Carbon sequestration consequences of spruce budworm outbreaks and control in eastern Canadian forests

森林在从大气中去除二氧化碳并将其储存在土壤中方面发挥着重要作用--因此， 对抗大气中二氧化碳使气候变暖的趋势。我们会问， 云杉芽虫是一种主要的森林害虫，它使数百万公顷的针叶树落叶并死亡， 过程在落叶的森林中，死针叶和芽虫的粪便可能会在短期内增加碳的含量 流向土壤。然而，从长远来看，落叶林减少二氧化碳排放的能力较低， 更薄的树冠意味着更温暖的土壤，因此，潜在地，更多的储存释放。 土壤中的碳。我们将研究这些影响和他们的相互作用，通过比较森林样地， 与类似的，附近的地块已被保护免受芽虫的损害， 空中喷洒生物杀虫剂Btk。我们将测量从地面落下的针和毛毛虫的粪便， 测量土壤核心中的碳含量，并测量二氧化碳的排放量 从土壤中的微生物。我们还将测量“菌根”真菌的丰度-- 它与树根结成伙伴关系，从树上接收含碳糖并将其转移到土壤中。 总之，这些测量将帮助我们了解蠕虫爆发如何改变碳循环， 森林，以及我们如何使用Btk治疗干预，以保护森林的碳储存作用。这 这项研究将涉及知名科学家和来自纽约大学的学生 不伦瑞克，加拿大林业局，加拿大农业和农业食品。

Forests play an important role in removing carbon dioxide from the atmosphere and storing it in soil - thus countering the tendency for atmospheric carbon dioxide to warm our climate. We will ask how outbreaks of spruce budworm, a major forest pest that defoliates and kills conifers over millions of hectares, alter this process. In defoliated forests, dead needles and budworm feces likely provide a short-term boost in carbon flow to soils. However, in the longer term, defoliated forests are less able to remove carbon dioxide from the atmosphere, and the thinner tree canopy means warmer soils and therefore, potentially, more release of stored carbon from the soil. We will study these effects and their interactions by comparing forest plots that have been defoliated by budworm with similar, nearby plots that have been protected from budworm damage by aerial spray with a biological insecticide, Btk. We will measure the fall of needles and caterpillar feces from the canopy to the ground, measure carbon content in soil cores, and measure the emission of carbon dioxide from microbes in the soil. We will also measure the abundance of "mycorrhizal" fungi - fungi that form partnerships with tree roots and which receive carbon-containing sugars from the tree and move them into soil. Together, these measurements will help us understand how budworm outbreaks change the carbon cycle in forests, and how we can use Btk treatments to intervene to protect the carbon-storage role of the forest. This research will involve both established scientists and students in training from the University of New Brunswick, the Canadian Forest Service, and Agriculture and Agri-Food Canada.