Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, P.O. Box 2713, Doha, Qatar.
Environmental Science Center, Qatar University, P.O. Box 2713, Doha, Qatar.
Am J Bot. 2021 Mar;108(3):411-422. doi: 10.1002/ajb2.1631.
Climate change is having major impacts on alpine and arctic regions, and inter-annual variations in temperature are likely to increase. How increased climate variability will impact plant reproduction is unclear.
In a 4-year study on fruit production by an alpine plant community in northern Sweden, we applied three warming regimes: (1) a static level of warming with open-top chambers (OTC), (2) press warming, a yearly stepwise increase in warming, and (3) pulse warming, a single-year pulse event of higher warming. We analyzed the relationship between fruit production and monthly temperatures during the budding period, fruiting period, and whole fruit production period and the effect of winter and summer precipitation on fruit production.
Year and treatment had a significant effect on total fruit production by evergreen shrubs, Cassiope tetragona, and Dryas octopetala, with large variations between treatments and years. Year, but not treatment, had a significant effect on deciduous shrubs and graminoids, both of which increased fruit production over the 4 years, while forbs were negatively affected by the press warming, but not by year. Fruit production was influenced by ambient temperature during the previous-year budding period, current-year fruiting period, and whole fruit production period. Minimum and average temperatures were more important than maximum temperature. In general, fruit production was negatively correlated with increased precipitation.
These results indicate that predicted increased climate variability and increased precipitation due to climate change may affect plant reproductive output and long-term community dynamics in alpine meadow communities.
气候变化对高山和北极地区产生了重大影响，且年际间的温度变化可能会增加。增加的气候多变性将如何影响植物繁殖尚不清楚。
在瑞典北部高山植物群落果实产量的 4 年研究中，我们应用了三种增温方式：（1）开顶式气室（OTC）的静态增温水平，（2）加压增温，即逐年逐步增加增温，（3）脉冲增温，即一次性的更高增温脉冲事件。我们分析了萌芽期、结果期和整个果实生产期的每月温度与果实产量之间的关系，以及冬季和夏季降水对果实产量的影响。
年际和处理对常绿灌木、紫菀和柳兰的总果实产量有显著影响，处理和年份之间有很大的差异。年际而非处理对落叶灌木和禾本科植物有显著影响，这两种植物在 4 年内都增加了果实产量，而杂草则受到加压增温的负面影响，但不受年份的影响。果实产量受前一年萌芽期、当年结果期和整个果实生产期的环境温度影响。最低温和平均温度比最高温度更为重要。总的来说，果实产量与降水增加呈负相关。
这些结果表明，由于气候变化预计会增加气候多变性和降水，这可能会影响高山草甸群落中植物的繁殖产量和长期的群落动态。
