海滩互花米草生长区的综合开发与利用

正浙江省乐清湾是一个半封闭的葫芦形海湾,总滩涂面积约249 km~2,是浙江省重要的海水增养殖基地,有着丰富的生物多样性。1983年,当地沿海滩涂引进了互花米草(Spartina alterniflora)种植,在抗风消浪、保滩护岸、促淤造陆等方面,取得了很好的效果~[1]。但经过30多年的发展,互花米草在我国沿海不少地区快速扩散,形成了单一外来入侵优势群落,侵占面积已占滩涂总面积近40%,给当地自然     

优良鱼草──岸杂一号狗牙根

岸杂一号狗牙根［Cynodonlactvlon（L）Peis」，又名岸杂一号绊根草，属禾本科多年生植物，是美国用海岸狗牙根与P·互·255445狗牙根杂交培育而成的。主要分布于北纬33"以南的东部地区。我国1976年引进，现已在两广、福建等南方省份推广。该草须根细，茎圆、光滑，直径0．2～0     

不同耐盐植物人工湿地净化养殖外排水效果

为了探究不同耐盐植物对海水养殖外排水的去污效果,选取了芦苇(Phragmites australis)与互花米草(Spartina alterniflora)为湿地植物,细沙、蛭石和珊瑚石为基质,构建了2套复合垂直流人工湿地系统。对比分析了2种挺水植物的耐盐性及对海水养殖外排水中氨氮(NH_4-N)、亚硝态氮(NO_2-N)、硝态氮(NO_3-N)、高锰酸钾指数(COD_(Mn))和磷的净化效果。结果显示,芦苇耐盐度最高为20,而互花米草在盐度35以下均能正常生长,芦苇和互花米草湿地系统对NH_4-N的平均去除率分别为(85.48±0.50)%和(95.01±1.18)%,对COD_(Mn)平均去除率分别为(57.74±4.40)%和(72.84±2.64)%。互花米草湿地系统对NH_4-N和COD_(Mn)的平均去除率高于芦苇湿地,分别高9.53%和15.01%,差异性显著(P0.05)。互花米草和芦苇湿地系统对磷酸盐和总磷(TP)的去除率为40.00%~50.00%,差异性不显著(P0.05)。研究表明,在高盐胁迫下,互花米草生长状况和对无机氮(DIN)和COD_(Mn)的去除效果均优于芦苇,2种植物对磷酸盐和TP的去除率差异不明显。     

青饲料养鱼技术（连载）

四、常用鱼用青饲料品种及其栽培技术l．杂交狼尾草杂交狼尾草（PennisetumamericanumxP.purpureum图2）于1981年从美国引进我国。是美洲狼尾草（Pennisetumamericanum）和象草（P.purpureum）的杂交种，多年生。它较好地综合了父本象草高产、多年生，和母本美洲狼尾草品质好的特点，是目前最高产的牧草之一，因而近年来被广泛地种植，用于养鱼和饲养草食畜禽。（1）主要特征和生育特性杂交狼尾草是禾本科多年生草本。株高3．5米左右，高的可达4米以上。一般每株分蘖约20个左右；多次刈割利用后，分蘖可成倍增加。须根发达，根系扩展范围…     

河北省滦南湿地人工岸线生态修复

滦南湿地位于河北省唐山市滦南县沿海区域，是东亚-澳大利西亚候鸟迁飞路线上备受国际环保组织关注的省级重要湿地。但是，近年来滦南湿地及附近海域的互花米草(Spartina alterniflora Loisel)不断扩增，入侵面积呈现逐年增加的态势，造成了底栖生物的减少，破坏了鸟类的栖息生境。为此，滦南湿地生态修复项目通过采用物理法清除互花米草18.3 hm²,海堤生态化改造2.7 km。生态监测结果显示，2021年均无互花米草复长现象，取得了良好的治理效果。修复前的2020年共观测到鸟类8目17科30属46种，共计26 899只次，修复后的2021年共观测到鸟类10目19科34属57种，共计43 109只次；鸟类的栖息范围和面积均得到有效提升，鸟类的种类和数量均有明显的恢复，生态效益指标良好。     

高产优质饲草——皇草

高产优质饲草──皇草皇草（Ｋｉｎｇｇｒａｓｓ）是一种禾本科狼尾草，属多年生高产优质饲草品种，是由象草和美洲狼尾草（又名珍珠草〕杂交育成。１９８２年海南热作院从哥伦比亚引进试种成功以后，先后有两广，江西、湖南等省（区）进行引种都获得了成功。根据我所及海...     

