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1.
以安徽省巢湖市为实验区,以国产高分一号(GF-1)和资源三号(ZY-3)高分辨率遥感影像为数据源,以NDWI和纹理特征作为分类特征,联合随机森林、支持向量机和BP神经网络3种分类方法,发展了一种集成分类模型,用于提取养殖水体信息,并进行阴影剔除和形态学处理。结果表明,该集成分类模型适用于提取养殖水体信息,总体精度为97.4%,Kappa系数为0.87,漏分误差为3.7%,错分误差为6.4%,相比单个模型精度明显提高;针对GF-1影像的增强阴影水体指数,对山体阴影和城市建筑阴影的剔除效果明显,较大程度上避免了阴影对水体提取的干扰;实验区养殖水体的遥感动态监测应用发现, 2016年相比2013年水产养殖面积增加6.9%。该研究理论与技术成果的应用,有助于及时掌握养殖水体的时空分布及动态变化,快速提升中国渔业管理的信息化和科学化水平。  相似文献   

2.
水产养殖水质参数检测作为现代化水产养殖的重要特征正受到越来越多的关注。为满足水产养殖业对水质环境参数检测的迫切需求,研究设计了一种升降式水产养殖水质自动检测系统。该系统由无线传感模块和传感器保护模块构成,无线传感模块采用GPRS无线传感技术实现水质参数的采集和传送;传感器保护模块利用PIC16F877A型单片机作为控制器,通过ZigBee实现与服务器的远程通信,从而控制检测装置的升降和水质传感器的冲洗与保湿。通过PC或手机客户端,养殖户可以对检测系统进行实时监测和控制。结果显示,系统运行稳定,装配简易,操作方便,实现了对鱼塘水温、溶氧和p H的自动检测;远程控制反应时间在1 s以内,数据传输错误率基本为0;溶氧、p H和温度传感器的最大相对误差分别为0.55%、1.89%和1.32%。研究表明,升降式机械结构工作稳定,实现了传感器的冲洗、保湿功能,远程控制动作反应速度和测量精度达到水产养殖水质信息采集的要求,能够满足水产养殖水质检测的应用要求。  相似文献   

3.
4.
为提供实际生产理论依据,改良系统水处理工艺,开展循环水养殖系统中吉富罗非鱼氮收支和对水质情况的初步研究。起始养殖密度8 kg/m3,投饲率2%,系统循环量1 m3/h,总水量0.8 m3。试验期间溶解氧大于6 mg/L,pH 7.0~7.2,水温23~25℃。每周监测水质2~3次,监测指标包括氨氮、亚硝酸盐氮、硝酸盐氮,每2周检测1次水中总氮。用凯氏定氮法测定实验前后饲料、试验鱼体、粪便、悬浮颗粒的氮含量。结果显示,摄食氮有50.00±1.50%转化为生长氮,32.61±1.38%转化为排泄氮,17.39±4.0%转化为粪氮;58%的粪氮为悬浮颗粒物,42%为可沉淀颗粒物。  相似文献   

5.
2005—2010年,对天津市天祥水产有限公司封闭循环水养殖系统水质进行了检测。结果显示:养殖池塘是否覆膜、覆膜面积大小,均会使整个养殖系统中的总硬度(TH)、总碱度(AT)、NH3-N和PO4-P在时空上产生差异。时间上,它们年份间差异极显著(P<0.01);空间上,各采样点的AT和NH3-N差异显著(P<0.05)。覆膜使系统的TH和AT稳定性减弱,CV上升了166.5%~241.7%,这种情况在养殖中期尤为突出,但对NH3-N和PO4-P稳定性的影响并不明显。养殖系统中较大面积的覆膜(43.65%)对养殖池塘TH、AT和NH3-N稳定性的影响比非覆膜池塘的大,CV分别高出了75.9%、135.6%和21.6%;而小面积(19.2%)覆膜的养殖池塘相对非覆膜池塘稳定,CV分别降低了71.9%、41.5%和91.4%。导致它们间差异及稳定性变异的原因主要归结于覆膜影响了物质与土壤间的物质交换及其间的生物活性强度。  相似文献   

