对虾配合颗粒饲料水中稳定性的测试方法

阐述了对虾配合颗粒饲料中稳定性的概念，介绍并讨论了各种评价及测试方法的优缺点，包括感官法、光度法、COD法、干燥称重法。作者指出，应采用多项参数对对虾配合颗粒料水中稳定性进行综合评价。     

对虾配合饲料预混料中试项目通过专家论证

上海延安制药厂研制的对虾配合饲料预混料研究成果,于1990年1月23日通过专家鉴定。对虾配合饲料预混料采用了微粉化工艺,含量均匀、吸收良好,质量稳定可靠,经过101天的对虾试养,均有明显的效果。为确保研究成果稳定性,上海延安制药厂对虾配合饲料预混     

中国对虾配合饲料入水后营养成分的流失及其对水环境的影响↑（*）

对中国对虾配合饲料浸于水中营养成分的流失及其对水环境的影响作了分析，发现目前生产使用的配合饲料水中稳定性较差。实验结果表明：１．配合饲料入水后便会失去部分重量，５分钟好达１２．４￣１３．２％，１２０分钟可达１７．０￣２３．９％。配合饲料在浸泡过程中，各营养成分的溶失速度不一，水易溶性物质溶失迅速且彻底，造成溶失比例不一致，破坏了配合饲料原有的营养平衡体系，降低了其营养价值。３．配合饲料投入水中会引     

对虾饵料水中稳定性及其测定方法

对虾饵料的水中稳定性,是衡量对虾饵料质量的一个重要指标,它直接关系到对虾的喂养效果,在一定程度上关系到饵料的饲料系数,甚至关系到对虾的正常生存。对虾饵料的水中稳定性差,会增加饵料的需要量,影响养殖对虾的效益以及养殖水质的污染,使养殖水域富营养化,造成水质污染。几年来,     

对虾配合饲料粘合剂的筛选与应用

随着对虾人工养殖业的发展，人工配合饲料的应用日益普遍。为使饲料的有效营养成份不易流失，虾池水质不被污染，饲料在水中须有一定耐水性。目前，提高饲料耐水性的方法有二：一是饲料生产工艺流程的改进；二是在饲料中添加粘合剂。国外通常使用的对虾饲料粘合剂有：羧甲基纤维素、褐藻酸钠、琼胶、动物胶、变性淀粉、活性谷蛋白、树脂类等。国内的对虾饲科粘合剂大多为小型饲料生产工艺之用，饲料成型后含水份高，需经晒干或烘干才能包装。本试验旨在筛选出适合大规模生产对虾配合饲料工艺流程的粘合剂，结果如下。     

提高水产饲料水中稳定性的措施

水产饲料水中稳定性是指饲料在水中浸泡一定时间后,保持组成成份不被溶解和不散失的性能。一般以一定时间内饲料在水中的散失量与饲料质量之比的百分数(即散失率)表示,也可用饲料在水中不溃散的最少时间表示。技术上鱼饲料水中散失率小于20%(浸泡30min),对虾饲料水中散失率小于12%(浸泡2h),同时,要求饲料在浸泡的过程中表面形成一种保护膜,使料中的水溶性元素不被溶失。否则,容易造成饲料的浪费、水体的污染、消化吸收的障碍和饵料系数的提高。因此,饲料的水中稳定性是评价渔用饲料的一项重要指标。本文笔者就如何提高水产饲料水中稳定性予…     

AAC—Ⅰ型配合颗粒饵料粘合剂研制成功

近年来我国对虾养殖生产迅速发展,鲜活饵料供应日趋紧缺,故各地都在开展对虾人工配合饲料的研制和试养。但当前实际使用的颗粒饵料都普遍存在着粘合性差,易在水中溶解,使对虾难以寻食,直接影响对虾生长。此外,颗粒饵料在水中溶散,既导致饵料浪费,又易造成水质污染,为解决上述养虾生产上存在的突出问题,浙江省海洋水产研究所温州分所经过十九批次,八十多个不同项目的对比试验,现已成功地研制出一种AAC—I型高效粘     

生产对虾饲料应注意的要点

近年来，随着国家对水产养殖业的重视，以及受国外水产养殖技术的影响，我国的水产养殖业发展迅猛。尤其是斑节对虾（草虾）、日本对虾（花虾）、墨吉对虾（白虾）的养殖，越来越引起养殖业主的重视。养殖业主对对虾料的要求也越来越高。由于对虾的消化系统短而且细，消化吸收能力差，所以对虾饲料的加工要求远比普通畜禽饲料的加工要求高。下面，着重探讨一下生产对虾饲料应注意的几个要点。 １．水中稳定性（耐水性） 对虾饲料要求在水中的稳定时间要长，一般要求达到２ｈ以上。如果生产出来的颗粒饲料耐水性差，则不适应虾类的采食特点，…     

