南极半岛邻近海域南极大磷虾(Euphausia superba Dana)的数量组成和分布

根据2010年1月23日?2月13日在南极南设得兰群岛和南奥克尼群岛邻近海域渔场采集的南极大磷虾(Euphausia superba Dana)样品,分析了南极大磷虾数量、个体体长分布和发育期组成等种群结构特点。样品由330 μm和500 μm浮游生物网垂直拖网和表层水平拖网两种采集方式所获。结果显示,采集样中,南奥克尼群岛水域的南极大磷虾平均密度为1.92 ind/m3,高于南设得兰群岛水域的相应值(0.35 ind/m3);出现的南极大磷虾个体发育期包括CI至CIII期原蚤状幼体、FI至FIV期和FVI期蚤状幼体、未成体、成体(包括雌体和雄体);各发育期个体中,原蚤状幼体数量较多;原蚤状幼体、蚤状幼体、未成体及成体的体长范围(平均体长)分别为1.76–4.96 mm (3.48 mm)、3.95–14.80 mm (5.96 mm)、16.87–39.85 mm (36.10 mm)、40.00–58.96 mm (43.94 mm)。CIII期原蚤状幼体和FI期蚤状幼体的生长率较高。推测,南奥克尼群岛水域南极大磷虾生殖季节始于9月末,集中出现在12月中上旬;而南设得兰群岛生殖季节应早于上述水域。比较两种采集方式,南极大磷虾在水平网中的出现频率和个体出现数量均高于垂直网采集样的相应值,建议传统垂直拖网与水平拖网两种采样方式有效结合,可促进更全面了解大磷虾水平分布和种群结构特点。     

山东半岛沿海渔民转产转业的路径选择

近年来,由于我国近海渔业资源不足与捕捞力量过剩之间的矛盾,山东半岛沿海渔民转产转业问题越来越受到关注。文章依据山东半岛渔业及相关产业的发展特点和规律,对山东半岛沿海渔民转产转业的路径进行探讨和分析,提出以海水养殖业、水产加工业、滨海旅游业、休闲渔业等传统和新兴产业为主的路径选择。同时结合实际提出了实现山东半岛渔民转产转业的四项关键措施。     

Genetic Analysis of Dobrava–Belgrade Virus from Western Serbia – A Newly Detected Focus in the Balkan Peninsula

Dobrava–Belgrade virus (DOBV) is a hantavirus species that causes the most severe form of haemorrhagic fever with renal syndrome (HFRS) in Europe. DOBV has been detected in three Apodemus rodents: A. flavicollis, A. agrarius and A. ponticus. These emerging viruses appear throughout the Balkan Peninsula including Serbia as its central part. In this study, we examined the seroprevalence, molecular epidemiology and phylogenetics of DOBV from A. flavicollis captured at six Serbian localities. Furthermore, we applied microsatellite typing of host animal genome to analyse the role of host kinship in DOBV animal transmission. The overall IgG seropositivity rate over 3 years (2008–2010) was 11.9% (22/185). All seropositive samples were subjected to RT‐PCR and DNA sequencing for S and L genome segments (pos. 291–1079 nt and 2999–3316 nt, respectively). DOBV was genetically detected in three samples from mountain Tara in western Serbia, a newly detected DOBV focus in the Balkans. No sequence data from human cases from Serbia are available for the studied period. However, collected DOBV isolates in this work phylogenetically clustered together with isolates from Serbian human cases dating from 2002, with 1.9% nucleotide divergence. We determined the level of kinship between seropositive and seronegative animal groups and found no significant difference, suggesting that horizontal virus transmission in the studied population was the same within and among the hatches. Our findings are the first genetic detection of DOBV in rodents in Serbia. We confirm wide and continuous hantavirus presence in the examined parts of the Balkans, underlying the necessity of continual monitoring of hantavirus circulation in A. flavicollis.     

Contribution of Mycorrhizae to Early Growth and Phosphorus Uptake by a Neotropical Palm

Arbuscular mycorrhizal fungi (AMF) can act as an extension of the root system of their host plants. In Desmoncus orthacanthos Martius (Arecaceae), which has thick and unbranched roots (i.e., magnolioid roots) and low densities of root hairs, this association may be essential to reach a maximum growth with minimum fertilizers. This is important because of the potential in the south of Mexico to use D. orthacanthos' shoots as a raw material to build handcrafts. To evaluate the effect of arbuscular mycorrhizae on phosphorus (P) uptake and initial growth of D. orthacanthos seedlings, a 160-day bi-factorial experiment was carried out in which plants were subject to one of two levels of mycorrhizal colonization (with or without) and one of three levels of P substrate addition (4, 12, and 24 ppm). Our results show that total dry weight (DW) and leaf area (LA) responded significantly to P addition but not to mycorrhizal colonization. Phosphorus concentration in plant tissues (Pt) was increased by both factors (mycorrhizae and P addition). Mycorrhizae increased relative growth rate (RGR) at low P level. Our results indicate that AMF play an important role in early growth and P uptake by D. orthacanthos seedlings; therefore, the AMF must be considered in plantations of this potentially economically important palm.     