6.
Coastal water bodies are a particularly heterogeneous resource, typified by high spatial and temporal variability that could influence the aquaculture in coastal zones. However, the development of coastal aquaculture may produce negative impacts on the coastal area by the potential release of nutrients and organic matter that can be a source of pollution in receiving waters. The aim of this paper was to evaluate the performance of constructed wetland in controlling the dynamics of deoxygenating matter (organic matter and ammonia) and eutrophicating matter [organic matter and soluble reactive phosphorus (SRP)] in the waters entering (inflow) and flowing out (outflow) from a coastal aquaculture fish farm. We observed that constructed wetland systems are effective in removing fractions of total suspended solids, COD, total ammonia nitrogen and SRP contained in the inflow water with higher efficiency in the spring period (60.37%, 14.89%, 65.38% and 17.6% respectively) than in the summer period (45.10%, 8.06%, 32.43% and 8.00% respectively). Similar pattern was recorded for the treatment of the outflow waters, showing that the wetland system reduced most of the deoxygenating and eutrophicating matter produced as a consequence of feeding and fish metabolic activity. During the summer season, high algae mortality can reduce the performance of the wetland system in the outflow water control; this lower efficiency could be improved by controlling the biomass of algae by vegetation harvesting.  相似文献   

7.
应用多参数水质传感器、PAC场控制器、IEEE802.15.4无线传感器网络、CAN现场通信网络等技术进行系统设计,创建低成本、高效率、性能匀称、可扩充系统的水产养殖水质测试和水质调控的集成系统。认为推广普及规范化的水质监控手段,对促进水产养殖的科技进步和产业升级,实现水产养殖业增长方式转变有积极的意义。指出在现阶段发展我国的“数字化”养殖水质监控系统时,要注意现场设备的数字化、智能化、多功能化、网络化,开发低价位性能可靠的数字化水质传感器,提高信息的共享性和发挥养殖水质数据的应用价值。  相似文献   

8.
为探讨不同养殖模式对暗纹东方鲀生长及水质的影响,选取无损伤、健康的暗纹东方鲀7000尾,随机分成3种养殖模式:立体种养模式(模式Ⅰ)、单养模式(模式Ⅱ)和混养模式(模式Ⅲ),进行了为期56 d的养殖试验,比较3种养殖模式下暗纹东方鲀的生长速度、成活率以及养殖水质指标的变化。试验结果:模式Ⅰ暗纹东方鲀的成活率(97.10%)高于模式Ⅱ(92.35%)和模式Ⅲ(89.37%),特定生长率[(1.83±0.12)%/d]显著高于模式Ⅲ(P<0.05),饲料系数(2.20)则低于其他2种模式;模式Ⅱ下养殖水体的三态氮(TAN、NO2^--N和NO3^--N)无明显变化,其质量浓度略低于模式Ⅰ和模式Ⅲ,模式Ⅲ下三态氮的质量浓度有所升高,而模式Ⅰ下TAN和NO2^--N质量浓度有降低的趋势;3种养殖模式下,池塘水体的化学需氧量(COD)呈现先升后降再升的变化趋势,总悬浮物(TSS)呈现先升高后降低的趋势,其中模式Ⅰ的COD和TSS质量浓度均低于模式Ⅱ和模式Ⅲ;模式Ⅱ和模式Ⅲ下总氮(TN)质量浓度先降后升,而模式Ⅰ的TN质量浓度则是先降后升再降,且在14 d后均显著低于其他2种模式(P<0.05);模式Ⅱ和模式Ⅲ下总磷(TP)质量浓度无明显变化,模式Ⅰ下TP质量浓度在养殖初期有所升高,呈现先升后降的变化趋势,并在56 d时降至最低,显著低于模式Ⅱ和模式Ⅲ(P<0.05)。结果表明,在立体种养模式下,暗纹东方鲀不仅生长快,成活率高,而且栽种蕹菜对池塘养殖水体具有较好的净化作用,能减少池塘养殖水体富营养化,立体种养模式较单养和混养模式更适合暗纹东方鲀养殖。  相似文献   

