As world energy demand continues to rise and fossil fuel resources are depleted, marine macroalgae (i.e., seaweed) is receiving increasing attention as an attractive renewable source for producing fuels and chemicals. Marine plant biomass has many advantages over terrestrial plant biomass as a feedstock. Recent breakthroughs in converting diverse carbohydrates from seaweed biomass into liquid biofuels (e.g., bioethanol) through metabolic engineering have demonstrated potential for seaweed biomass as a promising, although relatively unexplored, source for biofuels. This review focuses on up-to-date progress in fermentation of sugars from seaweed biomass using either natural or engineered microbial cells, and also provides a comprehensive overview of seaweed properties, cultivation and harvesting methods, and major steps in the bioconversion of seaweed biomass to biofuels.
Digital library
-
-
A method is described for saving 30% of the world fish catch by producing fishmeal and fish oil replacement products from marine microalgae, the natural source of proteins and oils in the marine food web. To examine the commercial aspects of such a method, we adapt a model based on results of microalgae production in Hawaii and apply it to Thailand, the world's fourth largest producer of fishmeal. A model facility of 111 ha would produce 2,750 tonnes yr-1 of protein and 2,330 tonnes yr-1 of algal oil, at a capital cost of $29.3 M. Such a facility would generate $5.5 M in average annual net income over its 30-year lifetime. Deployment of 100 such facilities in Thailand would replace all domestic production of fishmeal, 10% of world production, on ~1.5% of the land now used to cultivate oil palm. Such a global industry would generate ~$6.5 billion in annual net income.
-
A study of marine benthic plants collected from Pohnpei Island and Ant Atoll, Federated States of Micronesia, between 1994 and 1997 documented the occurrence of 59 species of green algae (Division Chlorophyta), 16 species of brown algae (Division Phaeophyta), and 3 species of seagrasses (Division Magnoliophyta). Based on these collections and a review of the literature, the marine flora of Pohnpei now comprises 52 Chlorophyta species, 22 Phaeophyta species, and 3 seagrass species; and the list for Ant Atoll currently stands at 60 Chlorophyta species, 11 Phaeophyta species, and 2 seagrasses. New records include 20 species from Pohnpei, and 30 from Ant. Of these, 8 were taxa previously unknown from Micronesia: Caulerpa microphysa (Weber-van Bosse) J. Feldmann, Derbesia fastigiata Taylor, Dictyota acutiloba J. Agardh, Enteromorpha flexuosa (Roth) J. Agardh, Padina boergesenii Allender & Kraft, Percursaria dawsonii Hollenberg & Abbott, Ulothrix flacca (Dillw.) Thuret, and Ulvella setchellii Dangeard. Red algae (Division Rhodophyta) were also collected, and will be reported in a future paper.
-
This is the second paper resulting from a study of marine benthic plants collected from Pohnpei Island and Ant Atoll in the Caroline Islands, Federated States of Micronesia, between 1994 and 1997. It documents the occurrence of 113 species of red algae (Division Rhodophyta), exclusive of crustose coralline algae. Of these, 56 are new records for Pohnpei, 76 are new records for Ant Atoll, and 53 are new records for Micronesia (here including the Caroline, Mariana, Marshall, Gilbert, and Ellice Islands). A previous paper reported 80 species of green and brown algae and seagrasses from Pohnpei and Ant, of which 8 were new records for Micronesia. Added to reports from the literature, the total known marine benthic flora of Ant and Pohnpei (exclusive of Cyanobacteria and crustose coralline algae) now stands at 244. The high volcanic nature of Pohnpei is very different from the low calcareous Ant Atoll, which led us to expect higher species numbers for Pohnpei relative to Ant, and greater differences in their algal floras than we found. Comparisons of the Ant-Pohnpei algal flora were also made, using the Jaccard and Sorensen’s indices, to Ifaluk Atoll (Caroline Islands), Enewetak Atoll (Marshall Islands), the Northern Mariana Islands, and the distant south Pacific island groups of Fiji and French Polynesia. Biogeographic investigation of the marine plant flora revealed that Ant Atoll and Pohnpei have a large number of widespread and Indo-Pacific species, but very few probable regional endemics
-
Very delicate and complicated relationships underlie the universe in which marine plants and animals dwell; nowadays inhabitants of the World Ocean too often surrender, being unable to withstand human pressures and consequent impacts.
