Research into herbaceous bioenergy production has focused on identifying grassland systems that are both productive and temporally stable, where stability equals the ratio of mean biomass production to its temporal standard deviation. The question remains as to effects of community properties, including species richness, on temporal stability. We compared aboveground net primary productivity (ANPP) and the temporal stability in ANPP of unfertilized grassland planted either as a mixture of native perennial grass and forb species or monoculture of Panicum virgatum L. (switchgrass) in Texas, USA. ANPP varied in response to inter-annual variation (IAV) in precipitation. The precipitation effect on ANPP stability was mediated through two components of the influence of a single community property, community (species-abundance) weighted values of leaf dry matter content (LDMC), on productivity. These components include community LDMC and ANPP-LDMC regressions. Stability was similar between vegetation types but was regulated by different components of the LDMC effect on ANPP in mixture and switchgrass. Temporal stability in mixture depended mainly on ANPP variation that resulted from change in community LDMC. Stability of switchgrass depended primarily on ANPP variation that resulted from precipitation-caused change in ANPP-LDMC regressions. Stability declined as ANPP increased in mixture because LDMC variation increased when productivity was high. We find that ANPP and ANPP stability can be as great in an unfertilized planting of a switchgrass monoculture as diverse mixture of grassland species. Similar levels of stability can be achieved via different components of the LDMC effect on productivity.

草本生物能源生产的研究集中于确定具有生产力和时间稳定性的草地系统，其中稳定性等于平均生物质生产与其时间标准偏差之比。社区属性，包括物种丰富度，对时间稳定性的影响仍然存在问题。我们比较了地上净初级生产力（ANPP）和未施肥草地的ANPP的时间稳定性，这些未耕过草地是多年生原生草和Forb种的混合种植，或者是Panicum virgatum的单一栽培美国得克萨斯州的柳枝switch。ANPP随降水的年际变化（IAV）而变化。降水对ANPP稳定性的影响是通过单一群落特性影响的两个因素介导的，即叶片干物质含量（LDMC）的群落（物种-丰度）加权值对生产力的影响。这些组件包括社区LDMC和ANPP-LDMC回归。植被类型之间的稳定性相似，但受LDMC对混合草和柳枝AN中ANPP的不同影响。混合物的时间稳定性主要取决于由社区LDMC变化引起的ANPP变化。柳枝ability的稳定性主要取决于ANPP-LDMC回归中降水引起的变化而引起的ANPP变化。随着混合物中ANPP的增加，稳定性下降，这是因为当生产率高时LDMC变化会增加。我们发现，在柳枝mono单一栽培的未施肥种植中，ANPP和ANPP的稳定性与草原物种的各种混合物一样好。通过LDMC对生产率的不同影响，可以达到相似的稳定性。