• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 4
  • 1
  • Tagged with
  • 5
  • 5
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Deforestation and Local Livelihood Strategy: A Case of Encroachment into the Wunbaik Reserved Mangrove Forest, Myanmar / 森林消失と地域住民の生業戦略:ミャンマー・ウンバイク・マングローブ保全林への侵入事例

Aye, Aye Saw 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第20448号 / 農博第2233号 / 新制||農||1050(附属図書館) / 学位論文||H29||N5069(農学部図書室) / 京都大学大学院農学研究科森林科学専攻 / (主査)教授 神﨑 護, 教授 北島 薫, 教授 柴田 昌三 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM
2

Autonomous water-cleaning machine using solar energy in shrimp ponds / Nghiên cứu, phát triển thiết bị tự hành làm sạch nước trong vuông tôm sử dụng năng lượng mặt trời

Dang, Thien Ngon 14 November 2012 (has links) (PDF)
Limited water exchange shrimp culture technology is commonly used today in many shrimp farms in Vietnam to reduce water usage, input of diseases and discharge of nutrient-rich effluents into environment as well as to increase the production per unit area. However, a remaining problem in this technology is that the water quality in shrimp ponds will be reduced due to limitation of water exchange for a long period. The accumulation of inorganic components such as waste feed, bacterial deposits or other biological debris at the pond bottom will lead to low dissolved oxygen, high ammonia-nitrogen level, high fecal coliform bacteria and high turbidity which cause a severe degradation of water quality and detriment to shrimp growth and survival. To solve this remaining problem, an autonomous water-cleaning machine for shrimp ponds was designed to control the waste accumulation in the pond. This is an effective solution to replace manual cleaning methods for water quality management in shrimp farming in the coastal area of the Mekong delta of Vietnam. Especially, this technique can be used for biosecure shrimp production systems according to GMP standards to meet the objectives for sustainable development of shrimp aquaculture in Vietnam. / Kỹ thuật nuôi tôm không thay nước đang được sử dụng rộng rãi ở các trại nuôi tôm Việt Nam vì giúp giảm lượng nước sử dụng, hạn chế thải nước vào môi trường và giúp tăng diện tích nuôi trồng tôm. Tuy nhiên, bản thân kỹ thuật này cũng tạo nên một sản phẩm chất thải là phân tôm, thức ăn và chế phẩm sinh học xử lý nước dư thừa. Chất thải này dần dần tích tụ dưới đáy ao tạo thành lớp bùn độc, rất thiếu ôxy và chứa nhiều chất gây hại như ammonia, nitrite, hydrogen sulfide. Để tránh làm giảm diện tích ao nuôi do chất thải tích tụ làm tôm lảng tránh và tăng mật độ tôm nuôi trồng, thiết bị tự hành thu gom chất thải làm sạch nước trong vuông nuôi tôm đã được nghiên cứu, thiết kế và chế tạo thành công. Thiết bị đã thay thế các hoạt động làm sạch chất thải thủ công của con người, không sử dụng các nguồn năng lượng gây ô nhiễm, giảm nhu cầu về điện góp phần phát triển sản xuất tôm sạch đạt chuẩn GMP và phát triển bền vững ở các tỉnh ven biển miền Tây Việt Nam.
3

Autonomous water-cleaning machine using solar energy in shrimp ponds: Research article

Dang, Thien Ngon 14 November 2012 (has links)
Limited water exchange shrimp culture technology is commonly used today in many shrimp farms in Vietnam to reduce water usage, input of diseases and discharge of nutrient-rich effluents into environment as well as to increase the production per unit area. However, a remaining problem in this technology is that the water quality in shrimp ponds will be reduced due to limitation of water exchange for a long period. The accumulation of inorganic components such as waste feed, bacterial deposits or other biological debris at the pond bottom will lead to low dissolved oxygen, high ammonia-nitrogen level, high fecal coliform bacteria and high turbidity which cause a severe degradation of water quality and detriment to shrimp growth and survival. To solve this remaining problem, an autonomous water-cleaning machine for shrimp ponds was designed to control the waste accumulation in the pond. This is an effective solution to replace manual cleaning methods for water quality management in shrimp farming in the coastal area of the Mekong delta of Vietnam. Especially, this technique can be used for biosecure shrimp production systems according to GMP standards to meet the objectives for sustainable development of shrimp aquaculture in Vietnam. / Kỹ thuật nuôi tôm không thay nước đang được sử dụng rộng rãi ở các trại nuôi tôm Việt Nam vì giúp giảm lượng nước sử dụng, hạn chế thải nước vào môi trường và giúp tăng diện tích nuôi trồng tôm. Tuy nhiên, bản thân kỹ thuật này cũng tạo nên một sản phẩm chất thải là phân tôm, thức ăn và chế phẩm sinh học xử lý nước dư thừa. Chất thải này dần dần tích tụ dưới đáy ao tạo thành lớp bùn độc, rất thiếu ôxy và chứa nhiều chất gây hại như ammonia, nitrite, hydrogen sulfide. Để tránh làm giảm diện tích ao nuôi do chất thải tích tụ làm tôm lảng tránh và tăng mật độ tôm nuôi trồng, thiết bị tự hành thu gom chất thải làm sạch nước trong vuông nuôi tôm đã được nghiên cứu, thiết kế và chế tạo thành công. Thiết bị đã thay thế các hoạt động làm sạch chất thải thủ công của con người, không sử dụng các nguồn năng lượng gây ô nhiễm, giảm nhu cầu về điện góp phần phát triển sản xuất tôm sạch đạt chuẩn GMP và phát triển bền vững ở các tỉnh ven biển miền Tây Việt Nam.
4

