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The ocean, which regulates climate and supports vital ecosystem services, is crucial to our Earth system and livelihoods. Yet, it is threatened by anthropogenic pressures and climate change. A healthy ocean that supports a sustainable ocean economy requires adequate financing vehicles that generate, invest, align, and account for financial capital to achieve sustained ocean health and governance. However, the current finance gap is large; we identify key barriers to financing a sustainable ocean economy and suggest how to mitigate them, to incentivize the kind of public and private investments needed for topnotch science and management in support of a sustainable ocean economy. The ocean supports many livelihoods, but this is currently not sustainable with pressures on the climate and ecosystems. Here, in this perspective, the authors outline the barriers and solutions for financing a sustainable ocean economy.

This paper addresses normative exploitation of common renewable resources with changes in technology and technical, allocative, and scale efficiency that exacerbate the commons problem and externality. Their impact depends on the rate and nature of change, investment, and state of property rights. An augmented fundamental equation of renewable resources with a modified marginal stock effect and a new marginal technology effect account for changes in disembodied and embodied technology and technical efficiency. Neglecting these changes generates misleading policy advice and dynamic inefficiency with overaccumulation of physical and natural capital and sizable foregone rents. An empirical application illustrates.

Food and feed production worldwide heavily relies on wheat (Triticum aestivum). However, current agricultural practices face numerous challenges including a shortage of land for cultivation, a desire to reduce the use of chemical pesticides and fertilizers, and the development of resistance towards employed pesticides and virulence towards host resistance in the most widely grown varieties. In this paper, we demonstrate based on the literature that cultivating wheat variety mixtures generally leads to increased yield and yield stability across years and environments, reduced severity of multiple diseases, and a decreased risk of lodging before harvest compared to the cultivation of pure stands. Moreover, mixtures may delay fungicide resistance development and increase genetic diversity, ultimately prolonging the durability of resistance genes. Furthermore, growing mixtures may lower the risk of crop failure due to more extreme weather events and lead to better utilization of water and nutrients. We discuss a Danish case study advocating the cropping of wheat varieties in mixtures as an example of how variety mixtures can be utilized in integrated pest management strategies. The study shows that if all involved stakeholder groups promote the adoption of variety mixtures, a major uptake by farmers can be reached, potentially reducing the dependency on pesticides in current cropping schemes.

Maximum economic yield (MEY) can be extended along two dimensions beyond the common resource stock externality: (1) the appropriate measurement of costs and benefits and (2) extending MEY beyond the relationship between the harvest sector and the resource stock externality. Only when all economic distortions are accounted for and valued by economic (shadow) prices does MEY actually represent a full economic optimum. Accounting for dynamic technical and allocative efficiency extends MEY beyond the traditional dynamic scale efficiency. When accounting for accumulated and new technology and nonmarket public good benefits from biodiversity and ecosystem services, an open question remains whether the MEY resource stock exceeds, equals, or falls short of the MSY resource stock. Without no-growth, steady-state equilibrium, adaptive management is required using non-autonomous bioeconomic models or continuous updating of autonomous ones.

An age structured model of a fishery is studied where two fishing fleets, or fishing agents, are targeting two different mature age classes of the fish stock. The agents are using different fishing gear with different fishing selectivity. The model includes young and old mature fish that can be harvested, in addition to an age class of immature fish. The paper describes the optimal harvesting policy under different assumptions on the objectives of the social planner and on fishing selectivity. First, biomass yield is maximized under perfect fishing selectivity, second, equilibrium profit (rent) is maximized under perfect fishing selectivity, and third, equilibrium profit is maximized under imperfect fishing selectivity. The paper provides results that differ significantly from the standard lumped parameter (also surplus production, or biomass) model.

To what degree might an anticipated policy change delay the fleet restructuring process initiated by a vessel buyback? This paper addresses the issue by estimating a restricted profit function to analyze an overcapitalized fishing fleet subject to restrictive regulation on the harvest of its primary target species. Fishermen’s expectations and likely responses to the future regulations regarding individual quotas are modeled in the context of a time-limited buyback program. The Polish trawler fleet targeting primarily cod provides an application. Analyzing potential individual quota tradability, we find that considerable shifts in disinvestment are to be found due to anticipated policy change. The mechanisms driving discrepancies include capitalized value of quota, as well as the tradability option capitalized into other inputs with inelastic supply.

The purpose of this article is to investigate the link between marine pollution and marine renewable resources. An extended bio-economic model of a fishery is developed to include nutrient enrichment and built into a general model of the polluting and fishery sector with nutrient concentration and fish stock as state variables. The marginal damage function for nutrient enrichment is derived. This function can be compared with the marginal abatement cost and hence it provides a basis for policies that balance the use of nutrients in land-based industries (for example agriculture) with the external cost to the marine environment. The model is empirically applied to the case of the Baltic Sea, where Eastern Baltic cod fisheries are affected by nutrient enrichment. The results indicate that nitrogen loading needs to be reduced slightly (around 1 %) to reach optimal levels. The results also show that the optimal fishery policy plays a more important role in producing the net benefits than nitrogen reduction policies do. Further, the impact on the productivity of the fish stock from pollution reduction is higher when an optimal policy is followed.

The cod stock in the North Sea is threatened by overexploitation. To recover this fishing stock, pressure needs to be reduced. This implies that catch compositions with small amounts of cod are preferred by public policy makers. The present analysis assesses the technological efficiency of fishing trips in terms of the substitution possibilities away from cod by considering landings of cod as an undesirable output. A conservative non-parametric frontier technology approach imposing minimal assumptions and based on directional distance functions is applied to explore alternative fishing activities for Danish gill netters operating in the North Sea with the goal of reducing cod catches. Since performance on different fishing trips may be influenced by the operating environment, a four-stage approach is applied to correct for exogenous factors (Fried et al., J Product Anal 12(3):249–267, 1999). The corrected directional distance function efficiency scores reveal the behavioural inefficiencies, i.e., prospects for decreasing the catch of cod while catch of other species are increased.