可口革囊星虫生态繁育技术的研究

可口革囊星虫适宜在腐殖质多、底质较硬的互花米草区域生长繁殖。开展可口革囊星虫互花米草区繁养殖,可以把互花米草有害区改造成可口革囊星虫繁养殖基地,变废为宝充分保护利用海洋环境。2018年～2020年,依托福建省水产技术推广总站科技创新与推广示范项目,笔者在福建省霞浦县埕坞互花米草蔓延滩涂进行可口革囊星虫生态繁育试验,取得了较好的效果。     

互花米草与水稻远缘杂交试验初报

引种栽培了互花米草560株,栽培了水稻品种(组合)14种,进行了互花米草与水稻杂交试验。结果表明:互花米草♂×水稻♀6个品种(组合)杂交39穗,共得杂交种子115粒,杂交穗结籽率5.4%;互花米草♂×F132、F134(♀)杂交12穗,得杂交种子18粒,杂交穗结籽率2%。     

单纯投喂青科培育草亲鱼生产试验

为了降低草亲鱼的饲养成本，提高经济效益，笔者于1986～1988年和1989～1996年分两个阶段对同一批草亲鱼进行了青饲料与精饲料相结合喂养和单纯投喂青饲料生产试验，结果表明：单纯投喂青饲料培育草亲鱼不但可以降低生产成本，而且还可以提高草亲鱼成活率和催产“四率”。现将试验情况总结如下：一、材料与方法（一）鱼池条件。草亲鱼池一口，面积2．5亩，池水深1．8～2．0米，水源可靠，进出方便。（二）亲鱼放养。1985年冬季从水库中收集草鱼36尾（雌19尾、雄17尾），总重302公斤，平均个体重8．4公斤。到1996年尚剩草亲鱼25尾（雌14尾、…     

敲响生物入侵警钟保护河口滩涂贝类资源——关于遏制大米草蔓延,保护滩涂贝类资源的建议

山东省东营市河口区位于国家级自然保护区黄河三角洲自然保护区的核心区域，是国家十五规划中的黄河三角洲高效生态经济区和胜利油田的主产区。根据河口区环保局、海洋与渔业局、农业局、科技局的综合调查，在该区仙河镇至5号桩海滩出现大面积大米草。同时，该区海星贝类养殖公司二分场反映，大米草所生滩涂，鱼类贝类已濒临灭绝。据不完全统计，河口区沿海大米草主要分布于东部沿海潮间带（大海涨、落潮之间的浅海区），发展速度惊人，1993年面积仅有30m2，1996年发展到500亩，2000年发展到300亩，到2002年面积已达6000亩左右！大米草主要…     

Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean

The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna.     

Rare serotype occurrence and PFGE genotypic diversity of Streptococcus agalactiae isolated from tilapia in China

Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China.     

Growth performance,digestive enzyme activity and immune response of Japanese sea bass,Lateolabrax japonicus fed with fructooligosaccharide

In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg.     

Purification and partial characterization of GtHs (cfLH and cfFSH) from Indian walking catfish (Clarias batrachus) (L.) and development of a homologous ELISA for cfLH

Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL^?1 (1.25 ng well^?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation.     

Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection

Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg^?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality).     

Involvement of gonadal steroids in final oocyte maturation of white perch (Morone americana) and white bass (M. chrysops): in vivo and in vitro studies

Plasma estradiol-17 (E₂), testosterone (T), 17,20-dihydroxy-4-pregnen-3-one (DHP) and 17,20,21-tri-hydroxy-4-pregnen-3-one (20-S) levels were measured by radioimmunoassay (RIA) in white perch (Morone americana) and white bass (M. chrysops) that were induced to undergo final oocyte maturation (FOM) with human chorionic gonadotropin (hCG). Plasma DHP levels increased in females of both species in association with oocyte germinal vesicle migration (GVM) and germinal vesicle breakdown (GVBD) and decreased thereafter. Plasma 20-S levels also increased with oocyte GVM in white bass, but were several-fold lower than DHP levels. Circulating E₂ and T levels were greatest during GVM and GVBD in both species and decreased to low levels during oocyte hydration and ovulation. Follicles from white perch and white bass which received a priming injection of hCG in vivo, produced both DHP and 20-S in vitro after exposure to hCG and their oocytes underwent GVBD. Ovarian incubates from unprimed fish of either species produced only E₂ and T and their oocytes did not complete GVBD. Oocytes from unprimed bass, but not perch, matured when follicles were exposed to hCG in vitro. Both trilostane and cycloheximide blocked in vitro production of DHP and 20-S and oocyte GVBD by white perch follices. DHP and 20-S were equipotent inducers of FOM in the GVBD bioassay. None of several other structurally-related steroids tested were effective within a physiological range of concentrations. These results indicate a role for DHP and 20-S in the control of FOM in white perch and white bass.     

