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Suitability evaluation on marine ranching in Guangdong,South China 被引量:1
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作者 Anning SUO Weiguo ZHOU Dewen DING 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第2期778-791,共14页
The ecological suitability of marine resources and environmental conditions for marine ranching in Guangdong,South China was evaluated.Niche theory was used to establish an ecological suitability evaluation model for ... The ecological suitability of marine resources and environmental conditions for marine ranching in Guangdong,South China was evaluated.Niche theory was used to establish an ecological suitability evaluation model for marine ranching site selection,and suitability evaluation of marine ranching was conducted in.Results show that the ecological suitability index of marine ranching site selection was greater than 64.0 in 20 sites,including offshore Shantou Bay,offshore Zhanjiang Port,and Longdou Bay etc.,which are the priority areas for marine ranching.In other 13 sites,the ecological suitability index ranged between 8.0 and 32.0,including Houjiang Bay,Haimen Bay,and Jieshi Bay etc.,indicating the suitability for marine ranching.However,the ecological suitability index was 0 in Shantou Bay,Zhujiang(Pearl)River estuary,Huangmao Sea,Guanghai Bay,Zhanjiang Port,Qiongzhou Strait,and Anpu Port.These sites are thus unsuitable for marine ranching.This study provides a theoretical basis for site selection and planning of marine ranching in Guangdong Province. 展开更多
关键词 marine ranching site suitability EVALUATION ecological niche Guangdong Province
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Marine Ranching Engineering Collaborative Innovation from the Perspective of Ecological Environment
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作者 WAN Xiaole ZHANG Guixian LI Qianqian 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期1151-1163,共13页
As a resource development model with both economic and ecological functions,the environmental friendliness of marine ranching products meets the environmental needs of consumers.However,the lack of technological innov... As a resource development model with both economic and ecological functions,the environmental friendliness of marine ranching products meets the environmental needs of consumers.However,the lack of technological innovation ability limits the development of marine ranching.Therefore,this research builds a marine ranching collaborative innovation system with multi-agent participation.Evolutionary game theory is used to analyze strategic choices of all parties and the conditions of system equilibrium,and numerical simulation is used to analyze the effect of relevant factors.This paper integrates the benefits from the improvement of environmental friendliness into the payoff matrix,and explains the significance of collaborative innovation to the development of marine ranching from the perspective of ecological environment.The results showed:the participation willingness of marine ranching enterprises is positively related to open innovation subject,while the participation willingness of the other two parties is negatively related to the government;The incentive effect of collaboration is negatively correlated with the government’s will,positively correlated with the other two parties;The incentive effect of government subsidies positively affects the willingness of the three parties to participate.Finally,suggestions are provided for each participant to maintain the strategic choice of marine ranching collaborative innovation system. 展开更多
关键词 marine ranching engineering ecological environment collaborative innovation evolutionary game numerical simulations
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Remote Sensing Assessment of Ecological Effects of Marine Ranching in the Eastern Guangdong Waters, China 被引量:1
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作者 Yanfeng Wang Jing Yu Pimao Chen 《Journal of Geoscience and Environment Protection》 2018年第12期101-113,共13页
This study aims to assess ecological effects of the construction of marine ranching in the eastern Guangdong waters. Variations in sea surface temperature (SST), chlorophyll a concentration (Chl-a), catch per unit eff... This study aims to assess ecological effects of the construction of marine ranching in the eastern Guangdong waters. Variations in sea surface temperature (SST), chlorophyll a concentration (Chl-a), catch per unit effort (CPUE), biodiversity, biomass and density of benthos were compared during the pre- (August in 2011) and post- (August in 2013) marine ranching. These were based on satellite remote sensing and survey data. Results showed that the ratio of Nitrogen (N): Phosphorus (P) was closed to 16, Chl-a increased from 7.5 - 12.3 mg·m-3 to 10.4 - 16.2 mg·m-3, and CPUE increased from 2.1 - 5.5 kg·h-1 to 5.8 - 14.5 kg·h-1. The species number of fish, crustaceans, cephalopods and shellfish increased by 25, 3, 2 and 3 respectively. Shannon-Wiener biodiversity index of fish, crustaceans, cephalopods and shellfish increased by 0.5, 0.4, 0.1 and 1.0 respectively. Both biomass and density of benthos increased also. The construction of marine ranching in the eastern Guangdong had restored the habitat to some extent, and played positive effects in the conservation and proliferation of fishery resources in local area. 展开更多
