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This paper attempts to develop a dynamic model of optimal biodiversity preservation in a stylized ecosystem. Species richness (number of species) is used as a measure of diversity and its interactions with the resource stock, consumptive extraction and preservation efforts are explored using a two-state variable optimal control model. The analysis extends to the implications of a random threshold in species richness and the relationship between ecological and economic stability conditions. Dynamic paths and equilibrium characteristics are illustrated using numerical techniques.

AbstractWe study the decision to preserve diverse species when the value of biodiversity is uncertain, or even affected by ambiguity. Optimal decisions are derived both from the perspective of the producer/investor and the policy regulator (ecosystem planner). We find that while calculated risk creates a scope for biodiversity preservation, the presence of ambiguity aversion reduces it, thus accelerating the extinction of species with lower value. Our results suggest that effective conservation strategies would involve a reduction of ambiguity aversion by creating a stable and transparent policy environment. Furthermore, they may involve a two tier strategy, with one tier addressing output targets and the other conservation targets.

Produce wood, preserve the environment, provide social services: all these goods and services are expected of the forests nowadays. Forests can sustainably produce them, but how much? These products are joined outputs in a production process composed of forest growth and management. Therefore, it is important to characterize how outputs are joined to set production goals. In this paper, we simulate alternative management scenarios for Quercus petraea even- aged high forest at the stand scale. Then we estimate for each scenario the production of three goods and services: 1) the production of wood in terms of the net present value of an infinite series of rotations (NPVIS); 2) the preservation of biodiversity, using an indicator of the number of bird species potentially present in the forest (Bio); 3) the production of a recreation service, in terms of attractiveness for recreational activities (A). Lastly, we determine production possibility frontiers for the three two-output combinations. We show that NPVIS and Bio or NPVIS and A are substitute products of forest management, but there are possibilities for producing both in the same forest. Bio and A are compatible to a certain extent. The methodology employed seems efficient to study multi-functionality at the stand level.

This article clarifies the potential environmental impacts of more or less expansive EU immigration policies. First, we project the demographic impacts of different immigration policy scenarios on future population numbers, finding that relatively small annual differences in immigration levels lead to large differences in future population numbers, both nationally and region-wide. Second, we analyze the potential impacts of future population numbers on two key environmental goals: reducing the EU's greenhouse gas emissions and preserving its biodiversity. We find that in both cases, smaller populations make success in these endeavors more likely – though only in conjunction with comprehensive policy changes which lock in the environmental benefits of smaller populations. Reducing immigration in order to stabilize or reduce populations thus can help EU nations create ecologically sustainable societies, while increasing immigration will tend to move them further away from this goal.

The Ecological Tax on the Circulation of Goods and Services for Biodiversity (ICMS-E) was created in 1991 as an initiative of the government of Paraná State. It is an important public policy instrument for the preservation of biodiversity in small municipalities that house Conservation Units. The aim of this article was to analyze whether resources from the ICMS-E, added to municipal tax revenues, improve sustainable development over time. As part of the methodological procedures, a descriptive-comparative analysis was conducted between municipalities that receive and do not receive ICMS-E. For this purpose, a sampling of the 399 municipalities that comprise Paraná State was conducted, involving 193 municipalities with a population of up to 50,000 inhabitants. The comparative analysis was based on the definition of two study groups, each constituted by 76 municipalities: one called the ICMS-E Recipient Group, municipalities that receive the ecological tax; and the Control Group, composed of those that do not receive it. The main results indicate that 19.80% of the municipalities are concentrated in the North Central mesoregion, while the Metropolitan Region of Curitiba is home to 33.45% of the population of Paraná. In relation to population loss, this factor represents 44.73% in the ICMS-E Recipient Group, while in the Control Group this number is 34.21%. In relation to the Environmental Management Function, 60.53% of the municipalities in the Recipient Group applied up to 75% of this tax to this function. It was concluded that the ICMS-E is an important incentive for the preservation of biodiversity and represents a significant increase in resources for the local governments of smallmunicipalities.

This paper reconsiders forest biodiversity valuation, and the extent to which information affects the value individuals attach to forest biodiversity attributes. A choice experiment design was applied to the survey protocol. A split-sample technique was then used out to obtain two datasets. The first dataset corresponds to the choices from individuals who responded to the neutral survey protocol. The second dataset was obtained from the same choice sets as for the neutral survey protocol, but the survey used also specific information to respondents on each biodiversity attribute. We then applied the latent class approach to ascertain preference heterogeneity according to respondents' environmental knowledge and sensitiveness to issues of biodiversity. We found that willingness to pay (WTP) values were higher for 'familiar' respondents, i.e., those who make regular use of forests and are more sensitive to biodiversity concerns, as opposed to 'unfamiliar' participants. For the former, giving more information had an influence on choices. For the latter, giving more information increased WTP for preferred biodiversity attribute levels. We then concluded that giving specific information on biodiversity to the public does affect preferences. However, environmental sensitiveness combined with forest use constitutes the main explanatory variables of higher WTP. Adapted from the source document.

Using grounded theory development research methods, the authors examine collaborative processes in the global biodiversity preservation domain. The processes examined are those initiated and convened by a subgroup of the Swiss-based International Union for the Conservation of Nature known as the Conservation Breeding Specialist Group of the Species Survival Commission. The global collaborative initiatives of the group suggest that extant theory on collaboration may not adequately explain collaborative processes in so complex a domain as global biodiversity preservation. Specifically, the authors suggest that in highly complex domains, effective structuring of collaborative initiatives may take different forms. Propositions about structuring of collaborations in complex domains are derived.

Cet article analyse l'impact de l'information fournie aux individus sur la valeur qu'ils accordent aux attributs de la biodiversité forestière. La méthode des expériences de choix a été appliquée, sur deux sous-échantillons afin d'obtenir deux ensembles de données : le premier correspondant à des choix obtenus avec un protocole d'enquête neutre, et le second à l'issue d'un protocole délivrant aux répondants des informations spécifiques sur chaque attribut de la biodiversité. L'estimation économétrique des préférences par le modèle de choix discrets à classes latentes permet de distinguer les valeurs du consentement à payer (CAP) des individus « familiers », c'est à dire ceux qui font un usage régulier des forêts et qui sont plus sensibles aux enjeux de préservation de la biodiversité, de celles des répondants « non familiers ». L'étude conclut que donner des informations spécifiques sur chacune des composantes de la biodiversité affecte les préférences du public. Cependant, la sensibilité à la cause environnementale et la connaissance de la forêt à partir de ses usages constituent les principales variables explicatives d'un CAP plus élevé.