Wolf Julie, Johnson Nancy C, Rowland Diane L, Reich Peter B
Departments of Environmental and Biological Sciences and the Merriam-Powell Center for Environmental Research, Northern Arizona University, Flagstaff, AZ 86011-5694, USA.
USDA-ARS, National Peanut Research Laboratory, Dawson, GA 31742-0509, USA.
New Phytol. 2003 Mar;157(3):579-588. doi: 10.1046/j.1469-8137.2003.00696.x.
• We enumerated arbuscular mycorrhizal (AM) fungal spore communities for 3 yr as part of a long-term CO enrichment experiment at Cedar Creek, Minnesota, USA. Complete factorial combinations of two levels of CO and N, and 16 perennial plant species grown in monoculture and 16-species polyculture were arranged in a split-plot design. • In 1998-2000, spore communities were quantified under monocultures of eight plant species. In 2000, measurements were expanded to include monocultures and polycultures of all of the plant species. • Under plant monocultures, only Glomus clarum responded significantly to CO elevation out of 11 species present. This response was not detectable under plant polycultures. Glomus clarum was also significantly more abundant under plant polycultures. Nitrogen addition had small negative effects on AM fungal spore abundance and species richness in 2000. The interaction of CO and N did not affect arbuscular mycorrhizal fungal spore communities. • We show that CO enrichment and plant species richness impact arbuscular mycorrhizal fungal community structure. These findings are important because altered symbiotic functioning may result.
• 作为美国明尼苏达州雪松溪一项长期二氧化碳富集实验的一部分，我们连续3年对丛枝菌根（AM）真菌孢子群落进行了计数。实验采用裂区设计，设置了两个水平的二氧化碳和氮的完全析因组合，以及16种多年生植物的单作和16种植物的混作。
• 1998 - 2000年，对8种植物的单作条件下的孢子群落进行了量化。2000年，测量范围扩大到包括所有植物物种的单作和混作。
• 在植物单作条件下，在所出现的11个物种中，只有明球囊霉（Glomus clarum）对二氧化碳浓度升高有显著反应。在植物混作条件下未检测到这种反应。在植物混作条件下，明球囊霉的数量也显著更多。2000年，添加氮对AM真菌孢子丰度和物种丰富度有较小的负面影响。二氧化碳和氮的交互作用未影响丛枝菌根真菌孢子群落。
• 我们表明，二氧化碳富集和植物物种丰富度会影响丛枝菌根真菌群落结构。这些发现很重要，因为可能会导致共生功能改变。