关键词 Marine ranching ECOLOGICAL Effects Remote Sensing EASTERN GUANGDONG WATERS China
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Progress on Research and Construction of Marine Ranching along the Coast of Shandong Province of China 被引量:1
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作者 Jiao Li Changtao Guan +4 位作者 Yong Cui Jufa Chen Jun Wang Wei Yuan Baoqing Yang 《Journal of Shipping and Ocean Engineering》 2014年第11期338-347,共10页
As a new fishery mode of low-carbon economy, marine ranching has played an important role in promoting sustainable development of fishery and construction of ocean economic zone in China. Since the year of 2000, envir... As a new fishery mode of low-carbon economy, marine ranching has played an important role in promoting sustainable development of fishery and construction of ocean economic zone in China. Since the year of 2000, environment improvement, stock enhancement and mariculture development have been given very high degree of importance along the coast of Shandong Province of China. Studies and tests on artificial reefs and marine ranching, including effect investigation of artificial reefs set up in Jiaonan coastal areas in 1980s, hydrodynamic characteristics experiment of artificial reef, study on material and configuration of artificial reef models, algae transplantation and seaweed beds construction, stock enhancement and releasing etc., have been carried out in recent years. Furthermore, the Restoration Plan of Fishery Resources of Shandong Province has been implemented since the year of 2005, which greatly boosted the construction of artificial reefs and marine ranching along the coast of Shandong. By June of 2010, the total investment on the construction of artificial reefs and marine ranching is over $77 million USD. One hundred artificial reef districts, with total area about 33,350,000 m2 have been set up. The construction of marine ranching along the coast of Shandong Province has been in certain scale and the economic, social and ecological effects are obvious. 展开更多
关键词 Marine ranching artificial reef seaweed beds stock enhancement Shandong Province.
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Maximum sustainable yield estimation of enhancement species with the characteristics of movement inside and outside marine ranching
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作者 Yingbin WANG Wei ZHANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第6期2380-2387,共8页
Marine ranching can be regarded as a type of artificial fishery,and its construction aims at the sustainable utilisation of fishery resources.Therefore,the sustainable yield level of target species in marine ranching ... Marine ranching can be regarded as a type of artificial fishery,and its construction aims at the sustainable utilisation of fishery resources.Therefore,the sustainable yield level of target species in marine ranching has become one of the concerns of stakeholders.The enhancement surplus production model proposed by Wang(2021)based on the traditional surplus production model can be used to assess the sustainable utilisation of settled species in marine ranches.However,when the target species has the characteristics of migration inside and outside marine ranches,its sustainability assessment will be aff ected.Based on the movement range and resource density levels of enhancement species inside and outside marine ranches,we built a biomass change model that is suitable for enhancement species with migration characteristics inside and outside marine ranches(migration enhancement biomass model).Moreover,we simulated the effects of factors,such as the ratio of the movement range and the ratio of resource density within and outside marine ranches and the fishing strategy for the enhancement species in marine ranches,on the estimation of maximum sustainable yield(MSY).Results show that the large movement range of enhancement species outside marine ranches was associated with the obvious advantage of the proposed migration enhancement model over the traditional enhancement production model.A small difference in the densities of enhancement species inside and outside marine ranches was highly beneficial for improving the accuracy of MSY estimation.The migration enhancement biomass model proposed in this study provides an idea for estimating the MSY of an enhancement species that migrates inside and outside marine ranches.Researchers can adjust the parameters of the model in accordance with the actual situation of resource distribution and changes to improve the scientificity of fishery stock assessment. 展开更多
关键词 marine ranching stock enhancement and releasing MIGRATION production model maximum sustainable yield(MSY)
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Current Situation, Problems and Countermeasures of Marine Ranching Development in Guangdong Province, China
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作者 Huarong YUAN Pimao CHEN 《Asian Agricultural Research》 2022年第11期1-10,14,共11页
