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91.
为探讨黄连素对主要海水养殖病原菌的抑菌作用,采用二倍稀释法测定黄连素对迟缓爱德华氏菌、哈维氏弧菌等10种病原菌的最小抑菌质量浓度和最小杀菌质量浓度,并以美人鱼发光杆菌美人鱼亚种为指示菌,研究黄连素在不同温度、存储条件和金属离子影响下的药效稳定性。试验结果显示,黄连素对10种海水养殖病原菌均具有较好的抑菌及杀菌作用,最小抑菌质量浓度为64~256mg/L,最小杀菌质量浓度为256~1024mg/L。其中,黄连素对大菱鲆弧菌和溶藻弧菌抑菌作用最明显,最小抑菌质量浓度为64mg/L;对鳗弧菌、大菱鲆弧菌、迟缓爱德华氏菌、溶藻弧菌、鲨鱼弧菌和轮虫弧菌杀菌作用最强,最小杀菌质量浓度为256mg/L。质量浓度为512mg/L的黄连素溶液分别在20、40、60、80、100、121℃处理下作用30min,对美人鱼发光杆菌美人鱼亚种的杀菌率均超过99%,将20、60、100℃处理的黄连素溶液于室温下避光存储35d,对指示菌的杀菌率依然大于99%,显示其良好的药物稳定性。金属离子的影响试验也证实,水环境中的Na+、Mg2+、Ca2+、K^+等离子对黄连素的杀菌效果无显著影响。因此,黄连素适宜作为防治水产动物细菌性疾病的临床药物。  相似文献   
92.
Capture‐based aquaculture (CBA) is a strategy to capture wild aquatic organisms for rearing. The most iconic species produced under this scheme are bluefin tunas. In Mexico, CBA of this species is developed with Pacific bluefin tunas (PBFT). The parametrization of a biological production function able to describe biomass dynamics during the production cycle is one of the strategies that can help optimize production. The objective of this study was to explain biomass dynamics in capture‐based Pacific Bluefin tuna aquaculture in Mexican waters through parameterization of a growth and survival model. This study also assessed the impact of uncertain intrinsic CBA variables (i.e. seed weight, number of stocked individuals and sea surface temperature [SST] variability). The model was parameterized with production records of 47 net pens in two production sites (an offshore and an inshore facility) during three cycles. The results suggested that production performance was related to SST given that this factor affected survival, mainly during the first ≈40 days after stocking. The risk analysis showed that stocking during the second half of the fishing season from June to August increased the likelihood of matching or exceeding the Key Performance Indicator (KPI) defined regarding biomass increase per pen.  相似文献   
93.
Aquaculture surpassed wild fisheries as the largest supplier of fish for human consumption in 2014 and is expected to supply the majority of seafood for future increases in demand. Marine and coastal aquaculture, collectively referred to as mariculture, currently represents just 36% of aquaculture production but is poised to expand in the decades ahead. One of the most commonly cited concerns regarding this likely expansion is ecological and socioeconomic interactions with wild‐capture fisheries. While attention has largely been drawn to high‐profile negative externalities from fed finfish and crustacean mariculture, not all marine‐based practices are equivalent. Empirical evidence for the different interactions between mariculture and wild fisheries is often sparse. While negative consequences can arise, positive synergies can also occur. By considering mariculture development in the context of fisheries interactions, we suggest that it is possible to minimize conflicts and maximize positive connections between the two sectors. We provide the first comprehensive synthesis of the interactions between mariculture and wild fisheries, characterizing the types of interactions, evaluating available empirical evidence and identifying where management (sector‐specific and cooperative) can play an important role. We highlight potential effects of mariculture on the efficiency, sustainability, and equity of seafood production and identify remaining knowledge gaps.  相似文献   
94.
As the major opportunistic pathogen to both marine animals and humans, Vibrio alginolyticus (V. alginolyticus) has caused heavy economic losses to mariculture. ssDNA aptamer VA2 targeting live V. alginolyticus was generated by systematic evolution of ligands by exponential enrichment (SELEX) technology in our previous study. In this study, we first developed aptamer (VA2)‐based enzyme‐linked apta‐sorbent assay (VA2‐ELASA) for rapid detection of mariculture pathogen V. alginolyticus. The VA2‐ELASA could achieve the rapid detection for V. alginolyticus infection with high specificity and sensitivity. The VA2‐ELASA could specifically identify V. alginolyticus, but not other non‐target bacterial strains. VA2‐ELASA could detect V. alginolyticus at the concentration of 5 × 104/ml, the incubation time short to 1 min and the incubation temperature as high as 45°C, which proved sensitivity and stability of the novel VA2‐ELASA in this study. It took less than one hour to accomplish the detection process by VA2‐ELASA. The characteristics of specificity, sensitivity and easy operation make VA2‐ELASA a novel useful technology for the rapid diagnosis of pathogen V. alginolyticus in mariculture.  相似文献   
95.
