In 2003, seeds of Macrobrachium rosenbergii were stocked at 2, 4, and 6 postlarvae/m2 as well as 1, 2 and 3 juveniles/m2 with two culture systems, the integrated and rotational prawn - rice systems. Prawns were fed with pellets twice a day. Water levels in rice plots were arranged at the same levels for both systems. The dissolved oxygen concentrations in the integrated system were lower than in the rotational system. The growth of prawns decreased at higher stocking densities. Prawns in the rotational system grew faster than those in integrated system. The yields ranged from 286 ± 32 to 516 ± 51 and 412 ± 17 to 584 ± 37 kg/ha in the integrated and rotational system at stocking PL, respectively. The yields of prawns ranged from 251 ± 16 to 430 ± 54 and 297 ± 24 to 486 ± 38 kg/ha in integrated and rotational prawn - rice systems stocking juveniles, respectively. However, at higher density, the investment cost significantly increased (P < 0.05), while profit significantly decreased (P < 0.05). At low density, cost benefit ratio and profit were the highest (P < 0.05). Finally, the integrated rice - prawn system gives lower profits than the rotational system. In 2004, an experiment on the effects of stocking densities (1, 2, 3 and 4 PL/m2) and feeding types, pellets only (P) and pellets + snail meat (PS), on the production and economic aspects of rotational prawn culture in the rice fields were carried out in the same culture facilities. Water levels were 0.3 - 0.6 m in rice-grown areas. Water temperatures were higher than the suitable range for prawns at noon in the hot months. After 7 months, survival rates of prawns were 28.0 - 50.3 %. Final mean weights were 32.0 - 39.8 g/prawn. Yields ranged from 194 ± 82 to 373 ± 32 kg/ha. There was no significant difference between the two types of feeding on production parameters (P > 0.05). The total cost significantly increased at higher densities (P < 0.05) but it was not different between feed types (P > 0.05). Net profit and cost benefit ratio of treatment PS were significantly higher than in treatment P. In the present study, yield (394 ± 22 kg/ha) and cost benefit ratio (1.57 ± 0.07) in treatment PS at 3 PL/m² were significantly the highest (P < 0.05). The effects of stocking densities of postlarvae (0.5, 1 and 2 PL/m2) on the production and economics of prawn culture in the integrated rice - prawn system were studied to affirm the efficiency of this model with low investment. The high temperature in the dry season and low dissolved oxygen after rice harvesting caused small final mean weights, low survival rates and low yields. However, low investment in this system led to good cost benefit ratio. The on farm trials of rotational rice - prawn farming in the semi-deep water area were monitored with the farmers in six rice fields (0.7 - 1.0 ha). Two treatments of feed types (pellets and pellets + snail meat) were applied at stocking 4 PL/m2. Prawns in two treatments of densities (4 and 5 PL/m2) were fed on a combination of pellets and snail meat. By cull harvesting during the culture period, final mean weights of prawn were improved and larger than 50 g/prawn in all treatments. The prawn yield of treatment 5 PL/m2 was highest (630 ± 22 kg/ha). Net profits in the treatment using a combination of pellets and snail meat were 861 ± 193 US$/ha to 1,019 ± 25 US$/ha for the prawn crop and 1,393 ± 71 US$/ha to 1,576 ± 180 US$/ha for the whole system (prawn crop + dry rice crop). The integrated two rice crop and one prawn crop system with low investment costs can be applied by poor farmers, while the rotational a rice crop and one prawn crop system with higher operating costs can be practiced by moderately well off and rich farmers. Due to a higher economic return than monoculture of rice or rice - fish systems, rice - freshwater prawn system is spreading very rapidly in the Mekong Delta of Vietnam. En 2003, de jeunes Macrobrachium rosenbergii furent stockés à 2, 4 et 6 postlarves/m² ainsi qu’à 1, 2 et 3 juvéniles/m² dans deux systèmes de culture: riz et crevettes produits soit en même temps (intégration) soit successivement (rotation). Les crevettes étaient alimentées de granulés deux fois par jour. Les niveaux d’eau dans les casiers rizicoles ont été maintenus identiques dans les 2 systèmes. Les