The economic and environmental sustainability of aquaculture depends significantly on the nature and quality of the fish feed used. One of the main criticisms of aquaculture is the need to use significant amounts of fish meal, and other marine protein sources, in such feed. Unfortunately, the availability of the oceanic resources, typically used to produce fish feed, cannot be utilized indefinitely to cover the worldwide feed demand caused by ever-increasing aquaculture production. In light of these considerations, this study estimates how aquaculture farm economic outcomes can change by introducing insect meal into the diet of cultivated fish. Several possible economic effects are simulated, based on various scenarios, with different percentages of insect flour in the feed and varying meal prices using a case study of a specialized off-shore sea bass farm in Italy. The findings indicate that the introduction of insect meal—composed of Tenebrio molitor—would increase feeding costs due to the high market prices of this flour and its less convenient feed conversion ratio than that of fish meal. Therefore, the expected environmental benefits of using this highly promising insect meal in fish feed do not align with the current economic interests of the aquaculture industry. To our knowledge, this is the first study to investigate this theme, and it must be noted that our findings cannot be generalized widely because a specific case study was used. Nevertheless, our findings suggest that efforts should be made—at least at the farm level—to find profitable ways to encourage the introduction of this attractive alternative to guarantee both economic and environmental sustainability in the near future.

The studies focused on the use of insects have outlined numerous reasons for using insects as food and feed as an important method to increase food opportunities for consumers. Insects have been emphasized as a food source with a low environmental impact due to the limited requirement for arable land and water, low ecological cost, and high-quality protein provision. In Europe and Western countries, insect farming is a growing business in which, however, some critical economic aspects must be recognized. The sector needs to be adequately promoted to rationally exploit the huge amount of potential. As such, the aim of this study was to analyze the recent research on economic aspects related to insect farming for feed and food production with the purpose of providing evidence of the critical economic points in this emerging sector. The focus was mainly oriented to understanding how insect farming can foster virtuous circular economic processes, specifically considering economic aspects on the basis of the limited literature currently available and the circular economic principles. A circular business model approach was proposed to address the entire insect-based feed and food supply chain from a circular economic perspective. In our opinion, the findings underline some economic research questions that need to be addressed in the near future, and the conceptual approach can be individualized to help increase cost- and eco-effectiveness from a circular economic perspective.

Environmental pollution, population increase, water availability and misuse of land are inexorably driving humans to take on important challenges related to sustainability. The next future is expected to see a significant increase of food and feed demands, which determines a serious threat to well-being levels and even survival of modern societies. Within this scenario, the efficient and sustainable use of insects as protein sources has been invoked as a possible strategic solution. As a candidate for remarkable growth, insect farming promises significant benefits to agri-food industry, offering interesting opportunities for implementing circular economy. In the present work, we review selected literature on insect rearing with the aim of providing a short rigorous introduction to the field to researchers, entrepreneurs and common readers. After a general overview of the field, including a description of insect nutritional values, the review focuses on the three insect species that are seemingly set to beneficially affect aquaculture, which is the activity presently more sensitive to circularity and sustainability innovation. Once traditional and advanced insect rearing methods are described, the challenges that the field is going to tackle are suitably highlighted.

This paper aims to evaluate the technical efficiency and the total factor productivity change of dairy farms in EU countries. Analyses were carried out in order to determine which countries showed the best performance adaptations when the quota regime was relaxed and to evaluate the technical conditions of European farmers at the starting point of the new regime (milk quota abolition). A data envelopment analysis (DEA) was applied on aggregate data related to 22 European countries for the period from 2004 to 2012. The findings suggest that milk farms show small scope for improving efficiency using their own technical input. The estimation of total factor productivity and its components suggest that the European milk sector has suffered a decline in productivity. This means that external factors, independent of the farmers' capacity to use technical inputs, can play a greater role than efficiency in conditioning productivity and profitability in the near future.

Coastal management is "that process of managing a beach, whether by monitoring, simple intervention, recycling, recharge, the construction and maintenance of coastal control structures or by some combination of these techniques, in a way that reflects an acceptable compromise in the light of available finance, between the various coastal defence, nature conservation, public amenity and industrial objectives" (Micallef and Williams, 2002;Simm et al., 1996). This definition seems to consider the entire spectrum of coastal conflict in that it addresses social, economic and environmental aspects of beaches as socio-ecological systems (SES) (e.g. Defeo and McLachlan, 2005;Botero and Hurtado, 2009). This approach considered beaches as multidimensional systems linked with and affected by one or more social systems where natural, socio-economic and administrative components interact (Micallef, 1996;Micallef and Williams, 2002;Williams and Davies, 1999). Approaches to the management of beach as SES have traditionally focused on a very limited number of functions, such as beaches as summer playgrounds and buffer spaces for storms (James, 2000;Lozoya et al., 2014;Ariza et al., 2016). However, from the last century, beaches were expressly defined as SES especially due to new methodologies for capturing beach complexity in order to provide information Willingness to pay for management and preservation of natural, semi-urban and urban beaches in Italy Ilaria Rodella a, *