Photo credit Bill Heath [email protected]
As silviculturalists, you and I are healers of the forest. At no other time in history have our knowledge, understanding and deep spiritual connection with the forest been more crucial for the well-being of this incredible place where we all live, this place we call Earth. As physicians do for humanity, we silviculturalists have a professional code of ethics (sensu Hippocratic Oath), and for most of us, a deeply personal commitment for the care for our forests so they are healthy, productive and resilient. We commit to this care while also delivering goods and services to society. The culture of the forest, or silviculture, is the most effective, creative and hopeful tool that humanity has for healing forest degradation and for mitigating and adapting to climate change (given that forests cover one-third of the Earth’s lands and affect all of the Earth’s systems). Society depends faithfully on us to practice successfully (to conserve forest function); our best performance is required. To be successful requires that silviculturalists are mindful of their intentions, the ecology of the forests, and how our practices affect whole systems. It requires that we maintain a deep spiritual connection to the forest, especially as that connection is challenged by human migration out of forests and into cities, and by the stresses of biodiversity loss and climate change. It requires that we remain open to new ideas, embrace uncertainty, and be ready to transform our practices to meet shifting societal goals and environmental conditions. The objective of this essay is to discuss a theory of mindful silviculture practice that honors the character of forests as complex adaptive systems. I use recent research on meta-networks to illustrate what complexity means. I follow with examples of mindful silviculture practices. I hope you find this essay inspiring, encouraging and helpful.
We all know that mindfulness is about being thoughtful, considerate and aware. But even more so, it is the avoidance of preconceived ideas that come with rigidity resulting from the strong filters and constraints on our perceptions of the world (Langer 1997). By keeping our minds open in this way, we are creative, conscientious and intentional in our actions (Siegel 2010). In the practice of silviculture, this means integrating observation, learning, knowledge, understanding and monitoring to make holistic management decisions in an uncertain environment. It means practicing silviculture with our minds rather than our guidebooks or institutional memes. It is similar to adaptive management in that it is based on a learning process to improve management outcomes. However, practicing mindful silviculture also requires intentional and holistic integration of the socio-ecological-economic system so that it remains adaptive and harmonious in its functioning. Mindful silviculture is responsive to uncertainty, working with it for the flexibility and diversity it brings rather than reducing it for short-term outcomes.
Like our minds and our societies, forests are complex adaptive systems (CAS) (Levin, 2005). Embracing the CAS concept has the potential to transform natural resource management from being simplistic to holistic (Messier et al. 2013), as it has for approaches to medicine, social and business organization, and information technology (Siegel 2010). Perhaps the easiest way to understand CAS is as a metaphor for understanding organizational behaviour – think, for example, of how your community or workplace functions. In CAS, low-level interactions among the parts or agents that make up the system (e.g., people) are fundamental to emergence of high-level order, or self-organization (e.g., functioning of the community or business). The properties of business organizations (e.g., performance, social responsibility, work-leisure balance) emerge from the interactions among people (e.g., interpersonal relationships) in the workplace and with their communities. We see in forest institutions, for example, that the essence of our greatest success is what individuals do and how they relate to each other, not what executives plan or policy makers enact. Our industry thrives on our professional ability to integrate social, economic and ecological values, and to be adaptive and harmonious rather than governed by rigid rules or chaotic markets.
Similarly, the interactions and interconnectedness of the parts and processes in forest ecosystems underlie their nature as CAS. The parts – the organisms, species, guilds – interact in networks across different genetic, trophic, spatial and temporal scales, and the relationships and feedbacks across these various scales create structure, cohesion and emergent properties (Lau et al. 2010). System memory, or the past structures and events (e.g., genes in seed-banks or old trees, nutrient and carbon capital, snags or coarse woody debris left from a previous disturbance, perennial mycorrhizal networks, or migratory bird occupation) and environmental variability (e.g., climate driven disturbances) are also important features of forests as CAS because they create and maintain diversity, productivity and system dynamics (Anand et al. 2010). Specifically, mycorrhizal networks form when the hyphae of mycorrhizas (literally ‘fungus-root’ symbioses) link together two or more plants of the same or different species. These function in (for example) the colonization of trees and plants, the uptake and transfer nutrients and water, communication among plants and other soil organisms via biochemical signals, the storage of carbon, and the stabilization of forest ecosystems (Simard et al. 2012).