Everyone who steps from the beach into the sea meets algae and seagrasses, those basic primary producers which account for proper functioning of the coastal marine ecosystem. Seaweeds and seagrasses are coastal resources of inestimable value throughout the world. They create stable habitats for many types of food chains that support the goods and services of marine ecosystems (commercial species, recreation, utilization of land-based and ship-borne pollution, etc.). These marine plants also stabilize bottom sediments thus preventing coastal erosion, and aid in maintaining clear coastal waters since they buffer strong currents and wave action. The extremely high biodiversity of seaweed communities is well known. Besides, a variety of marine plants are used as food and for chemical compounds required in many industries. The first records about using seaweed and seagrass as medicinal agents were made about two thousand years ago.
The greatest risks for disruption and extinction of marine plants are in the shallow coastal zones which, along with estuaries, are the places where most of the high concentrations of population occur in the world. This is where shipping and port activities take place, where large rivers end after draining vast areas of agricultural activities, and where largest tourist resorts are located. The loads resulting from human activities, marine traffic and tourism coupled with the global climate change have disturbed the coastal seaweed and seagrass communities significantly in the long-term run. Regrettably, many countries ignore the ecological importance of the coastal zone and abandon any activity that suggests conservation of the seaweed beds. The recent oil blowout and spill in the Gulf of Mexico has demonstrated how human activity may kill off marine life; the most gravely endangered are semi-enclosed seas, e.g., the Black Sea, which is one of the worst polluted seas in the world. Therefore, preserving and conserving the diversity of the Black Sea life is a challenge of special importance.
Though key species of marine plants and their natural habitats in the Black Sea have been placed under protection of regional and national laws and international conventions, too many underwater communities along the shoreline are still affected by degradation. Marine protected areas (MPAs) have proved efficient in preserving, restoring and maintaining the biological diversity but at present their total area is not large. Their expansion through the Black Sea net of MPAs acquires high priority in nature conservation.
Unacceptably, present legislation level of designation of MPAs fail to adequately preserve the diversity of marine organisms. Besides, the general public awareness is low, people are not well challenged to acquire and enlarge their knowledge of plants and animals inhabiting the sea, their 9 life cycles and natural habitats. Marine biologists should better communicate their research on underwater life to public–today the number of illustrated manuals describing seaweeds and marine life is insufficient. This Guide was written to bridge this gap and acquaint the reader with common seaweed and seagrasses of the Black Sea.
Chapters of this book describe the Black Sea, marine plants growing on the sea floor, commercial use and protection and techniques which are applied to prepare a seaweed herbarium. The most extensive part of the Guide describes 74 macroscopic marine plants which are widespread along the shorelines of the Black Sea and form extensive beds and communities. They belong to the Kindom Plantae (Phylum Chlorophyta, Rhodophyta and Magnoliophyta) and Kindom Chromista (Phylum Heterokontophyta).
Species names are cited in alphabetic order and in concordance with the recent taxonomic revisions and nomenclature alterations synonyms are also given. The descriptions include details of the taxonomy, morphology, ecology, vegetation, reproduction, distribution and economic use. In compiling this Guide, the author used her own materials and data as well as thematic handbooks, monographs and other references. Almost each species is illustrated with underwater photos that permit identification of the marine plant. Most of the photos are from the archives of the Laboratory of Phytoresources (Institute of Biology of the Southern Seas, IBSS).
Annexes to the Guide include a list of researchers working in different fields of marine biology, an MPAs inventory for the Black Sea, the pertinent international conventions and agreements on preservation of the biological and landscape diversity. The glossary explains special scientific terms. The names and publications of all those who contributed to the general topics of the Guide are included in the references section.
The author was fortunate enough to had been taught by friendly and competent tutors in marine biology and to work in cooperation with colleagues who are as enthusiastic as I am. As a student of Rostov-on-Don State University, I repeatedly went to IBSS, one of the oldest European marine research institutes. Later, in this Institute I have specialized in biology and the ecology of the Black Sea marine plants. Some of the results obtained are included in this Guide and may be of use to algologists, ecologists, hydrobiologists, specialists in nature protection management, students, and to anyone sincerely interested in marine life.