Which remote sensing indicators to survey shrimp farms in activity and to rehabilitate abandoned sites? / Quels outils de télédétection pour suivre les bassins aquacoles en activité et pour réhabiliter les sites abandonnés ?

Gusmawati, Niken Financia 13 July 2017 (has links)
La production de crevettes en Indonésie est en constante augmentation de part sa surface et l'intensification de ses élevages. Cette filière contribue au développement économique en milieu rural, à la sécurité alimentaire nationale, à l'emploi et au commerce extérieur. Cependant, ce développement rapide s'est accompagné d'effets écologiques et sociaux négatifs. Le développement de maladies dans les élevages ainsi que la dégradation de l'environnement côtier a conduit à l'abandon de 250 000 hectares de bassins dans le pays. Leur réhabilitation dans le cadre d'une activité durable est aujourd'hui une priorité pour le gouvernement indonésien.L'objectif de cette thèse est de développer des outils et des méthodes, basées sur de l’imagerie satellites à très haute résolution spatiale (THRS), (1) pour une meilleure gestion des sites de production et (2) pour réhabiliter les sites abandonnés. L'estuaire de la Perancak situé dans la Province de Bali, une zone de production en déclin, a été choisi comme site pilote. Ce travail a été réalisé dans le cadre du projet INDESO dont l'objectif était de fournir des outils et des méthodes pour une meilleure gestion des ressources côtières et marines en Indonésie.Le premier outil développé pour objectif de cartographier automatiquement les bassins d'élevage. A cet effet, une méthode basée sur la détection des contours a été mise en place et comparée à deux autres méthodes, la première basée sur la méthode de croissance des régions, la seconde sur une classification non supervisée (plus particulièrement la méthode Isocluster). Notre méthode a permis de détecter une forte proportion de bassins avec une meilleure précision.Le second outil avait pour objectif de distinguer les bassins actifs des bassins abandonnés. Un indicateur intégré (IPAI) basé sur quatre critères identifiés sur les images THRS que sont la présence d'eau, d'aérateur(s), de ponton(s) d'alimentation et de végétation, a été développé. Cet indicateur permet de distinguer significativement un bassin actif d'un bassin inactif. La présence de ponton est le critère qui s'est révélé être le plus discriminant.Cet indicateur a été utilisé sur l'estuaire de la Perancak pour suivre la dynamique d’abandon des bassins, liée au développement des maladies dans les élevages, entre 2001 et 2015. Deux facteurs de risque conduisant à l'abandon ont été mis en évidence : le climat et le positionnement des bassins au sein de l'estuaire. Ces résultats suggèrent qu'une approche spatiale doit être prise en compte pour la réhabilitation des bassins. Trois zones ont été définies à partir de leur résilience spatiale aux maladies. Le niveau de connectivité entre des bassins via le réseau hydrologique augmente le risque d'abandon. A noter que la présence actuelle des pathogènes (White Spot Syndrome Virus, WSSV) dans les bassins et probablement dans l'environnement génère une mémoire écologique défavorable à la réhabilitation de fermes aquacoles de crevettes.A partir de ces résultats, une première proposition de plan pour réhabiliter les bassins abandonnés a été formulée dans le cadre d'une approche écosystémique. Pour lutter contre les maladies, ce plan suggère de développer une aquaculture multi-trophique intégrée (AMTI), basée sur la diversité des espèces élevées et de leur positionnement dans la chaine trophique, à l'échelle de l'estuaire. Les méthodes et les études qui doivent être conduites pour rendre opérationnelle cette proposition sont discutées. / Shrimp farming production in Indonesia has continuously increased through a large expansion of cultured areas and stocking density intensification. This activity supports rural economic development and contributes to national food security, employment and foreign exchange earnings. However, this development has generated adverse ecological and social effects. As consequences of diseases and environmental degradations, there are currently 250,000 ha of abandoned ponds. Their rehabilitation, within a sustainable aquaculture framework, is actually a high priority for the Indonesian government.The objective of the present PhD work was to develop tools and methodologies to (1) enable better management for operating sites of shrimp industry and (2) rehabilitate abandoned sites using very high-resolution satellite (VHRS) imagery. The Perancak Estuary, located in Bali Province, is the production area in decline that has been chosen as study site. This work has been carried out in the frame of the INDESO project which was assigned to develop and provide tools and methods for better management of marine and coastal resources in Indonesia.The first developed tool was an automatic classification procedure for aquaculture mapping. A method based on Edge Detection on VHRS images was proposed and compared with those generated by Region Growing segmentation and unsupervised classification Isocluster. Edge Detection method could successfully create aquaculture map in the Perancak estuary by identifying a large proportion of existing ponds, with good overall accuracy.To implement effective procedure for appropriate aquaculture ecosystem assessment and monitoring, the second tool was an Integrated Pond Activity Indicator (IPAI). It aimed to discriminate active from abandoned ponds and was developed based on four criteria using VHRS images. Those criteria were: presence of water, aerator, feeding bridge and vegetation. This indicator succeeded in detecting active pond with a good accuracy, and feeding bridge appeared to be the most discriminant criteria.This second indicator has then been applied to the Perancak estuary to highlight the abandonment dynamic due to disease between 2001 and 2015. Two risk factors that could contribute to explain dynamics of abandonment were identified: climate conditions and pond locations within the estuary, suggesting that a spatial approach should be integrated in planning processes to operationalize pond rehabilitation. Three areas were defined based on their disease resilience. Ponds connectivity through water network increased the risk of disease development. The continued presence of shrimp pathogen species in ponds and probably in the environment (i.e. White Spot Syndrome Virus, WSSV) may generate ‘ecological memories’ that prevent to the return of shrimp productive system.These results were used to establish a first proposal of rehabilitation plan using an ecological approach. At the whole ecosystem scale, the development of an integrated multi-trophic aquaculture (IMTA), based on the diversity of cultured species and their trophic status would be implemented. Methods and studies that would be conducted to operationalize sustainable pond rehabilitation are briefly discussed.
5

