CAJ | 학술논문

相似性假说通过物种构成的相似性来解释物种丧失是如何影响生物量的变异性的,但还没有得到检验.本研究通过设置在青藏高原东部地区的高寒草甸植物群落中的74个永久样方,采集3年(1999～2001)植物生长高峰期的群落数据,试图检验物种构成的相似性是如何解释物种多样性对地上生物量年际变异性的影响.结果表明:随着物种丰富度增加,生物量变异性降低;而随着均匀度的增加,生物量的变异性尽管在均匀度中等程度时似乎保持在同一水平,但总体上呈下降趋势;物种构成上的相似性解释了地上生物量变异性的大部分,而且随着物种构成上的相似性的增加,生物量的变异性降低;物种丰富度和均匀度均与物种构成上的相似性没有显著相关关系.这些结果表明:尽管生物多样性的丧失可能不必导致物种丰富群落中物种构成上的相似性,但相似性与地上生物量的变异性的因果联系可能是稳健的,由于本研究是在自然群落中进行的,对物种构成的相似性没有进行直接控制,因此,要深入理解相似性是如何影响生物多样性对生态系统功能变异性的效应的机制,可能还需要直接对物种构成的相似性进行控制的实验研究.
상사성가설통과물충구성적상사성래해석물충상실시여하영향생물량적변이성적,단환몰유득도검험.본연구통과설치재청장고원동부지구적고한초전식물군락중적74개영구양방,채집3년(1999～2001)식물생장고봉기적군락수거,시도검험물충구성적상사성시여하해석물충다양성대지상생물량년제변이성적영향.결과표명:수착물충봉부도증가,생물량변이성강저;이수착균균도적증가,생물량적변이성진관재균균도중등정도시사호보지재동일수평,단총체상정하강추세;물충구성상적상사성해석료지상생물량변이성적대부분,이차수착물충구성상적상사성적증가,생물량적변이성강저;물충봉부도화균균도균여물충구성상적상사성몰유현저상관관계.저사결과표명:진관생물다양성적상실가능불필도치물충봉부군락중물충구성상적상사성,단상사성여지상생물량적변이성적인과련계가능시은건적,유우본연구시재자연군락중진행적,대물충구성적상사성몰유진행직접공제,인차,요심입리해상사성시여하영향생물다양성대생태계통공능변이성적효응적궤제,가능환수요직접대물충구성적상사성진행공제적실험연구.
The similarity hypothesis may explain how biodiversity loss influences variability in biomass of plant communities but remains untested.We collected data over a three-year period (1999～2001),at the end of July during the peak of plant growing season,from 74 permanent plots in a natural alpine meadow located in the eastern Qinghai Tibetan Plateau.The objective was to test how similarity in species composition can explain the effects of species diversity on interannual variability in total aboveground biomass.Variability in total aboveground biomass per plot,decreased as species richness increased,and it also showed an overall decline as evenness increased although it appeared to stay at about the same level over the intermediate range of evenness.Similarity in species composition explained most of the variability in total aboveground biomass,and increased similarity in species composition reduced interannual variation in total aboveground biomass.Species richness and evenness were unrelated to similarity in species composition.These results indicate that the causal relationship between similarity and variability in total aboveground biomass may be robust,although biodiversity loss may not necessarily lead to decreased similarity in species composition in species-rich communities such as the alpine meadows of the Eastern Tibetan Plateau.Therefore,understanding how similarity influences the effects of biodiversity on variability in ecosystem functioning would require directly manipulated experiments for similarity in species composition.