不同利用方式下高寒草甸植被生物量分配格局

Vegetation biomass allocation relationships in the different utilization patterns in alpine meadow

为明晰高寒草甸生态系统生物量之间的分配关系,选取自由放牧(FG)、休牧(RG)、禁牧(BG)、一年生人工草地(OAT)、多年生人工草地(PF)5个不同利用方式下的高寒草甸,对地上地下生物量、凋落物量及植被特征进行测定和分析。结果表明:不同利用方式下的高寒草甸根冠比差异显著;PF利用方式下的高寒草甸根冠比显著低于其他利用方式,FG利用方式下高寒草甸拥有最大的根冠比,均值为15.74,RG和BG利用方式下的高寒草甸根冠比大小次之,均值分别为10.12和9.81;对不同利用方式下高寒草甸地上、地下生物量相关关系的分析表明,RG、NG、OAT及PF利用方式下的高寒草甸的地上与地下生物量之间均呈明显的幂函数相关关系;对不同利用方式下高寒草甸物种多样性与地上生物量相关关系的分析表明,RG,NG和PF利用方式下的高寒草甸物种多样性与地上生物量之间呈明显的负二次函数关系。试验为不同利用类型草地地下生物量的准确估算提供了依据。

In order to clarify the distribution relationships between aboveground biomass and underground biomass,and to help researchers accurately calculate the underground biomass of alpine meadow ecosystem,five treatments including free grazing(FG),grazing rest(RG),banninggrazing(BG),annual artificial grassland(OAT),and perennial artificial grassland(PF)were set in this study.The results showed that root-shoot ratio was significantly different in all meadow utilization patterns,and root-shoot ratio under PF was significantly lower than other utilization patterns.There was the largest root-shoot ratio under FG,and the mean is 15.74.The root-shoot ratio was relatively higher under RG and BG and the mean of which were 10.12 and 9.81.In order the better to analyze how to estimate belowground biomass based on aboveground biomass,this study explored the relationship between above-and below-ground biomass.The result showed that belowground biomass was significantly positive correlated with aboveground biomass under RG,NG,OAT and PF.The power function fitted well with the relationship between belowground biomass and aboveground biomass for these four utilization patterns meadow.We also explored the relationship between diversity and aboveground biomass.The result showed that diversity was significantly positive correlated with aboveground biomass in RG,NG and PF.The negative quadratic function fitted well with the relationship between diversity and aboveground biomass for these three utilization patterns meadow.The results provide an evidence for the accurate estimation of belowground biomass of different utilization patterns of grassland in the future.