Diagn?stico ecotoxicol?gico dos efluentes lan?ados no complexo estuarino do Jundia?/Potengi, Natal/RN

Nicodemo, Sinara Cybelle Tur?bio e Silva 21 May 2010 (has links)
Made available in DSpace on 2014-12-17T14:02:01Z (GMT). No. of bitstreams: 1 SinaraCTSN_DISSERT.pdf: 2908664 bytes, checksum: ab5d0fd4fae3407675ed29d3bfa6ed5f (MD5) Previous issue date: 2010-05-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Untreated effluents that reach surface water affect the aquatic life and humans. This study aimed to evaluate the wastewater s toxicity (municipal, industrial and shrimp pond effluents) released in the Estuarine Complex of Jundia?- Potengi, Natal/RN, through chronic quantitative e qualitative toxicity tests using the test organism Mysidopsis Juniae, CRUSTACEA, MYSIDACEA (Silva, 1979). For this, a new methodology for viewing chronic effects on organisms of M. juniae was used (only renewal), based on another existing methodology to another testorganism very similar to M. Juniae, the M. Bahia (daily renewal).Toxicity tests 7 days duration were used for detecting effects on the survival and fecundity in M. juniae. Lethal Concentration 50% (LC50%) was determined by the Trimmed Spearman-Karber; Inhibition Concentration 50% (IC50%) in fecundity was determined by Linear Interpolation. ANOVA (One Way) tests (p = 0.05) were used to determinate the No Observed Effect Concentration (NOEC) and Low Observed Effect Concentration (LOEC). Effluents flows were measured and the toxic load of the effluents was estimated. Multivariate analysis - Principal Component Analysis (PCA) and Correspondence Analysis (CA) - identified the physic-chemical parameters better explain the patterns of toxicity found in survival and fecundity of M. juniae. We verified the feasibility of applying the only renewal system in chronic tests with M. Juniae. Most efluentes proved toxic on the survival and fecundity of M. Juniae, except for some shrimp pond effluents. The most toxic effluent was ETE Lagoa Aerada (LC50, 6.24%; IC50, 4.82%), ETE Quintas (LC50, 5.85%), Giselda Trigueiro Hospital (LC50, 2.05%), CLAN (LC50, 2.14%) and COTEMINAS (LC50, IC50 and 38.51%, 6.94%). The greatest toxic load was originated from ETE inefficient high flow effluents, textile effluents and CLAN. The organic load was related to the toxic effects of wastewater and hospital effluents in survival of M. Juniae, as well as heavy metals, total residual chlorine and phenols. In industrial effluents was found relationship between toxicity and organic load, phenols, oils and greases and benzene. The effects on fertility were related, in turn, with chlorine and heavy metals. Toxicity tests using other organisms of different trophic levels, as well as analysis of sediment toxicity are recommended to confirm the patterns found with M. Juniae. However, the results indicate the necessity for implementation and improvement of sewage treatment systems affluent to the Potengi s estuary / Efluentes sem tratamento pr?vio adequado, ao atingirem corpos d ?gua, afetam a biota aqu?tica e o ser humano. Este trabalho objetivou avaliar a toxicidade dos efluentes (sanit?rios, industriais e de despesca) que atingem o Complexo Estuarino do Jundia?