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Food web architecture in natural and impounded rivers of the Upper Parana drainage basin, BrazilHoeinghaus, David Joseph 25 April 2007 (has links)
Freshwater ecosystems are some of the most threatened on the planet. Efforts to conserve, restore, or otherwise manage large rivers and the services they provide are hindered by limited understanding of the functional dynamics of these systems. This shortcoming is especially evident with regard to trophic structure and energy flow. In this study I use natural abundances of carbon and nitrogen isotopes to examine patterns of energy flow and food-chain length of large-river food webs characterized by different landscape-scale hydrologic features. Ten locations along an approximately 500 km stretch of the Upper Paraná River Basin, Brazil, provided the setting for this work. Carbon derived from C3 plants and phytoplankton were the dominant energy sources across all webs, but relative contributions differed among landscape types (low-gradient river, high-gradient river, river stretches downstream of reservoirs, and reservoirs). Increases in food chain length corresponded with higher relative importance of phytoplankton derived carbon, likely due to size-structured effects of the phytoplankton-zooplankton-secondary consumer trophic link. River impoundment corresponded with decreased ecological and economic efficiency of fisheries production, an important ecosystem service provided by many tropical rivers.
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Cold Chain management in food logistics : a multiple case study on food industryLi, Nanxi, Yang, Jin January 2013 (has links)
In current business global society, every food industry company is making efforts to provide high quality of products and satisfaction to customers. Balancing the low cost but with high efficiency when undertaking cold chain logistics becomes competitiveness in business market. This thesis is mainly to study cold chain management in food logistics by a multiple case study on food industry. The purpose of the paper is to advance the understanding of the cold chain management in food industry, aim to find how an efficient way to combine the logistics cost and the effectiveness of cold chain logistics and the challenges of the cold chain logistics in food industry. In this multiple case study, qualitative method was used to describe findings. The data collected can be divided into two types, the primary data and the secondary data. Primary data indicates the face-to-face interview with the managers and employees working for customer service in the selected companies. The secondary data are resources from archives, websites and other printed materials. To improve the validity, related literature were reviewed by authors to find the research questions. The reliability can be guaranteed because the theory part of the thesis abstracted from the publications, which have been approved for many years. The authors give the overview and practice in cold chain logistics of the three case companies, also mention the challenges both in developing and developed countries. The study finds the way to improve the utilization in cold chain logistics, fill the gap of logistics in food industry and give some advices for food industry.
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The feeding habits of bigeye tuna (Thunnus obesus) in the western Indian OceanLin, Jing-siang 11 September 2012 (has links)
The stomachs of 183 bigeye tuna (Thunnus obesus) were collected from three Taiwanese longline vessels operating in the western Indian Ocean during the period from April to December 2006. Their fork lengths ranged from 89 cm to 198 cm. Distinguishable prey species, belonging to 28 families, consisted mostly of fishes, crustaceans, and cephalopods. Fourteen prey items were newly recorded, among them, five families (Anoplogastridae, Bothidae, Grammicolepididae, Pinguipedidae, and Sciaenidae) were firstly recorded as the diet of bigeye tuna. Two special dietary species were found for the first time. Oplophorus gracilirostris, the dominant numerical dietary species, had not been previously recorded; however, O. typus had been recorded in the past. The other special prey species found, Macrurocyttus acanthopodus (Grammicolepididae), was not only the first record in the stomach of bigeye tuna but also the first record in the Indian Ocean. The largest body length among prey species was 655 mm for an Alepisaurus ferox. The number of prey species appeared to decrease with the increasing size of the bigeye tuna, and larger Indian bigeye tuna tended to feed on larger prey species. In the stomachs of the bigeye tuna, Oplophorus gracilirostris was the most frequently found prey species (56.8%). The three numerical most dominant prey species were Oplophorus gracilirostris (38.2%), Charybdis smithii (8.8%), and Alepisaurus ferox (3.6%). In addition, the fish prey item, Alepisaurus ferox, had the highest percentage of prey weight. The total percentage of prey weight for prey fishes is similar to that reported in previous research, but the average weight of Alepisaurus ferox is heavier than the previous report. Additionally, the percentage of prey weight for Paralepididae is lower than the results of previous studies. Moreover, the occurrence and percentage of the number of Oplophorus gracilirostris are distinctly higher than the results of previous studies. These findings indicate that the percentage of mean preys number exist seasonal effect. Alepisaurus ferox was the most numerous prey in May to July; Oplophorus gracilirostris was the most numerous prey at 200 m depth in August to October 45¢XE to east; Charybdis smithii was the most numerous prey at 50 m depth in August to October 45¢XE to west. A possible reason to explain this phenomenon is that there are strong feeding migratory behavior in bigeye tuna.