I would appreciate any comments or suggestions from interested readers.
-
Research undertaken in West Coast states and British Columbia suggests the best entry level markets for high quality seaweeds are in North America food markets. These markets could be targeted by future Alaska marine plant businesses selling high-value specialty products. Long term, the experiences gained in domestic markets could then be directed at niche Asian marine plant markets.
Alaska has an excellent reputation as a source of high quality, sustainable seafood with outstanding brand recognition. Building on this international brand, economic opportunities in specialty food markets for Alaska sea vegetables and fertilizer concentrates holds the highest potential for success among entrepreneurs and coastal communities alike. However, before scaled up operations occur, state resource agencies still need to learn more about the number, quantity, and types of commercial marine plants in Alaska, establish total allowable harvest limits for sustainable wild seaweeds, and help to identify financing opportunities to assist an emerging wild aquatic plant and mariculture industry.
-
Utilization of marine algae has increased considerably over the past decades, since biodiversity within brown, red and green marine algae offers possibilities of finding a variety of bioactive compounds. Marine algae are rich sources of dietary fibre. The remarkable positive effects of seaweed dietary fibre on human body are related to their prebiotic activity over the gastrointestinal tract (GIT) microbiota. However, dietary modulation of microorganisms present in GIT can be influenced by different factors such as type and source of the dietary fibre, their molecular weight, type of extraction and purification methods employed, composition and modification of polysaccharide and oligosaccharide. This review will demonstrate evidence that polysaccharides and oligosaccharides from marine algae can be used as prebiotics, emphasizing their use in human health, their application as food and other possible applications. Furthermore, an important approach of microbial enzymes employment during extraction, modification or production of those prebiotics is highlighted.
-
Northern Bluefin Tuna (NBT, Thunnus orientalis) are found in the Eastern Pacific Ocean (EPO) from the Gulf of Alaska to southernBaja California and in the Western Pacific Ocean (WPO) from the Sakhalin Islands to the northern Philippines. They are usually oceanic but seasonally come close to shore, school by size, and tolerate a wide range of temperatures. They spawn in the WPO in the vicinity of Okinawa, Japan and the Philippine archipelago, then disperse to other areas of the WPO. Some fish apparently remain their entire lives in the WPO, while others migrate to the EPO during their first and second years of life. Fish in the EPO have an increasingly restricted north-south distribution as they grow older. Migrations between and within the WPO and EPO are related to oceanographic and prey conditions. Fish migrate back to the WPO between ages 2-3. During El Niño events, NBT are distributed further to the north in the EPO and catches decrease. Large impacts related to changes associated with global warming may limit the amount of NBT available off Baja California. Japan currently accounts for about 64% of the catch of NBT in the North Pacific Ocean (NPO). The other two nations involved in this fishery to a significant degree are Taiwan and Mexico. Catches historically have been 2-3 times higher in the WPO than in the EPO. The catch in the EPO in 2006 was ~10,000 metric tons (MT). Most of the catches in the EPO are fish of ages 1-3. Modeling studies have shown that a strong recruitment event occurred in 2001 and couldmaintain NBT spawning stock biomass until ~2010. The results of yield-per-recruit and cohort analyses indicate that greater catches in the NPO could be obtained if the catches of ages 0 and 1 fish were reduced or eliminated, mainly in the WPO. Increased fishing pressure on NBT juveniles from CBTA would not necessarily decrease recruitment, since spawner-recruit analyses indicate that the recruitment of NBT would not necessarily increase by permitting more fish to spawn. Even though fishing mortality (F) has been higher than FMAX,, or is above the reference point, recruitment overfishing has not occurred. Nevertheless, itis recommended that fishing mortality not be further increased and catches reduced. According to international institutions (IATTC, ISC and FAO), NBT is “Fully Exploited”. NBT is notincluded on the IUCN red list. There is no scientific evidence thatNBT are overfished in the NPO. Estimated retained catches of NBT have fluctuated widely between 500 and 10,000 MT in the EPO over the last 30 years (from 1976 to 2006). Regarding the CBTA activity, there is no evidence that it has affected the NBT stock since its beginning in 1996. Considering that not all NBT migrate to the EPO, increasing the catch of NBT would not necessarily decrease recruitment. Current CBTA productionlevels do not appear to compromise the NBT stock. However, catches of NBT juveniles and fishing effort should be