Difference between revisions of "MELA"

Revision as of 13:41, 30 September 2009

General System description

System name: MELA

Mela is Finnish for "Steering paddle of a rowing boat" (NABUURS et PÄIVINEN 1996)

Brief overview

MELA is an operational decision support system developed and maintained by Metla (Finnish Forest Research Institute) based on its forest research.

This system has been used since the 1980s in the analyses of wood production possibilities and the impact of different harvest levels at national and regional scale in Finnland^[1].

Scope of the system

MELA is a general analysis tool for forest management planning. It can be used e.g. in the computational updating of forest resource data and in the search of effective or optimal production programs for forest areas (a property or a company). When linked with end-user applications for forest planning, the MELA software supports interactive planning. For example, the current MELA version provides more diversified and detailed information for taking into account errors and risk. Furthermore, MELA allows flexible combinations of various data sources and models to improve cost-efficiency and effectiveness of forest inventory and planning.

MELA consists of two separate programs communicating with each others via MELA system files:

1. MELASIM, an automated stand simulator based on individual trees.
2. MELAOPT, the optimisation package based on the linear programming package, JLP.

System origin

• MELA is developed by the MELA Team, that belongs to METLA (The Finnish Forest Research Institute).
• The most recent version of MELA is MELA2007, released in December 2007. The first MELA version dates from 1983. Since then, eight improved versions have been launched (MELA96, MELA98, MELA99, MELA2000, MELA2002, MELA2004, MELA2005 and MELA2007)
• MELA system has been installed by a number of clients in state, company and private forestry since its first release in the 1980s.

Support for specific issues

The MELA model provides for a large number of control variables (manipulation possibilities) of biological and economic nature^[2].

Related systems

• DemoMELA
• NettiMELA
• GAYA-JLP

Data and data models

Typical spatial extent of application

Although being extensively used in national and regional planning, MELA is not only used at this scale scenarios, but also in ownership planning.

Forest data input

The main simulation variables for trees in the current simulator version are number of stems/ha (that each tree represents), tree species, diameter, height and age. Simulation instructions and some obligatory system files must also be provided in the MELASIM input files.

The input for MELAOPT consists of materials such as initial forest resource data, management schedule data, optimisation problem definitions and some obligatory system files.

Forest resources and running information data is supplied as MELA data files. Any kind of user-supplied initial data files have to be compatible with the MELA software. MELA extensions for updating and for the conversion of initial data and stand simulation instructions are available for the interface development.

The following tree species are available:

• Scotch pine (Pinus sylvestris)
• Norway spruce (Picea abies)
• Silver birch (Betula pendula)
• Downy birch (Betula pubescens)
• Aspen (Populus tremula)
• Alder (Alnus incana, Alnus glutinosa)
• Other coniferous species
• Other deciduous species

Models

Forest models

MELA simulates a finite number of feasible and alternative management schedules (options) for the management units over the chosen calculation period automatically according to the given simulation instructions. Management schedules differ from each other, for example, in timing of management activities. After simulation MELA can be used to select from these options simultaneously both a production programme for the whole forest area and corresponding management schedules for the individual management units according to the optimisation problem (goals and restrictions) defined by the user.

Decision Support

Definition of management interventions

In MELA, the management of forests is endogenous, i.e. the decision when and how to cut an individual management unit is based on the user-defined goals and restrictions concerning the production or status of the whole forest area and domains in question over the planning period. The growth, felling regimes and the development of growing stock are the results of the analysis.

Typical temporal scale of application

MELA is typically used for strategic planning. However, longer calculation periods than 50 years should not be used due to current models of natural processes according to the authors (NABUURS et PÄIVINEN 1996).

Decision-making processes and models

• Linear programming

Output

Types of outputs

The current MELA provides results both in the form of table type reports directly for users and in the form of files for further processing by user programs or commercial software for creating tables, graphics, maps, etc.

The information provided by the output files differs from the MELASIM and the MELAOPT modules. MELASIM output information will be management schedule data and forest level summary reports ready to be used by MELAOPT. On the other hand, MELAOPT output information may be forest level solution reports, management schedule (stand level solution) reports, shadow price reports, cost of change reports, or forest level summary data for further processing.

Spatial analysis capabilities

No adjacency constraints can be specified. Instead, constrains can be provided for any (overlapping) set of management units.

There is a moderate GIS connection. Results can be presented on large-scale maps.

System

System requirements

MELA software is currently available in Windows NT, Windows 2000, Windows XP and Windows Vista operating systems. Other operating systems suitability should be studied case by case.

Architecture and major DSS components

It was programmed in FORTRAN, it is portable to DOS, Windows, OS/2, VMS, and several UNIX environments.

The two principal components of the MELA software are the MELASIM and the MELAOPT modules. Other extensions area also available.

Usage

The MELA software can be used as a forest management planning module of stand information systems in state, private and industrial forestry.

Computational limitations

The capacity of MELASIM and MELAOPT depends on the program version being used.

User interface

The MELA programs have a command line user interface. Command lines are related and explained in the reference manual.

MELA can be characterised as not user-friendly at present. A wide range of capabilities and expertise is required by the user.

Documentation and support

A very extensive and complete reference manual has been published. It is free to download together with previous versions of MELA manuals in the MELA website. A telephone answering and advising service is also available.

Installation

• Demo: A demo version ready to free online use previous registration is offered under the DemoMELA.

References

Cited references

1. ↑ GADOW, K.v., T. NUUTINEN et S. KELLOMÄKI (2008): Adaptative Design of Forested Landscapes. In GADOW, K.v. et T. PUKKALA (Eds.): Designing Green Landscapes. Springer, New York, pp 3-30.
2. ↑ EID, T. et K. HOBBELSTAD (2000): AVVIRK-2000: A Large-scale Forestry Scenario Model for Long-term Investment, Income and Harvest Analyses ‘’Scand. J. For. Res.’’ 15: 472-482.

External resources

• MELA website (in Finnish)
• REDSVEN, V., H. HIRVELÄ, K. HÄRKÖNEN, O. SALMINEN et M. SIITONEN (2007): ‘’MELA2007 Reference Manual’’. Metsäntutkimuslaitos - The Finnish Forest Research Institute. 642 p.
• NABUURS G.J. et R. PÄIVINEN (1996): Large Scale Forestry Scenario Models - a compilation and review. European Forest Institute Working Paper No. 10. Joensuu, Finland.