摘要
在玉米生育期内测定了0~100cm土层土壤空气组成、土壤通气状况的呼吸强度.结果表明,裸地上壤空气中CO2浓度为0.1%~1.6%,覆膜处理为0.2~1.8%,平均比对照高32.39%,尚在作物生长适宜范围内.土壤O2含量与CO2浓度变化成负相关(裸地r=0.92,地膜r=0.79),裸地的O2浓度变化范围为13%~18%,覆膜上红为11%~17%,覆膜低于裸地4.96%.N2含量差异不显著.土壤呼吸强度与土壤深度呈幂函数关系,0~20cm耕层内,覆膜土壤明显高于裸地.覆膜对土壤结构有明显影响,与裸地相比,大团聚体(>0.25mm)和0.01~0.001mm粒级微团聚体含量减少,表层0~10cm土壤总孔隙度、气相率和通气孔隙度分别增加9.93%、24.56%和32.30%.
The results indicated that the CO2 concentration of the unmulched soil in the 0-100cm depth ranged from 0.1% to 1.6%,and that of mulched soil was 0.2% ̄1.8%.The latter was 32.39% by higher than the former on the average. Such CO2concentration in the soil air was still suitable for crop growth. The O2 rconcentration was inversely correlated with CO2 concentration in the soil air (unmulched soilr=0.92,mulched soil r=0.7).O2 concentration in the mulched and unmulched soil ranged from 11% ̄17% and 13% ̄18% respectively.By contrast,N2 concentration in soil air remained relatively steady,and there was no difference between the two treatments.The relationship between the soil respiratory intensity and the depth of soil layer appeared to be a power function. At the layer of 0-20cm, the soil respireation intensity in the mulched soil was obviously higher than that in the unmulchd soil. In contrast with unmulched soil, the amounts of >0.25mm and 0.05 ̄0.001mm microaggregates in mulched soil were reduced by 82.1% and 35.8%,respectively; soil total porosity of gaseous phase rate state and aeration porosity were increased by 9.93%,24.56% and 32.3% at the depth or 0-10cm,as compared with those of unmulched soil.
出处
《沈阳农业大学学报》
CAS
CSCD
1995年第2期146-151,共6页
Journal of Shenyang Agricultural University
基金
国家自然科学基金
关键词
地膜覆盖
土壤
空气
呼吸强度
团聚体
cultivation with plastic mulching
soil air
respiratory intensity
aggregate