Combining the literature review and marine field investigation in the sea area,this article summarized the development and current situation of marine ranching at home and abroad.It analyzed the construction process o... Combining the literature review and marine field investigation in the sea area,this article summarized the development and current situation of marine ranching at home and abroad.It analyzed the construction process of artificial fish reefs,proliferation and release,and national-level marine ranching demonstration areas,as well as the current development situation and existing problems of marine ranching-related industries in Guangdong Province.Guangdong has built 50 ecological artificial reef areas,3 large-scale artificial reef demonstration areas,1 local artificial reef area and 15 national marine ranching areas,with a total sea area of 1499.68 km^(2),and 2.004 million m^(3) of reefs.However,there are some problems in Guangdong marine ranching,including imperfect management mechanism,inconsistence in development concept and understanding,unclear rights and responsibilities in using sea area,lack of construction technology standards and specifications,low scientific and technological level and limited industrial development.In view of these problems,this article came up with countermeasures,including insisting on ecology-prioritized development,and strengthening the coordination of multiple departments;creating a management mode conducive to market-oriented operation;breaking through the issue of sea area ownership;establishing a technical standard system for marine ranch construction in Guangdong;strengthening the research on the basis of high-quality construction and key common technologies of Guangdong marine ranching;establishing industrialization modes of Guangdong marine ranching according to local conditions.Understanding the development status of marine ranching in Guangdong and exploring the development strategies of marine ranching industry by referring to the relevant experience at home and abroad can provide references for the effective management,efficient and sustainable development of marine ranching in Guangdong and the integration of three industries in the development of marine ranching in Guangdong. 展开更多
关键词 Marine ranching Artificial reef Enhancement and release Industrial integration Ecological priority
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Promoting integrated development of marine ranching and offshore renewable energy in China
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作者 SHAO Shuai 《Ecological Economy》 2019年第3期228-232,共5页
The integrated development of marine ranching and offshore renewable energy is a new development mode of marine industry which develops and uses marine resources intensively and ecologically.China has taken the lead i... The integrated development of marine ranching and offshore renewable energy is a new development mode of marine industry which develops and uses marine resources intensively and ecologically.China has taken the lead in carrying out active exploration,which is of great significance for implementing the concept of green development,seizing the opportunity of Marine economic development and promoting the construction of modern marine ranching.However,in the initial stage of integrated development,in order to ensure sustainable development,it is necessary to focus on the major problems that have emerged or may arise in the areas of ecological protection,technology research and development,financial support and policy support.To solve or prevent these problems,we should strengthen policy toplevel design,policy innovation,international cooperation and first-mover advantage. 展开更多
关键词 MARINE ranching OFFSHORE RENEWABLE rnergy INTEGRATED development
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Feasibility analysis and implementation of marine ranching integration of offshore wind power development in Guangdong Province
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作者 CHEN Hao LU Chuqian CHEN Bin 《Marine Science Bulletin》 2021年第2期57-72,共16页
Marine ranching is a new model for restoring marine ecological environment and conserving offshore fishery resources.Offshore wind power is a new clean energy industry in China.Based on the analysis of the constructio... Marine ranching is a new model for restoring marine ecological environment and conserving offshore fishery resources.Offshore wind power is a new clean energy industry in China.Based on the analysis of the construction of offshore wind farms in Guangdong Province,this article proposes to actively promote the integrated development of offshore wind power and marine ranching.The suitability and deployment conditions of Sargasso algae reef construction in offshore wind farms,the feasibility of developing an integrated development model featuring artificial algae reefs+offshore wind farms in Guangdong Province,as well as the importance of ecological sea area use and management were discussed.Regarding the necessity of intensive and economical utilization of sea and sea resources,it is believed that the development model of"marine ranching+offshore wind power"will become an important direction for improving the comprehensive utilization of sea areas in the future. 展开更多
关键词 marine ranching offshore wind power ecological restoration artificial algae reef
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Ecosystem service value of artificial reef area in Qingdao Luhaifeng sea ranching:A meta-analysis and benefit transfer valuation
