Potential of forest fertilization to alleviate effects of climate change-induced insect infestation

由于气候引起的山松甲虫和西部松甲虫的大规模爆发，公元前内陆大部分森林工业所基于的松林将在2013年基本消失。这将摧毁许多林业支持的城镇的经济。作为增加木材供应的一项干预战略，不列颠哥伦比亚省森林和牧场部已提议广泛使用化肥，以加快现有林分的发展。考虑到去年BC已进行了1.7万公顷的作业施肥，另外还有900万公顷已经被松毛虫杀死，因此潜在的施肥面积非常大。欧洲、美国东北部和阿拉斯加的早期研究表明，向森林中添加高水平的氮素可以减少根的生长，扰乱微生物驱动的养分循环，增加淋溶，但这种影响因生态系统而异，目前的理论尚未预测到。我们的研究将会对。在松林和云杉林内部进行了一项现有的长期施肥试验，以测试林分水平的施肥是否扰乱了地下微生物群落及其提供的生态系统服务。我们将使用最先进的方法来确定施肥对(I)N、P、K、S和B的养分供应量以及(Ii)凋落物和土壤有机质的化学成分的影响。然后，我们将使用生化、同位素和分子方法来确定微生物群落是否‘适应’了这些新的条件，或者土壤细菌和真菌循环改变养分的能力是否受到了损害。这将是加拿大第一次将化肥引起的土壤有机质化学变化与森林土壤养分循环的相应变化联系起来。结果将使森林许可证持有者和政府监管机构能够确定允许促进生长和生态系统弹性的最佳组合的肥料制度。

Due to the massive, climate-induced outbreak of the Mountain and Western Pine Beetles, the pine forests on which much of the forest industry in interior BC is based will largely disappear by 2013. This will devastate the economies of many forestry-supported towns and cities. As an intervention strategy to increase timber supply, the BC Ministry of Forests and Range has proposed widespread use of fertilization to accelerate the development of already-existing stands. Given that 17,000 ha were operationally fertilized in BC last year, and that a further 9 million ha have already been killed by pine beetles, the potential area for fertilization is extremely large. Earlier research in Europe, the NE USA, and Alaska has demonstrated that addition of high levels of nitrogen to forests can reduce root growth, disrupt microbially-driven nutrient cycles, and increase leaching, but that effects vary by ecosystem and are not predicted by current theory. Our study would make use. of an existing long-term fertilization experiment in interior pine and spruce forests to test whether belowground microbial communities and the ecosystem services they provide are disrupted by stand-level fertilization. We | will use cutting-edge approaches to determine the effect of fertilization on (i) nutrient supply rates of N, P, K, S, and B and (ii) chemical composition of litter and soil organic matter. We will then use biochemical, isotopic, and molecular methods to determine whether the microbial community has 'adapted' to these new conditions or whether the ability of soil bacteria and fungi to cycle the altered nutrients has been compromised. This will be the first time in Canada that fertilizer-induced changes in the chemistry of soil organic matter will be linked to corresponding changes in nutrient cycling in forest soils. The results will allow forest licensees and government regulators to identify fertilizer regimes that allow the best combination of growth enhancement and ecosystem resilience.