Browsing Miscellaneous themes by Author "Christensen, V."

Now showing items 1-17 of 17

    • A draft guide to the ECOPATH II program (ver. 1.0) 

      Christensen, V.; Pauly, D. (1990)
      Type: Manual
      This guide documents the use and background of a program written for MSDOS Computers, in QUICKBASIC 4.5, for straightforward construction and parametrization of steady-state trophic models of aquatic ecosystems. The ECOPATH ...

    • A guide to ECOPATH II software system (version 2.0) 

      Christensen, V.; Pauly, D. (1991)
      Type: Manual
      This guide documents the use and background of the ECOPATH II software system written for MS DOS computers for straightforward construction and parametrization of steady-state trophic models of aquatic ecosystems. ECOPATH ...

    • A guide to the ECOPATH II software system (version 2.1) 

      Christensen, V.; Pauly, D. (1992)
      Type: Manual
      The software described in the present guide is designed to help user construct a simple model of an aquatic ecosystem.

    • A trophic ecosystem model of Lake George, Uganda 

      Moreau, J.; Christensen, V.; Pauly, D. (1993)
      Type: Book Chapter
      A trophic model of Lake George, Uganda, Central Africa was constructed using published quantitative and qualitative information on the various biotic components of the lake and the ECOPATH II approach and software. It is ...

    • Changes in models of aquatic ecosystems approaching carrying capacity 

      Christensen, V.; Pauly, D. (1998)
      Type: Journal Article
      Using a top-down modeling approach, published mass-balance models of trophic interactions and state variables in the western central Pacific Ocean and the northern Gulf of Mexico shelf were used to explore how large increases ...

    • Diet composition and trophic levels of marine mammals 

      Pauly, D.; Trites, A.W.; Capuli, E.; Christensen, V. (1998)
      Type: Journal Article
      Standardized diet compositions were derived for 97 species of marine mammals from published accounts of stomach contents as well as from morphological, behavioural and other information. Diet was apportioned among eight ...

    • Ecosystem maturity: towards quantification 

      Christensen, V. (1995)
      Type: Journal Article
      An attempt is made to rank 41 steady-state models of aquatic ecosystems on the basis of their maturity. Maturity is quantified using several of Odum's attributes of ecosystem maturity. It is shown that it is possible to ...

    • Emergy-based ascendency 

      Christensen, V. (1994)
      Type: Journal Article
      Ascendency is a system indicator used for describing flow characteristics of ecosystems. Experience shows, however, that ascendency is primarily a function of the flow characteristics at the lowest trophic levels. This is ...

    • Flow characteristics of aquatic ecosystems 

      Christensen, V.; Pauly, D. (1993)
      Type: Book Chapter
      This contribution examines various flow measures based on analysis of 41 quantified models of trophic interactions in aquatic ecosystems.

    • Flow modelling with ECOPATH: providing insights on the ecological state of agroecosystems 

      Dalsgaard, J.P.T.; Christensen, V. (1997)
      Type: Book Chapter
      This paper summarizes the major findings in modelling and analysing agroecosystems using ECOPATH.

    • Guide du logiciel ECOPATH II (version 2.1) 

      Christensen, V.; Pauly, D. (1992)
      Type: Manual
      This guide documents the use and background of the ECOPATH II software system written for MS DOS computers for straightforward construction and parametrization of steady-state trophic models of aquatic ecosystems. ECOPATH ...

    • On ECOPATH, Fishbyte and fisheries management 

      Christensen, V. (1991)
      Type: Journal Article
      A brief account of the origin and basic assumptions of the ECOPATH software and approach is given, with emphasison their documentation in Fishbyte, and to the transition to its successor, the ECOPATH II program. Some ...

    • On the behavior of some proposed goal functions for ecosystem development 

      Christensen, V. (1994)
      Type: Journal Article
      This contribution addresses the issue of "goal functions", quantifying the state of development of ecosystems. Numerous goal functions have been proposed with the hope that once a proper goal function has been identified ...

    • Structuring dynamic models of exploited ecosystems from trophic mass-balance assessment 

      Walters, C.; Christensen, V.; Pauly, D. (1997)
      Type: Journal Article
      The linear equations that describe trophic fluxes in mass-balance, equilibrium assessments of ecosystems (such as in the ECOPATH approach) can be re-expressed as differential equations defining trophic interactions as ...

    • The ECOPATH II software or how we can gain from working together 

      Christensen, V. (1990)
      Type: Journal Article
      Problems involved in the development of ecosystem models are discussed, considering in particular the use of the ECOPATH II software and the approach used at ICLARM in the project "Global comparisons of trophic aquatic ...

    • Towards quantification of ecological sustainability in farming systems analysis 

      Dalsgaard, J.P.T.; Lightfoot, C.; Christensen, V. (1993)
      Type: Journal Article
      A tentative list of ecological attributes; diversity, cycling, stability and capacity, is proposed for quantification and ranking of farming systems along a hypothetical scale of increasing ecological sustainability. The ...

    • Trophic models of aquatic ecosystems 

      Christensen, V.; Pauly, D. (eds.) (1993)
      Type: Conference Proceedings
      A large proportion of the contributions to the ICES Theme Session on "Trophic models in aquatic ecosystems" is presented, together with papers of a number of scientists and very experienced ecosystem modellers.