关键词: 小麦凋落物, 分解残留物, 线性关系

Abstract: Based on the measurement of decomposition rate of wheat litter, dynamics of four nutrient elements, N, P, Ca and S, in remained decomposed organic matter of wheat litter had been analyzed quantitatively. Results showed that the nutrient concentration of N, P, Ca and S in remained organic matter of decomposed wheat litter increased with the proceeding of decomposition. If the concentration of elements were denoted with the ratio of the respective amount of element to remained organic matter of decomposed wheat litter and the time of litter decomposition denoted with the number of days of soil temperature greater than 0℃, the correlation between element concentration (y) and day number (x) can be expressed by the following linear models, respectively: y_N=0.4127+0.00223x_N (r=0.976) y_P=0.0697+0.0000677x_P (r=0.854) y_Ca=0.388449+0.0029x_Ca (r=0.929) y_S=0.0548+0.00152x_S (r=0.967) Except for P, the correlation coefficients of the rest were greater than 0.9. It showed that there were a reliable relationship between the element concentration and the day number. These linear relationships were helpful for further research into the element exchange between crop and soil. However, it was noticeable that the correlation between element concentration and day number at both beginning and end of the observation were poor. This is perhaps due to the difference of initial element content in wheat litter.

Key words: Wheat litter, Remained organic matter, Linear correlation