bluuebunny/crossref_metadata_2025_split huggingface dataset:
The historical origins of aquaculture
Authors: Kültz Dietmar 
Published: December 2022

AbstractAquaculture developed independently several millennia ago in multiple regions of the world, driven by demand for seafood and by ornamental and religious motives. Good historical records of ancient aquaculture development exist for the Eastern Mediterranean regions of Egypt and Southern Europe, Assyria, China, Southeast Asia, and Oceania. In contrast to terrestrial species, only two aquatic species have been domesticated over many centuries: the goldfish in China and the carp in Central Europe and Eastern Asia. Development of freshwater aquaculture preceded that of mariculture. Aquaculture of catadromous fish has a much longer history than that of anadromous (fish that spawn in freshwater and mature in the ocean) species, though the latter are more commonly cultured today. There are four scenarios, referred to as oxbow, catch-and-hold, concentration, and trap-and-crop theories, that attempt to explain the transition from hunting to farming fish. Evidence exists that ancient societies practised ecologically, highly sustainable, and integrated multi-trophic aquaculture, e.g. in Hawai’i. The industrial revolution not only enabled key technological innovations that supported aquaculture development, but also greatly accelerated the unsustainable exploitation of aquatic resources. Massive transplantation of aquatic species at the dawn of the twentieth century led to the establishment of invasive species with high environmental resilience. The ‘blue revolution’ refers to a surge in aquaculture research and development during the second half of the twentieth century, which resulted in major economic growth of aquaculture businesses accompanied by growing concerns about the sustainability and ecological impacts of this new industry
Seafood and beyond: key aquaculture objectives
Authors: Kültz Dietmar 
Published: December 2022

Abstract
Aquaculture is economically incentivized by growing demand due to 1) human population growth and 2) increased per capita consumption. Aquaculture relieves pressure on capture fisheries and has high potential to be ecologically more sustainable than fishery exploitation of natural ecosystems. The most important aquaculture objective is the production of seafood for human consumption. Seafood has substantial health benefits compared to other sources of nutrition. There exist other significant aquaculture objectives. Aquaculture produces organisms for restocking of lakes, rivers, and the oceans with species of interest and/or concern. Ornamental fish and aquatic invertebrates are produced in aquaculture as companion animals. Jewellery and souvenirs, in particular pearls, are produced from skeletal structures of aquaculture organisms. Aquaculture production of specialized compounds with health or other benefits is practiced for producing nutritional supplements and pharmaceuticals for biomedicine. Moreover, the culture of aquatic microorganisms (bacteria, algae) aids in wastewater treatment and ecosystem restoration. Finally, aquaculture supplies live bait organisms for commercial and recreational fishery.
Integrated multitrophic polycultures
Authors: Kültz Dietmar 
Published: December 2022

AbstractIntegrated multitrophic polycultures represent an ecologically more sustainable form of aquaculture than monocultures; their economic feasibility relies on proper incentivization by policy makers. Polyculture, combined with a shift to culturing omnivores and herbivores instead of carnivores, reduces the unsustainable use of fish meal and fish oil by commercial aquaculture. The ecological value of any polyculture is proportional to the diversity of feeding niches occupied by the cultured species. The most ecologically sustainable form of polyculture combines all primary trophic levels (primary producers, consumers, decomposers) at appropriate ratios in a fully closed system. Decomposers represent critical links for polyculture systems. They fulfil an essential role in nutrient cycles and are cultured in biofilters and artificial reefs as ATS, periphyton, and bioflocs. Research on biochemical capacities of bacterial decomposer communities affords new opportunities for wastewater treatment. Polyculture systems can be coupled or decoupled, and although coupled systems have some advantages, decoupled systems appear more promising for future development of sustainable aquaculture. Aquaculture integration is not limited to polycultures of aquatic organisms but should also be pursued to link aquaculture and alternative uses of water, including drinking, sanitarian, recreational, conservation, industrial, and agricultural uses. Integration of aquaculture and agriculture (IAA) is practised in two forms: 1) wastewater produced by aquaculture is utilized for irrigation of crops and orchards; 2) animal manure produced by agriculture is used to fertilize semi-intensive aquaculture ponds.
Aquaculture of sponges and cnidarians
Authors: Kültz Dietmar 
Published: December 2022

