基于多元目标的水利风景区开发规划引导性研究

新时期,在强调水资源可持续利用的总体战略目标下,水利事业已将水土资源的生态保护、娱乐利用、旅游观光作为发展方向和任务之一,把水利风景区的开发建设纳入了重要工作内容。水利风景区的开发目标具有多元特点,其规划具有很强的综合性和多重复合的跨学科特征,是水利风景旅游事业发展面临的重要课题。在阐述水利风景区开发的多元目标基础上,对其科学规划的意义、原则、编制要求及导则等方面进行研究,并明确提出基于水资源保护、自然与景观资源保护、生态环境修复等多元目标的水利风景区规划引导整体框架。     

昆山明镜荡自然河湖型水利风景区建设与管理模式探讨

介绍昆山明镜荡水利风景区建设规划、管理和发展等情况,为自然河湖型水利风景区的建设与发展提供借鉴。昆山明镜荡水利风景区位于昆山市锦溪镇,总面积约32km2,其中水域总面积达10.78km2。在南部水乡岸线整治初期,水工程建设考虑了水利景观建设,营造整体生态景观,提高水工程的审美价值。通过景区内锦溪现代农业生态园,将都市现代农业引入到水利风景区旅游中。将汪洋湖、明镜荡、长白荡、陈墓荡等纳入生态保护工作范围,拆除养殖围网,种植水生植物;迁离污染比较严重的企业。在湖泊岸线整治后的堆土表面种植绿化植物或铺设草垫;堤防护岸采用格宾网、自然护坡等形式。自然河湖型水利风景区的建设要重点突出水工程景观营造、水生态保护与修复。在落实景区规划的同时,要注重水资源保护规划、水土保持规划等专项同步编制;水文化展示馆要考虑游客的互动参与,增加知识性、互动性、趣味性和艺术性。     

基于水文化的巴城湖水利风景区规划探析

水文化是城市水利风景区的灵魂,也是提升城市水利风景区品质和丰富其内涵的必要途径。近年来,各地大力开展水利风景区建设,凸显地域特色的水文化建设已被视为水利风景区规划的首要内容。为了阐明水文化理念对水利风景区规划的重要性,探究水利风景区规划梳理和运用水文化资源,通过水利风景区规划技术手段传承水文化,基于当前水利风景区规划建设中存在的问题,以江苏昆山巴城湖水利风景区为例进行了以下研究:(1)在水文化与水利风景区的总体认知背景下,梳理巴城水文化资源,探究如何挖掘水文化资源价值;(2)从水文化资源保护和旅游项目内涵表现方面分析了巴城湖水利风景区规划困境;(3)基于巴城水文化资源布局和发展脉络,确定规划定位和和规划布局;(4)以湖城共生、水乡共融为目标,提出"红色科教、绿色体验、蓝色休闲、金色品质"四大主题旅游产品,以传承"水利文化、水乡文化、水城文化、水蟹文化"四大水文化精髓。     

冶力关国家水利风景区旅游环境质量评价研究

旅游环境质量的好坏直接影响水利风景区水资源持续利用、水利工程安全、水生态环境保护、水文化传播甚至整个风景区的生存与发展,对旅游环境质量进行科学、全面的评价成为管理水利风景区的重要手段。通过运用层次分析法与模糊数学方法相结合的模糊综合评判方法,在构建水利风景区旅游环境质量评价指标体系的基础上,对冶力关国家水利风景区进行了评价,评价结果表明旅游环境总体较好,其中自然生态环境"很好",旅游资源和服务环境"较好",但水利工程特性、社会环境和信息环境等3大类环境评价结果为"一般"。从增加旅游活动的参与性、加强旅游服务软环境的建设、建立并完善旅游信息系统和注重挖掘水文化等方面针对性地提出了冶力关水利风景区旅游环境管理的建议,旨在保障其健康持续发展。     

