Eric B. Searle

Bio: Eric B. Searle is an academic researcher. The author has contributed to research in topics: Forest management. The author has an hindex of 1, co-authored 2 publications receiving 1 citations.

Simulating the Effects of Intensifying Silviculture on Desired Species Yields across a Broad Environmental Gradient

Abstract: In the past two decades, forest management has undergone major paradigm shifts that are challenging the current forest modelling architecture. New silvicultural systems, guidelines for natural disturbance emulation, a desire to enhance structural complexity, major advances in successional theory, and climate change have all highlighted the limitations of current empirical models in covering this range of conditions. Mechanistic models, which focus on modelling underlying ecological processes rather than specific forest conditions, have the potential to meet these new paradigm shifts in a consistent framework, thereby streamlining the planning process. Here we use the NEBIE (a silvicultural intervention scale that classifies management intensities as natural, extensive, basic, intensive, and elite) plot network, from across Ontario, Canada, to examine the applicability of a mechanistic model, ZELIG-CFS (a version of the ZELIG tree growth model developed by the Canadian Forest Service), to simulate yields and species compositions. As silvicultural intensity increased, overall yield generally increased. Species compositions met the desired outcomes when specific silvicultural treatments were implemented and otherwise generally moved from more shade-intolerant to more shade-tolerant species through time. Our results indicated that a mechanistic model can simulate complex stands across a range of forest types and silvicultural systems while accounting for climate change. Finally, we highlight the need to improve the modelling of regeneration processes in ZELIG-CFS to better represent regeneration dynamics in plantations. While fine-tuning is needed, mechanistic models present an option to incorporate adaptive complexity into modelling forest management outcomes.

Trade-Offs among Release Treatments in Jack Pine Plantations: Twenty-Five Year Responses

Abstract: We assessed 27 indicators of plant diversity, stand yield and individual crop tree responses 25 years post-treatment to determine long-term trade-offs among conifer release treatments in boreal and sub-boreal forests. This research addresses the lack of longer-term data needed by forest managers to implement more integrated vegetation management programs, supporting more informed decisions about release treatment choice. Four treatments (untreated control, motor-manual brushsaw, single aerial spray, and complete competition removal) were established at two jack pine (Pinus banksiana Lamb.) sites in Ontario, Canada. Our results suggest that plant diversity and productivity in boreal jack pine forests are significantly influenced by vegetation management treatments. Overall, release treatments did not cause a loss of diversity but benefitted stand-scale yield and individual crop tree growth, with maximum benefits occurring in more intensive release treatments. However, none of the treatments maximized all 27 indicators studied; thus, forest managers are faced with trade-offs when choosing treatments. Research on longer term effects, ideally through at least one rotation, is essential to fully understand outcomes of different vegetation management on forest diversity, stand yield, and individual crop tree responses.

Changes of tree stem biomass in European forests since 1950

Abstract: Based on the measurements of the biomass of the stems of 3 699 trees of Scots pine, Norway spruce, and silver birch in Europe since 1950, it has been shown that these tree species show a reduction in biomass and wood density. These results contradict the fact that the volume of wood is directly converted to biomass using the historical values of the conversion rates. From 1950 to 2020 the biomass of 1 m3 of the stem with bark decreased on average by 80 kg (–17%) for Scots pine, by 105 kg (–22%) for Norway spruce and by 92 kg (–15%) for silver birch. The results obtained should be taken into account when assessing the technical properties of wood and estimating carbon sequestration by forest biomass. Since decreasing trends in stem biomass have been identified for several tree species, the phenomenon may have a large degree of generality. Such studies should be continued both at the regional and national level and at the global level.

Simulation Models of the Dynamics of Forest Ecosystems

Abstract: The development of simulation models of the dynamics of forest ecosystems has been an active area of research [...]

Vegetation management is essential to regeneration success of red oak (Quercus rubra L.) at its northern range limit: results from a 10-year field experiment

Abstract: The effect of three vegetation management treatments on height, root collar diameter, mortality probability, health, and dominance class were assessed for planted and natural red oak (Quercus rubra L.) regeneration over a ten-year period in a red oak stand in Phelps Township, Ontario. Oak was planted in equally spaced positions in rows or in clusters of three seedlings. One of three vegetation management treatments was applied to both herbaceous and woody competitors within a 2-metre radius: untreated control, brush saw, and herbicide application. Oaks that received vegetation management were significantly taller, had larger root collar diameters, were in better condition, and were more dominant than in untreated control plots, and treatment differences increased with time. We found naturally regenerated oaks were taller and had larger root collar diameters followed by those planted in clusters, with oaks planted in rows being the smallest overall. Our results underscore the need to apply vegetation management around oak regeneration to control competition and promote establishment regardless of whether regeneration is natural or planted. In stands where natural regeneration is not an option and lower future oak stocking is acceptable, managers should consider cluster planting over row planting.

Simulation model in determining forestry and plantation circumstances

Abstract: Plantation and forestry systems consist of several dynamic subsystems as well as complexes that are integrated. Plantation and forestry productivity is largely determined by the interactions of each of these sub-systems. Simulation models can illustrate interactions between sub-systems in detail to be analyzed and evaluated in predicting any conditions that may occur. The model is indispensable because it leads to significant savings in time and money. This article is compiled by selecting and analyzing the previous research methods selected to draw conclusions on interactions between sub-systems to achieve effective and efficient plantation productivity. The final results show that how sub-systems affect forestry and plantation productivity can be demonstrated by hybrid simulation models. Therefore, hybrid simulation methods can be used to determine the integration process of each party in affecting the productivity of plantations and forests. The hybrid simulation model incorporated in two distinct approaches, namely Agent Based Modeling and System Dynamics. The models of hybrid simulation are useful as an illustration of interactions between each sub-system taking into account influential input variables.