AbstractPorifera (sponges) and Cnidaria (corals and jellyfish) are produced in mariculture as seafood (jellyfish) and for other purposes. Sponges are the most primitive multicellular animals consisting of only a handful of cell types. They often harbour microbial symbionts (bacteria and microalgae). Sponges reproduce sexually and asexually. One mechanism of asexual reproduction (fragmentation) is commonly used for sponge propagation in aquaculture. Bath sponges are farmed in extensive mariculture to obtain their spongin skeleton. Sponges are also farmed in intensive and extensive aquaculture systems to extract a very wide variety of exotic bioactive metabolites that are used to improve human health. Sponge aquaculture is highly ecologically sustainable as sponges are filter feeders (extractive species) and their symbionts contribute to organic waste recycling. It can be further improved by reconditioning wastewater generated from cleaning bath sponge skeletons. Cnidarians are more complex animals than sponges and include jellyfish, corals, and anemones. Jellyfish aquaculture provides seafood by hatchery production of juvenile stages, which are used to restock and supplement natural jellyfish populations that are harvested by capture fishery. Both extensive and intensive aquaculture of ornamental corals and anemones has increased since the turn of the millennium and utilizes transplantation of fragments from donors to initiate cultures. Even though hatchery production of sexually generated larvae would be in many ways preferable, more research is needed for commercial feasibility. Aquaculture of sponges and cnidarians contributes to the conservation of coral reefs and other endangered habitats.
Crustacean aquaculture
Authors: Kültz Dietmar 
Published: December 2022

AbstractCrustaceans are aquatic arthropods that grow in steps rather than continuously by moulting (i.e. by replacing their exoskeleton). Although they are taxonomically highly diverse only few species from the order Decapoda are used for commercial seafood production. Small crustaceans from the order Branchiopoda are used as live food in aquaculture hatcheries. Aquaculture of crustaceans is mostly based on semi-intensive pond culture that utilizes coastal wetlands and has been developed unsustainably during the initial period of rapid growth. Crustacean aquaculture ranks second after fish in terms of value and third after fish and molluscs in terms of production yield. The Western whiteleg shrimp (Litopenaeus vannamei) accounts for more than half of all crustacean aquaculture. Other important species include euryhaline crabs, freshwater prawns, and freshwater crayfish. Shrimps and prawns develop by succession through planktonic nauplius, zoea, and mysis larval stages, while crab development includes planktonic zoea and megalopa larval stages. However, crayfish lack any planktonic larval stages, which simplifies their culture. Hatcheries operating in intensive production mode and nurseries producing juveniles are increasingly utilized for aquaculture of crustaceans before transferring juveniles to grow-out systems. Opportunities for increasing the ecological sustainability of crustacean aquaculture include utilization of recirculating aquaculture systems (RAS) for grow-out, reduction of water used by semi-intensive pond aquaculture, treatment of waste and sludge generated in aquaculture ponds instead of disposal into wild habitat, increased utilization of by-products, improved polyculture systems, increased biosecurity, and utilization of indigenous species.
Ornamental fishes
Authors: Kültz Dietmar 
Published: December 2022