/Potengi, Natal/RN, atrav?s de testes cr?nicos qualitativos e quantitativos utilizando o organismo-teste Mysidopsis juniae, CRUSTACEA, MISIDACEA (Silva, 1979). Para isso, uma nova metodologia para visualiza??o de efeitos cr?nicos em organismos de M. juniae foi usada (renova??o ?nica), baseada em outra metodologia existente para outro organismo-teste bastante similar ao M. juniae, o M. Bahia (renova??o di?ria). Testes de Toxicidade cr?nicos com dura??o de 7 dias foram aplicados para detectar efeitos dos efluentes na sobreviv?ncia e na fecundidade dos organismos testados. Para a determina??o da Concentra??o Letal (CL50), utilizou-se o m?todo Trimmed Spearman-Karber; para a determina??o da Concentra??o de Inibi??o (CI50) da fecundidade, utilizouse o m?todo de Interpola??o Linear. M?todos de An?lise de Vari?ncia ?nico Fator (p=0,05) foram usados para a determina??o da Concentra??o de Efeito N?o Observ?vel (CENO) e da Concentra??o de Efeito Observ?vel (CEO). As vaz?es de descarga dos efluentes foram medidas e estimou-se a carga t?xica dos efluentes. Foram realizadas an?lises multivariadas de ordena??o - An?lise de Componentes Principais (ACP) e An?lise de Correspond?ncia (AC) - para identificar quais os par?metros f?sico-qu?micos dos efluentes que melhor explicam os padr?es de toxicidade encontrados na sobreviv?ncia e na fecundidade de M. juniae. Com esse trabalho verificou-se a viabilidade da aplica??o do sistema de renova??o ?nica nos testes cr?nicos com M. juniae. A maioria dos efluentes se mostrou t?xicos quanto ? sobreviv?ncia e fecundidade de M. juniae, com exce??o de alguns efluentes de despesca, sendo os mais t?xicos o efluente da ETE Lagoa Aerada (CL50, 6,24% e CI50, 4,82%), ETE Quintas (CL50, 5,85%), Hospital Giselda Trigueiro (CL50, 2,05%), CLAN (CL50, 2,14%) e COTEMINAS (CL50, 38,51% e CI50, 6,94%). Nos efluentes de carcinicultura foi verificada maior toxicidade em efluentes coletados ao final do per?odo de despesca, o que denota que ela foi causada pela excessiva carga org?nica. Os efluentes sanit?rios de maior carga t?xica foram os efluentes originados das ETEs ineficientes de alta vaz?o, enquanto que os industriais de maior carga t?xica foram, em geral, os efluentes t?xteis e o da CLAN. A carga org?nica relacionou-se com os efeitos t?xicos dos efluentes sanit?rios e hospitalar na sobreviv?ncia de M. juniae, assim como metais pesados, cloro residual total e fen?is. Nos efluentes industriais verificou-se rela??o entre toxicidade e carga org?nica, fen?is, ?leos e graxas e benzeno. Os efeitos sobre a fecundidade relacionaram-se, por sua vez, com cloretos e metais pesados. Testes de toxicidade utilizando outros organismos, bem como an?lises da toxicidade do sedimento, s?o recomendados para confirmar os padr?es encontrados com o M. juniae. Os resultados dos testes indicam a necessidade de implementa??o e melhoria dos sistemas de tratamento de efluentes que s?o conduzidos ao estu?rio do Rio Potengi

Page generated in 0.0458 seconds