Simulating the Potential Effects of a Changing Climate on Black Spruce and Jack Pine Plantation Productivity by Site Quality and Locale through Model Adaptation

Abstract

Abstract:Modifying the stand dynamic functional determinates of structural stand density management models (SSDMMs) through the incorporation of site-specific biophysical height-age equations enabled the simulation of the effects of increasing mean temperature and precipitation during the growing season on black spruce (Picea mariana (Mill.) BSP) and jack pine (Pinus banksiana Lamb.) plantation productivity. The analytical approach consisted of calculating future values of growing season mean temperature and precipitation rates under three emissions scenarios (no change (NC); B1; and A2), spanning three continuous commitment periods (2011-2040; 2041-2070; and 2071-2100), for three geographically separated sites throughout the central portion of the Canadian Boreal Forest Region (north-eastern (Kirkland Lake); north-central (Thunder Bay); and north-western (Dryden) Ontario, Canada), using the Canadian Coupled Global Climate Model (CGCM3) in conjunction with a geographic-referencing climatic surface model. These estimates were entered into the embedded biophysical equations in the SSDMMs in order to forecast emission-scenario-specific developmental patterns of plantations managed under a conventional density management regime by species and site quality (poor-to-medium and good-to-excellent) at each locale; from which stand development rates and associated productivity metrics over 75 year-long rotations were estimated and compared (e.g., mean sizes, volumetric, biomass and carbon yields, end-products, economic worth, stand stability, wood quality indices, and operability status). Simulation results indicated that black spruce plantations situated on both site qualities at the north-western location and on the lower site quality at the north-eastern location were negatively affected from the predicted increased warming and rainfall as evidenced from consequential declines in stand development rates and resultant decreases in rotational mean sizes, biomass yields, recoverable end-product volumes, and economic worth (A2 > B1). Conversely, black spruce plantations situated on both site qualities at the north-central location and on the higher site quality at the north-eastern location were minimally and positively affected under the A2 and B1 scenarios, respectively. Jack pine plantations situated on both site qualities at all three locations were negatively affected as evident by the reductions in stand development rates and rotational mean sizes, biomass yields, recoverable end-product volumes, and economic worth (A2 > B1). Collectively, these response patterns suggest that stand-level productivity under a changing climate will vary by species, site quality, geographic locale, and emission scenario, potentially resulting in a landscape-level mosaic of both negative and positive productivity impacts in the case of black spruce, and mostly negative impacts in the case of jack pine. As demonstrated, modelling stand-level responses to projected increases in thermal and moisture regimes through the modification of exis...

Ecological Management of Pine Forests

“…Despite the adequate fitting and the relevant contribution of this research, we speculate that these multifactorial models could get more resolution with dendroecological data using individual tree models based on other studies [40]. For a better estimate of radial growth, the model should be strengthened with other variables related to vegetation, such as competition indices, spatial distribution indices, trees quality and health [86][87][88][89][90][91][92]. These should be tracked in dynamics, which extends research over time.…”

Croplanner: A Stand Density Management Decision-Support Software Suite for Addressing Volumetric Yield, End-Product and Ecosystem Service Objectives When Managing Boreal Conifers

“…; [27]; henceforth denoted PNb N and PNb M , respectively) and black spruce (Picea mariana (Mill) BSP) stand-types; [30]; henceforth denoted PIm N and PIm M , respectively), upland natural-origin black spruce and jack pine mixtures ( [29]; henceforth denoted PImPNb N ), and lowland natural-origin black spruce stands ( [28]; henceforth denoted PIm LL-N ). Additionally, in order to account for changes in growing environments arising from anthropogenic climate change effects, climate-sensitive variants for the upland black spruce and jack pine natural-origin and plantation stand-types have also been developed (henceforth denoted PIm N(CC), PNb N(CC) , PIm M(CC) and PNb M(CC) , respectively; sensu [36]).…”

“…More specifically, based on yield-density relationships (e.g., reciprocal competition-density equation surrogate, self-thinning rule, relative density function), regime-specific temporal size-density trajectories are generated according to the specified site quality (site index), establishment density, genetic worth effect, type and intensity of thinning treatments, density-dependent mortality rate, density-independent mortality rate (operational adjustment factor), and climate change scenario. Genetic worth and thinning growth responses and climate change effects are all embedded within the sitespecific height-age models (e.g., [36,50,51], respectively). Collectively, this computational sequence yields an array of annual mean tree and stand level mensurational-based outcome metrics for each specified crop plan (regime).…”

“…Specifically, this was achieved through the development and subsequent integration of a set of optimization applications for automatically determining the optimal PCT, CT or IE+CT based density management regime according to the end-user-specified multivariate selection criteria and constraint set. Fourthly, as a prerequisite to algorithm formulation, the analytics of each SSDMD had to be successfully vetted and subsequently presented within the peer-reviewed scientific literature (e.g., [27][28][29][30][35][36][37]47,48,50,51,55,56,62,64]). Fifthly, all supporting material including publication reprints, numerical yield table output, graphical evaluation results and variable definition and interpretation guides, were to be explicitly included within the suite, graphical user interfaces would be self-explanatory via the use of supplemental on-screen cursor-activated textual descriptions, and program execution and operation would be intuitive and easily to comprehend by the targeted end-user community without the need for extensive training or referral inquires.…”

“…Currently, however, with respect to the dynamic SDMD and SSDMD variants developed for boreal stand-types in central Canada, only Fortran-based algorithmic analogues have been developed to date [27][28][29][30][32][33][34][35][36][37]. Although computationally efficient, the numeric and tabular reporting focus of these programs along with their lack of interactive graphical user interface (GUI) functionalities, has hinder their operational deployment.…”