Meta-networks are comprised of several nested, interacting network components, a concept that is useful for understanding cross-scale interactions in forest ecosystems. In forests, meta-networks can involve small-scale networks of mycorrhizal fungal species with specific niches in nutrient and water acquisition, which are nested within larger-scale networks of trees physically linked belowground through mycorrhizal fungi for community level cycling of water or nutrients, which in turn are nested within even larger-scale networks of interconnected forests, grasslands and riparian areas interacting through dispersal and energy fluxes, which are further nested within contiguous watersheds interacting through migrations and disturbance, and so on (Simard et al. 2013). These ecological networks also interact with social networks, where humanity lives in, relies on and cares for forests in community, institutional and global networks operating across a multitude of social scales. Organization in meta-networks can result from interactions through any of the nodes (e.g., fungi, trees, watersheds, community forests, countries) or links (e.g., energy and information fluxes, social learning, international agreements), and these interactions inform the whole system.
Meta-networks can be considered agents of self-organization because they provide avenues for cross-scale interactions and feedbacks from which emerge structure and function in CAS (Parrott 2010). From mediating nutrient, water and carbon fluxes, for example, mycorrhizal networks are foundational to the growth of trees and storage of carbon, which in turn drive the energetics of forest ecosystems. In addition to self-organization and emergence, the properties and processes of meta-networks integrate with other key properties and processes of CAS, including openness, uncertainty, adaptability, heterogeneity, diversity, hierarchy, non-linearity, memory, and sensitivity to initial conditions. When we isolate, manipulate or remove one of the key parts, networks or processes, we find that the effect ripples through the system to affect the other parts, networks and processes, often with unintended consequences. Disrupting network links by reducing the diversity of mycorrhizal fungi, for example, can reduce tree seedling survivorship or growth (Teste et al. 2009, Bingham and Simard 2012), ultimately affecting recruitment of old-growth trees that provide habitat for cavity nesting birds and mammals, and thus dispersed seed for future generations of trees (Edworthy and Martin 2013). Suppression of fire, high-grade logging, or removal of snags or coarse woody debris may also ultimately increase disturbance severity and reduce trees or tree-supported resource persistence that are prime sources of cavities (Drever et al. 2008). These changes can have direct consequences for human communities that depend on healthy forests for their socio-economic well-being. Conserving complex adaptive forest ecosystems, therefore, appears dependent on maintaining the diversity of its parts and processes, and the multiplicity of its interactions (Pimm 1984).
Disrupting mycorrhizal networks has had dramatic consequences for many forests. In southeast China, researchers recently discovered that absence of an appropriate soil microbial community was a key factor underlying mortality of the critically endangered tree species, Euryodendrom excelsum, and inoculation with mycorrhizal fungi increased survival rates of planted seedlings from 46 to 80% (Shen and Wang 2011). Similarly, in New Zealand, inoculation of Pseudostuga menziesii with ectomycorrhizal fungi native to North American habitat was pivotal in its success as an introduced species (Chu-Chou and Grace 1981). In British Columbia, the climatic envelope of interior Douglas-fir is projected to migrate northward and upward in the next century (Wang et al. 2012). At the same time, the current interior Douglas-fir forests are expected to undergo dramatic changes as regional climates become drier or wetter, hotter or cooler. We do not know whether the mycorrhizal fungi will migrate along with their host, and without an appropriate web of fungi to help the establishment of seedlings, forest may not recover from disturbance or migrate to new locations where climate becomes hospitable for them. By understanding the obligate role of mycorrhizal fungi in these forests, we can design creative forest practices that help the forests adapt and thrive in an uncertain climate. These practices could include, for example, retention of legacy trees, plants and soils, encouragement of natural regeneration along with planting, protection of dispersal agents, or assisted soil mycorrhizal inoculation of migrated trees.
The dynamical, structural and integrated properties and processes of ecosystems and social systems as CAS provide silviculturists with a powerful conceptual model for effecting change. That CAS are sensitive to initial conditions and memory means, for example, that silviculturists can cultivate healthy, adaptive and resilient forest ecosystems through harvesting and reforestation practices that conserve key parts and processes, such as legacies, meta-networks and energy flow. That forest ecosystems are integrated with our social networks means we have the opportunity to lead a new social mindfulness in forest stewardship and conservation. Conceptualizing and understanding forests as CAS provides us with a practical framework for practicing mindful silviculture. By understanding the parts and processes, and how they interact to produce emergent properties such as regeneration, biodiversity or productivity, we can create and learn about new silviculture practices that encourage forest adaptation and resilience to support thriving societies in an uncertain future.
