Biodiversity

Biodiversity Sector

Purpose and Perspective

The Biodiversity sector represents the major factors affecting biodiversity change, and determines based on those the GEF benefits index for biodiversity. Factors affecting biodiversity include changes in precipitation and temperature, deforestation, and nitrogen emissions through gasseous losses and nitrous oxide emissions. The sector also calculates the proportion of marine areas protected – a key factor to preserve marine biodiversity – as a function of the public and private investment for marine areas protection. Finally, the sector includes the calculation of available fish resources, based on fish capture and an estimation of sustainable fish capture (based on long-term trend for fish stocks).

Model Structure and Major Assumptions

  • Changes in precipitation and temperature, deforestation, and nitrogen emissions through gasseous losses and nitrous oxide emissions are the major factors affecting biodiversity [1]

  • There are no interactions among the various causes of biodiversity change [2]

  • Effects of the various causes of biodiversity change are represented via a power function [3]

  • Estimation of the intensity of the effect of the various causes of biodiversity change is based on Rosenzweig (1995) [4]

  • Marine areas protection unit cost are estimated based on Balmford et al (2004) and McCrea-Strub et al (2011) [5]

  • For the estimation of fish resources availability and long-term sustainable capture we use data from the Seaaroundus database

Exogenous Input Variables

None

Initialization Variables

  • Initial GEF benefits index for biodiversity - Units: Dmnl

Modeling Details

Less relevant causes of biodiversity change include biotic exchange and atmospheric CO2 concentration (Sala et al. 2000) [6]. The formulation adopted to determine change in biodiversity is flexible so as to allow for the inclusion of such drivers should they be relevant in specific countries.

Footnotes and References

[1] Sala, O.E., Chapin, F.S., Armesto, J.J., Berlow, E., Bloomfield, J., Dirzo, R., et al (2000). Global Biodiversity Scenarios for the Year 2100. Science 287,(1770).

[2] Sala, O.E., Chapin, F.S., Armesto, J.J., Berlow, E., Bloomfield, J., Dirzo, R., et al (2000). Global Biodiversity Scenarios for the Year 2100. Science 287,(1770).

[3] Preston, F.W. (1962). The Canonical Distribution of Commonness and Rarity: Part I. Ecology, 43,(2): 185-215.

[4] Rosenzweig, M. (1995). Species diversity in space and time. Cambridge, UK: Cambridge University Press.

[5] Balmford, A., Gravestock, P., Hockley, N., McClean, C.J., & Roberts, C.M. (2004). The worldwide costs of marine protected areas. Proceedings of the Naitonal Academy of Sciences.

McCrea-Strub, A., Zeller, D., Sumaila, U.R., Nelson, J., Balmford, A. & Pauly, D. (2011). Understanding the cost of establishing marine protected areas. Marine Policy 35: 1–9.

[6] Pauly, D. & Zeller, D. (2015). So long, and thanks for all the fish: The Sea Around Us, 1999-2014, A fifteen year retrospective. Vancouver, BC: Sea Around Us, Fisheries Centre, The University of British Columbia, Vancouver. Data available from seaaroundus.org