concentrations en oxygène dissous dans le système intégré étaient plus faibles que dans le système en rotation. La croissance des crevettes a diminué aux plus fortes densités. Les crevettes dans le système en rotation ont grandi plus rapidement que dans le système intégré. Les récoltes à partir de postlarves se sont étalées de 286 ± 32 à 516 ± 51 et de 412 ± 17 à 584 ± 37 kg/ha respectivement dans le système intégré et en rotation. Les récoltes à partir de juvéniles se sont étalées de 251 ± 16 à 430 ± 54 et de 297 ± 24 à 486 ± 36 kg/ha respectivement dans le système intégré et en rotation. Cependant, à plus forte densité, les coûts d’investissement augmentent significativement (P < 0,05), tandis que le profit diminue significativement (P < 0,05). A faible densité le rapport coûtbénéfice et le profit ont été les plus élevés (P < 0,05). Finalement, le système intégré riz-crevette donne des profits plus faibles que le système en rotation. En 2004, une expérience sur les effets de différentes densités de mise en charge (1, 2, 3 et 4 PL/m²) et des types d’aliments, granulés uniquement (G) ou granulés et viande d’escargot (GE), sur la production et les aspects économiques de la culture riz-crevette en rotation ont été effectués dans les mêmes installations que précédemment. Les niveaux d’eau ont varié de 0,3 à 0,6 m dans les zones de production du riz. Les températures de l’eau ont été plus élevées que la température optimale pour la crevette du moins à midi pendant les mois les plus chauds. Après 7 mois, les taux de survie ont été de 28,0 à 50,3 %. Les poids moyens finaux étaient de 32,0 à 39,8 g/crevette. Les récoltes s’étalaient entre 194 ± 82 à 373 ±32 kg/ha. Aucune différence statistique (P < 0,05) concernant les paramètres de production n’a été enregistrée entre les deux types d’alimentation. Les coûts totaux ont augmenté significativement (P < 0,05) à plus fortes densités de mise en charge mais n’étaient pas différents selon les types d’aliments. Le profit net et le rapport coût bénéfice ont été significativement plus élevés avec les aliments combinés (GE) qu’avec les granulés seuls (G). Nos travaux démontrent que la récolte (394 ± 22 kg/ha) et le rapport coût bénéfice du traitement aliment combiné (GE) à 3 PL/:m² donne les meilleurs résultats (P < 0,05). Les effets de différentes densités de mise en charge de postlarves (0,5, 1 et 2 PL/m²) sur la production et le gain monétaire de l’élevage de crevette d’eau douce dans le système riz –crevette intégré ont été étudiés afin de confirmer l’efficacité de ce modèle basé sur un faible investissement. La température élevée en saison sèche et les faibles concentrations en oxygène dissous de l’eau après la récolte du riz induisent des poids moyens finaux faibles, de faibles taux de survie et de faibles récoltes. Cependant, le faible investissement nécessaire conduit à un bon rapport coût bénéfice. Les essais sur fermes du système riz-crevette en rotation dans les zones semi-profondes du district de Codo ont été effectués de façon participative avec les fermiers dans six champs de riz (0,7-1,0 ha). Deux types d’aliments (G et GE) ont été testés à la densité de 4 PL/m² et deux types de densité (4 et 5 PL/m²) ont été testés avec l’aliment combiné (GE). Grâce à des récoltes partielles en cours de production, les poids moyens finaux des crevettes ont été améliorés et étaient supérieurs à 50 g/crevette pour tous les traitements. La récolte de crevette à 5 PL/m² a été la plus élevée (630 ± 22 kg/ha). Les profits nets du traitement combinant les 2 types d’aliments (GE) ont varié de 861 ± 193 US$/ha à 1.019 ± 25 US$/ha pour la récolte de crevettes et de 1.393 ± 71 US$/ha à 1.576 ± 180 US$/ha pour l’ensemble du système (riz + crevette). Le système intégré de deux récoltes de riz et 1 récolte de crevette par an nécessite peu d’investissement et peut être appliquée par les fermiers les plus pauvres tandis que le système une récolte de riz et une récolte de crevette en rotation par an nécessite des investissements plus conséquents et ne peut être appliqué que par des fermiers aisés ou riches. Etant donné que le revenu économique du système riz-crevette est nettement plus élevé que la seule riziculture ou même que la rizipisciculture, ce système est en train de se développer très rapidement dans le delta du Mékong.