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作者 LIU Ya-jun Paula NOVO 《Ecological Economy》 2022年第4期261-273,共13页
This study evaluates the ecosystem service value of Qingdao Luhaifeng Sea Ranch artificial reef area through the established meta-analysis value transfer model,and the results show that the total value will be 150 mil... This study evaluates the ecosystem service value of Qingdao Luhaifeng Sea Ranch artificial reef area through the established meta-analysis value transfer model,and the results show that the total value will be 150 million yuan in 2022.According to the regression results of the meta-analysis,the types of ecosystem services,the types of pasture sediment,the population density of the pasture area,and the economic level all have a significant impact on the wetland value.The model in this paper passes the validity test,and the conclusions are the same as many current empirical studies.This shows that the benefit transfer method meta-analysis can save assessment labor,time and capital,and the decision-makers can make judgments quickly.Meta-analysis is an effective and fast ex ante evaluation tool.The reliability of the value transfer method of meta-analysis largely depends on the quantity and quality of existing studies and the establishment of mathematical models.It is necessary to expand the number of literature searches.However,the current evaluation method of ecosystem services in China has just started,so the government needs to encourage research institutions to evaluate the value of ecosystem services to provide more effective and abundant research literature. 展开更多
关键词 sea ranching artificial reef ecosystem services benefit transfer META-ANALYSIS
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Game Ranching: A Sustainable Land Use Option and Economic Incentive for Biodiversity Conservation in Zambia
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作者 Chansa Chomba Chimbola Obias Vincent Nyirenda 《Open Journal of Ecology》 2014年第9期571-581,共11页
The ten provinces of Zambia were surveyed to determine number and size of game ranches situated in these areas up to the end of 2012/early 2013. Three classes of game ranches were developed as;1) ≥500 hectares as gam... The ten provinces of Zambia were surveyed to determine number and size of game ranches situated in these areas up to the end of 2012/early 2013. Three classes of game ranches were developed as;1) ≥500 hectares as game ranch proper, 2) ≥50 - <500 hectares as game farm, and 3) <50 hectares as ornamental. A total of 200 game ranches keeping large mammals from the size of common duiker to eland were recorded with a growth rate of 6 per year for the period 1980-2012. The largest number was ornamental 98 (49%);large game ranches were 75 (38%) and the least was game farms 27 (14%). Thirty seven species of large mammals were recorded, of which, 15 were the most abundant with impala topping the list with 21,000 individuals (34%). It was found that of the ten provinces, Luapula, Western and Northern Provinces despite being largely rural with low population densities except for Luapula did not have any game ranch. The province with the largest number was Lusaka 71(36%), Southern 59 (30%), Central 31(16%), Copperbelt 19 (10%), Eastern and Northwestern 9 (4.5% each) and Muchinga was the least with 2 (1%). The rapid increase in the number of ornamental category is mainly attributed to the rise in the development of tourist accommodation facilities and high cost residential properties. This growth provides an opportunity to convert to game ranching schemes abandoned farmlands which are not currently useful to agriculture due to loss of fertility and other forms of land degradation. Similarly, parcels of land with natural ecological limitations should also be considered for such schemes. Rehabilitation of degraded land through ranching could also enhance carbon sequestration, a factor critical in minimizing carbon emissions and other green house gases. 展开更多
关键词 GAME RANCH PROVINCE Number Species INCREASE Carbon Emissions
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The suitability assessment on site selection for bottom seeding scallop culture based on analytic hierarchy process
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作者 Ziniu ZHANG Zhenyan WANG +2 位作者 Guihua LI Meihan ZHAO Wenjian LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期647-663,共17页
Scallop culture is an important way of bottom-seeding marine ranching,which is of great significance to improve the current situation of fishery resources.However,there are some problems in site-selection evaluation o... Scallop culture is an important way of bottom-seeding marine ranching,which is of great significance to improve the current situation of fishery resources.However,there are some problems in site-selection evaluation of marine ranching,such as imperfect criteria system,complex structure,untargeted criteria quantification,etc.In addition,no site-selection evaluation method of bottom-seeding culture areas for scallops is available.Therefore,we established a hierarchy structure model according to the analytic hierarchy process(AHP)theory,in which social,physical,chemical,and biological environments are used as main criteria,and marine functional zonation,water depth,current,water temperature,salinity,substrate type,water quality,sediment quality,red tide,phytoplankton,and