9.
针对现有水产设备机械化和自动化程度较低,增氧机作用范围有限和投饲机无法自适应投饲的问题,研究设计了一种新型的基于实时水质参数的智能养殖装备。该装备硬件上利用传感器对水质参数进行实时监测,采用太阳能与交流电源混合供电。其中,移动式太阳能增氧机使用超声波测距进行避障,可随机行走、增大增氧机的工作范围;太阳能智能投饲机使用称重传感器进行饲料称重,以实现精确定量投饲。该装备软件上支持个人计算机和手机等多个平台客户端,实现实时水质参数查询、远程增氧、远程投饲、远程智能控制等功能。池塘应用试验结果表明,该装备的监测水质数据可信度高,实时通讯丢包率低于0.2%,在保证增氧能力的情况下,增氧机作用范围比传统水车式增氧机提高10%;能够在良好的水质环境中完成精确定量投饲。研究表明,该装备的应用有助于推进水产设备智能化、自动化的发展,实现节能降耗、绿色环保的目标。  相似文献   

10.
海洋遥感技术在海洋渔业及相关领域的应用与研究   总被引:3,自引:0,他引:3  
自20世纪70年代始,科研人员将遥感技术应用于海洋渔业及其相关领域的研究,将各类卫星遥感所获得的数据对海洋水温、海流、光、盐度、溶解氧、气象因素、水深、海底地形、饵料生物等进行了由定性到定量的分析,并将所得结果用于指导渔业生产、促进渔业研究、预警海洋灾害等方面,所起作用非传统调查方法能为。因此,遥感技术在海洋渔业及其相关领域正在发挥着越来越大的作用,并预示着广阔的应用前景和巨大的应用潜力。本文综述了遥感技术在海洋生态系统相关要素和渔场变动、大型动植物分布、海况监测、海洋生态污染及灾害监测等方面应用与研究进展,并对海洋遥感信息在我国海洋渔业领域的应用研究前景进行了分析。  相似文献   

11.
Abstract Global warming is expected to result in considerable changes in northern European freshwater fish populations, fisheries and aquaculture. Shifts towards cyprinid and percid dominance in fish assemblages are expected, together with a decrease and collapse of salmonid and other coldwater fish populations. Most of the evident changes will occur in shallow lakes, where no thermal stratification occurs. The potential ranges of some fish species will shift northwards but pronounced changes will occur in the relative abundance of individual fish species. Total fish production will increase but because of changed composition of fish communities the commercial and recreational value of catches will decrease. Salmonid aquaculture productivity will increase provided that fish farmers adapt to new circumstances and cold, oxygenated water is available in larger quantities during summer.  相似文献   

12.
The effects of system partition on the water quality were studied using three shrimp ponds (Ts), and each one of the shrimp pond was connected individually with a fish pond by piping and pump. Three other isolated shrimp ponds were designated as the Cs treatment. The results showed that the implementation of the system can improve the water quality in the shrimp ponds. Particulate organic matter (POM), chemical oxygen demand (COD), nitrite nitrogen (NO2–N) and nitrate nitrogen (NO3–N) in the Ts were lower than those in the Cs during the experiment, and in some cases, they were significantly lower (p < 0.05). Throughout most of the experimental period, the soluble reactive phosphorus in the Ts treatment were greater than that in the Cs treatment (p < 0.05), and N/P ratio of the water column was lower in the Ts treatment than in the Cs treatment throughout most of the experimental period (p < 0.05). These results indicate that the partitioned system contributed to the stability of water quality and N/P ratio in the water. Vibrio parahaemolyticus was dominant in the third to seventh weeks in Cs, and the dominant condition was found only in seventh week in Ts. The result indicated that system may contribute to the slowing down of the breakout of V. parahaemolyticus in the shrimp pond. According to the redundancy analysis, COD, chlorophyll a and POM were mainly positively related to the dominance index of V. parahaemolyticus, and maybe POM can serve as an indicator to reflect the trend of V. parahaemolyticus.  相似文献   

