Plant Functional Diversity Can Be Independent of Species Diversity: Observations Based on the Impact of 4-Yrs of Nitrogen and Phosphorus Additions in an Alpine Meadow.
Plant Functional Diversity Can Be Independent of Species Diversity: Observations Based on the Impact of 4-Yrs of Nitrogen and Phosphorus Additions in an Alpine Meadow.
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植物功能多样性可以独立于物种多样性：基于高寒草甸 4 年氮磷添加影响的观察
DOI：
10.1371/journal.pone.0136040
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发表时间：
2015
期刊：
影响因子：
3.7
通讯作者：
Du GZ
中科院分区：
文献类型：
--
作者：
Li W;Cheng JM;Yu KL;Epstein HE;Guo L;Jing GH;Zhao J;Du GZ
过去的研究已经广泛地记录了物种多样性随着营养物质的增加而减少的情况，然而功能多样性往往独立于物种多样性。通过田间试验，研究了青藏高原高寒草甸群落连续4年施氮磷肥((NH4)2HPO4)0、15、30和60gm-2yr-1(F0、F15、F30和F60)对功能多样性和物种多样性的影响及其与生产力的关系。为此，在每个施肥水平下，测定了30种常见树种的3个群落加权平均性状(比叶面积，SLA；成熟株高，mph；种子大小，SS)；量化了功能多样性的3个组成部分(功能丰富度，FRIC；功能均匀度，FEVE；Rao‘s指数，FRao)。结果表明：(1)随着施肥量的增加，物种多样性急剧下降，但功能多样性保持稳定；(2)群落加权平均性状(SLA和MPH)随施肥量的增加而显著增加；(3)地上生物量与功能多样性不相关，但与物种多样性和MPH显著相关。我们的结果表明，由于受精导致的物种多样性的减少并不会导致功能多样性的相应变化。在影响高寒草甸群落地上生产力方面，物种的功能一致性可能比功能多样性更重要，我们的结果也支持质量比假说，即优势物种的特征影响群落的生物量生产。
Past studies have widely documented the decrease in species diversity in response to addition of nutrients, however functional diversity is often independent from species diversity. In this study, we conducted a field experiment to examine the effect of nitrogen and phosphorus fertilization ((NH4)2 HPO4) at 0, 15, 30 and 60 g m-2 yr-1 (F0, F15, F30 and F60) after 4 years of continuous fertilization on functional diversity and species diversity, and its relationship with productivity in an alpine meadow community on the Tibetan Plateau. To this purpose, three community-weighted mean trait values (specific leaf area, SLA; mature plant height, MPH; and seed size, SS) for 30 common species in each fertilization level were determined; three components of functional diversity (functional richness, FRic; functional evenness, FEve; and Rao’s index of quadratic entropy, FRao) were quantified. Our results showed that: (i) species diversity sharply decreased, but functional diversity remained stable with fertilization; (ii) community-weighted mean traits (SLA and MPH) had a significant increase along the fertilization level; (iii) aboveground biomass was not correlated with functional diversity, but it was significantly correlated with species diversity and MPH. Our results suggest that decreases in species diversity due to fertilization do not result in corresponding changes in functional diversity. Functional identity of species may be more important than functional diversity in influencing aboveground productivity in this alpine meadow community, and our results also support the mass ratio hypothesis; that is, the traits of the dominant species influenced the community biomass production.