The variation of the composition of assemblages and the relative abundance of commercial prawns collected from the coastal waters of Yunlin was studied. The data of shrimp fishery was collected from Jan 1997 to Dec 2008 through the program of Integrated Assessment and Management of Environmental Resources for the Industrial District on the Outer-Bank of Yunlin Islands. The dominant species landed in this area are Parapenaeopsis hardwickii, Metapenaeus ensis, and Penaeus penicillatus. Their peak catch seasons are November to May, March to August, and July to March, respectively. The composition of the assemblages of commercial shrimps belonged to three groups according to the seasons: winter (December to February), spring to summer (March to July), and late summer to autumn (August to November). According to time series analysis, the relative abundance is auto-regressed to that of the previous month and the same month one year age. In addition, Jhuo-Shuei river runoff ware correlated to a significant decrease of the shrimp abundance five months later. Based on this information, we obtained a seasonal and factored ARIMA time series equation of the relative abundance of commercial shrimps.

Increased international trade has sparked a debate on the need to coordinate dispersedactivities in Global Value Chains, linking production to end consumers. Implementationof standards has in the literature on Global Value Chains been suggested as a wayto coordinate a value chain. We have investigated the value chain of shrimp andprawns production in Bangladesh, in order to analyze if standards placed by the EUhave proven a successful way to coordinate the value chain. The implementation ofstandards has been studied to capture the coordination in the value chain. A singlecase study was conducted with interviews from a sample of actors in direct or closeconnection to the production of shrimp and prawns in Bangladesh. The focus of thestudy has been on the perspectives of the individuals and if and how standards areimplemented successfully in a social context. The attempt has been to bridgeunderstandings of implementation of standards together with knowledge of the complexnature of Global Value Chains. The results show that there are multiple challengesto successful implementation of standards. Hurdles can especially be linked tothe ability to follow standards where lack of human- and financial resources havebeen found. In addition, the will to follow standards can have an impact when traditionalmethods stand in the way and immediate financial incentives are not in place.

Many brackish water aquaculture ventures in Australia and overseas have established ponds in coastal regions with acid sulfate soils (ASS). Acid sulphate soils are known to leach relatively high concentrations of metals, acid (metal and H+ ion) and sulfur, however very little is known about how these leached elements affect the water quality of aquaculture ponds. The main objective of this thesis was to describe the hydrochemical processes controlling the water chemistry in the water column and sediment pore water in the studied aquaculture ponds over time and space. Water samples providing the spatio-temporal data were collected from the ponds with the use of adapted sampling methods commonly used in the groundwater environment. A transect of five nested piesometers was installed in two prawn ponds at Pimpama, south east Queensland, Australia. Each piesometer nest contained a multilevel with eight outtakes, a mini ?? horizontal, and a slotted piesometer. Water samples were collected from each nested piesometer on a bi-monthly basis over the prawn-growing season. The unstable elements and water quality variables (pH, Eh, DO, EC, water temperature) were measured in the field. Stable elements were analysed in the laboratory using ICP-OES and ICP-MS. Soil samples were collected at the end of the season for elemental analysis. A number of key sediment/water interactions and processes such as precipitation/dissolution reactions, oxidation-reduction reactions, photosynthesis, adsorption and seawater buffering were identified as important controls on pond water conditions. This is the first study to provide detailed hydrochemcial analysis of the pond water over time and space and aided in identifying that even shallow water bodies can be chemically heterogeneous. Analysis of the water and sediment highlighted the selection of metals that can be associated with ASS and that are mobilised from pond sediments under certain chemical conditions. In Pond 7 Al, As, Ni and Zn concentrations were generally higher at the beginning of the grow-out season. Variability of the metal concentration was observed between the water column (0 ?? 1500 mm) and the pore-water (0 - -1000 mm). The highest concentration of Al (1044 ??g/L) and Zn (104 ??g/L) were sampled in the water column (approximately 400 mm from the surface of the pond). The highest concentration of As (130 ??g/L) and Ni (73 ??g/L) were sampled in the pore water sediment (associated with ASS). Elevated Mn and Fe2+ concentrations were also associated with the sediment pore water. The highest concentrations of Mn and Fe2+ were 4717 ??g/L and 5100 ??g/L respectively. In Pond 10, Ni concentrations (167 ??g/L) were the highest at the beginning of the grow-out season. However, As (97 ??g/L), Al (234 ??g/L) and Zn (308 ??g/L) were most concentrated during the middle of the cycle. The highest mean concentrations of these elements are As (63 ??g/L), Al (91 ??g/L) and Zn (69 ??g/L) which are each associated with the sediment-water interface. These metals are integral in degrading the pond water quality and lead to a loss of beneficial algal blooms, a reduction in pond water pH, poor growth rates and high mortality in shrimp. It is also possible that the dissolved ions and precipitated compounds that are leached from the ASS are discharged into the adjacent coastal estuary of Moreton Bay. With knowledge obtained from this PhD study, effective management and treatment systems can be developed and implemented to minimise the impact of these soils on the pond system and the water discharging into natural coastal ecosystem.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 4 uppsatser.

