增强的UV-B辐射对麦田生态系统能量累积和流动的影响

Effects of enhanced UV-B radiation on energy accumulation and energy flow of wheat field ecosystem

研究了大田栽培和自然光条件下 ,模拟 UV- B辐射 ( UV- B,2 80～ 31 5nm)增强对麦田生态系统能量累积和流动的影响。在 5.31 k J· m- 2 UV- B辐射下 ,春小麦群体不同生育期叶、茎、根、穗、粒生物量和总生物量显著降低 ,各部位热值没有显著变化 ,各部位能量累积和总能量累积显著降低。能量累积与生物量呈极显著正相关 ,而与热值没有显著的相关性 ,可能生物量比热值对能量累积的贡献更大。 UV- B辐射显著降低春小麦群体能量输出 ,可能导致麦田生态系统能量流动功能下降。

Influences of enhanced ultraviolet radiation (UV B,280~315 nm) on energy accumulation and energy flow of wheat field ecosystem were investigated under field conditions. Under 5.31 kJ·m -2 UV B radiation, the biomass in leaves,stems,roots,spikes,grains and whole plant of spring wheat colonies decreased significantly at various developmental stages,the calorific values in various plant parts had no changed significantly,the energy accumulation in various plant parts and whole plant decreased significantly.Energy accumulation was positively ( P <0.01) correlated with biomass,while was not significantly correlated with calorific values.The contribution of biomass to energy accumulation might be more than that of calorific values.UV B radiation reduced significantly energy output of spring wheat colonies,might resulted in decreases in the function of energy flow of wheat field ecosystem.