论文部分内容阅读
关于有作物的土壤有机质分解速度下降的原因,以往是根据作物的蒸腾作用使土壤水分损失而导致微生物活性下降来解释的。作者用~(14)C示踪种黑麦一年的土壤,对大麦土壤的有机质分解效应进行研究之后认为,上述说法不能解释有机质分解速度为何普遍下降。试验着重研究植株生长对有机质分解的效应。~(14)C示踪土壤的配制是采用Murayama等(1979)的技术,~(14)C示踪黑麦草于田间温度下在土壤中培育一年。土样在不同时间采集,晾干后过50目筛,经540天贮存后用。其C含量为4.8％,~(14)C比强为5.2μCi/gC。土样用蒸
The reason why the rate of decomposition of organic matter in soils with crops has decreased has been explained in the past by a decrease in microbial activity due to loss of soil moisture due to the transpiration of crops. The authors used ~ (14) C to trace the soil of rye for one year and studied the decomposition effect of organic matter in barley soils. This conclusion can not explain why the rate of decomposition of organic matter generally declines. The experiment focuses on the effect of plant growth on the decomposition of organic matter. ~ (14) C Tracer soil was prepared using the technique of Murayama et al. (1979), and ~ (14) C tracing of ryegrass in soil for one year at field temperature. Soil samples collected at different times, dried over 50 mesh sieve, after 540 days of storage. The C content was 4.8% and the ~ (14) C ratio was 5.2μCi / gC. Soil samples with steam