regulated and not be increased, both in the WPO and EPO. Most of the capture-based tuna aquaculture (CBTA) facilities in Baja California use fresh, locally-caught Pacific sardine (Sardinops sagax caerulea) as feeds. Pacific sardines are oviparous, multiple-batch spawners that can reach a maximum size of 41 cm with a life span of 14 years. Fecundity is size and age dependent. Older fish spawn more times during a year, with spawning dependent onwater temperatures. Most recent stock assessments show that the stock productivity ofPacific sardines (recruits, age-0 fish, per spawning biomass) is declining, with stock spawning biomass (age +1) leveling off at 1.06 million metric tons (MT) in 2005. Studies suggest that the equilibrium of the spawning stock biomass and potential sustainable yield are dependent on environmental conditions. Recruitment success isvariable in long, decadal, time scales, depending on oceanographic conditions. There are three stocks of Pacific sardines. The sardine fishery based in Ensenada is the northernstock of this species. This stock is also fished by the USA and Canada. Other solely Mexican sardine fisheries comprise the southern and Gulf of California stocks. The fishery in Ensenada has traditionally been based on catches of small Pacific sardines of the northern stock. There are a high proportion of juveniles in these catches, since Ensenada vessels operate close to the coast (less than 40 nautical miles). Studies suggest that older and larger sardines move offshore where little fishing effort is currently occurring. Traditionally, the Mexican catch has been used for reduction to fishmeal and oil, canned for human consumption, or used fresh for bait. Landings of Pacific sardines at Ensenada increased from an annual average of 2,133 MT during the 1980s, to an average of ~48,000 MT in the 1990s. Landings decreased to ~41,000 MT during 2003 and 2004 and rose to 57,000 MT in 2006. Management of the Pacific sardine fishery inMexico incorporates several measures, including minimal sizes, closed seasons, and moratoriums on efforts. Fresh Pacific sardines have become important resources for CBTA in Mexico. In 2006, ~53% of the Pacific sardines landed in Ensenada were used for CBTA. However, this is likely an underestimate. Some catches were not recorded when they were delivered directly to the CBTA cages. Recently, a new Baja California State sardine fisheries committee that included fishing and frozen fish processing companies was reorganized to include CBTA in the management of the Mexican portion of the northern Pacific sardine stock. CBTA effects the marine environment and marine species associated with farm sites (sea mammals, marine birds, and marine organisms that inhabit the water column and benthos). Unconsumed or macerated sardines and fish feces are the main sources of solid, suspended, and soluble wastes. However, this waste stream is quite different from other, commercially fed finfish aquaculture such as salmon: tuna farming is seasonal; does not use antibiotics, chemicals, or any agricultural pesticides or additives; and it depends on natural feeds (sardines). Soluble nutrients are commonly detected only in close proximity to the tuna cages and dissipaterapidly. However, changes in the benthic community derived from enrichment of waste organic matter to the sediments could be more persistent, and even a 6 month fallow period may not be sufficient for the benthic community to recover. The extent of the increase in benthic enrichment is still to be determined since accumulations of tuna farming wastes are strongly dependent on the hydrodynamics and oceanographic characteristics of the farm site, and farm management practices, and no such studies have been done. Non-lethal methods of controlling marine mammals, such as placing high nets and electrified wires around the cages have effectively discouraged sea lions. The non-lethal use of whips and sounds to reduce bird predation on sardines are additional, successful measuresthat ranchers have implemented to avoid conflicts with protected species. CBTA has a number of environmental, social and economic impacts which can be considered as positive or negative, as judged by society. CBTA is a new economic activity within the fisheries sector of Baja California, México which has brought new jobs. CBTA is closely monitored by the federal authorities, and the management is carried by the proper government agencies. A new Mexican law onsustainable fisheries and aquaculture addresses CBTA. All CBTA farms in Mexico are required by law to monitor marine water quality and sediments; monitoring programs must be verified by both the Mexican Navy and the Ministry of the Environment. To date, neither agency has declared any negative environmental action on any of the tuna farms. Governance of tuna ranching in Mexico is still underdeveloped; several issues need to be addressed in order to assure a minimum impact on the environment, especially in regards to better scientific determinations of the carrying capacity of each site, and development of better technological and management alternatives to reduce the impact of fish wastes on the benthos.
