非洲狗尾草人工草地植物量动态研究

2009～2010年，对不同刈割次数的非洲狗尾草人工草地地上和地下植物量进行了较为详细的研究。结果表明：在孕穗期刈割2次的非洲狗尾草人工草地地上、地下年净初级生产力最高，分别为3845．01g/m2DM和716．90g/m2DM；其次为孕穗期刈割1次的草地，分别为3386．12g/m2DM和674．23g／m2DM；最低的是全年不刈割的草地，分别是3260．97g/m2DM和653．63g／m2DM。草地之间地上年净初级生产力差异极显著（P〈0．01），地下年净初级生产力差异显著（P〈0．05）。全年不刈割的草地，以及孕穗期刈割1次、2次后的再生草草地，地上和地下植物量的变化均呈单峰曲线；地上植物量分别在9月上旬、9月中旬和9月底10月初达到峰值，峰值分别为3260．97g／m2DM、2813．76g／m2DM、2007．17g/m2DM；而地下植物量的峰值则几乎都出现在9月底10月初，分别为653．63g／m2DM、674．23g/m2DM、716．90g／m2DM，较地上植物量峰值出现的时间稍晚。

Dynamic Studies on Biomass in Artificial Grassland of Setaria Anceps Stap

During 2009 and 2010, the above and below ground biomass of artificial pasture Setaria of different cutting numbers had detailed study. The results showed that the above and below ground net primary productivity of artificial pasture Setaria of cutting two times were highest, were 3845.01g/m2DM and 716.90g/m2DM; Followed by cutting one times ,were 3386.12 g/m2DM and 674.23 g/m2DM; Without cutting were the lowest , were 3260.97 g/m2DM and 653.63 g/m2DM. The difference of above ground net primary productivity of pasture Setaria was very significant, The difference of below ground net primary productivity of pasture Setaria was significant, the above and below ground biomass of Without cutting, cutting one times and cutting two times showed that the peak time appeared by the end of September early October, the maxmium was 653.63g/mgDM, 674.23g/m2DM, 716.90g/mZDM. The peak of below ground biomass was later than that of above ground biomass.