the change regulation showed a reversed S shape. The average soil CH4 fluxes in NPK, NP and N treatments were significantly higher than that in no fertilizer treatment. The average soil CI-L fluxes in NPK, NP and N treatments were 1.30 times, 1.25 times and 1.15 times of CK respectively, and there were no sig- nificant differences between the three treatments. Soil N20 fluxes in all treatments performed emission source. It increased first and decreased then in the whole growing period. The average soil N20 fluxes in different treatment was in the increasing order of CK, K, P, NPK, NP and N. There were significant differences between three treat- ments（NPK, NP and N） and CK, and the three treatments had no significant differences. Phosphate fertilizer and potash fertilizer had few effects on it. Compared with CK, the integrated emission effect in NPK, NP, N, P and K treatment increased by 22.3%, 15.6%, 12.8%, 10.1% and 4.7%, respectively. There was significant difference between all fertilizer treatments and no fertilizer treatment except K treatment.