Abstract
Aquaculture of ornamental fishes is rapidly expanding because of large demand and the much greater value of ornamentals relative to seafood fishes (per kg fish produced). Aquaculture of ornamental fishes is well suited for ecologically sustainable recirculating aquaculture systems (RAS). Technological innovations have made marine aquaria readily accessible for hobby aquarists, but they are still more challenging to maintain than freshwater aquaria. Thousands of different marine and freshwater ornamental fish species are being traded. Aquaculture accounts for &gt;90% of all ornamental freshwater fishes but &lt;10% and fewer than fifty species of all marine ornamental fishes. Several ornamental freshwater fishes have been domesticated, including betta fish, freshwater angelfish, guppies, and discus cichlids. Ornamental fish domestication is facilitated by short generation times. For marine ornamentals, research on husbandry and hatchery methods is needed to address environmentally destructive methods of capture fisheries in coral reef habitats. Advantages of ornamental fishes produced by aquaculture include species and habitat conservation, reduction of transport-related stress and mortality, improved animal welfare, elimination of pathogens and better health, known young age, being accustomed to life in aquaria and the presence of people, and being amenable to domestication for artificial selection of desirable traits. Diversification is essential for ornamental aquaculture to accommodate large fluctuations in demand for certain species. Many ornamental species have become invasive. Their management and preventative measures for avoiding future invasions of additional ornamental species are very challenging but essential for supporting the ecological sustainability of ornamental fish aquaculture.
Freshwater fishes
Authors: Kültz Dietmar 
Published: December 2022

AbstractFreshwater (FW) aquaculture has greater potential than mariculture for intensifying production in ecologically sustainable systems that utilize available know-how and technologies. FW fishes used for aquaculture are positioned lower in trophic webs and, thus, require fewer resources than most catadromous, anadromous, and marine aquaculture fishes. Carp, tilapia, and catfish are the most important FW fishes used for aquaculture. They are farmed mostly in semi-intensive, open pond systems that rely heavily on ecosystem services. FW fish aquaculture is often divided into hatchery, nursery, and grow-out phases. Reproduction of carp, tilapia, and catfish broodstock is performed by natural spawning or artificial fertilization. In carp and catfish, injection of pituitary hormones induces ovulation and spawning. Carp and tilapia species dominate animal aquaculture and are often raised in polycultures to better utilize resources by taking advantage of different feeding habits and food preferences. Polyculture of carp and tilapia with rice and azolla improve resource utilization by integrating primary producers with heterotroph consumers into aquaculture nutrient cycles. Tilapia, carp, and catfish have high environmental stress tolerance and are ideal for a wide variety of aquaculture systems. However, their high environmental stress tolerance also promotes invasiveness. Premature reproduction of tilapia is problematic for aquaculture and promotes invasiveness. It has been addressed by producing single-sex (mostly all male) populations using multiple approaches. Catfish aquaculture has shifted from an initial focus on channel catfish in the second half of the twentieth century to Asian torpedo and shark catfish, which have superseded channel catfish in value and yield.
Anadromous fishes
Authors: Kültz Dietmar 
Published: December 2022

AbstractAnadromous fishes hatch and develop in freshwater (FW) and migrate to seawater where they spend most of their life before returning to FW for spawning. In contrast to trout, most salmon are anadromous. Atlantic salmon (Salmo salar) dominates aquaculture of anadromous fishes and is produced mainly in its native distribution range. Most Pacific salmon are produced in the Southern hemisphere, outside their native distribution range. Salmon aquaculture consists of a FW hatchery phase and a seawater grow-out phase. These different culture phases are required for all anadromous species. The most critical stage of salmon development in a FW hatchery is the alevin stage. At this stage, mortality is highest and yolk sac larvae are trained to consume starter feeds. Smoltification (silvering) is the physiological process of salmon parr transforming to smolts ready to enter seawater. Smoltification is essential for the anadromous life history of salmonids and precedes translocation of aquaculture salmon from FW hatcheries to open marine cages. Rainbow trout (Oncorhynchus mykiss) is the second-most produced salmonid aquaculture species. Most rainbow trout are grown in open, flow-through FW hatcheries and raceways, although anadromous rainbow trout (steelhead trout) are grown-out in mariculture. Salmonids are carnivores that occupy high levels in trophic webs, require high water quality, strong flow, and high-quality feeds. From an ecological sustainability perspective, salmonids are more challenging and more resource-intensive than herbivorous FW fishes. Consumer preference and demand for salmonids is high, which has fuelled research to reduce water usage, minimize waste, and develop more sustainable feeds.
Catadromous and marine fishes
Authors: Kültz Dietmar 
Published: December 2022