冶力关国家水利风景区旅游环境质量评价研究

旅游环境质量的好坏直接影响水利风景区水资源持续利用、水利工程安全、水生态环境保护、水文化传播甚至整个风景区的生存与发展,对旅游环境质量进行科学、全面的评价成为管理水利风景区的重要手段。通过运用层次分析法与模糊数学方法相结合的模糊综合评判方法,在构建水利风景区旅游环境质量评价指标体系的基础上,对冶力关国家水利风景区进行了评价,评价结果表明旅游环境总体较好,其中自然生态环境＂很好＂,旅游资源和服务环境＂较好＂,但水利工程特性、社会环境和信息环境等3大类环境评价结果为＂一般＂。从增加旅游活动的参与性、加强旅游服     

水利渔业健康发展问题探讨

水利渔业在产品提供、环境净化、生态支持、生物多样性的产生与维持、休闲娱乐与文化功能等方面有特殊的生态系统服务功能;在水利综合经营、水资源优化利用、水管单位生存发展及社会稳定等方面有特殊的作用.发展水利渔业,应以科学发展观为指导,将资源节约、环境友好及可持续发展等理念落实到水利渔业健康发展之中去,强化行业管理部门的宏观指导,畅通水利渔业资金投入渠道,以市场需求为导向,以质量和效益为中心,以生态保育为前提,实现水资源和生物资源的可持续利用,以水利渔业的健康发展支持水资源的持续利用.     

介绍一种节约型水产养殖模式

"十一五"规划建议把节约资源作为基本国策,号召发展循环经济,保护生态环境,加快建设资源节约型、环境友好型社会.本文介绍一种符合我国水产养殖业未来发展要求的节约型水产养殖模式,它具有较高的推广价值和发展前景,在现阶段水产养殖生产中,节约型水产养殖模式能够实现土地资源、水资源、饵料、药物等的节约和合理利用,是一种"资源节约、环境友好"型健康养殖模式.     

海洋动物生态学家邓景耀教授谈“两岛一湾”开发的意义

“两岛一湾”开发规划的实施,不但对渤海,乃至全国的海湾和近海渔业开发均具有重要的意义.邓景耀教授认为,在诸如多元增养殖的环境改造、最佳环境     

关于湖北水库水生态环境建设的探讨

围绕水库水生态环境建设,从遵循客观规律,让河道回归自然;划定三圈蓝线,保护水库水生态安全;加强水利风景区建设,打造水库生态环境靓点等几个方面进行了探讨.并提出了保证大力建设水生态环境的思想、政策、体制和行动上的措施.     

试论黄河三角洲生态农牧化高质量发展的策略与途径

黄河三角洲自然资源丰富、生态系统独特,其生态保护和高质量发展已上升为国家战略.在资源环境约束趋紧、生态系统退化的严峻形势下,黄河三角洲生态农牧化是实现其高质量发展的重要方式之一.为构建绿色、低碳、循环的黄河三角洲生态农牧化新模式,本研究分析了其高质量发展面临的问题,提出其发展的理念和目标.在此基础上,针对性地提出多元驱...     

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 hormone (GH) and reproduction: a review

Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations.     

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).     

Evaluation of a Fast Method Based on the Presence of Two Restriction Sites in the Mitochondrial ND5 (mt ND5) Gene for the Identification of Scomber Species

The purpose of this work was to evaluate the suitability of a method based on the presence of two restriction sites (for Hae III and Hindf I) in the mitochondrial NADH dehydrogenase subunit 5 (mt ND5) gene to identify Scomber species. The evaluation was performed on 144 reference and market samples by sequencing of the entire 505-bp fragment of the mt ND5 gene and of a 464-bp fragment of the Kocher fragment of the cytochrome b gene (mt Cytb). Sequence analysis of any of the two fragments allows the identification of each of the four Scomber species, but S. japonicus and S. colias had the same restriction sites at the ND5 amplicon and would not have been differentiated by this analysis. Similarly, loss of the Hae III site in some S. scombrus individuals would have misidentified them as not being Scomber. All the market products were correctly labeled except one acquired in Spain labeled as originating in the Atlantic and containing S. japonicus.     

