有机肥对农田土壤二氧化碳和甲烷通量的影响

研究了不同有机肥施用(鸡粪、猪粪、牛粪)对夏玉米田土壤CO2和CH4通量的影响.结果表明，不同处理的CO2通量具有相同的季节变化趋势，受土壤温度和湿度的共同影响，土壤CO ₂通量和大气温度、地表温度、地下温度呈显著正相关，当温度不是限制因子的时候，CO₂通量和土壤水分含量呈显著正相关(P<0.05).玉米整个生长季大部分时间土壤为CH₄的吸收汇，源汇的变化受环境因子的影响，但是相关分析并不显著.不同处理的土壤CO₂季节平均排放通量为0.5124～0.8518 g·m^-2·h^-1，和CK₂相比，玉米种植促进了CO₂的排放，施用有机肥也增加了CO₂的排放，所有有机肥处理的平均排放通量和CK₂差异显著，但只有S₂和P₂和CK₁的差异显著.不同处理农田土壤CH4的季节平均通量为-0.0068～-0.0484 mg·m^-2·h^-1，有机肥施用抑制了土壤对CH₄的吸收，施肥量高抑制作用强，但是统计分析差异并不显著.

Effects of organic manures on CO2 and CH4 fluxes of farmland

This paper studied the effects of chicken manure, swine waste and cattle manure on the CO2 and CH4 fluxes of a farmland planted with summer maize. The results showed that the CO2 flux had the same trend under different organic manure application, which was influenced by soil temperature and soil water content. The flux was significantly related with air temperature, soil surface temperature and soil temperature (P < 0.05). When soil temperature was not a limiting factor, soil water content was significantly related with soil CO2 flux. At most maize growth stages, soil was a sink of CH4. The variation of CH4 source-sink was influenced by environmental factors, but the correlation was not significant. The mean seasonal flux of CO2 was from 0.5124 to 0.8518 g x m(-2) x h(-1), and that of CH4 was from - 0.0068 to - 0.0484 mg x m(-2) x h(-1). Compared with CK2, maize planting and organic manure application enhanced CO2 emission. The application of organic manures inhibited the CH4 uptake by soil, and higher application rate had a higher inhibitory effect.