Baranov Viktor, Lewandowski Jörg, Krause Stefan
Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany Faculty of Mathematics and Natural Sciences, Geography Department, Humboldt University of Berlin, Rudower Chaussee 16, 12489 Berlin, Germany
Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany Faculty of Mathematics and Natural Sciences, Geography Department, Humboldt University of Berlin, Rudower Chaussee 16, 12489 Berlin, Germany.
Biol Lett. 2016 Aug;12(8). doi: 10.1098/rsbl.2016.0448.
While lakes occupy less than 2% of the total surface of the Earth, they play a substantial role in global biogeochemical cycles. For instance, shallow lakes are important sites of carbon metabolism. Aerobic respiration is one of the important drivers of the carbon metabolism in lakes. In this context, bioturbation impacts of benthic animals (biological reworking of sediment matrix and ventilation of the sediment) on sediment aerobic respiration have previously been underestimated. Biological activity is likely to change over the course of a year due to seasonal changes of water temperatures. This study uses microcosm experiments to investigate how the impact of bioturbation (by Diptera, Chironomidae larvae) on lake sediment respiration changes when temperatures increase. While at 5°C, respiration in sediments with and without chironomids did not differ, at 30°C sediment respiration in microcosms with 2000 chironomids per m(2) was 4.9 times higher than in uninhabited sediments. Our results indicate that lake water temperature increases could significantly enhance lake sediment respiration, which allows us to better understand seasonal changes in lake respiration and carbon metabolism as well as the potential impacts of global warming.
虽然湖泊仅占地球总表面积的不到2%，但它们在全球生物地球化学循环中发挥着重要作用。例如，浅水湖泊是碳代谢的重要场所。有氧呼吸是湖泊碳代谢的重要驱动因素之一。在此背景下，底栖动物的生物扰动（沉积物基质的生物改造和沉积物的通气）对沉积物有氧呼吸的影响此前一直被低估。由于水温的季节性变化，生物活动可能会在一年的过程中发生变化。本研究使用微观实验来探究当温度升高时，生物扰动（由双翅目摇蚊科幼虫引起）对湖泊沉积物呼吸的影响如何变化。在5°C时，有摇蚊和没有摇蚊的沉积物中的呼吸作用没有差异，但在30°C时，每平方米有2000只摇蚊的微观环境中的沉积物呼吸作用比未栖息沉积物中的高4.9倍。我们的结果表明，湖泊水温升高可能会显著增强湖泊沉积物呼吸作用，这使我们能够更好地理解湖泊呼吸和碳代谢的季节性变化以及全球变暖的潜在影响。
