An ecological perspective on biogeosciences (V2.0)

加拿大人面临的一个重要挑战是预测全球环境变化和/或替代土地使用和管理做法如何影响陆地生态系统的功能及其提供的服务。关注对碳和养分循环的生物控制是应对这一挑战的一种有希望的方式。我们可以通过采用几个科学领域的观点来做到这一点，每个领域都对自然现象提供了不同的见解。我自己的学术培训植根于应用生物地理学(即农业理学学士；森林科学博士；森林土壤管理博士后)。然而，在过去的20年里，我加入了各种研究小组，其中包括基础生态学家，他们向我灌输了对生态理论原理的补充观点。因此，我和我的学生培养了一种关于陆地生态系统功能的双重视角，使我们能够同时解决机械问题和理论问题。作为生物地质学家，我们研究的过程和机制是驱动陆地碳循环和养分循环的直接因素。作为生态学家，我们提出并依赖理论框架来理解这些相同现象的进化含义，以及推测、概括和做出大胆的预测。简而言之，作为生物地质学家，我们问的是某些现象是如何发生的；作为生态学家，我们问的是为什么会发生这些现象？这项探索资助计划的基础是这样一种信念，即通过放弃对陆地生物地球科学的生态学观点，可以获得大量的知识和技术。在这一框架内，我的学生和我将探讨四个研究主题：(I)全球变化对北方森林生态系统功能的影响，特别是生物固氮和土壤碳稳定；(Ii)基于特征的方法预测土壤有机物质分解的根际启动；(Iii)通过农业实践管理植物-丛枝菌根群落的结构和效益；(Iv)非本地蚯蚓在北方森林生态系统中创造的温室气体净平衡和生态级联。这一跨学科研究计划将在以下方面贡献重要的基础知识：(A)变化世界中北方森林生态系统的生物地球化学，(B)植物从本地土壤有机质中提取养分的方法，以及(C)入侵蚯蚓的广泛生态影响。这一新知识可能会指导未来的政策和土地管理决策，就像过去一样。

An important challenge facing Canadians is predicting how global environmental changes and/or alternative land use and management practices affect the functioning of terrestrial ecosystems and the services that they provide. Focusing on the biotic controls over carbon and nutrient cycling is a promising way to meet this challenge. We can do this by adopting the perspective of several scientific fields, each offering different insights into natural phenomena. My own academic training is rooted in the applied biogeosciences (i.e. BSc in agriculture; PhD in forest sciences; Postdoc in forest soil management). However, over the past 20 years I have joined various research groups that include fundamental ecologists who have infused in me a complementary outlook on ecological theory principles. My students and I thus foster a dual perspective on the functioning of terrestrial ecosystems that allows us to address both mechanistic and theoretical questions. As biogeoscientists, we study processes and mechanisms that are the proximate factors driving terrestrial carbon and nutrient cycles. As ecologists, we advance and rely upon theoretical frameworks to understand the evolutionary implications of these same phenomena, as well as to speculate, generalize and make bold predictions. Simply put, as biogeoscientists we are asking "how" do certain phenomena occur; as ecologists, we are asking "why" do they occur? This Discovery Grant proposal is predicated on the belief that substantial knowledge and technologies can be achieved by shedding an ecological perspective on terrestrial biogeosciences. Within this structure, my students and I will explore four research themes: (i) The effects of global changes on boreal forest ecosystem functions, notably biological nitrogen fixation and soil C stability; (ii) A trait-based approach for predicting the rhizosphere priming of soil organic matter decomposition; (iii) Managing the structure and benefits of plant-arbuscular mycorrhizal communities through agricultural practices; (iv) The net greenhouse gas balance and ecological cascades created by non-native earthworms in northern forest ecosystems. This transdisciplinary research program will contribute important and fundamental knowledge on (a) the biogeochemistry of boreal forest ecosystems in a changing world, (b) means by which plants can mine nutrients from native soil organic matter, and (c) broad-scale ecological impacts of invasive earthworms. This new knowledge is likely to guide future policy and land management decisions, as it has in the past.