Imported ornamental fish are colonized with antibiotic‐resistant bacteria

There has been growing concern about the overuse of antibiotics in the ornamental fish industry and its possible effect on the increasing drug resistance in both commensal and pathogenic organisms in these fish. The aim of this study was to carry out an assessment of the diversity of bacteria, including pathogens, in ornamental fish species imported into North America and to assess their antibiotic resistance. Kidney samples were collected from 32 freshwater ornamental fish of various species, which arrived to an importing facility in Portland, Oregon from Colombia, Singapore and Florida. Sixty‐four unique bacterial colonies were isolated and identified by PCR using bacterial 16S primers and DNA sequencing. Multiple isolates were identified as bacteria with potential to cause disease in both fish and humans. The antibiotic resistance profile of each isolate was performed for nine different antibiotics. Among them, cefotaxime (16% resistance among isolates) was the antibiotic associated with more activity, while the least active was tetracycline (77% resistant). Knowing information about the diversity of bacteria in imported ornamental fish, as well as the resistance profiles for the bacteria will be useful in more effectively treating clinical infected fish, and also potential zoonoses in the future.     

Effect of iodophor disinfection of non‐hardened Salmo trutta eggs on their bacterial and fungus load

This study investigated the efficiency of iodophor disinfection (135 ppm active iodine for 15–30 min) of non‐hardened Salmo trutta eggs against different groups of bacteria and against fungus. Egg samples were taken from non‐disinfected and from disinfected eggs, microorganisms were cultured on specific nutrient media and their mass was measured by turbidimetric methods. Bacteria and fungus mass of non‐hardened eggs could be reduced but not eliminated by iodophor disinfection with 135 ppm active iodine for 15 min. The extent of reduction was 47–65% (Experiment 1). The efficiency of disinfection increased with disinfection time as the reduction in bacteria and fungus mass was 40–55% after 15 min and 58–74% after 30 min (Experiment 2). Disinfection efficiency of iodophor solution diluted in water (reduction 49–57%) and of iodophor solution diluted in sodium chloride solution iso‐osmolar to the oocytes (reduction 52–61%) was similar (Experiment 3). The reduction in bacteria and fungus mass was persistent as it was 39–72% lower in embryos deriving from disinfected eggs than in embryos deriving from non‐disinfected ones (Experiment 4). In conclusion, the tested disinfection method is inadequate to eliminate pathogens completely but it could positively influence immune defence of eggs and embryos.     

Nitrogenous waste excretion and accumulation of urea and ammonia inChalcalburnus tarichi (Cyprinidae), endemic to the extremely alkaline Lake Van (Eastern Turkey)

The endemic, anadromous cyprinidChalcalburnus tarichi is the only fish species known to occur in alkaline Lake Van (Eastern Anatolia, Turkey). EightC. tarichi were maintained individually in Lake Van water (17 – 19°C; pH 9.8; 153 mEq·I^–1 total alkalinity; 22 total salinity) and tank water samples analyzed for 24 h in 2 to 4 h intervals. At zero time, < 1µM ammonia was present and urea was undetectable in the tank water; at 24 h, total ammonia and urea made up 114±32 and 35±25µM, respectively. Over the experimental period, ammonia-N and urea-N excretion averaged 1041±494 and 607±169moles·kg^–1 fish·h^–1, respectively. The extent of urea excretion was highly variable between specimens. Uric acid excretion was not detectable.Urea was present at high concentrations in all tissues and plasma (25 – 35moles·g^–1·ml^–1) of freshly caughtC. tarichi; total ammonia content of the tissues was by a factor of 1.9 (liver) to 3.0 (brain) lower. High arginase activity (2.4±0.2 U·min^–1·g^–1) was detected in the liver ofC. tarichi but ornithine carbamoylphosphate transferase, a key enzyme of the ornithine-urea-cycle, was absent. Ureagenesis is likely through degradation of arginine and/or uricolysis. High glutamine synthetase activity (11±0.6 U·min^–1·g^–1) and low ammonia content in brain suggest that, like other teleosts,C. tarichi has an efficient ammonia detoxification in the brain, but in no other tissue.Nitrogenous waste excretion at alkaline pH is discussed. The ability ofC. tarichi to excrete high levels of ammonia at extremely alkaline pH is unique among teleosts studied so far. The mechanism of ammonia excretion under Lake Van conditions remains to be elucidated.