Alexey Mikhailov

EFIMOD 2: a model of growth and cycling of elements in boreal forest ecosystems

Abstract The model EFIMOD 2 was developed for the description of tree (stand) growth and biological turnover of elements in boreal and temperate forest ecosystems. The model has the following features. (i) It is a spatially explicit stand-level simulator for Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies L. Karst) and Pendula birch (Betula pendula L.) on different forest soils growing under different climatic conditions in Europe; each stand consists of individual trees for which growth is modelled depending on the tree’s position within the stand and local light, water and available nutrient conditions. (ii) The model has a tree-based submodel for total biomass distributed between several biomass compartments. (iii) The calculations include natural regeneration as well as ground vegetation dynamics. (iv) The soil submodel (ROMUL) is used to assess organic matter dynamics and nitrogen availability for tree growth as a function of soil temperature, soil moisture content and litter quality. (v) EFIMOD 2 calculates nitrogen cycling and accounts for atmospheric nitrogen deposition, nitrogen fixation and leaching, vegetation uptake, litter fall and nitrogen redistribution within and between trees and soil horizons. (vi) Monte–Carlo simulations are done to simulate the extent of naturally oscillating variability. EFIMOD 2 allows for short-term and long-term simulations of natural and managed forest ecosystem dynamics over a wide range of forest sites, climatic conditions and silvicultural regimes. The model calculates dendrometric parameters for every tree, including undergrowth and seedlings, total growing stock, and pools of coarse woody debris and soil organic matter, with special reference to carbon and nitrogen dynamics. The model is effective for assessing wood productivity and evaluation of forest management regimes to meet criteria and indicators of Sustainable Forest Management. This includes a general evaluation of biodiversity and soil sustainability. The model system allows for the direct use of standard forest inventory data. Output variables include carbon and nitrogen pools in the stand and soil, CO2 emissions, and tree (stand) growth and yield.

Application of the forest ecosystem model EFIMOD 2 to jack pine along the Boreal Forest Transect Case Study

Sustainability of forest ecosystems and climate change are two critical issues for boreal forest ecosystems in Canada that require an understanding of the links and balance between productivity, soil processes and their interaction with natural and anth ropogenic disturbances. Forest ecosystem models can be used to understand and predict boreal forest ecosystem dynamics. EFIMOD 2 is an individual tree model of the forest-soil ecosystem capable of modelling nitrogen feedback to productivity in response to changes in soil moisture and temperature. It has been successfully applied in Europe, but has not been calibrated for any forest ecosystem in Canada. The objective of this study was to parameterize and validate EFIMOD 2 for jack pine in Canada. Simulated and measured results agreed for changes in tree biomass carbon and soil carbon and nitrogen with increasing stand age and across a climatic gradient from the southern to northern limits of the boreal forest. Preliminary results from scenario testing indic...

Analysis of the soil organic matter stability in spruce forests of Krkonose in Czechia on the basis of the ROMUL mathematical model

Computational experiments with the ROMUL mathematical model were performed for studying the dynamics of soil organic matter (SOM) in spruce forests of northeastern Czechia that were disturbed because of the atmospheric sulfur deposition in the second half of the 20th century. The effect of the soil acidification on the decomposition dynamics of the forest die-back in the model is of importance. Conditions of the forest productivity were found under which the SOM pool could be preserved. It was shown that, later on, the content of the litter will decrease because of the forest degradation, and the succession changes due to the effect of the contamination will affect the type of vegetation, as well as the type of soil organic matter. The total SOM content will decrease in this case. However, the maintenance of the grass productivity can slow down this process. It was noted that the quantitative prediction of the SOM dynamics requires measurements of the productivity parameters of the forest as a whole and the living ground cover, including the content of root litter, and the hydrothermal regime of the soil determining the transformation of the litter and humus.

20 - DLES: A Component-Based Framework for Ecological Modeling

Abstract Discrete Lattice Ecosystem Simulator (DLES) is a component-based framework which facilitates integration of stand-alone models with spatial interactions, and comparison between models. DLES allows coupling of models of different spatial and temporal resolution. The main features of our approach are (1) the system of models isn’t a “monolithic program” (single executable file), but a number of stand-alone modules that can be easily added to, and removed from, the system; (2) modules exchange data with each other via a shared area of memory controlled by a special system unit; and (3) a module can be either a submodel or another data provider (file, database, etc.).