13.
在封闭循环水养殖条件下,半滑舌鳎(Cynoglossus semilaevis Günther)的平均养殖密度(15.07±0.22)kg/m3,观测半滑舌鳎的呼吸频率,检测养殖水体中溶氧、氨氮、亚硝酸氮等24 h内摄食和代谢的变化规律。结果表明:(1)半滑舌鳎摄食前、后的呼吸频率平均值分别为27.3次/min和34.7次/min,摄食后的呼吸频率显著高于摄食前;(2)投喂前、后2.5 h内,水中溶氧一直处于下降趋势,在摄食2.5 h后,水中溶氧处于稳定的上升趋势;(3)投喂后,氨氮、亚硝酸氮浓度显著增高,2.5 h后达到峰值,随后缓慢降低,在下次投喂前0.5 h达到最低值。说明半滑舌鳎摄食活动对循环水养殖水质的影响呈现规律性,也说明循环水养殖模式可以满足半滑舌鳎对水质的基本要求。  相似文献   

14.
Most research on gender difference or inequities in capture fisheries and aquaculture in Africa and the Asia‐Pacific focuses on the gender division of labour. Emerging research on globalization, market changes, poverty and trends in gendered employment within this sector reveals the need to move beyond this narrow perspective. If gleaning and post‐harvesting activities were enumerated, the fisheries and aquaculture sector might well turn out to be female sphere. A livelihoods approach better enables an understanding of how employment in this sector is embedded in other social, cultural, economic, political and ecological structures and processes that shape gender inequities and how these might be reduced. We focus on four thematic areas – markets and migration, capabilities and well‐being, networks and identities, governance and rights – as analytical entry points. These also provide a framework to identify research gaps and generate a comparative understanding of the impact of development processes and socioecological changes, including issues of climate change, adaptation and resilience, on gendered employment. Without an adequate analysis of gender, fisheries management and development policies may have negative effects on people’s livelihoods, well‐being and the environment they depend on, or fail altogether to achieve intended outcomes.  相似文献   

15.
王骥  谢再秘  莫春梅 《水产学报》2023,47(8):089502-089502
目前神经网络研究文献成果较多,虽然在水质精准预测方面起到了一定的参考,但由于文献缺少科学分类,使用率不高,导致学者难以找到研究切入点。针对这一问题,本文将神经网络方法在养殖区水质精准预测方面的文献按照海水和淡水两大领域进行分类,主要对每个领域所应用的预测模型从正反馈架构、循环架构和混合架构三个方向对海水时空序列文献进行分类研究和综述,发现混合架构模型的预测性能优于正反馈模型和循环架构模型,有利于提升不同深度水质预测模型的精度。另外,本文对基于神经网络方法的三维水质预测模型进行了初步探讨,发现学者的研究成果更多地集中在水表层和水中层的不同位置水质参数的变化方面,而神经网络方法对水表层水质预测精度比水中层和水深层水质预测精度高。  相似文献   

16.
大鹏澳网箱养殖海域水质评价及因子分析   总被引:3,自引:0,他引:3  
根据2001年6月至2002年6月对大鹏澳网箱养殖海域6个航次的水质监测数据,采用有机污染评价指数法对养殖区水质状况进行了评价,同时应用因子分析方法对T(水温)、DO、SS(悬浮物)、CoDMn、BOD5、NO2-N、NO3-N、NH3-N、TIN(总无机氮)、PO4-P等10个水质成分的监测数据进行了分析。结果表明,(1)2001年9月和2002年3月海水出现轻度污染,前者主要是由NO3-N、CoDMn和BoD5所引起,后者是由NH3-N、PO4-P引起的。(2)水质监测数据的总体方差主要来源于T、Do、SS、NO3-N及TIN等5个成分,其次是NO2-N、NH3-N、PO4-P,再次是CODMn和BOD5。(3)因子分析结果表明,各水质成分之间存在一定的相关关系。其中,T、Do、SS、NO3-N及TIN同时载荷于第1主因子上,说明此5个水质成分之间具有较好的相关性;NO2-N、NH3-N、PO4-P同时载荷于第2主因子上,则此3个水质成分之间的相关程性较好;CODMn和BOD5同时载荷于第3主因子上,二者之间具有较好的相关性。  相似文献   