zooplankton are used as sub-criteria,on which a multi-parameter evaluation system is set up.Meanwhile,the dualism method,assignment method,and membership function method were used to quantify sub-criteria,and a quantitative evaluation for the entire criteria was added,including the evaluation and analysis of two types of unsuitable environmental situations.By overall consideration in scallop yield,quality,and marine ranching construction objectives,the weight of the main criteria could be determined.Five grades in the suitability corresponding to the evaluation result were divided,and the Python language was used to create an evaluation system for efficient calculation and intuitive presentation of the evaluation outcome.Eight marine cases were simulated based on existing survey data,and the results prove that the method is feasible for evaluating and analyzing the site selection of bottom-seeding culture areas for scallops under various environmental situations.The proposed evaluation method can be promoted for the site selection of bottom-seeding marine ranching.This study provided theoretical and methodological references for the site selection evaluation of other types of marine ranching. 展开更多
关键词 marine ranching bottom-seeding scallops site selection evaluation analytic hierarchy process evaluation system
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Influences of Family Ranches Management Mode on Plant Community Characteristic in Hulunber Meadow Steppe 被引量:1
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作者 闫瑞瑞 卫智军 +5 位作者 杨桂霞 韩国栋 辛晓平 卢志红 斯琴毕力格 吴宏军 《Agricultural Science & Technology》 CAS 2013年第11期1664-1669,共6页
[Objective] The aim was to explore the management mode on optimal re-sources al ocation of family ranch in meadow steppe. [Method] Three double repre-sentative family ranches were selected in meadow steppe of Hulunber... [Objective] The aim was to explore the management mode on optimal re-sources al ocation of family ranch in meadow steppe. [Method] Three double repre-sentative family ranches were selected in meadow steppe of Hulunber Old Barag Banner, and the study was carried out with the baseline survey. Three family ranches were selected as the demonstrative households for the corporation study, while other three family ranches with the similar conditions were looked as the non-demonstrative households for the comparison. Demonstrative households of the fami-ly ranches reduced the stocking rate, optimized the flock structure and took a winter feeding and other means to explore the different management models on plant com-munity characteristic of family ranch. [Result] The seasonal dynamic of community characteristic in family ranches showed the single-peaks curves. The seasonal dy-namics of community coverage, height and biomass in the demonstrative households showed higher compared with the non-demonstrative households, and community density in the experiment households was lower than that of the control experiment households. Community coverage, height and biomass of degraded grassland in family ranch have a great improve after optimization of management. Community coverage, height , density and biomass were increasing in fencing plot, but decreas-ing in free grazing area. Enclosure improved grassland coverage, vegetation height, density and forage yield. Leymus chinensis played an important role in plant com-munity. The important values of Leymus chinensis, Stipa baicalensis, Cleistogenes squarrosa, and Carex duriuscula were high. Leymus chinensis important value in the demonstrative households of optimal management was higher than that in the non-demonstrative households, and Carex duriuscula important value of the non-demon-strative households was significantly higher than that of the demonstrative house-holds. The indexes of Margalef richnes,Shannon-Wiener diversity, Simpson diversity and Pielou uniformity showed that the demonstrative households were higher than the non-demonstrative households. [Conclusion] The research provides theoretical ref-erences for sustainable development of pastures dominated by family ranch. 展开更多
关键词 Family ranches Management mode Hulunber meadow steppe Community characteristic
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Research Advances in Hydrodynamics of Artificial Reef 被引量:1
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作者 Fan Jiangtao Chen Pimao +1 位作者 Feng Xue Chen Guobao 《Animal Husbandry and Feed Science》 CAS 2014年第3期154-158,共5页
With further recession and deterioration of offshore fishery resources and increasing living demands, construction of marine ranching becomes a focal point to improve marine biological resources and environment, while... With further recession and deterioration of offshore fishery resources and increasing living demands, construction of marine ranching becomes a focal point to improve marine biological resources and environment, while artificial reef is one of the important parts for marine ranching construction. The artificial reef technology develops slowly in China compared with developed countries, such as the United States and Japan, and there are still many issues urgently to be solved. When an artificial reef is released in water, there are various kinds of forces, and its forces and flow field-effect are closely related to surrounding conditions and its own performance. Currently, there are no mature conclusions on research of hydrodynamics of artificial reef. According to review of hydrodynamics of artificial reefs, we hope to give a full understanding on hydrodynamics performance of artificial reefs, and provide reference and theoretical basis for further research on design and structure of artificial reef in China. 展开更多
