蚊子湖及淖尔特湖卤虫资源量的研究

蚊子湖面积100hm^2，淖尔特湖面积60hm^2，两湖卤虫虫体年资源量分别为96、14．3t，卤虫卵资源量分别为1．5～3．5、0．5～1．75t。两湖水位变动大。卤虫及虫卵资源量出现较大波动。卵虫开捕期应定为8月中旬，开发卤虫卵资源相对容易且经济。     

蚊子湖及淖尔特湖卤虫某些生物学特性的研究

通过野外调查及室内实验 ,掌握了蚊子湖及淖尔特湖卤虫生物学特性。蚊子湖及淖尔特湖卤虫均属两性生殖种群 ,繁殖方式属卵生卵胎生混合型 ;食物由有机碎屑、嗜盐菌及藻类组成 ;干燥卵径分别为 2 1 4 2± 8 0um、 2 2 2 5± 1 0 9um ;壳厚分别为 7 4um、8 5um ;克卵量分别为 2 8 2 5万粒 /g、 2 7 2 3万粒 /g。     

青海卤虫资源面临灭绝

卤虫是当今国内外广泛利用的活饵料，尤其适合对虾养殖。位于柴达木盆地、面积为 34.7平方公里的青海尕海湖内蕴藏着丰富的卤虫资源，年资源量可达 15000吨以上，是中国内陆盐湖卤虫资源中的佼佼者。卤虫资源成为当地群众脱贫致富，带动地方经济发展的优势产业。由于高额利润的驱使和政府管理力量的薄弱，卤虫的捕捞、销售等环节长期处于混乱状态，滥捕滥捞的人员多达五六千人，捕捞量已超过可捕量，造成资源的严重破坏。去年全年生产干卵不足 10吨。照此下去，尕海湖的卤虫资源有灭绝的危险。 (本刊资料 )青海卤虫资源面临灭绝…     

尕海湖卤虫资源开发的制度选择与分析

卤虫(Artemia salina)是名优水产养殖品种的开口活饵料,因其自然孵化率高、品质优等特点深受沿海地区水产养殖户的青睐,市场需求量极大,供不应求,价格一直攀升。青海省是全国少数几个有天然卤虫分布的省份之一,尕海湖是青海省柴达木盆地生产卤虫的最大咸水湖泊,卤虫     

中国内陆盐湖卤虫资源开发利用的研究

我国内陆盐湖卤虫资源分布地区约有４３处，其中重点产区有内蒙古的额吉淖尔、黄旗海；青海的尕海、小柴旦湖；新疆的艾比湖、巴里坤湖；山西的解池等７处。卤虫资源量为２５０００～３００００ｔ／ａ；卤虫卵５００～７００ｔ／ａ；可开发量：鲜卤虫１５００ｔ／ａ，原料卤虫卵２００～３００ｔ／ａ。研究了主要盐湖卤虫生物学特性和投喂对虾幼体的饵料效果以及卤虫的孵化特性和加工工艺。并对我国内陆盐湖卤虫资源进行了评估，提出了繁殖保护和开发利用的意见。     

卤虫养殖条件初探

正本文通过测定不同品系——乌兹别克斯坦盐湖、哈萨克斯坦盐湖、俄罗斯盐湖以及渤海湾盐田卤虫卵的孵化率、孵化量,筛选出最优种卤虫——渤海湾盐田孤雌生殖卤虫品系后进行后续实验,研究了饵料对卤虫生长速率影响,环境因素对卤虫室外生产影响等,为室内高密度养殖及户外大规模养殖卤虫提供参考依据。     

富春湖银鱼基地建设浅析

本文概述富春湖气象条件、水文特征、饵料生物及银鱼资源状况，就建设银鱼出口基地及移植基地，进行初步探讨。     

中国西北地区盐湖卤虫资源的评估

作者在对我国西北地区盐湖卤虫资源普查的基础上,对内蒙的额吉淖尔“黄旗海,青海的尕海、小柴旦湖,新疆的艾比湖、巴里坤湖和山西的解池等7个盐湖卤虫产区进行了重点调查。根据我国盐湖分布特点,湖水面积大小,湖水深浅,卤水盐度及湖区气候特点等,对我国西北地区盐湖卤虫资源进行了评估,可供各级领导机关决策和生产单位开发利用时参考。     

湖荡水面开发围网养蟹

湖荡水面开发围网养蟹王帮琳（江苏省兴化市水利局２２５７００）江苏省兴化市地处长江、淮河下游，地势低洼，河湖密布，水面占全市总面积的２５７％，水面资源十分丰富，是发展水产养殖的理想基地。据测算湖荡水面被开发利用达７０％以上。在取得水产经济效益的同时，...     

