Suchergebnisse

This paper highlights the importance of product differentiation and endogenous R&D in determining the optimal R&D policy, in a model where investment in cost reducing R&D is committed before firms compete in a differentiated-goods third-country export market. R&D is always taxed in oligopolies for high degrees of product differentiation. For lower degrees of product differentiation the duopoly is subsidized or the government remains inactive. In contrast, the monopoly is always subsidized. The government with a duopoly may be active or inactive depending on the degree of product differentiation. Thus, we may observe a reversal in the sign of the optimal R&D policy if the degree of product differentiation changes or, alternatively, if there is a change in the number of firms. Similar qualitative results hold if trade policy uses output subsidies, instead of R&D promotion.

Abstract
We analyze how the cost-effectiveness of R&D influences the incentives for governments to impose export subsidies. Governments first impose an export subsidy, or a tax. After observing export policy, firms invest in cost reducing R&D and subsequently compete in the market. Governments subsidize exports under Cournot competition. Under Bertrand competition and for linear demands and constant marginal costs, export subsidies are positive whenever R&D is sufficiently cost-effective at reducing marginal costs, and negative otherwise. The trade policy reversal found in models without endogenous sunk costs disappears if R&D is sufficiently cost-effective. Thus, output subsidies seem more robust than implied by the recent literature.

This paper analyzes the incentives for governments to impose export subsidies when firms invest in a cost saving technology before market competition. Governments first impose an export subsidy or a tax. After observing export policy, firms invest in cost reducing R&D and subsequently compete in the market. Governments subsidize exports under Cournot competition. Under Bertrand competition, export subsidies are positive whenever R&D is sufficiently cost-effective at reducing marginal costs, and negative otherwise. The trade policy reversal found in models without endogenous sunk costs disappears if R&D is sufficiently cost-effective. Thus, output subsidies seem more robust than implied by the recent literature.

We analyze how the cost-effectiveness of R&D influences the incentives for governments to impose export subsidies. Governments first impose an export subsidy, or a tax. After observing export policy, firms invest in cost reducing R&D and subsequently compete in the market. Governments subsidize exports under Cournot competition. Under Bertrand competition and for linear demands and constant marginal costs, export subsidies are positive whenever R&D is sufficiently cost-effective at reducing marginal costs, and negative otherwise. The trade policy reversal found in models without endogenous sunk costs disappears if R&D is sufficiently cost-effective. Thus, output subsidies seem more robust than implied by the recent literature. ; We acknowledge support from Comunidad de Madrid under grant 06/0064/00 and Ministerio de Ciencia y Tecnología under grant BEC2002-03715. We thank Peter Neary and participants of the ETSG and EARIE conferences for comments on an earlier draft and an anonymous referee for useful suggestions. The opinions and analyses herein are the responsibility of the authors and, therefore, do not necessarily coincide with those of the Banco de España or the Eurosystem. ; Publicado

Invasive species pose a major threat to global diversity, and once they are well established their eradication typically becomes unfeasible. However, certain natural mechanisms can increase the resistance of native communities to invaders and can be used to guide effective management policies. Both competition and herbivory have been identified as potential biotic resistance mechanisms that can limit plant invasiveness, but it is still under debate to what extent they might be effective against well-established invaders. Surprisingly, whereas biotic mechanisms are known to interact strongly, most studies to date have examined single biotic mechanisms separately, which likely influences our understanding of the strength and effectiveness of biotic resistance against invaders. Here we use long-term field data, benthic assemblage sampling, and exclusion experiments to assess the effect of native assemblage complexity and herbivory on the invasion dynamics of a successful invasive species, the alga Caulerpa cylindracea. A higher complexity of the native algal assemblage limited C. cylindracea invasion, probably through competition by canopy-forming and erect algae. Additionally, high herbivory pressure by the fish Sarpa salpa reduced C. cylindracea abundance by more than four times. However, long-term data of the invasion reflects that biotic resistance strength can vary across the invasion process and it is only where high assemblage complexity is concomitant with high herbivory pressure, that the most significant limitation is observed (synergistic effect). Overall, the findings reported in this study highlight that neglecting the interactions between biotic mechanisms during invasive processes and restricting the studied time scales may lead to underestimations of the true capacity of native assemblages to develop resistance to invaders ; Funding for this project was obtained from the Spanish Ministry Project ANIMA (CGL2016-76341-R, MINECO/FEDER, UE), the European Union's EMFS Program, AFRIMED ...