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Food web architecture in natural and impounded rivers of the Upper Parana drainage basin, BrazilHoeinghaus, David Joseph 25 April 2007 (has links)
Freshwater ecosystems are some of the most threatened on the planet. Efforts to conserve, restore, or otherwise manage large rivers and the services they provide are hindered by limited understanding of the functional dynamics of these systems. This shortcoming is especially evident with regard to trophic structure and energy flow. In this study I use natural abundances of carbon and nitrogen isotopes to examine patterns of energy flow and food-chain length of large-river food webs characterized by different landscape-scale hydrologic features. Ten locations along an approximately 500 km stretch of the Upper Paraná River Basin, Brazil, provided the setting for this work. Carbon derived from C3 plants and phytoplankton were the dominant energy sources across all webs, but relative contributions differed among landscape types (low-gradient river, high-gradient river, river stretches downstream of reservoirs, and reservoirs). Increases in food chain length corresponded with higher relative importance of phytoplankton derived carbon, likely due to size-structured effects of the phytoplankton-zooplankton-secondary consumer trophic link. River impoundment corresponded with decreased ecological and economic efficiency of fisheries production, an important ecosystem service provided by many tropical rivers.
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Metody stanovení radiologických dopadů v potravních řetězcích / Methods for the determination of radiological impact of the food chainsTesař, Jakub January 2011 (has links)
The diploma work presents comprehensive overview of methods of determination of radiological impact on food chains. It describes the determination of radionuclides in groceries in common radiation situation and in unusual radiation situation. Practical part of the work presents two model radiation events. These are radiation event in the territory of Czech Republic and radiation event in the territory of other country and its impact on Czech Republic. In the end both model situations are compared.
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Impacts of polyaromatic hydrocarbons (PAHs) on oligotrophic tropical marine organisms and food-chainsAshok, Ananya 04 1900 (has links)
Polyaromatic hydrocarbons (PAHs) are oil derived toxic and persistent pollutants prevalent across the oceans from pelagic waters to coral reefs. The Great Barrier Reef (GBR) in Australia and the Red Sea are important oligotrophic marine ecosystems susceptible to oil contamination. This Ph.D. dissertation aims to advance our understanding on PAH tolerance, accumulation dynamics and trophic transfer in oligotrophic ecosystems where those aspects remain poorly explored. In this dissertation, a new, highly-sensitive method combining stable carbon isotope labelling and cavity ring-down spectroscopy (CRDS) was developed to quantify PAH accumulation and applied in a series of ex situ food chain experiments with two representative PAHs, 13C-phenanthrene and 13C-pyrene. The experiments conducted with Acropora millepora – a common reef-building coral in the GBR, showed faster accumulation of both PAHs by dissolved uptake, although dietary exposure caused more consistent accumulation. Phenanthrene was not toxic to the coral photosystem II in either exposure mode but biomagnification increased with increasing food-chain complexity. In contrary, pyrene led to loss of symbionts accompanied by reduction in photosynthetic efficiency and coral bleaching, especially via dietary uptake. Also, microbial communities and food webs are relevant components of oligotrophic waters. We identified contrasting sensitivities among key autotrophic and heterotrophic microbial populations in the chronically oil exposed Red Sea to a mixture of 16 PAHs recognized as priority pollutants. The differential tolerance pointed towards localized selection for resistant strains in some populations. Some PAH toxicity thresholds approached ambient PAHs concentrations suggesting that any increase in pollution loads will hold consequences for these important microbial groups and their ecological functions.
