This paper elaborates on the inseparable link between sustainability of natural resources and food security. A strategic framework that envisages conservation, improvement and sustainable uses of natural resources is proposed which meets the essential requirements for food security. Sustainability has traditionally been accepted as encompassing three dimensions, namely environment, economics and society but it is necessary to widen this approach for a more complete understanding of this term. Environmental degradation curtails ecosystem services, leading to impoverishment of vulnerable communities and insecurity. Food, whether derived from land or sea, is a product of complex environmental linkages, and biodiversity has a pivotal role to play in producing it. Technology, production methods and management requirements are different for food derived from land and sea, but essentially all foodstuffs utilize environmental resources whose sustainability is crucial for food security. This analysis necessitates consideration of the basic concepts of sustainable development and food security, the strength of the link between these and differences in the patterns of sustainable management of agriculture, fisheries and aquaculture. The growing role of genetically engineered organisms has been included because of the immense possibilities these offer for maximizing food production despite the environmental and ethical concerns raised.
Biodynamics of water quality and related issues in integrated aquatic farming systems, especially the Integrated Multi-Trophic Aquaculture (IMTA), are reviewed in this paper. Combining several species in one system in addition to the microbiological organisms that become part of a production unit achieve biodynamics that is truly remarkable and mimics the processes that nature utilizes through biodiversity and interlinkages. Nutrient cascading is the most visible process in such a system. Some of the features that characterize IMTA include: harmonious functioning of multiple species, self-manuring, in tune with nature, wellbeing of captive stocks and low-carbon processes. Basically, IMTA has three loops: fed species and biofiltration, and the water quality impacted by processes in the first two loops. Maintaining homoeostasis in the system can be challenging for a number of reasons, including species-specific water quality requirements, turnover of dissolved gases (mainly oxygen and nitrogen) and particulate matter. Ammonia fluctuates with pH and temperature. Dissolved oxygen is influenced by temperature. While at neutral pH (7.0), more than 95% of ammonia is in ionized, non-toxic form (NH4+), the percentage of toxic un-ionized ammonia (NH3) increases with pH at a given temperature. NH3 is highly toxic. It produces stress at 0.1 mg/L by damaging the gills and disrupting metabolism, and death at higher concentrations. Nitrite is toxic when its concentration exceeds 0.4 mg/L. Concentration lower than this value can be fatal for more sensitive species. Process of nitrification that converts ammonia to nitrite and nitrite to nitrate requires at least 6 mg/L of dissolved oxygen. The culture system should remain well aerated, at slightly alkaline pH and moderately warm temperature, and must have substrate for nitrifying bacteria. Roles of the various types of filtering devices for organic and inorganic wastes are discussed in this paper.
Aquaculture has emerged as an important sector for addressing the challenge of global food security. In order for it to play this role, certain supporting policies and mechanisms are necessary. Because aquaculture is a subject where there is a convergence of science, art and business, this has a better chance of knowledge-based entrepreneurship. With the demand of seafood steadily rising, the market potential is high to strengthen the business activity related to aquaculture. Aquaculture can be conducted in a wide variety of aquatic environments, whether on land or in the sea, using different methods to produce many kinds of plants and animals for human consumption. This sort of diversity offers entrepreneurship of different types and scales. Not many subjects have as much advantages for entrepreneurship as aquaculture. Government demands that universities in Malaysia should impart entrepreneurship education to students and researchers to commercialize their findings. Aquaculture is one of the niche areas of Universiti Malaysia Sabah (UMS) and thus, it becomes a priority to implement the national policies pertaining to this sector. Steps taken by the University to demonstrate our response through specific case studies are explained in this paper. Borneo Marine Research Institute developed aquaculture as its flagship program of education and research. This included building of infrastructure and expertise. UMS is the only university in the country with two on-campus hatcheries (for finfish and shellfish) to offer education, training and research. Entrepreneurship is an integral part of the undergraduate program. Worthwhile research carried out yielded results of great significance in promoting aquaculture industry. Selection of need-based research topics and problem-solving approaches applied to produce tangible outcomes are highlighted here. The paper also elaborates what it takes to be an aquaculture entrepreneur and constraints of applying industrial model of aquaculture under the academic culture of institutions of higher education. It is evident from an in-depth analysis of the scenario that academic entrepreneurship requires a radical departure from the past practices and a paradigm shift to successfully unify the art, science and business of aquaculture to achieve seafood sustainability and security.
Stocking density can induce stress in fish in an aquaculture system if not handled properly, and the chronic stress may lead to mortality. Several studies have reported that the capability to deal with a range of stocking densities differs among fish species and maturity stage. Hence, fish larvae may have different resilience to stress from the adult fish. Milkfish larvae were reared in hatchery for 50 days using a recirculating culture system at four different stocking densities (8,12,16 and 20 larvae/liter). The growth performance was not significantly different (P>0.05) except at stocking density of 20 larvae/liter. The highest survival rate (88.04%) was recorded in the system with 8 larvae/liter while the lowest (55.44%) in the culture tank where stocking rate was 20 larvae/liter. The stocking density also influenced the RNA / DNA ratio of the milkfish larvae. The RNA/DNA ratio showed a pattern that was identical with that of sigmoid growth where stocking rate of 8, 12, and 16 larvae/liter gained weight until 30 days of rearing. Highest RNA/DNA ratio was recorded at 16 larvae/liter (2.85±0.004), while the lowest was at 20 larvae/liter (2.25±0.217). Food availability might play a limiting factor that leads to the lower RNA/DNA ratio of larvae reared at a high density due to competition.