Thesis (MSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Comparative analyses of genetic diversity, population structure and evolutionary relationships among co–distributed species can provide useful insights into fisheries management. In this study, mitochondrial DNA control region (mtCR) sequences were used to investigate genetic population structure and recruitment patterns of three co–occurring shallow water penaeid prawn species; Penaeus monodon, Fenneropenaeus indicus and Metapenaeus monoceros. These taxa dominate artisanal and commercial prawn catches in the Malindi–Ungwana Bay in Kenya, where juvenile prawns inhabit estuarine habitats, and adults occur further offshore, on mudbanks in the bay. A total of 296 [i.e. (P. monodon; n = 129), (F. indicus; n = 96), (M. monoceros; n = 71)] specimens were sampled from five sites; two estuarine nursery areas (juveniles), a nearshore mid–station (adults), and two offshore areas (adults). The sites were chosen to represent the bulk of the Kenyan fishery activities, and to include juvenile and adult cohorts that are presumably connected to each other through larval dispersal processes and migrations. Juveniles were obtained during 2010 from local fishermen, and adult prawns during 2011 using a commercial prawn trawler. Analysis of the mtCR sequences indicated high haplotype diversity (P. monodon; h = 0.9996 ± 0.0010; F. indicus; h = 0.9998 ± 0.0015; M. monoceros; h = 0.9815 ± 0.0110) for all three species. Genetic differentiation results for each species using AMOVA indicated no significant population differentiation (P. monodon; ΦST = 0.000, = p > 0.05; F. indicus; ΦST = 0.000, = p > 0.05; M. monoceros; ΦST = 0.0164, = p > 0.05) and pairwise ΦST statistics among sampling sites indicated the complete absence of spatial differentiation of female genes for all three species. In addition, the mtDNA data of P. monodon (i.e. n = 103) was augmented by using six polymorphic nuclear microsatellite loci. The pattern of panmixia was supported by the microsatellite analyses of P. monodon where AMOVA (i.e. RST = 0.00113, = p > 0.05), pairwise RST statistics (i.e. RST = 0.0000–0.0223, = p > 0.05) and STRUCTURE all confirmed the complete absence of genetic differentiation, among all sampled localities. Based on the absence of genetic population structure, each of the three species can be regarded as a single management unit throughout the Malindi–Ungwana Bay area. Spatial management strategies for prawn fisheries in the bay should therefore rely on factors other than genetic metapopulations, such as seasonal prawn recruitment and distribution patterns, ecosystem functioning and socio–economic implications to fishing communities and commercial trawl fishing companies. / AFRIKAANSE OPSOMMING: Vergelykende analise van genetiese diversiteit, bevolkings stuktuur en evolutionêre verwantskappe tussen spesies wat 'n verspreidingsgebied deel kan nuttige insigte lewer oor vissery bestuur. In hierdie studie was die mitokondriale DNS kontrole area (mtCR) volgordebepalings gebruik om die bevolkings genetiese stuktuur en werwingspatrone van drie mede-verspreide vlak water penaeid garnaal spesies; Penaeus monodon, Fenneropenaeus indicus and Metapenaeus monoceros te ondersoek. Hierdie taksa domineer die ambagtelike en kommersiële vangste in die Malindi-Ungwanabaai in Kenya waar, onvolwasse garnale in riviermondings voorkom en volwassenes in dieper waters op modderbanke in die baai voorkom. 'n Totaal van 296 [(P. monodon; n = 129), (F. indicus; n = 96), (M. monoceros; n = 71)] monsters was geneem vanaf vyf lokaliteite; twee in riviermondings (onvolwassenes), 'n nabykus mid stasie (volwasse) en twee diep water (volwasse) areas. Hierdie lokaliteite was gekies om die oorgrote meerderheid van Kenya se vissery aktiwiteite, asook die onvolwasses en volwassene kohorte te verteenwoordig wat vermoedelik geneties verbind is aan mekaar deur larwale verspreidingsprosesse en migrasies. Onvolwasse diere was verkry in 2010 vanaf plaaslike vissermanne en volwasse diere was in 2011 gekollekteer deur gebruik te maak van 