Abstract
Catadromous fishes reproduce in the ocean and migrate as larvae or juveniles to coastal brackish and inland freshwater habitats before returning to the ocean as adults. Catadromous migration varies between and within marine fishes. Catadromy is pronounced in river eels, milkfish, and mullets, while other fishes are amphidromous (i.e. their migrations are opportunistically driven by trophic conditions). Aquaculture of amphidromous species includes carnivores in the order Perciformes and flatfishes (Pleuronectiformes). Two species of catadromous river eels dominate eel aquaculture: the European eel (Anguilla anguilla) and the Japanese eel (A. japonica). A. anguilla reproduces in the Sargasso Sea of the Atlantic Ocean, while A. japonica spawns at the Suruga Seamount in the Pacific Ocean. Larval development takes many months during migration toward the coasts of Western Europe and Eastern Asia, respectively. Captive eel reproduction has been advanced, but its commercial adoption is not yet feasible. Thus, river eel aquaculture depends on capture of glass eels or elvers. Semi-intensive approaches and recirculating aquaculture systems (RAS) and are used for eel aquaculture. Catadromous milkfish (Chanos chanos) is primarily a herbivore occasionally feeding on zooplankton. Advantages of milkfish for aquaculture include high stress tolerance, disease resistance, and rapid growth. Milkfish aquaculture has a long history in Southeast Asia. Specialized hatcheries produce milkfish fry for aquaculture, which relieves pressure on natural populations but requires careful genetic management. Milkfish grow-out is performed in semi-intensive ponds or cages. Despite the generally smaller ecological footprint of milkfish aquaculture, consumer preference for milkfish is lower than for carnivores.
Feeds, waste, and stress
Authors: Kültz Dietmar 
Published: December 2022

AbstractThe main input of energy and matter (excluding water and oxygen) in aquaculture systems are fertilized eggs, food, and fertilizer, while waste and harvest represent the main output. Aquaculture systems are classified by stocking density, yield, space efficiency, and the extent of reliance on ecosystem services or technology. Ecologically sustainable aquaculture is promoted by collection, processing, and proper disposal of waste and by trophic recycling of waste within the system. Intensive recirculating aquaculture systems (RAS) and extensive aquaculture are most ecologically sustainable. Semi-intensive, open, cage, raceway, and net pen aquaculture systems are least ecologically sustainable. Aquaculture sustainability is increased when feed efficiency is maximized, and feed conversion rate minimized by optimal composition, consistency, and application of food. Live food is critical in hatcheries for feeding larvae. It consists of phytoplankton (microalgae) and zooplankton (rotifers, brine shrimp, and copepods). Formulated aquaculture feeds containing optimal amounts and ratios of amino acids, proteins, lipids, carbohydrates, minerals, vitamins, and other essential nutrients have been developed. An optimally nutrient-balanced diet based on formulated feeds maximizes the health of aquaculture animals. Aquaculture waste is produced from unused decaying food, excreted animal waste, and decaying plant, bacterial, and animal biomass. Aquaculture waste is treated by mechanical filtration and sedimentation, biological filtration, chemical filtration, degassing, oxygenation, and sterilization. Stress induced by poor water quality impairs the welfare and performance of aquaculture organisms. Universal, non-specific symptoms of stress are routinely monitored in aquaculture. They include animal behaviour and appearance, haematocrit, lymphocyte counts, and plasma cortisol and glucose concentrations.
Infectious diseases
Authors: Kültz Dietmar 
Published: December 2022