Seagrass meadows, key ecosystems supporting fisheries, carbon sequestration and coastal protection, are globally threatened. In Europe, loss and recovery of seagrasses are reported, but the changes in extent and density at the continental scale remain unclear. Here we collate assessments of changes from 1869 to 2016 and show that 1/3 of European seagrass area was lost due to disease, deteriorated water quality, and coastal development, with losses peaking in the 1970s and 1980s. Since then, loss rates slowed down for most of the species and fast-growing species recovered in some locations, making the net rate of change in seagrass area experience a reversal in the 2000s, while density metrics improved or remained stable in most sites. Our results demonstrate that decline is not the generalised state among seagrasses nowadays in Europe, in contrast with global assessments, and that deceleration and reversal of declining trends is possible, expectingly bringing back the services they provide. ; This research was supported by the COST Action ES0906. C.B.d.l.S. acknowledges the support by the Short-Term Scientific Missions (COST-STSM-ES0906-06377, -06441 and -06419) and the Portuguese Foundation for Science and Technology (FCT) fellowship (SFRH/BPD/119344/2016). C.B.d.l.S. and R.S. acknowledge the support of FCT through project UID/Multi/04326/2019. D.K-J. was supported by the European Union (WISER 226273), the Danish Strategic Science Foundation (NOVAGRASS, 0603-00003DSF), and the Ministry of Environment and Food of Denmark (33010-NIFA-16-651). N.M. was supported by Spanish Ministry of Economy, Industry and Competitiveness (MedShift, CGL2015-71809-P), by the European Union (M&M's, EVK3-CT-2000–00044 and WISER 226273), by the Fundación BBVA (Proyecto Praderas), and the Spanish Government (MEDEIG. CTM2009–07013). King Abdullah University of Science and Technology (KAUST) supported C.M.D. through baseline funding. J.M.R. acknowledges the project Monitoring network of Posidonia oceanica meadows and global climate change of the Murcia Region funded by the Autonomous Government of the Murcia Region (General Directorate of Livestock and Fishery), the European Fishery Fund (EFF 2007–2013), and European Maritime and Fisheries Fund (EMFF 2014–2020), and the Spanish Ministry of Industry, Economy and Competitiveness (UMBRAL, CTM2017-86695-C3-2-R).

Seagrass meadows, key ecosystems supporting fisheries, carbon sequestration and coastal protection, are globally threatened. In Europe, loss and recovery of seagrasses are reported, but the changes in extent and density at the continental scale remain unclear. Here we collate assessments of changes from 1869 to 2016 and show that 1/3 of European seagrass area was lost due to disease, deteriorated water quality, and coastal development, with losses peaking in the 1970s and 1980s. Since then, loss rates slowed down for most of the species and fast-growing species recovered in some locations, making the net rate of change in seagrass area experience a reversal in the 2000s, while density metrics improved or remained stable in most sites. Our results demonstrate that decline is not the generalised state among seagrasses nowadays in Europe, in contrast with global assessments, and that deceleration and reversal of declining trends is possible, expectingly bringing back the services they provide. ; COST Action - ES0906; Portuguese Foundation for Science and Technology (FCT) fellowship - SFRH/BPD/119344/2016; FCT - UID/Multi/04326/2019; European Union -06441C EVK3-CT-2000-00044 WISER 226273; Danish Strategic Science Foundation (NOVAGRASS) - 0603-00003DSF; Ministry of Environment and Food of Denmark - 33010-NIFA-16-651; Spanish Ministry of Economy, Industry and Competitiveness (MedShift) - CGL2015-71809-P; Fundacion BBVA (Proyecto Praderas); Spanish Government - MEDEIG. CTM2009-07013; King Abdullah University of Science and Technology (KAUST); European Fishery Fund (EFF 2007-2013); European Maritime and Fisheries Fund (EMFF 2014-2020); Spanish Ministry of Industry, Economy and Competitiveness (UMBRAL) - CTM2017-86695-C3-2-R; Autonomous Government of the Murcia Region (General Directorate of Livestock and Fishery); Short-Term Scientific Missions - COST-STSM-ES0906-06377; COST-STSM-ES0906-06441; COST-STSM-ES0906-06419; ; info:eu-repo/semantics/publishedVersion

Seagrass meadows, key ecosystems supporting fisheries, carbon sequestration and coastal protection, are globally threatened. In Europe, loss and recovery of seagrasses are reported, but the changes in extent and density at the continental scale remain unclear. Here we collate assessments of changes from 1869 to 2016 and show that 1/3 of European seagrass area was lost due to disease, deteriorated water quality, and coastal development, with losses peaking in the 1970s and 1980s. Since then, loss rates slowed down for most of the species and fast-growing species recovered in some locations, making the net rate of change in seagrass area experience a reversal in the 2000s, while density metrics improved or remained stable in most sites. Our results demonstrate that decline is not the generalised state among seagrasses nowadays in Europe, in contrast with global assessments, and that deceleration and reversal of declining trends is possible, expectingly bringing back the services they provide. ; This research was supported by the COST Action ES0906. C.B.d.l.S. acknowledges the support by the Short-Term Scientific Missions (COST-STSM-ES0906-06377, -06441 and -06419) and the Portuguese Foundation for Science and Technology (FCT) fellowship (SFRH/BPD/119344/2016). C.B.d.l.S. and R.S. acknowledge the support of FCT through project UID/Multi/04326/2019. D.K-J. was supported by the European Union (WISER 226273), the Danish Strategic Science Foundation (NOVAGRASS, 0603-00003DSF), and the Ministry of Environment and Food of Denmark (33010-NIFA-16-651). N.M. was supported by Spanish Ministry of Economy, Industry and Competitiveness (MedShift, CGL2015-71809-P), by the European Union (M&M's, EVK3-CT-2000–00044 and WISER 226273), by the Fundación BBVA (Proyecto Praderas), and the Spanish Government (MEDEIG. CTM2009–07013). King Abdullah University of Science and Technology (KAUST) supported C.M.D. through baseline funding. J.M.R. acknowledges the project Monitoring network of Posidonia oceanica meadows and global climate ...