提高对虾配合饲料质量的探讨

提高对虾配合饲料的质量，对于提高对虾养殖产量和规格及提高养虾经济效益，关系十分密切。现就对虾配合饲料生产上的几个问题谈一些看法。     

提高水产饲料水中稳定性的措施

水产饲料在水中的稳定性是指饲料在水中浸泡一定时间后,保持组成成份不被溶解和不散失的性能.一般以一定时间内饲料在水中的散失量与饲料质量之比的百分数(即散失率)表示,也可用饲料在水中不溃散的最少时间表示.技术上鱼饲料水中散失率小于20%(浸泡30min),对虾饲料水中散失率小于12%(浸泡2h),同时,要求饲料在浸泡的过程中表面形成一种保护膜,使料中的水溶性元素不被溶失.否则,容易造成饲料的浪费,水体的污染,消化吸收的障碍和饵料系数的提高.因此,饲料的水中稳定性是评价渔用饲料的一项重要指标.本文笔者就如何提高水产饲料水中稳定性予以介绍,仅供业内人士参考.     

Economical ways of assessing hydrography for fish farms

When selecting or developing a marine site for aquaculture, it is frequently useful to be able to assess salinity, current speeds, oxygen levels, water temperatures and exposure. These factors are considered in relation to Scottish west coast sea lochs. A method is given to estimate salinity from a map-based study of catchment areas and loch areas as well as by field observations using inexpensive equipment. Similarly, methods of taking sub-surface water samples, determining oxygen content and measuring current speeds are described. A graph is presented to predict wave heights from wind speed and fetch. The methods described have been chosen to give adequate information with minimum expenditure on equipment.     

水产品活运原理与方法

综述了国内外水产品保活运输的研究进展和影响水产品保活运输存活率的五大因素(水产品种类与体质、氧气供给量和消耗量、温度、水质环境和水产品的应激性)，介绍了运用麻醉、生态冰温、常规降温和模拟冬眠等方法进行水产品保活运输的原理，同时对水产品保活运输方法的发展趋势也进行了预测。     

Oxidative Stability of Dried Seafood Products during Processing and Storage: A Review

Drying is a traditional and important seafood processing technology. Lipid oxidation is one concern during the processing and storage of dried seafood products. Various factors including pretreatment, drying method, and storage conditions can have an impact on the oxidative stability of dried seafood products. Influence of these factors on the oxidative stability of dried seafood products as well as the possible mechanisms are reviewed. This review could serve as a reference for the production and research of dried seafood products.     

Ecological drivers of fish metacommunities: Environmental and spatial factors surpass predation in structuring metacommunities of intermittent rivers

Metacommunity theory is a new approach for explaining how local and regional processes contribute to community organisation and integrative studies are needed to fully characterise the processes underlying its structure and function. We analysed, through variation partitioning and distance decay relationships, how metacommunities of fish in pools of intermittent rivers are structured by environmental, species interaction and spatial factors. The results indicate that both species sorting and dispersal limitation (spatial factors) were important in shaping fish metacommunities. Species sorting was the most influential driver within fish metacommunities, but predation was much less relevant and did not show any pure effect in metacommunity structure. However, environmental factors were determinant among metacommunity patches.     

乔木种植位置对岸坡深层锚固作用的影响——以永定河泛区为例

以永定河泛区中天堂河下游段两岸作为研究区域,探究该区域不同类型乔木种植位置对岸坡整体锚固作用的影响,确定坡地区域与坡顶区域最佳的乔木种植方案,以解决洪泛区湿陷性粉质粘土岸坡坡脚处易失稳的安全隐患。采用拓扑根系描绘法、最大摩擦锚固力计算法、经验公式模型法以及ABAQUS有限元模拟法,分别对根系的形态、根系的固土性能、根系力学特性以及锚固岸坡整体稳定性进行分析。研究结果表明（：1）由于紫荆根系具有较为发达的须根,因而具有较强的锚固性能,相较于紫荆,榆叶梅锚固性能相对较差,在同一深度的埋置条件下,二者的锚固性能相差幅度为5%～25%(;2)当坡地区域的紫荆位于坡脚处,且坡顶区域的榆叶梅位于距离坡肩1.8 m处的种植位置时,岸坡的安全系数达到2.153,岸坡的抗滑锚固效果可达到最佳。坡顶区域与坡地区域的乔木种植位置可对粉质粘土坡体稳定产生双重耦合的影响,当坡地区域植株的种植位置处于坡脚处时,坡顶处任何区域的乔木根际土体均可与之形成有效的土拱效应,以遏制岸坡失稳。     

Comparative assessment of scoring methods to evaluate the conservation value of pond and small lake biodiversity

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