'n kommersiële garnaal vissersboot. Analise van die mtCR volgorde bepaling het gewys dat daar 'n hoë haplotipiese diversiteit (P. monodon; h = 0.9996 ± 0.0010; F. indicus; h = 0.9998 ± 0.0015; M. monoceros; h = 0.9815 ± 0.0110) vir al drie spesies bestaan. Genetiese differensiasie resultate vir elke spesie, bepaal deur 'n AMOVA toets, dui op geen beduidende bevolking differensiasie nie (P. monodon; ΦST = 0.000, = p > 0.05; F. indicus; ΦST = 0.000, = p > 0.05; M. monoceros; ΦST = 0.0164, = p > 0.05) en paarsgewyse ΦST statistiek tussen die lokaliteite waar monsters geneem was, dui op geen ruimtelike differensiasie van die vroulike gene in al drie spesies nie. Hierbenewens is die mtDNS datastel van P. monodon (i.e. n = 103) uitgebrei deur ses polimorfiese kern mikrosatelliete in te sluit. Die patroon van mtCR panmixia was ondersteun deur die mikro-satelliet analise van P. monodon waar die AMOVA (i.e. RST = 0.00113, = p > 0.05), paarsgewyse RST statistiek (i.e. RST = 0.0000-0.0223, = p > 0.05) en STRUCTURE bevestig het dat daar totale afwesigheid is van genetiese differensiasie tussen alle vergelyk-te lokaliteite. Gebaseer op die afwesigheid van genetiese bevolking-struktuur kan elk van die drie spesies beskou word as 'n enkele bestuurseenheid deur die Malindi-Ungwanabaai area. Die bestuurstrategieë vir garnaal vissery aktiwiteite in die baai moet dus steun op ander faktore as genetiese meta-bevolking. Belangrike faktore om in ag te neem is seisoenale garnaal werwing en verspreidings patrone, ekosisteem funksionering en sosio-ekonomiese implikasies van vissers gemeenskappe en kommersiële visserymaatskappye.

Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-08-31T15:22:10Z No. of bitstreams: 1 VERSÃO FINAL DA DISSERTAÇÃO DE MESTRADO - RAFAEL DOURADO PIMENTA FONTES.pdf: 2834377 bytes, checksum: 4df31943280d22c5475b7e744e8d6683 (MD5) / Approved for entry into archive by Vanessa Reis (vanessa.jamile@ufba.br) on 2016-09-02T16:18:17Z (GMT) No. of bitstreams: 1 VERSÃO FINAL DA DISSERTAÇÃO DE MESTRADO - RAFAEL DOURADO PIMENTA FONTES.pdf: 2834377 bytes, checksum: 4df31943280d22c5475b7e744e8d6683 (MD5) / Made available in DSpace on 2016-09-02T16:18:17Z (GMT). No. of bitstreams: 1 VERSÃO FINAL DA DISSERTAÇÃO DE MESTRADO - RAFAEL DOURADO PIMENTA FONTES.pdf: 2834377 bytes, checksum: 4df31943280d22c5475b7e744e8d6683 (MD5) / CNPq e FAPESB / Na atualidade, o consumo de organismos marinhos (principalmente peixes e camarões) tem aumentado cada vez mais, devido à sua constituição proteica. Nos últimos anos, com a elevada demanda de pescados, intensificou-se também o cultivo (aquicultura), principalmente de camarão, para suprir o mercado consumidor. A aceitação de alimentos de origem marinha pelo consumidor está diretamente relacionada ao odor e sabor que devem ser atrativos e agradáveis. As principais substâncias químicas identificadas com as responsáveis pelo “flavor” dos alimentos marinhos são os bromofenóis simples 2-bromofenol (2-BF), 4-bromofenol (4-BF), 2,4-dibromofenol (2,4-DBF), 2,6-dibromofenol (2,6-DBF) e 2,4,6-tribromofenol (2,4,6-TBF). A microextração com gota única (SDME) é uma técnica que apresenta muitas vantagens, quando comparada com as técnicas clássicas, pois permite o isolamento e pré-concentração dos analitos em um passo único, seguida de introdução da amostra em sistema de análise por CG-EM. Esta técnica vem ganhando destaque por não ser exaustiva, utilizar uma quantidade muito pequena de solvente (estando de acordo com os preceitos da química verde), requer um curto tempo de análise, tem elevada sensibilidade e baixo custo. Nesse trabalho foi desenvolvida uma nova metodologia analítica baseada em SDME e CG-EM para determinação de bromofenóis em abdômen e ração de camarão cultivado (carcinicultura) (Lithopenaeus vannamei) e abdômen de camarão pescado (Xiphopenaeus kroyeri, camarão sete barbas) em diferentes estações do ano. A otimização da técnica por CG-EM permitiu boa separação dos bromofenóis simples em apenas 15 minutos. Esta nova metodologia foi validada em função da linearidade das curvas analíticas, limite de