Estimating the Direct and Indirect Impacts of Climate Change On Small Wetland Ecosystems

估计气候变化对小型湿地生态系统的直接和间接影响

• 批准号: RGPIN-2020-07007
• 负责人: Houlahan, Jeff
• 金额: $ 3.42万
• 依托单位: University of New Brunswick
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=744878
• 关键词: Estimating; Direct; Indirect; Impacts; Climate

The Intergovernmental Panel on Climate Change released a report in 2018 estimating the consequences of the 1.5o C increase in temperature that we are almost certain to see in the next 25 years. The evidence is unequivocal that our climate is changing, that the changes are caused by human activities and the economic and social consequences will be large and negative. Mitigation of climate change impacts is going to require reasonably accurate predictions of the effects of climate change over the next 30-100 years. Changes in temperature and precipitation are likely to have both direct and indirect impacts on small wetland communities. Direct impacts are caused by pushing some organisms outside the range of temperatures or hydro-period where they can thrive or persist and indirect impacts are caused by changing biological interactions among species within aquatic systems. One example of such a potential indirect effect caused by changes in interactions, is between green frog and wood frog tadpoles. Green frogs and wood frogs benefit from the direct effect of deeper, longer lasting ponds due to increased precipitation because they are less likely to undergo mortality as a result of pond drying. However, the beneficial effect on wood frogs of increased hydro-period may be offset or overwhelmed by increased consumption of wood frog eggs by green frog tadpoles or increased transmission of Rana virus from green frog larvae to wood frog larvae. The Houlahan lab at the University of New Brunswick in Saint John will use wood frogs in natural ponds as a model system supplemented by laboratory experiments and observations of unmanipulated systems, to examine the direct and indirect effects of warming. We will increase the temperature of six natural ponds at the Long-term Experimental Wetlands Area on CFB Gagetown in New Brunswick by ~ 6 degrees C using solar panel heating units and polyethylene tubing. Each of the manipulated ponds will be paired with a similar control pond. We will measure wood frog growth, development, survival, amphibian disease prevalence and virulence, and green frog and dragonfly larval abundance in treatment and control ponds. We will build predictive models describing the direct impacts of temperature on wood frog growth, development and survival and indirect impacts through effects of warming on wood frog predators such as green frogs and dragon fly larvae, and wood frog diseases such as chytridiomycosis and Rana virus. These predictive models will be used by policymakers and conservation professionals to develop policies and strategies to mitigate climate change impacts in natural systems.

政府间气候变化专门委员会在2018年发布了一份报告，估计未来25年我们几乎肯定会看到气温上升1.5摄氏度的后果。证据确凿地表明，我们的气候正在变化，这些变化是由人类活动引起的，其经济和社会后果将是巨大的和负面的。缓解气候变化的影响将需要对未来30-100年内气候变化的影响做出相当准确的预测。温度和降水的变化可能会对小型湿地群落产生直接和间接的影响。造成直接影响的原因是将某些生物推到温度或水期之外，使其能够繁衍或持续存在，间接影响是由于水生系统内物种之间的生物相互作用发生变化造成的。这种由相互作用变化引起的潜在间接影响的一个例子是绿色青蛙和林蛙蝌蚪之间的影响。绿色青蛙和林蛙受益于更深、更持久的池塘的直接影响，因为降雨量增加，因为它们不太可能因池塘干燥而死亡。然而，增加水期对林蛙的有利影响可能会被青蛙蝌蚪对林蛙卵的消耗增加或绿蛙幼虫向林蛙幼虫传播拉纳病毒的增加所抵消或盖过。圣约翰新不伦瑞克大学的胡拉汉实验室将使用天然池塘中的林蛙作为模型系统，并辅之以实验室实验和对未受操纵的系统的观察，以研究气候变暖的直接和间接影响。我们将使用太阳能电池板加热装置和聚乙烯管道，将新不伦瑞克CFB加吉敦长期实验湿地地区的六个天然池塘的温度提高约6摄氏度。每个人工操作的池塘都将与一个类似的控制池塘配对。我们将在处理和对照池塘中测量林蛙的生长、发育、存活、两栖动物疾病流行和毒力，以及青蛙和蜻蜓幼虫的丰度。我们将建立预测模型，描述温度对林蛙生长、发育和生存的直接影响，以及通过变暖对林蛙捕食性动物(如青蛙和蜻蜓幼虫)以及林蛙疾病(如壶菌病和拉纳病毒)的影响而产生的间接影响。这些预测模型将被政策制定者和保护专业人员用来制定政策和战略，以减轻气候变化对自然系统的影响。