Forest Change in a Boreal Transition Region: Productivity, Nutrient Cycling and Biodiversity at Multiple Scales

9524078北方过渡地区的帝国森林变化：多尺度生产力、养分循环和生物多样性。人类社会的行动对世界各地的北方森林产生了深远的影响。土地利用，如木材采伐、气候、二氧化碳水平升高和火灾制度的改变，都有助于北方森林生态系统的组成(物种构成)、功能和生物多样性的变化。这个项目将评估森林是如何变化的，以及为什么会与伐木、火灾、二氧化碳升高和气候等关键区域和全球因素有关。为什么我们更好地了解这些影响目前是什么，以及未来可能会是什么？首先，北方森林作为森林产品工业的纤维来源，对美国和全球的经济福祉做出了贡献。其次，北方森林在全球碳循环中扮演着重要角色，从而影响全球二氧化碳水平。第三，北方森林是地球上最大的完整森林生物群，比任何其他森林生物群都拥有更好的动植物平衡。最后这一点在经济上和生态上都很重要。北部森林覆盖率较高的地区由当地人使用，并支持依赖野生动物、清洁水和自然美景的日益增长的娱乐产业。改变北方森林生产力或长期土壤肥力的变化，或改变这些地区动植物多样性的变化，可能正在发生。然而，一个关键的问题是，他们正在以有利于、中立或有害于我们在这些地区的长期目标的方式改变这些进程，同样关键的是这种变化的规模问题，无论是在林地基础上还是对整个森林区域而言。这些问题的答案将在两个主要方面帮助我们。首先，它们有助于我们全面评估森林对全球大气变化及其相关气候影响的反应。第二，它们能够在范围、类型、时机和景观配置方面更好地设计木材采伐(和其他管理选择)。在对环境的损害最小的情况下，究竟可以采伐多少木材，如何以及在哪里进行，这是一个非常困难的问题(通常也很有争议)，但对社会来说是一个重要的问题。

9524078 Reich Forest Change in a Boreal Transition Region: Productivity, Nutrient Cycling and Biodiversity at Multiple Scales. The actions of human society have profound impacts on boreal forests worldwide. Land use such as timber harvesting, climate, elevated carbon dioxide levels, and altered fire regimes all contribute to changes in the composition (species make-up), function and biodiversity of boreal forest ecosystems. This project will assess how forests are changing, and why, in relation to key regional and global factors such as logging, fire, elevated carbon dioxide, and climate. Why is it important that we better understand what those impacts are at present, and may be in the future? First, boreal forests contribute to the economic well being of the USA and globally as a source of fiber for the forest products industry. Second, boreal forests play an important role in global carbon cycles, and thus influence global carbon dioxide levels. Third, boreal forests represent the largest intact forest biome on the planet and house a better balanced flora and fauna than any other forest biome. This last point has importance economically as well as ecologically. Regions with major boreal forest coverage are used by native peoples and support a growing recreational industry that depends on wildlife, clean water, and natural beauty. Changes that alter the productivity or long-term soil fertility of boreal forests, or that alter the plant and animal diversity of such regions, are likely occurring. However, a critical question is whether they are altering such processes in ways that are beneficial, neutral, or detrimental to our long-term goals for such regions, and equally critical is the question of the magnitude of such changes, both on a forest stand basis and for a forested region as a whole. The answers to such questions will help us in two main ways. First they aid in our overall assessment of forest response to global atmospheric change and its associated climate impacts. Secon d, they enable better design of timber harvesting (and other management options), with respect to scope, type, timing, and landscape configuration. Just how much timber harvesting can occur, and how and where, with minimal detriment to the environment, is a very difficult question (and usually quite controversial) but one that is important to society .