detecção e quantificação, precisão e recuperação para cada um dos cinco analitos estudados. A recuperação e precisão variaram, respectivamente, de 50,8 a 103% e de 2,27 a 18,8%. Os limites de detecção e quantificação variaram, respectivamente, de 0,200 a 0,499 ng mL-1 e de 0,500 a 1,000 ng mL-1. Não foi perceptível uma relação regular ou linear entre a sazonalidade e a concentração dos bromofenóis nos camarões pescados. Tanto na primavera quanto no verão a maior concentração detectada foi do 2,4-DBF, enquanto no outono e inverno foram o 4-BF e o 2-BF respectivamente. Já no abdômen do camarão de cativeiro e na ração deste a maior concentração foi do 4-BF. A menor concentração na ração, no abdômen do camarão cultivado e na estação verão corresponde ao 2-BF, na primavera e no outono ao 2,6-DBF, enquanto no inverno ao 4-BF. A metodologia desenvolvida, além de apresentar baixos limites de detecção e quantificação, envolve menor tempo de análise, menor consumo de energia e solventes, sendo assim compatível com os preceitos da Química Verde. / At present, the consumption of marine organisms (mainly fish and shrimp) has increased even more, due to its constitution protein. In recent years, with the high demand of fish, also accelerated cultivation (aquaculture), especially shrimp, to supply the consumer market. Acceptance of marine foods by consumers is directly related to odor and flavor that should be attractive and pleasant. The main chemicals identified as responsible for the "flavor" of marine foods are simple bromophenol 2-bromophenol (2-BF), 4-bromophenol (4-BF), 2,4-dibromophenol (2,4-DBF) 2,6-dibromophenol (2,6-DBF) and 2,4,6-tribromophenol (2,4,6-TBF). A single droplet with microextraction (SDME) is a technique that has many advantages compared with conventional techniques, since it allows the isolation and preconcentration of analytes in a single step, followed by introduction of the sample analysis system GC-MS. This technique has been gaining attention for not being exhaustive, use a very small amount of solvent (which is consistent with the principles of green chemistry), requires a short analysis time, has high sensitivity and low cost. In this work we developed a new analytical methodology based SDME and GC-MS to determine bromophenols in abdomen and feed farmed shrimp (Lithopenaeus vannamei) shrimp fished and abdomen (Xiphopenaeus kroyeri, seven shrimp whiskers) in different seasons year. Optimization of GC-MS technique allowed good separation of bromophenols simple in just 15 minutes. This new methodology was validated on the basis of the calibration curves linearity, limit of detection and quantification accuracy and recovery for each of the five analytes studied. The recovery and precision ranging, respectively, from 50,8 to 103% and from 2,27 to 18,8%. The limits of detection and quantification varied, respectively, from 0,200 to 0,499 ng ml-1 and 0,500 to 1,000 ng ml-1. It was not noticeable or a regular relationship between the linear and the concentration of bromophenol seasonality in shrimp fished. Both in spring and in summer the highest concentration detected was 2,4-DBF, while in autumn and winter were the 4-BF and 2-BF respectively. Already in the abdomen of shrimp feed in captivity and this was the highest concentration of 4-BF. The lowest concentration in the feed, abdomen farmed shrimp and summer season match 2-BF, in spring and autumn to 2,6-DBF, while in winter the 4-BF. The methodology developed, and have low limits of detection and quantification, involves less analysis time, lower power consumption and solvents and is therefore compatible with the principles of Green Chemistry