Cardiac,ventilatory and metabolic responses of two ecologically dissimilar species of fish to waterborne cyanide

Changes in heart rate, ventilatory activity and oxygen consumption were determined in trout (Salmo gairdneri) and brown bullhead catfish (Ictalurus nebulosus) during exposure to a steadily increasing concentration of waterborne cyanide selected to produce death in 8–9 hours for each species. The lethal cyanide concentration for the bullheads was an order of magnitude higher than for trout. Trout developed an immediate and gradually increasing bradycardia throughout the exposure period. Cyanide produced tachycardia in the bullhead followed by a gradual onset of bradycardia as the concentration of cyanide was raised. Pericardial injection of atropine (a muscarinic cholinergic antagonist) indicated that bradycardia in the trout was due initially to increased vagal tone but later due to the direct effect of cyanide on the heart. Hyperventilation in the trout persisted throughout the exposure period, although the rate and amplitude fluctuated and was variable between individual fish. During the last hour of exposure (highest cyanide concentration), ventilation was characterized by rapid, shallow breaths followed by a sudden respiratory arrest. The bullheads exhibited hyperventilation during the first 3 hours of exposure followed by a gradual, linear drop in ventilation rate and amplitude until death occurred. Cardiac and ventilatory responses in both species were attributed to stimulation of central and peripheral chemoreceptors by cyanide. Evidence is presented which suggests the initial response in the bullheads was due, at least in part, to gustatory stimulation by the cyanide. Oxygen consumption of the trout remained above pre-exposure levels for the majority of the test period. Oxygen consumption in the bullhead paralleled the changes in heart and ventilatory rates. Whole-body lactate levels of fingerlings of both species during cyanide exposure were measured to estimate the extent of anaerobiosis. Whole-body lactate levels were much greater in the bullheads than the trout, indicating a higher capacity for anaerobiosis, possibly due to a greater fuel supply. Overall, the trout responded to cyanide in a manner similar to that produced by environmental hypoxia whereas the bullheads experienced a gustatory stimulus which masked the hypoxia-like response.     

Protein and amino acid composition from the mantle of juvenile O ctopus vulgaris exposed to prolonged starvation

Protein and amino acid composition of the mantle of juvenile O ctopus vulgaris (Cuvier, 1797) during fasting for 27 days were determined. Average protein content of octopus mantle was of 711.19 ± 46.80 g kg^?1 DW, and it decreased with increasing fasting days. The non‐essential amino acids content was higher (486.18 ± 11.08 g kg^?1 protein) than essential amino acids (425.82 ± 9.15 g kg^?1 protein) at the start of the experiment (unstarved animals). The results suggest that the amino acid profile of the mantle where the most abundant amino acids are Arg, His, Lys, Gly, Leu and Pro could indicate a prolonged fasting condition (>20 days) or poor nutrition of O . vulgaris. This study supports the idea of using mantle for metabolic needs of starved O . vulgaris suggesting that the degradation pathway of amino acids to pyruvate and tricarboxylic acid cycle intermediates was favoured contrary to the degradation pathway of ketogenic amino acids. Special considerations should be taken concerning Thr, Ile, Ser, Ala, Asx (Asp, Asn), Glx (Glu, Gln) (because of their fast intake) and Lys and His (due to their stable contents) during a prolonged period of fasting.     

An overview of stress physiology of fish transport: changes in water quality as a function of transport duration

This study brings an integrated analysis about the relationship between water deterioration and its physiological consequences in live fish transport. The analysis was focused on the transport water and its deterioration, and physiological challenges imposed on the fish. Usual commercial handling procedures employed to mitigate fish stress during transport were discussed. Future topics of research for the establishment of safer fish transport protocols were proposed. Transport was classified into short (≤8 h) or long transport (>8 h). The main issue in short transports should be the prevention of water pH reduction, while in long transports it is the increase in ammonia. Plasma cortisol is the most employed marker for stress and is acutely elevated upon short episodes of transport, but remains elevated even in long‐transport events. Plasma glucose is perhaps a better marker for handling stress. Plasma lactate, pH, osmolality CO₂ and ions should be more often evaluated. Plasma Na⁺ and Cl^‐ are very useful markers of acidosis, due to their respective exchange for H⁺ and , for acid–base regulation. The establishment of species‐specific transport protocols should be preceded by such combined analyses of water and physiological parameters.     

Are hatchery‐reared abalone naïve of predators? Comparing the behaviours of wild and hatchery‐reared northern abalone,Haliotis kamtschatkana (Jonas, 1845)

Abalone populations have declined worldwide, generating interest in enhancement using hatchery‐reared individuals. In many cases, such restoration efforts have met with limited success due to high predator‐induced mortality rates. Furthermore, the mortality rates of outplanted hatchery abalone are often considerably higher than for wild individuals. This study uses northern abalone (Haliotis kamtschatkana) as a case study to determine whether hatchery‐reared abalone behave differently than their wild counterparts. In the field, outplanted hatchery‐reared abalone were significantly less responsive than wild abalone, in terms of number of abalone responding and intensity of response, to nearby movement and to physical contact with an inert probe. Also, when encountering a cue to which all abalone responded (a seastar predator), hatchery‐reared individuals remained subdued. Anti‐predator behavioural deficits in hatchery‐reared abalone were more pronounced in 4‐year‐old individuals than in 1‐year‐old individuals, suggesting an influence of either age or amount of time spent in the hatchery environment. These behavioural differences are expected to increase the vulnerability of hatchery‐reared abalone to predators, and are likely a major cause of their elevated predator‐induced mortality when outplanted.