Abstract
Infectious diseases are responsible for the loss of almost half of all aquaculture production. Their incidence can be minimized by strict biosecurity in closed recirculating aquaculture systems (RAS). Infections are caused by pathogens transmitted by physical contact or biological vectors, either horizontally (within the same generation) or vertically (from parents to offspring). Many infectious pathogens are present in the environment, but healthy aquatic animals suppress them by employing pathogen defence mechanisms such as physical barriers and immunity. Immunity is compromised by stresses encountered in aquaculture. Adaptive immunity is based on cellular memory and limited to vertebrates (aquaculture fishes) while innate immunity and physical defences are also utilized by invertebrates. Four types of pathogens cause significant infectious diseases of aquaculture organisms: viruses, bacteria, fungi, and parasites. Diagnosis of viroses, bacterioses, mycoses, and parasitoses uses PCR, cytopathic effects in host cell lines, growth on selective media, microscopy in combination with specific stains, and visual inspection of hosts (e.g. to observe ectopic macroparasites). Treatment includes antibiotics, medicated feeds, chemotherapeutic, saline, or oxidative baths, and co-culture with cleaner fish. Prophylaxis is the best and sometimes the only (e.g. viroses) approach for minimizing disease problems in aquaculture. It is based on implementing biosecurity, sanitary management, quarantine, water sterilization, disinfection, stress reduction, regular monitoring, domestication of disease-resistant strains of aquaculture organisms, and utilization of specific pathogen-free (SPF) stocks of aquaculture organisms.
Awakening to China's Rise
Authors: Meijer Hugo 
Published: December 2022

Abstract
Awakening to China’s Rise delivers the first post-Cold War history of how Europe’s major powers (Britain, France and Germany) have responded to the security challenges posed by China’s rising assertiveness both in the Asia-Pacific and in Europe. A longstanding assumption in the IR literature has been that European foreign policies towards the People’s Republic of China (PRC) have been driven by a ‘naïve’ and self-interested focus on the economic opportunities presented by such a vast market, overlooking security considerations. This book challenges this common belief through a detailed examination of the policies of France, Germany and the United Kingdom from 1989 to the present. Its central argument is that, whereas this assessment aptly characterized the first two post-Cold War decades, Beijing’s growing assertiveness after 2009 caused the three major European powers to awaken to the security implications of China’s rise. Throughout the 2010s, heightened threat perceptions of China, coupled with increasingly competitive bilateral economic relations with the PRC, have gradually and cumulatively caused the hardening of their policy goals which, in turn, translated into the formulation of new, more stringent policy instruments to confront such a challenge. To substantiate this argument, this book puts forward a unique cross-regional comparison. It examines and compares the evolution of their foreign and security policies in two key regions. (1) Chinese assertiveness in the Asia-Pacific: it analyses their response to China’s increasingly muscular regional posture in the Asia-Pacific through the development of diplomatic and security cooperation initiatives with partners in the region. (2) Chinese assertiveness in Europe: it delineates how the Big Three have confronted China’s inroads into Europe, looking at the measures that they have taken to tackle the security challenges posed by Chinese investments in, and supply of, technologies in strategic sectors such as critical national infrastructures, dual-use technologies, and in the digital domain, including 5G networks. To do so, this book relies on a large body of previously undisclosed primary sources, including: 223 interviews conducted with senior officials in Europe (Berlin, Brussels, London, Paris), in the United States (Washington, DC), and in Asia (Beijing, Shanghai, New Delhi, Seoul); declassified archival documents from France, the UK and Germany; leaked US diplomatic cables; and new data on European naval deployments.
Introduction
Authors: Meijer Hugo 
Published: December 2022

Abstract
The Introduction of the book first sets the scene by characterizing the geostrategic context within which the foreign and security policy towards China of Europe’s major powers have unfolded, identifying three core macro-dynamics: the gradual retrenchment of the United States from Europe since the end of the Cold War—coupled with growing doubts about the credibility of US commitments to the continent—which has incited Europe’s major powers to provide for their own security; China’s increasingly assertive foreign policy behaviour both in Europe and in the Asia-Pacific since the late 2000s/early 2010s; and the rising global competition between the United States and China, which has become a structural feature of great power politics in the twenty-first century. Stuck between a rock and a hard place, Europe’s major powers therefore increasingly doubt the robustness of the US ally’s commitment to their security while grappling with China’s increasingly assertive behaviour in the larger context of mounting Sino-American rivalry, and are thus compelled to define their own position therein. The Introduction then presents the book’s research question and central argument, delineates the study’s intellectual contribution, and details the wide range of primary written and oral sources upon which it is based.