En los últimos diez años, el Perú ha mostrado un crecimiento en las exportaciones de langostinos congelados desde la región de Tumbes con destino a Estados Unidos, esta investigación analiza las variables que influyeron en dichas exportaciones bajo el contexto del APC Perú- Estados Unidos. Las variables que se analizan son las medidas sanitarias, precio FOB y aranceles. La industria acuícola ha ido ganando mayor participación en el conjunto de actividades económicas en el Perú, siendo sus principales mercados destino Estados Unidos, España y Canadá. Esta actividad se ha visto favorecida por el APC Perú- EE.UU., ya que en este se trataron y suprimieron temas relacionados a barreras arancelarias y no arancelarias. La exportación de langostinos congelados peruanos ha presentado fluctuaciones en los últimos años debido a las variaciones en el precio internacional, variable que afecta directamente a los productores acuícolas pues impacta en la cantidad exportada tanto en volumen como en valor FOB, aplicación de medidas sanitarias estadounidenses y la desgravación arancelaria que nació con el TLC. Esta investigación propone que las exportaciones peruanas de colas de langostinos congelados se ven influenciadas por el precio FOB, la desgravación arancelaria y las medidas sanitarias. Estas variables fueron analizadas bajo un enfoque mixto que combina la investigación cualitativa y cuantitativa. En cuanto a lo cualitativo, se realizaron entrevistas a especialistas y expertos en la materia y la información obtenida se procesó en Atlas.ti para identificar los puntos más relevantes. En cuanto a lo cuantitativo, se tomó data histórica de fuentes secundarias confiables, las cuales fueron analizadas en el programa SPSS bajo regresión lineal y con ello se validó que, entre otros resultados, el R2 ajustado demuestra que existe un alto grado de correlación entre la variable dependiente y las variables independientes. En síntesis, las variables precio, medidas sanitarias y desgravación arancelaria sí influyen en las exportaciones de cola de langostinos congelados del departamento de Tumbes a Estados Unidos, ya que, en la investigación cualitativa basada en entrevistas, los expertos coincidieron en que las variables son influyentes, al igual que en el análisis estadístico donde el R2 para la regresión lineal fue optimista, reflejando una estimación certera. / In the last ten years, Peru has shown growth in exports of frozen prawns from the Tumbes region to the United States, this research analyzes the variables that influenced these exports under the context of the Peru-United States APC. The variables analyzed are the sanitary measures, FOB price and tariffs. The aquaculture industry has been gaining greater participation in the set of economic activities in Peru, with its main destination markets being the United States, Spain and Canada. This activity has been favored by the Peru-US APC, since this topic dealt with and suppressed issues related to tariff and non-tariff barriers. The export of frozen Peruvian prawns has fluctuated in recent years due to variations in the international price, a variable that directly affects aquaculture producers as it impacts the quantity exported both in volume and FOB value, application of US sanitary measures and the tariff reduction that was born with the FTA. This research proposes that Peruvian exports of frozen shrimp tails are influenced by the FOB price, the tariff reduction and the sanitary measures. These variables were analyzed under a mixed approach that combines qualitative and quantitative research. Regarding the qualitative, interviews were conducted with specialists and experts in the field and the information obtained was processed in Atlas.ti to identify the most relevant points. Regarding the quantitative, historical data was taken from reliable secondary sources, which were analyzed in the SPSS program under linear regression and with this it was validated that, among other results, the adjusted R2 shows that there is a high degree of correlation between the dependent variable and independent variables. In summary, the variables price, sanitary measures and tariff reduction do influence the exports of frozen shrimp tail from the department of Tumbes to the United States, since, in the qualitative research based on interviews, the experts agreed that the variables are influential , as in the statistical analysis where the R2 for the linear regression was optimistic, reflecting an accurate estimate. / Tesis