1. General Model Information
Name: Pinus sylvestris: Nutrient cycling model
Acronym: PINEL
Main medium: terrestrial
Main subject: biogeochemistry, forestry
Organization level: Population
Type of model: ordinary differential equations, static-algebraic equations,
Main application: research, decision support/expert system, simulation/optimisation tool
Keywords: Pinus sylvestris, Spain, Whole-tree removal, Thinning, Forest harvesting, Nitrogen, Phosphorus, Mediterranean pine forest, sustainable forest management
Contact:
Dr. Federico J. Castillo
Departamento de Ciencias del Medio Natural, Edificio los Olivos, Universidad Publica de Navarra,
E-31006 Pamplona, Navarra,
Spain
Phone: 34 948 169 115
Fax: 34 948 168 930
email: federico.castillo@unavarra.es
Author(s):
J.A. Blanco, M.A. Zavala, J. B. Imbert, F.J. Castillo
Abstract:
Forest harvesting may interfere with long-term ecosystem structure and function and different harvesting methods will differ
in their effects on soil fertility (e.g. whole-tree harvesting versus stem removal). In the case of thinning, effects of thinning
intensity, rotation length and site quality must be assessed in order to formulate sustainable management practices. Assessment
of the relative impact of these practices is difficult, however, given the long temporal scales involved. In this study, we implement
a process-based model of nutrient cycling to evaluate temporal changes in ecosystem nutrient dynamics of managed and nonmanaged
forest stands. The model was specifically designed to asses differences between two contrasting site-quality Pinus
sylvestris L. stands in the western Pyrenees (Navarre, Spain) managed under two thinning intensities. The model describes the
main nutrient fluxes in the stand: litterfall, decomposition, retranslocation, root uptake and management type, and it was
parameterized and verified with 3 years of field data. After model verification we examined the effects of thinning intensity,
thinning frequency and harvesting method (whole-tree versus stem removal) on potential nutrient losses. The results suggest that
in this heterogeneous region, sustainability of forestry practices is strongly site dependent. N and P were particularly sensitive to
overexploitation and in no case could whole-tree removal be recommended as it may have a strong negative effect on nutrient
reserves. In relation to previous nutrient cycling models, our model offers a satisfactory compromise between simplicity,
biological realism and predictability, and it proved to be a useful tool to predict short-term changes in nutrient reserves as well as
to evaluate possible negative effects of applying current thinning prescriptions on long-term sustainability of managed forests in
the western Pyrenees.
II. Technical Information
II.1 Executables:
Operating System(s): STELLA Research
II.2 Source-code:
Programming Language(s): STELLA Research
II.3 Manuals:
II.4 Data:
III. Mathematical Information
III.1 Mathematics
III.2 Quantities
III.2.1 Input
Nutrient concentrations in Pinus sylvestris tissues Nutrient concentrations in Pinus sylvestris litterfall Decomposition rates Type of thinning (stem-only or whole-tree, stand age for the first thinning, %Basal area removed)
III.2.2 Output
Accumulated nutrient losses in one rotation
IV. References
Juan A. Blanco, Miguel A. Zavala, J. Bosco Imbert and Federico J. Castillo. 2005. Sustainability of forest management practices: Evaluation through a simulation model of nutrient cycling. Forest Ecology and Management 213(1-3), 209-228
V. Further information in the World-Wide-Web
VI. Additional remarks
Last review of this document by: : Wed Apr 5 00:58:31 2006
Status of the document: Contributed by Juan A. Blanco
last modified by
Joachim Benz Tue May 9 16:22:26 CEST 2006