Suzanne W. Simard is a Professor of Ecology in the Department of Forest Sciences and Conservation in the Faculty of Forestry at the University of British Columbia, Vancouver. She studies structural-functional relationships in forests and how they inform forest management, and leads a graduate training program on communication of global change research. Websites: http://profiles.forestry.ubc.ca/person/suzanne-simard/
Anand, M., Gonzalez, A., Guichard, F., Kolasa, J., and Parrot, L. 2010. Ecological systems as complex systems: challenges for an emerging science. Diversity 2: 395-410.
Bingham, M.A., and Simard, S.W. 2012.Ectomycorrhizal networks of old Pseudotsuga menziesii var. glauca trees facilitate establishment of conspecific seedlings under drought.Ecosystems, 15: 188-199.
Chu-Chou, M., and Grace, L.J. 1981. Mycorrhizal fungi of Pseudotsuga menziesii in the North Island of New Zealand. Soil Biology and Biochemistry, 13(3): 247-249.
Drever, M.C., Aitken, K.E.H., Norris, A.R., and Martin, L. 2008. Woodpeckers as reliable indicators of bird richness, forest health and harvest. Biological Conservation, 141: 624-634.
Edworthy, A.B., and Martin, K. 2013. Persistence of tree cavities used by cavity-nesting vertebrates declines in harvested forests. Journal of Wildlife Management, 77: 770-776.
Lau, M.K., Whitham, T.G., Lamit, L.J., and Johnson, N.C.. 2010.Ecological and evolutionary interaction network exploration: addressing the complexity of biological interactions in natural systems with community genetics and statistics. Journal of Intelligent and Fuzzy Systems 7: 19-27.
Levin, SA. 2005.Self-organization and the emergence of complexity in ecological systems. BioScience 55(12): 1075-1079.
Messier, C., Puettmann, K.J., and Coates, K.D. (editors). 2013. Managing Forests as Complex Adaptive Systems: Building Resilience to the Challenge of Global Change. First Edition. Routledge, NY. ISBN 978-0-415-51977-9. 369 pages.
Parrott, L. 2010. Measuring ecological complexity. Ecological Indicators 10: 1069-1076.
Pimm, S.L. 1984.The complexity and stability of ecosystems. Nature 307(5949): 321-326.
Seigel, D.J. 2010. The Mindful Therapist: A Clinician’s Guide to Mindsight and Neural Integration. First Edition. W.W. Norton & Co., NY. ISBN: 978-0-393-70645-1. 288 pages.
Shen, S.-K., and Wang, Y.-H. 2011. Arbuscular mycorrhizal (AM) status and seedling growth
response to indigenous AM colonisation of Euryodendron excelsum in China: implications for restoring an endemicand critically endangered tree. Australian Journal of Botany, 59: 460–467.
Simard, S.W., Beiler, K.J., Bingham, M.A., Deslippe, J.R., Philip, L.J., and Teste, F.P. 2012. Mycorrhizal networks: mechanisms, ecology and modelling. Fungal Biology Reviews, 26: 39-60.
Simard, S.W., Martin, K., Vyse, A., and Larson, B. (2013). Meta-networks of fungi, fauna and flora as agents of complex adaptive systems – Chapter 7, pages 133-164. In: Managing World Forests as Complex Adaptive Systems: Building Resilience to the Challenge of Global Change. Edited by Puettmann, K, Messier, C, and Coates, KD. Routledge, NY.
Teste, F.P., Simard, S.W., Durall, D.M., Guy, R.D., Jones, M.D., and Schoonmaker, A.L. 2009. Access to mycorrhizal networks and tree roots: importance for seedling survival & resource transfer. Ecology, 90: 2808-2822.
Wang, T., Campbell, E.M., O'Neill, G.A., Aitken, S.N., 2012. Projecting future distributions of ecosystem climate niches: uncertainties and management applications. Forest Ecology and Management, 279: 128-140.