Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Regional Development and Environmental Response, Faculty of Resource and Environment, Hubei University, Wuhan, 430062, China.
Department of Biology/Aquatic Ecology, Lund University, Sölvegatan 37, S-223 62, Lund, Sweden.
Glob Chang Biol. 2017 Jan;23(1):108-116. doi: 10.1111/gcb.13405. Epub 2016 Jul 19.
Extreme climatic events, such as heat waves, are predicted to increase in frequency and intensity during the next hundred years, which may accelerate shifts in hydrological regimes and submerged macrophyte composition in freshwater ecosystems. Since macrophytes are profound components of aquatic systems, predicting their response to extreme climatic events is crucial for implementation of climate change adaptation strategies. We therefore performed an experiment in 24 outdoor enclosures (400 L) separating the impact of a 4 °C increase in mean temperature with the same increase, that is the same total amount of energy input, but resembling a climate scenario with extreme variability, oscillating between 0 °C and 8 °C above present conditions. We show that at the moderate nutrient conditions provided in our study, neither an increase in mean temperature nor heat waves lead to a shift from a plant-dominated to an algal-dominated system. Instead, we show that species-specific responses to climate change among submerged macrophytes may critically influence species composition and thereby ecosystem functioning. Our results also imply that more fluctuating temperatures affect the number of flowers produced per plant leading to less sexual reproduction. Our findings therefore suggest that predicted alterations in climate regimes may influence both plant interactions and reproductive strategies, which have the potential to inflict changes in biodiversity, community structure and ecosystem functioning.
极端气候事件，如热浪，预计在未来一百年内会增加频率和强度，这可能会加速淡水生态系统水文状况和淹没性水生植物组成的变化。由于大型植物是水生系统的重要组成部分，预测它们对极端气候事件的反应对于实施气候变化适应策略至关重要。因此，我们在 24 个户外围栏（400 升）中进行了一项实验，将平均温度升高 4°C 的影响与相同的升高量（即相同的总能量输入）分开，但类似于具有极端可变性的气候情景，在 0°C 和 8°C 之间波动目前的条件。我们表明，在我们研究中提供的中等养分条件下，平均温度升高或热浪都不会导致从植物占主导地位的系统转变为藻类占主导地位的系统。相反，我们表明，淹没性水生植物对气候变化的特定物种反应可能会严重影响物种组成，从而影响生态系统功能。我们的结果还表明，波动更大的温度会影响每株植物产生的花的数量，从而导致有性繁殖减少。因此，我们的研究结果表明，预测的气候模式变化可能会影响植物间相互作用和繁殖策略，从而有可能对生物多样性、群落结构和生态系统功能造成影响。
