黑土区春小麦群体物质和能量积累研究

Study on Matter Accumulation and Energy Flow of Spring Wheat Population in the Black Soil Area

利用大田和实验室测定的方法,测定黑土区春小麦群体根、茎、叶、穗等物质和能量在整个生育期的积累过程,旨在为黑土区农业生态系统研究提供实测依据。结果表明,在整个生育期中,春小麦不同器官鲜物质积累的最大值出现的时期各异;除叶和20 cm以下根外,其它器官干物质累积均随生长发育而增加;各器官含水量差异较大,但都随生长而降低;每个器官能量的累积总量并不都是随生长发育而持续增长,且器官间单位干物质所含能量差异较大,变化范围为0.9×10~4 J·g^(-1)(根,孕穗期)至1.5×10~4 J·g^(-1)(叶,三叶期),根、秸秆、籽粒积累的能量分别为6.8×10~5、78.9×10~5和87.9×10~5 J·m^(-2),分别占总积累能量的3.9％、45.4％、50.7％。同实测法相比,计算法获得的秸秆能值高出31％。因此,测定法较计算法能更精确地反映能量在生态系统中的流动。

In order to provide basic data for studying agricultural eco-systems in the black soil area, the processes of matter accumulation and energy flow in root, stem, leaf and ear of spring wheat population at different stages of growth were measured by using the calorimeter Parr. The results showed that the largest fresh weight of different organs formed at different stages of growth. The dry matter in other organs accumulated increasingly with wheat growth except those in the leaf and root (20 cm under the surface of soil) ; The differences of the water content in different organs were marked great among them but all of them decreased with the growth of spring wheat; All the total energy that was accumulated in different organs did not continually increase with the growth of spring wheat, and the energy per unit of dry matter in different organs significantly varied from 0. 9×104 to 1. 5×104 J ·g-1. In the stage of harvest, the accumulated energy in root, straw and grains were 6. 8×105, 78. 9×105 and 87. 9×105 J·m-2, respectively, and the ratio of them to total energy were 3. 9% , 45. 4% and 50. 7% , respectively. Compared with the values measured, the energy calculated in straw was 31 percent higher. Hence, in order to accurately evaluate the energy flow, the method of energy measurement should be recommended.