关键词 Marine ranching Artificial reef HYDRODYNAMICS STABILITY
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Acoustic Conditioning System Development and Conditioning Experiments on Black Seabreams in the Xiangshan Bay Sea Ranch
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作者 HU Qingsong RAHMAN Hafiz Abd ur +2 位作者 JIANG Yazhou ZHANG Shouyu SHENTU Jikang 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第3期667-674,共8页
Attracting released hatchery-reared fish to designated areas during the growth process is vital to realize the objectives of sea ranching. Based on the bottom artificial reefs and surface kelp culture facilities in th... Attracting released hatchery-reared fish to designated areas during the growth process is vital to realize the objectives of sea ranching. Based on the bottom artificial reefs and surface kelp culture facilities in the Xiangshan Bay sea ranch, we proposed systematic techniques related to acoustic conditioning of the black seabream(Sparus macrocephalus). Experiments conducted in 12 m × 10 m × 1.6 m ponds on Xixuan Island showed that black seabream was positively sensitive to 500–600 Hz periodic signals. Conditioned responses were apparent after 8 d. Two to three days were required for recovery of the memory of a conditioned response after a 20-day interval. According to the practical application requirements in the open sea, unattended acoustic conditioning equipment was developed. The ranching equipment was used in 12 m × 12 m × 2.5 m cages, and the behavior of black seabream juveniles was successfully guided after 7 days. Of the 16000 released fish, 82.5% of them were conditioned with a flexible grading net. To avoid inducing a stress response, the juveniles were released into the sea ranch in situ from the net cage. The acoustic conditioning equipments were moved into the open sea and the aggregation phenomenon of the released fish was observed when the sound was played. After 6 months of investigation and based on Sr+ marking, only one acoustically conditioned fish was found outside the 3.5-km^2 sea ranch area, thereby reached the goal of guiding activity. The practical effect in the Xiangshan Bay sea ranch showed the validity of the acoustic conditioning system, which may contribute to improve the operation of the sea ranches in the East China Sea. 展开更多
关键词 sea ranch black seabream ranching equipment acoustic conditioning aggregation
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Long-Term Fate of Agent Orange and Dioxin TCDD Contaminated Soils and Sediments in Vietnam Hotspots 被引量:5
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作者 Kenneth Ray Olson Lois Wright Morton 《Open Journal of Soil Science》 2019年第1期1-34,共34页
The soils, tropical climate, and network of canals and rivers of southern Vietnam have created one of the most diverse tropical jungles and intensely cultivated landscapes of Southeast Asia. This paradise has a long h... The soils, tropical climate, and network of canals and rivers of southern Vietnam have created one of the most diverse tropical jungles and intensely cultivated landscapes of Southeast Asia. This paradise has a long history of numerous wars, foreign occupations, and most recently the Second Indochina War (aka the Vietnam War 1965-1972) which defoliated rain forests and ancient wetland mangroves and left behind contaminated soil and sediment hotspots. During this war, the United States (US) military sprayed 80 million liters of Agent Orange contaminated with the dioxin TCDD in a guerrilla war against communist insurgents. Agent Orange was a synthetic plant growth regulator comprised of equal amounts of two herbicides 2,4-dichloro phenoxyacetic acid C8H6Cl2O3 (2,4-D) and 2,4,5-trichlorophenoxyacetic acid C8H5Cl3O3 (2,4,5-T). TCDD, the dioxin, 2,3,7,8-tetrachlorodibenzodioxin (C12H4Cl4O2) was an unintended byproduct of the accelerated combustion process used in the manufacture of herbicides containing 2,4,5-T. Agent Orange has frequently been blamed for soil and sediment contamination and long-term human health problems;however, the true source of harm is the dioxin TCDD. Agent Orange has a short half-life of days and weeks after application to vegetation, and has not been found to persist, after 50 years, in the water or soils of southern Vietnam. However, the half-life of dioxin TCDD depends on where it is deposited and varies from 1 to 3 years on soil surfaces that have been fully exposed to sunlight, to as long as 20 to 50 years or more when buried in tropical subsoils, and more than 100 years in river and sea sediments. Dioxin TCDD was heavily concentrated in the US Air Force bases in Vietnam where the herbicides were stored, loaded on planes and helicopters for aerial spraying, and used extensively around military base perimeter fences as a security measure to prevent surprise attacks. Bien Hoa Air Force base, 40 km northeast of Ho Chi Minh City, continues to be one of the mega-hotspots where after 48 years the dioxin TCDD levels in fish and shrimp are still high and fishing is banned in ponds and lakes adjacent to the airbase. Although expensive, one of the most effective remediation to dioxin TCDD contaminated soils is incineration which is the recommended method of dioxin TCDD disposal. 展开更多