17.
Aquaculture is one of the fastest growing food producing sectors in the world. The increase in the world population requires faster growth in aquaculture for better food availability and to overcome malnutrition. But this worldwide growth of aquaculture is overwhelmed by catastrophic fish diseases and spoilage during cultivation and preservation problems caused by pathogenic bacteria. Various remedies are available for food preservation and also from the bacterial diseases in the fish production. Due to the emergence of antibiotic resistance and adverse effects, an alternative to antibiotic is the need of the hour. The proteins such as bacteriocins, i.e. ribosomally synthesized antimicrobial peptides (AMPs) and possess antagonistic against closely related and other bacteria. These proteins are produced by most lineages of bacteria which are playing key roles in recognition and possess a cognate immunity system for self‐protection as well as host protection from infections. These proteins are potent immunomodulators with broad spectrum inhibition properties which are further used as novel therapeutic agents. In this review, we have tried to summarize the bacteriocins on the basis of their classifications, structural and functional attributes, mode of actions, bacteriocins isolated from fish and gut microbiota and presence of beneficiary bacteria in the fish gut. Further, this study highlighted where further research is a prerequisite to increase our basic understanding and search for novel bacteriocins to elucidate the proteins/peptides having antimicrobial properties for disease control in aquaculture as an alternative to antibiotics.  相似文献   

18.
复合生物过滤技术在水产养殖废水处理中的应用研究进展   总被引:1,自引:1,他引:1  
介绍了复合生物过滤技术的概念、原理、特点,以及植物滤器与微生物滤器复合生物过滤技术、动物滤器与植物滤器或微生物滤器过滤等主要几种复合生物过滤技术在实际生产中的应用,探讨了复合生物过滤技术在养殖废水处理中的发展趋势。  相似文献   

19.
Freshwater fish populations in England and Wales form an important resource with up to 2.2 million anglers involved in the recreational fishery. The resource consists principally of indigenous and naturalised cyprinids, and strongholds of species endangered elsewhere in Europe. Each component is under pressure from a range of sources including water abstraction and climate change. Water resources are under significant pressure and droughts in parts of England and Wales exposed the fragility of water supply systems. Climate change is a major concern, driving a re-assessment of water supply yields. There are no objective methods available to predict changes in fish communities likely to arise from different water resource management options, except for simple systems. It is difficult to manage water resources using anything other than a precautionary approach. Accurate assessment of environmental requirements are required to strike the right balance between the needs of aquatic ecosystems and of economic efficiency.  相似文献   

20.
Historically, the fishing community (e.g., fishermen, resource managers) has used remotely sensed products either in the form of direct Automatic Picture Transmission (APT) reception on a ship or FAX charts transmitted from land-based stations. Both these products have severe limitations within the context of near real-time support/management of an operational fishery. Moreover, relatively little use of geographical information systems (GIS) technologies has been made by either the fishing industry, fishery resource managers, or by the general oceanographic community. This latter omission is unfortunate because GIS has the potential to overcome two long-standing problems associated with satellite-directed fisheries: 1) the absence of information due to clouds; and 2) the general lack of support for nonpelagic fisheries. This report gives the background, motivation, and essential design elements for use of a combined remote sensing/geographical information system (RS/GIS) in an operational fishery and illustrates how a combined RS/GIS approach can be used to mitigate some of the traditional limitations in satellite-directed fisheries. Finally, an attempt is made to provide some possible directions this new technology may take during the 1990s.  相似文献   

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