冶湖开发使新招

冶湖位于临湘县和岳阳市北区的五个乡镇十三村之间，湖内水草茂盛，资源丰富，临湘县自1984年起就部署开发利用该湖，但由于种种原因，开发工作几起几落，到1988年底，湖内仍然是迷魂阵密布，电船来往穿梭，沿湖渔民大多是使用害业酷鱼滥捕，湖内资源濒临枯竭，生产秩序混乱不堪。面对这种情况，1989年初县委，县政府经过多次研究，决定采用分而治之的办法，     

Role of small-scale fishing in Kompong Thom Province, Cambodia

ABSTRACT:   Household surveys of small-scale fishing were conducted in Svay Ear and Srey Rangit villages in Kompong Thom Province, Cambodia. Data were collected from 104 of 183 households and 105 of 140 households in Svay Ear and Srey Rangit, respectively. In both villages, almost all households conducted rice cultivation and approximately 75% of them also conducted fishing. Three fishing groups: (i) inside lake; (ii) around lake; and (iii) around village were observed in both villages, according to their main fishing grounds. The inside lake group conduct fishing only in Tonle Sap Lake which is located 30 km away from the villages. The around lake group fish in lakes, marshes and flooded forests adjacent to Tonle Sap Lake, which are more than 5 km from the villages. The around village group collects fish from rice fields and ponds located inside the villages and also in some streams, rivers and lakes adjacent to the villages. The distance to the fishing grounds is less than 5 km from the villages. Most fishing groups were the inside and around lake groups, which occupied 76.0 and 65.7% of Svay Ear and Srey Rangit, respectively. These two groups produced 80.6 and 69.7% of the respective village annual total fish catches. These two groups sold a large portion of their fish catches. Although previous reports indicated that small-scale fishing is for subsistence, present results indicated that small-scale fishing was commercially conducted and fishing was important as an income source.     

青海湖裸鲤种群数量变动的初步分析

青海湖裸鲤是青海湖唯一的捕捞对象。开发后的种群数量变动主要根据1975-1977年该湖渔获物资料及过去研究的裸鲤生物学特性。计算了该种群的若干特征值，应用BevertonHolt数学模式计算不同捕捞努力量或用不同网目的拖网对裸鲤种群在一生中总个体数、总生物量，和对裸鲤种群一生中能捕捞的总个体数及总渔获重量的影响，以及裸鲤的最大持续产量和现有种群数量。评价了裸鲤资源利用现状，提出有关生产的一些初步意见。     

Efficiency of oxbow lake management systems in Bangladesh to introduce cage culture for resource-poor fisheries

A total of 5488 ha of oxbow lakes in Bangladesh has recently gained importance as a potential fishery resource. The growing need to utilize this resource to a fuller potential requires consideration of cage culture by resource-poor fishing communities as a compliment to existing stock enhancement programmes. In the present study, the existing management systems of eight lakes are reviewed. Water quality was analysed with reference to the largest lake, i.e. Lake Baluhar. During the present study, > 100 cm transparency indicated the suitability of a lake for cage culture. Other water quality parameters, especially dissolved oxygen, ammonia and nitrite concentrations, also indicated suitability for cage culture. Non-fisheries activities, such as the use of agricultural pesticides in the lake catchment and jute retting in its basin, were identified as the most harmful to fish by the majority of the fishermen. An integrated pest management programme using rice–fish based rearing systems in the lake catchment is recommended. It is further recommended that a unified management system should replace the existing dispersed systems under different management bodies.     

卤虫在WSSV病毒病传播中的媒介作用

2003年8月对卤虫进行投喂(浸泡)感染，并进行中国明对虾投喂实验。各组对虾阳性感染率的单因素方差分析比较结果表明，卤虫可以携带有活性的WSSV病毒粒子，并可通过摄食导致对虾间接地携带病毒，但病毒感染能力有限。卤虫病理切片观察结果显示，攻毒后卤虫细胞核没有显著深染及核肿大现象，但无论是横切还是纵切均显示有上皮脱落、部分组织结构松散、细胞结构不完整现象。本试验确定卤虫成体可以携带WSSV并通过投喂感染对虾，使其潜在携带病毒，仔虾阶段投喂成体卤虫应经过严格检疫，制作含有经过检疫卤虫的微囊饵料作为卤虫及其他鲜活饵料的替代品或许是有效的防病措施。     

太湖短吻银鱼秋季人工授精、孵化和早期发育的研究

太湖短吻银鱼Neosalanx tangkahkeii taihuensis Chert是太湖中的重要经济鱼类之一。为了探索这一银鱼秋季能否产卵和孵出仔鱼，作者曾于1975年秋季在太湖进行人工授精和孵化实验研究。结果共孵出仔鱼543尾；此外，还固定了各胚胎时期的发育卵465粒。通过孵化材料，联系到亲鱼在生殖时期需要得到保护，因而建议每年10月8日至24日限制或禁止使用银鱼渔具捕捞，使之能够正常产卵，以达到天然鱼类的增殖和合理利用银鱼资源的目的。     

Management and restoration of fish communities in Lake Taihu, China

The economic development of the cities around Lake Taihu, China, has caused both environmental changes and ecological succession. The biodiversity of Lake Taihu has declined since 1970. Migratory fish, including anadromous, catadromous and semi-migratory fish, are either extinct or on the verge of extinction in Lake Taihu. Only lake dwellers persist. Several measures have been taken, such as restocking, closed seasons, sanctuaries for enhancement and even introductions to restore some original fish communities. Although these measures have achieved a certain degree of success, increased fishing activities or over-fishing have offset the benefits obtained. Moreover, cultural eutrophication of the lake and the pollution of the waterways connected with the lake are getting worse. This jeopardizes the remaining economically valuable species in the lake. Measures are required not only to control eutrophication and pollution, and to reduce the intensity of fishing, but also to address the wider biodiversity issues.     