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After the Aquaculture Bust: Impacts of the Globalized Food Chain on Poor Philippine Fishing HouseholdsMacabuac, Maria Cecilia Fiel 29 July 2005 (has links)
The Philippines is a food extractive enclave in the bust stage of export-oriented aquaculture, and this globalization agenda has had several negative impacts. Aquaculture has not expanded fish and marine foods but threatens national food security by integrating Philippine aquatic resources into the globalized food chain. Following structural adjustment policies imposed beginning in the 1980s, the Philippines shipped massive levels of animal protein to world markets, but this country has grown less food self-sufficient. During the decades that shrimp aquaculture has boomed and busted in the Philippines, the living conditions of Filipino families have steadily worsened. This study of three Panguil Bay fishing communities of Northern Mindanao demonstrates that the survival of subsistent artisan fisher households is now threatened because export-oriented producers have severely degraded the ecosystem upon which they rely. Moreover, women and children are inequitably threatened by the ecological and economic changes that have accompanied the Philippine global aquaculture agenda. In reality, capitalist commodity chains of export-oriented aquaculture externalize to households and to nature much of the true cost of producers and of ecological degradation. As a result, malnourished and impoverished Philippine fishing households subsidize global aquaculture commodity chains. While Filipino fisher households can no longer afford local food costs, their hidden inputs into capitalist commodity chains keep prices of luxury seafoods cheap in rich core countries. / Ph. D.
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Achieving health promoting gut microbiome modulation through sustainable, nutritious and healthy foods.Gaudioso, Giulia 25 February 2022 (has links)
The global pandemic of diet-related non-communicable diseases and the fact that global food production represents one of the largest contributors to greenhouse gas emissions, have identified unhealthy and unsustainably food chains as a major societal health challenge and a risk to ecosystem stability. This thesis aimed to investigate if digestion of nutritious, less highly processed foods could lead to health-promoting changes in the gut microbiota. Our modern Western-style diet (MWD) is characterized by high intake of extremely processed foods, which contain significant concentrations of inflammatory advanced glycation end-products (AGE) implicated in metabolic disease development. Novel observations in this thesis showed that chronic exposure to dietary AGE modulated gut microbiota (GM) community structure rendering it more similar to the GM previously observed in diabetic/obese mice. Further, I demonstrated that elevated systemic inflammatory markers could be mediated by AGE induced changes in GM composition. Measuring the potential of whole plant foods to improve gut health, a local broccoli ecotype (Broccolo of Torbole, BR) and Moringa oleifera were investigated using in vitro models of the human GM and intestinal epithelium. BR significantly reduced bacterial richness and evenness, increased Escherichia-Shigella relative abundance and decreased Alistipes and Ruminococcus 1. The GM extensively metabolized BR polyphenols and increased concentrations of short chain fatty acids. However, BR did not impact on intestinal permeability, using a Caco-2 monolayer model and trans-epithelial electrical resistance (TEER). This thesis provided novel insights on the fate of Moringa glucosinolates and polyphenols during faecal fermentation and on their potential beneficial activity on gut health, with glucomoringin significantly increasing TEER. Microbial communities are also involved in healthy and sustainable food production. Characterizing the successional development of local organic sauerkraut production, this thesis established a culture collection of sauerkraut lactic acid bacteria of potential future biotechnological evaluation and measured metabolite production during sauerkraut fermentation. Sauerkraut water improved immune response of a Caco-2-peripheral blood mononuclear cell (PBMC) in vitro model of the gut associated immune system upon inflammatory LPS challenge. Finally, since sustainable diets rely on sustainable and nutritious foods, I analyzed the role of the GM in improving the sustainability of farmed trout. Novel sustainable feeds containing poultry by-products (P) or insect protein (Hermetia illucens (H) meal), were investigated for their potential impact on fish growth performance, GM composition and inflammatory biomarkers. P increased the relative abundance of protein-degraders Paeniclostridium and Bacteroidales, while H increased chitin-degraders Actinomyces and Bacillus. This study also provided evidence of feed-chain microbiome transmission of Actinomyces from insect H feed to trout GM. The analysis of gut microbiomes therefore represents an innovative strategy to define healthy reference diets, to characterize the potential health effects of local and traditionally produced foods, to identify new sustainable and nutritious crops, and to drive the urgently needed transformation of the global food system. In order to obtain more sustainable, healthy and nutritious food production systems a better understanding and management of microbiomes along the food chain has never been more important.