关键词 Soils of VIETNAM Agent Orange DIOXIN TCDD Herbicides SOIL CONTAMINANT Sediment CONTAMINANT Half-Life HOTSPOTS Operation Ranch Hand US Airbases in VIETNAM VIETNAM War Cu Chi SOIL Tunnels Guerilla Warfare Incineration
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A Reassessment of Birth Defects for Children of Participants of the Air Force Health Study 被引量:1
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作者 George J. Knafl 《Open Journal of Epidemiology》 2018年第4期187-200,共14页
The Air Force Health Study (AFHS), also called the Ranch Hand Study, investigated the impact of exposure to dioxin the toxic contaminant in Agent Orange on health, survival, and reproductive outcomes of male Air Force... The Air Force Health Study (AFHS), also called the Ranch Hand Study, investigated the impact of exposure to dioxin the toxic contaminant in Agent Orange on health, survival, and reproductive outcomes of male Air Force Vietnam War veterans. It was concluded that available reproductive outcome data did not provide support for an adverse association with paternal dioxin exposure. A more extensive set of AFHS data was used to reassess this conclusion, restricting to the case of birth defects in children fathered after the start of the first Vietnam War tour. Analyses started by repeating published analyses, followed by assessing decisions made in those analyses, for example, of excluding participants with dioxin levels below the detectable limit, using a threshold of 10 parts per trillion for a high dioxin level, and not adjusting for multiple conceptions/children of the same participant. Using data for all participants with measured dioxin levels, both veterans who served in Operation Ranch Hand and other non-Ranch Hand veterans, and after accounting for correlation within children of the same participant, the occurrence for children fathered after the start of the first tour of a major defect, a non-major defect, and multiple defects depended significantly on participants having a high dioxin level. These conclusions were not changed by consideration of covariates. In contrast to prior published analyses, the more extensive AFHS data provided support for an adverse effect of paternal dioxin exposure on birth defects. However, the study had many limitations that could have affected the conclusions. 展开更多
关键词 BIRTH Defects Cross-Validation DIOXIN Operation RANCH HAND
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Agent Blue Spraying in the Mekong Delta during the Vietnam War: Fate of the Arsenic Based Herbicide Weapon Used to Destroy Rice Crop and Mangrove Forests 被引量:1
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作者 Kenneth R. Olson Larry Cihacek 《Open Journal of Soil Science》 CAS 2022年第7期253-294,共42页
Agent Blue, a mixture of cacodylic acid (CH<sub>3</sub>) As O<sub>2</sub>H) and sodium cacodylate (C<sub>2</sub>H<sub>6</sub> AsNaO<sub>2</sub>), was a tacti... Agent Blue, a mixture of cacodylic acid (CH<sub>3</sub>) As O<sub>2</sub>H) and sodium cacodylate (C<sub>2</sub>H<sub>6</sub> AsNaO<sub>2</sub>), was a tactical arsenic-based herbicide used during the Vietnam War to destroy grasses and rice crops. Natural and synthetic sources of arsenic can degrade into water-soluble forms and persist in groundwater and potentially contribute to elevating As levels in drinking water. The United States Department of Defense (DOD) and United States Department of Agricultural (USDA) Operation Ranch Hand records for tactical herbicides including Agent Blue sprayed in southern Vietnam during the Vietnam War (1961-1971) are very detailed, rather complete and publicly available. The same is not true for tactical herbicides sprayed by the Republic of Vietnam (RV) during the Khai Quang program which was supported by the U.S. Army, U.S. Navy and Central Intelligence Agency (CIA) in the Mekong Delta. Agent Blue was sprayed by the RV military for three years before the official start of the American-Vietnam War. Few, if any, RV military, US Army, US Navy and CIA spray records exist from 1962 to 1965. Vietnam War veterans, historians and scholars have reported the spraying of 3.2 million liters (468,008 kg As) of Agent Blue on rice paddies and mangrove forests in the Mekong Delta and Central Highlands by the RV military with the support of the US Army, US Navy and CIA. The Institute of Medicine estimated that 3.2 million liters (468,000 kg As) were sprayed during the RV Khai Quang program. This was in addition to the U.S. Air Force’s Operation Ranch Hand spraying of the tactical herbicide Agent Blue primarily by C-123 aircraft. The Operation Ranch Hand missions maintained location and quantities of herbicides sprayed (over 4,712,000 liters (664,392 kg As) from 1961-1971. The RV military and US military (Army and Navy) spray equipment included hand and backpack sprayers, sprayers mounted on Brown Water Navy boats, on Army track vehicles and Army land-based helicopters and helicopters based on the decks of Blue Water Navy ships. Some of these spray missions were a military secret and spray records were classified