Mariculture ponds, most of which are reclaimed from coastal wetlands, have increased dramatically worldwide. However, ecological damage and compensation of these reclaimed mariculture ponds have not been assessed. A framework was presented to assess ecological damages of reclaimed pond mariculture and applied to the Qingduizi Bay, a typical pond mariculture area in the northern Yellow Sea of China. The results show that ecosystem services affected by reclaimed pond mariculture include marine capture fishery, gene resource provision, climate regulation, erosion control, waste treatment, science and education value, nutrient cycle and storage, and nursery/habitat. Among the values obtained from all services, the average score of damage severity to habitat services (0.74) was the highest. The total value of ecological damage associated with reclaimed mariculture in Qingduizi Bay was approximately 86,858.48 yuan hm?2 a?1, which is 29 times higher than the sea usage fee standard (3,000 yuan hm?2 a?1) currently implemented. Results suggest that the government should update the sea area usage fee with ecological damage compensation for reclamation mariculture and collect enough money to restore damaged marine ecosystem. Moreover, the general framework could also be transferable to other reclamation pond mariculture areas and used to examine reclamation mariculture proposals at different scales.  相似文献   
96.
根据山东省1978-1999年间海水养殖面积、产量和单产统计资料,解析了海水养殖业发展过程中,养殖产量受养殖面积增加和养殖单产水平变化的影响程度,研究表明:(1)近20斫来,山东省海水养殖单产提高幅度很小,对海水养殖产量增长的贡献率较低;(2)养殖面积保持较高的增长率,尤其是90年代中期以后,养殖面积的快速增长与养殖单产的急剧下降形成鲜明对比,外延性扩大再生产比例过高,内涵性扩大再生产比例过低是过去20年山东省海水养殖业发展的主要特征,可以认为不断提高养殖技术是实现山东省海水养殖业可持续发展的关键所在。  相似文献   
97.
大型海水网箱设计中的材料选择   总被引:3,自引:0,他引:3  
报道了大型海水养殖网箱设计中要考虑的海况因素和材料选择,包括框架材料、网衣材料、锚泊固定等材料性能,评述了网箱系统三大要素的重要性。  相似文献   
98.
海水鱼类细菌性疾病病原及其检测、疫苗研究概况   总被引:8,自引:1,他引:8  
概述了海水鱼类常见细菌性疾病包括弧菌病、冬季溃疡病、巴斯德氏菌病、疖病、海水屈挠杆菌病、假单胞菌病、链球菌病、细菌性肾病的病原研究及其检测、疫苗研究概况,为及时了解当前细菌性疾病的研究进展及发展趋势以采取更有效的措施防治疾病提供参考依据。  相似文献   
99.
海洋生物寡糖是一类新型寡糖,它们往往具有特殊的化学结构,带有独特的活性基团,因此具有一些特殊生物活性。研究表明,把它作为营养素添加到水产养殖的饲料里,可以提高养殖类海洋无脊椎动物的免疫机能,从而提高抗病性。这为解决当前日益严重的养殖海参病害和虾病害提供了一条新的途经。  相似文献   
100.
根据2012年11月和2013年2、5、8月对福建三沙湾盐田港养殖海域进行4个季节调查获得的pH、总碱度(TA)、表层水温、盐度、溶氧和溶解无机碳(DIC)以及叶绿素a等基础数据,估算该区域表层海水溶解无机碳体系各分量的浓度、pCO2和海-气界面CO2交换通量,并对影响因素进行分析.结果表明,盐田港表层海水4个季节的DIC、HCO3、CO32--和CO2浓度分别为955~1 957.08、905.08 ~1 848.13、10.14~124.78和11.48 ~ 39.78 μmol/L,不同季节之间差异极显著(P<0.01).盐田港表层海水中的pCO2在一年中的变化范围为391.27 ~1 200.49 μatm,海-气界面CO2交换通量全年的范围为0.25 ~ 6.93 μmo1/(m2·d),表现为大气CO2的弱源.盐田港海-气界面CO2交换通量不同季节的差异极显著(P<0.01),在不同站位之间的差异显著(P<0.05).秋、春季的碳通量最高,夏季碳通量最低,冬季显著低于秋季,但与春季差异不显著.分析表明,水文要素和生物要素等是影响盐田港表层海水中pCO2和海-气界面CO2交换通量的重要生态因子,其中,大型海藻的栽培活动有利于该养殖海域对大气CO2的吸收.  相似文献   
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