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Brödsvinn i livsmedelskedjan : En studie om matsvinn med fokus på butiksledet / Waste of bread in the food chain : A study on food waste with focus on the store levelSorte, Christian, Holmström, Simon January 2020 (has links)
Detta är en rapport om svinn av bake-off bröd i butiksledet i Sverige och hur det kan begrän- sas. Vald metod består av två delar. Den första delen är en litteraturstudie om matsvinn. Den andra delen består av intervjuer med en chef på utvald livsmedelsbutik angående svinn av bröd. Orsakerna och åtgärderna jämförs med situationen i den undersökta butiken och åtgär- derna analyseras utifrån tillämpbarhet. Resultatet visar att det finns kundrelaterade och butiks- relaterade orsaker. Kunden förväntar sig ett brett sortiment och välfyllda hyllor. I dagsläget finns en god vetskap om denna typ av problem som påverkas av kunden. Svinn uppstår när den undersökta butiken köper in fel mängd varor. Denna orsak förklarar tydligt vad felet är, vilket inte alltid är fallet med orsaker funna i litteraturstudien. Det är viktigt att analysera hur olika orsaker hänger samman och poängtera den verkliga orsaken till problemet om det ska åtgärdas. Att implementera strikta rutiner för att minska svinn är upp till butiken och förbätt- rar presentationen i butiken. Sådana tillämpbara åtgärder karakteriseras av att vara ekono- miskt fördelaktiga eller att införandet ligger i butikens händer. Butiksansvarig kan informera personalen om ekonomiska och miljömässiga konsekvenser av svinn. Kunderna är däremot omedvetna om att de kan påverka matsvinn redan i butiken och initiativ från högre instanser krävs för att minska denna typ av svinn. / This report highlights the waste of bake-off bread occurring at the store level in Sweden and possible ways of preventing it. The method in the report consists of two parts. Firstly, a litera- ture review of earlier studies on food waste. Secondly, interviews with the manager of a selec- ted grocery store regarding the waste of bread. The causes of food waste, and the measures for reducing it, are compared with the situation in the interviewed store. Furthermore, the measu- res are analyzed based on applicability. The causes either relate to consumers or actions made by the store. Consumers expect the shelves to be fully stocked and products to be widely vari- ed. There is currently a thorough understanding of this sort of problem relating to the consu- mer. Food waste occurs when the store buys the wrong amount of goods. This sentence clear- ly explains what needs to be changed to prevent waste. However, this is not always the case with the causes explained in earlier studies. To prevent food waste, connections between cau- ses must be analyzed and the precise cause of the food waste must be determined. To imple- ment strict routines to reduce waste or not depends solely on the store’s preference. The im- plementation furthermore improves the presentation of the store. These applicable measures to reduce food waste are defined by being profitable or being implementations on the store’s terms. The store manager can inform the staff about the financial and environmental conse- quences of food waste. Consumers, however, are unaware that they can have an impact on food waste already in the store. Therefore, initiatives from higher authorities are necessary to reduce this form of waste.
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LIGHT, NUTRIENT, AND PLANKTIVORY EFFECTS ON ZOOPLANKTON COMMUNITIES AND FOOD CHAIN EFFICIENCYBobson, Jennifer 27 November 2007 (has links)
No description available.
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