or if kept were not maintained. Agent Blue containing cacodylic acid had a short half-life and degraded to water-soluble arsenic, which was released into the surface water and/or leached into the groundwater. Once the water-soluble arsenic leached into the Vietnam Mekong Delta groundwater, the arsenic-rich water was pumped back to the surface by tens of thousands of tube wells for urban and agricultural use. The primary objectives of this research are to explore the conditions during the Vietnam War under which 1) the RV military herbicide spray program with the support of the US Navy, CIA and US Army, and 2) the US Air Force spray program during Operation Ranch Hand may have significantly contributed to the natural and anthropic As spikes found in the Mekong Delta today. The environmental impacts of Agent Blue, on the Menominee River at manufacturing sites in the United States, were studied to identify possible As remediation and mitigation strategies. The lessons previously learned at the manufacturing sites in Wisconsin and Michigan, United States can be considered and applied to the Mekong Delta to help mitigate and remediate the arsenic-rich surface water, soil, sediment and groundwater found in the Mekong Delta. 展开更多
关键词 Operation Ranch Hand Khai Quang program Agent Blue ARSENIC Cacodylic Acid North Vietnam Army Republic of Vietnam Democratic Republic of Vietnam American-Vietnam War
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选择造就了我们——杰夫·贝索斯在普林斯顿大学2010届毕业典礼上的演讲 被引量:1
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作者 Jeff Bezos 胡君 《新东方英语(中英文版)》 2013年第12期38-41,共4页
你会不会因自己天资聪颖而沾沾自喜?会不会因自己头脑灵光而以捉弄别人为乐?你该如何利用自己的天资?如何作出正确的抉择?下面就让我们来听一听亚马逊的创始人杰夫贝索斯在普林斯顿大学毕业典礼上所作的演讲。通过演讲,他希望告诉大家:... 你会不会因自己天资聪颖而沾沾自喜?会不会因自己头脑灵光而以捉弄别人为乐?你该如何利用自己的天资?如何作出正确的抉择?下面就让我们来听一听亚马逊的创始人杰夫贝索斯在普林斯顿大学毕业典礼上所作的演讲。通过演讲,他希望告诉大家:聪明是一种天资,善良是一种选择,最终造就我们的并非天资,而是一路走来的各种选择。As a kid,I spent my summers with my grandparents on their ranch1)in Texas.I helped fix windmills2),vaccinate3)cattle,and do other chores.My grandparents belonged to a Caravan4)Club,a group of Airstream5)trailer6)owners who 展开更多
关键词 普林斯顿大学 毕业典礼 杰夫 cattle RANCH belonged SPENT really think CAREFUL
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Design of Ranch Fire Monitoring System Based on Zig Bee Technology
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作者 Chao ZHANG 《Asian Agricultural Research》 2015年第3期96-98,共3页
This paper designs a way to introduce Zig Bee technology into the ranch fire monitoring system,and builds a real-time ranch fire monitoring system based on Zig Bee wireless sensor network.The system can monitor the pa... This paper designs a way to introduce Zig Bee technology into the ranch fire monitoring system,and builds a real-time ranch fire monitoring system based on Zig Bee wireless sensor network.The system can monitor the parameters related to ranch in real time,such as air moisture,temperature and smoke density,so as to provide information support for ranch fire prevention and extinguishment.This paper researches the circuit design of Zig Bee wireless sensor network node,node information collection,data fusion,transmission and effective topological structure of sensor network. 展开更多
关键词 ZIGBEE FIRE MONITORING RANCH
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Physicochemical Characteristics, Degradation Rate and Vulnerability Potential of Obudu Cattle Ranch Soils in Southeast Nigeria
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作者 A. U. Akpan-Idiok K. I. Ofem 《Open Journal of Soil Science》 2014年第2期57-63,共7页
Obudu Cattle Ranch covers an area of 2400 hactares at an altitude of 900 - 1500 m above mean sea level and is suitable for cultivation of cucumber (Cucumis sativus), tomato (Solanum lycopersicum), Irish potato (Solanu... Obudu Cattle Ranch covers an area of 2400 hactares at an altitude of 900 - 1500 m above mean sea level and is suitable for cultivation of cucumber (Cucumis sativus), tomato (Solanum lycopersicum), Irish potato (Solanum tuberosum), spinach (Spinacia oleracea) cabbage (Brassica oleracea), lettuce (Lactuca sativa) because of its semitemperate climate. Physicochemical characteristics, degradation rates and vulnerability potential of the soils were studied. Eighteen composite soil samples (0 - 15 and 15 - 30 cm) were collected at interval of 500 m along North-South and East-West transects in nine locations. The soils were characterized as follows: texture of sandy loam for the surface and subsurface soils;pH(H2O) (4.7 - 5.7), organic carbon (4.9 - 74.8 gkg-1), total nitrogen (0.2 - 4.8 gkg-1), carbon-nitrogen ratio (14 - 25), available P (6.66 - 107.89 mgkg-1), effective cation exchange capacity (ECEC) (5.58 - 14.62 cmol·kg-1) and base saturation (49.37% - 85.28%);the surface soils were generally higher in organic carbon, total nitrogen, available P and ECEC than the subsurface. The Soil Degradation Rate (SDR)/ Vulnerability Potential (Vp) weighted values of texture (3/3), soil pH(H2O) (4/2), organic carbon (1/5) and base saturation (2/4) showed moderate to low susceptibility of the soils to degradation or vulnerability. The soils could be managed by liming, practicing crop rotation and using soil conservative measures. 展开更多
关键词 PHYSICOCHEMICAL Characteristics Obudu CATTLE RANCH Soil Degradation VULNERABILITY POTENTIAL
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