-
Marine sponges have a long history of farming, starting with bath sponges over 5000 years ago in the Mediterranean. Many species have since been found appropriate for distinct types of commercial assessment. Drug development relies on the isolation of sponge-derived secondary metabolites as natural compounds having a wide range of ecological functions, from deterring predation to preventing microbial infection/proliferation on the sponge body. For human society, they feature a broad array of pharmacological properties with some applications still being discovered. Their limited supply has however been faced as a major obstacle to the conduct of clinical trials. Marine aquaculture has to prove more integrated and sustainable to remain an interesting way to ensure sufficient amounts of biological substances for the early processing and production of drugs. This review presents sponge farming methods that were tested, the undergoing challenges they faced and the interest they raised on environmental and metabolic factors to explain contrasting spatiotemporal performances. Through global experiments, sometimes involving other marine organisms, technicity of sponge aquaculture has long been evolving to ensure efficient and cost-effective strategies. Further ways to make sponge farming more attractive and diversify its commercial applications are investigated, such as recent studies in collagen or chitin production for bone tissue engineering or bioremediation as an alternative to existing wastewater management. Overall, marine sponges exhibit astonishing intra and interspecific variation, which is why they should be considered with respect to the purpose of their economic valuation, their environmental context and all the symbiotic interactions they rely on.
-
Marine tenure and the role of marine protected areas for sea cucumber grow-out in the Pacific region
Many Pacific island countries are reviving longstanding customary marine resource management systems and traditional tenure through the locally managed marine area (LMMA) approach. The customary tenure systems vary: some are formally recognised in national laws, while for others the recognition is informal. These practices include seasonal bans on harvesting, temporarily closed (no-take) areas, and restrictions placed on certain times, places, species or classes of persons. The LMMA demonstrates the shared vision of stakeholders that promotes the success of adaptive management, as evidenced by healthy ecosystems and communities, abundant marine and fish stocks, sustainable fisheries utilisation, protected marine biodiversity, sustainable development in coastal communities, an understanding of what communities are doing and can do in managing marine areas, and an understanding of ecological and socioeconomic responses to LMMA and coastal management implementation. The LMMA approach helps to ensure that benefits from marine conservation efforts will accrue to the local community, generally in an equitable manner, benefiting them spiritually, culturally, communally, socially and economically. A Fijian site in Verata district revealed that, since 1997, there has been a 20-fold increase in clam density in the tabu areas, a 200−300% increase in harvest in adjacent areas, a tripling of fish catches, and a 35−45% increase in household income. Similar trends have also been observed in the other tabu areas across Fiji in a range of potential marine commodities, such as giant clam, seaweed and coral transplanting. Currently, there are more than 200 traditionally imposed LMMAs, including tabu areas, and numbers continue to grow.
In Fiji, application of the LMMA approach at Natuvu village on the island of Vanua Levu has demonstrated how a customary tenure system can be integrated with sea ranching of sandfish in a closed area. The entire process can be governed by Fijian customary institutions and laws that incorporate local socioeconomic considerations, and provide more diverse and culturally appropriate approaches to enforcement, compliance, monitoring and restitution. The effectiveness of traditional practices is a reflection of the strength and viability of the customary law regime. There may also be issues regarding enforcement, the viability of a closed area in the long term, and the roles taken by governments, communities and traditional leaders. Traditional practices are generally accompanied by strategies and resources to support sustainable use, viable livelihoods and equitable sharing of benefits.
Pages
Marine Agronomy Group, CAFNRM, UH-Hilo
200 W. Kawili st., HI 96720, USA
Contact: Marine.Agronomy.Group@gmail.com
Funding for this web portal is provided by the World Wildlife Fund and the University of Hawaii-Hilo.