长荡湖水生植被动态及其渔业效应的研究

本文根据1983年—1984年调查研究结果分析整理而成。文中论述了长荡湖现有水生植被的种类组成,群落结构,生态分布,沉水植物的生物量及其利用。经过分析比较,发现近30年来,长荡湖水生植被经历了旺盛—衰竭—恢复—旺盛的演替过程,揭示了引起植被变化的各种因素。随着水生植被的动态变化,长荡湖的鱼类种群结构,渔获对象及捕捞工具都相应发生了变化。植被的盛衰同浮游植物和浮游动物、底栖生物的消长丰歉有着密切的关系.本文最后指出了长荡湖水植被的演替趋势和潜在危机,强调了合理利用和定向改造水生植被的重要性,并对今后如何发展我国湖泊渔业提出了建议。     

冷冻等处理对不同孵化进程的卤虫卵存活率的影响

研究了冷冻、双氧水和干燥处理对处于不同孵化进程中的卤虫卵的存活率(孵化率)的影响。冷冻对未经孵化处理的卵的孵化率影响很小,冷冻1~8周,基本保持不变。孵化进行了3h的卤虫卵,冷冻8周后,其孵化率降低了10个百分点。孵化进行了6h的卤虫卵,冷冻8周后,其孵化率降低了31个百分点。孵化进行了9h的卤虫卵,冷冻8周后,其孵化率降低了40个百分点。处于不同孵化阶段的卤虫卵经冷冻处理8周后,再经3%双氧水处理10min和40℃干燥处理6h,其孵化率表现为不同的特点。未经孵化处理卵的孵化率基本保持不变。孵化进行了3h的卤虫卵,其孵化率再次降低5个百分点。孵化进行了6h的卤虫卵,其孵化率再次降低了20个百分点。孵化进行了9h的卤虫卵,其孵化率再次降低了37个百分点。     

Estimating angling effort and participation in a multi-user, inland fishery in South Africa

Abstract  Angler counts, on-lake interviews and a household survey were used to estimate angler effort and participation in Lake Gariep, South Africa's largest inland water body. Annual fishing effort was estimated from instantaneous counts at 16392 angler day⁻¹ yr⁻¹. Recreational and subsistence anglers contributed 41 and 59% to the total annual fishing effort, respectively. Household surveys in lakeshore settlements estimated that ≥914 anglers fished the lake and minimum daily fishing effort in one of the fishing areas assessed was 77 anglers. As a result of recall bias, these estimates were almost twice as high as those determined by direct counts. A low cost method of assessing participation by applying a mark–recapture model to the proportion of anglers whom had been previously interviewed during eight bimonthly sampling events was tested. The model converged in three of four applications (2 areas × 2 sectors). The mark–recapture method revealed similar numbers of anglers to the estimate of regular anglers (fishing 1–3 times a week) from the household survey and was considered an appropriate estimator for the number of subsistence anglers. Regardless of the assessment method the results show that the resource is of importance to subsistence livelihoods, which is an important management consideration in future fisheries development and rights allocation processes.     

Influences of gear type and analytical methodology on fish assemblage characterisations in temperate lakes

A variety of gears and analytical methods can be used to characterise lentic fish assemblages; however, the combined influence of gear type and analysis can affect conclusions about assemblage patterns. Fish assemblages sampled with night electric fishing, gillnets and trapnets from 153 lakes were evaluated using summary indices of species composition, pairwise community similarity comparisons and multivariate ordination. For a given amount of effort, electric fishing had the highest species richness, while gillnets had higher diversity and evenness. Pairwise comparisons between gears revealed that (1) richness was positively correlated among all gears, (2) diversity and evenness were generally not correlated across gears and (3) electric fishing and trapnets captured more similar species than all other pairwise comparisons. Gear‐specific multivariate correlation and ordination revealed that gillnet and electric fishing samples more similarly characterised variation in assemblages among lakes, while trapnets characterised assemblages along different gradients of species composition. These results indicate that either electric fishing or trapnetting can be used when assessing shallow‐water assemblages for diversity or evenness, gillnets and either electric fishing or trapnets should be used for whole‐lake assessments, and either gillnets or electric fishing should be used when evaluating regionwide variation in lake assemblages.