Dr Phil started by asking whether resilience was a means to an end of sustainability or if sustainability simply not good enough not the right goal?. Resilience concept has been around for over 40 – 45 years which started with Horlin who was known as the father and started out as an entomologist. Resilience is most useful at the Eco-system level even though it can be used in individual aspect as well.  In forest context, resilience could be seen as the ability to persist under pressure, following stress, disruption or disturbance which can be accomplished through various resilience concepts. Such as : Robustness (resistance to change), Recovery (reliable return to previous state), Adjustment ((Some components, structure or functions change which may be temporary/ short term/ minor), Adaptation (major, long-term adjustment or permanent), Transformation (most components or structure changed but some function retained).

Robustness can be likened to a brick wall. Recovery is compared to a spring which when strained returns to its previous state. Adjustment is comparing a window being replaced with a bricked wall which causes the brick walls not to retain its function. Adaptability which attributes or reflects flexibility, function under a broad range of conditions or roles likened to the Swiss army knife An adaptation pathway is often achieved through behavioral (mostly animals) or physiological plasticity (plants and trees), genetic diversity, migration or sustainability. Transformation likened to toy transformers  (robot) also a squashy ball which suddenly becomes a handful of ribbons denoting a strong change in most components or structure but some components, structure or function retained.

Dr Phil Burton talked about lakes as eutrophic conditions or savannas  more dominated by trees or grasses . Ecological resilience within the context of multiple ecological domains and the width of this domain is important.

He talked about the evolution of resilience concepts: Adaptive capacity is the ability to remain in a stability domain, despite changes in the landscape or environment.

Dr Phil Burton gave a diagrammatic representation of the  classified challenges for five needle pine subalpine Woodlands into various categories: Pre-disposing factors, triggering factors, accelerating factors and outcomes. He spoke about spending some of his sabbatical leave at Nevada where he looked at the great basin bristlecone pine (pinus longaeva) which is known as the longest living tree (2000 – 3000 years old) but vulnerable to fire. He also spent some time in New Zealand’s native and farm forests which are quite adapted to some of their earthquakes and heavy rainfalls etc with very good diversity patterns. Also New Zealand plantations The need for more resilient forests is  not just natural abilities but also management practices.

In generalizing, he came to the conclusion that

  • Most tree species and forest types have been filtered by past disturbances, disruptions, stresses, and limiting factors.
  • Resilience is contingent on site, landscape context, other events, and may require decades (a long time) or centuries to be expressed.
  • Reliable robustness and recovery strategies have evolved under specific selective pressures
  • Adjustment and adaptive responses are more happenstance
  • Robustness strategies often entail “disturbance avoidance”
  • Rapid recovery is facilitated by eg. reproduction, seed dispersal
  • Healthy soils are really under appreciated
  • Novel disturbances, exotic pests, and fragmented populations compromise what had been successful resilience strategies
  • Tipping points often result from repeated, interacting, or cumulative disruptions, depend on critical population or remnant size.

Dr Phil outlined steps towards managing for resilience:

  • Identify, prioritize values to be sustained which may involve zoning, public consultations, socio-economic considerations
  • Characterize driving factors for each value which may involve research, look for evidence of thresholds
  • Project scenarios of likely changes/ threats which may involve simulation/ modelling
  • Conduct vulnerability analysis which involves response of values, their driving factors, to each scenario
  • Develop options to avoid, minimize or mitigate impacts which may involve decision points to switch from resistance to recovery, adjustment, adaptation or transformation
  • Implement programs for monitoring and feedback
  • Repeat

There are also current & future challenges (risk) to forest resilience which includes:

  • Climate change: milder winters, growing season moisture stress, facilitation of native pests and invasive species
  • Industrial expansion
  • Exotic invasive species: pathogens, insects
  • Over- exploitation: soil degradation and loss, missing components, habitat destruction and fragmentation.
  • Changing social demands and expectations: production,  local vs. global sourcing

He made a point that struck me that resilient ‘Eco system are not resilient to everything‘.

Moving forward he outlined a resilience management checklist:

  • Plan with risks in mind
  • Promote diversity at multiple levels
  • Maintain biological legacies, refugia and landscape
  • Maintain or create landscape barriers for threats
  • Trade-offs like fire risk reduction, forest nutrition, Carbon sequestration which can be addressed through zoning

He answered his questions really well and gave well detailed explanations.