山东半岛北岸采砂和海蚀问题与对策

就山东半岛北岸登州浅滩和莱州浅滩采砂的两个案例所反映出的环境与资源、社会与法律方面的问题进行了思索和探讨,对合理开发建筑用砂、注意提取其中蕴藏的贵重矿物、侵蚀海岸养护措施、公正执法、以及半岛北岸今后采砂业的出路提出了建议.     

Risk screening of non‐native freshwater fishes in Croatia and Slovenia using the Fish Invasiveness Screening Kit

The Fish Invasiveness Screening Kit (FISK) version 2 was used to assess the invasiveness potential of 40 introduced and translocated freshwater fish species to Croatia and Slovenia. Based on a priori classification of invasiveness, receiver operating characteristic analysis of FISK scores from two independent assessors resulted in a statistically significant calibration threshold of 11.75. This indicated that FISK was able to discriminate reliably between non‐native species likely to pose a high risk of being invasive and those likely to pose a medium or low risk of invasiveness. Seven species were categorised as ‘medium risk’ and the other 33 as ‘high risk’, whereas no species was categorised as ‘low risk’. The two highest scoring species were European catfish Silurus glanis and North African catfish Clarias gariepinus. Mean scores for all species classified a priori as invasive were ranked as ‘high risk’ sensu lato and fell into the ‘moderately high risk’ subcategory. FISK proved to be a valid tool for assessing the risks posed by non‐native fishes in Croatia and Slovenia. For this reason, it can be adopted as a reliable tool for the prevention of new translocations or introductions of potentially invasive species in the risk assessment area, as well as to assist in decisions regarding future management (i.e. monitoring, control and eradication) and conservation strategies.     

山东半岛南部近岸海域蟹类群落结构特征

根据使用单船底拖网进行2014年8月和10月、2015年2月和5月4个航次的调查数据,对山东半岛南部近岸海域蟹类种类组成、时空分布、优势种、物种多样性等群落结构特征进行了研究。结果显示,4次调查共捕获蟹类15种,隶属于7科12属,其中三疣梭子蟹(Portunus trituberculatus)、日本蟳(Charybdis japonica)是主要经济种类,其余多为小型饵料型蟹类;双斑蟳(C.bimaculata)在4个季节中皆为优势种,三疣梭子蟹在8月和10月航次为优势种,优势种季节更替明显;生物量季节变化明显,春季时较低,在夏季达到峰值,夏季到冬季呈降低趋势;蟹类群落物种多样性指数(H′)变化范围为0.32~0.53,均匀度指数(J′)变化范围为0.23~0.37,丰富度指数(D)变化范围为0.32~0.55,其中物种多样性指数与丰富度指数季节变化明显,均匀度指数季节变化不明显;多元统计分析结果表明,山东半岛南部近岸海域4季节蟹类群落结构均可以划分为西南部海域组、东北部远岸海域组和西北部近岸海域组3个组群,季节间组群站位组成变化明显,群落结构不稳定。研究表明:1)山东半岛南部近岸海域蟹类以小型饵料型蟹类为主,蟹类多样性水平较低,优势种更替明显,蟹类群落不稳定;2)山东半岛南部近岸海域蟹类群落划分较为明显,特征种主要为双斑蟳、泥脚隆背蟹(Carcinoplax vestita)等小型饵料型蟹类。     

Loss of Ostracoda biodiversity in Western Mediterranean wetlands

• 1. The coastal area of Valencia (Spain) in the Western Mediterranean is rich in freshwater and brackish wetlands. These areas are mostly protected for bird conservation but are also highly affected by human impacts. Six shallow lakes located in Ramsar wetland sites of this area were studied in order to assess past and present ostracod biodiversity and relate it to the status of the lakes, taking into consideration the indicator value of these easily fossilizable crustaceans.
• 2. In all the wetlands studied, ostracod taphocoenoses showed much higher species richness than the corresponding biocoenoses. This is expected from the time accumulative character of the taphocoenosis, but the trend is clearly evident in the most disturbed sites which indicated loss of ostracod diversity owing to human impacts.
• 3. By considering the ecology of most frequent species, multivariate ordination of both tapho- and biocoenoses showed trends within and between lakes in their limnological status, which were related mainly to water chemistry, and also to temporality and eutrophication to a certain extent. Some lakes have apparently lost most of their past ostracod community owing to an increasing trophic status in some cases and to modifications of the hydrological regime in others.

Copyright © 2007 John Wiley & Sons, Ltd.     

雷州半岛前沿恶劣潮间滩涂红树林造林树种的选择

就雷州半岛典型前沿潮间滩涂的红树植物种类、分布及土壤、水文因子等进行了全面的调查,在附城镇的前沿恶劣滩涂开展了红树植物的移植试验。移植2年后,通过各树种的成活率、生长量和抗逆性的比较,筛选出抗逆红树植物——白骨壤和抗逆速生红树植物——无瓣海桑,二者的造林成活率均高于70%。研究结果为广东省沿海红树林防护林的构建提供理论与技术支持。     

城市和工业化对山东半岛农田系统的影响

[目的]对城市和工业化对山东半岛农田系统的影响进行研究。[方法]以山东半岛为研究区,通过遥感解译、数据空间分析、社会统计数据分析,了解城市和工业化对农田系统的影响。[结果]山东半岛的荒地面积在研究时段先减后增,耕地面积逐渐减少,而果园和林地的面积逐年增加。造成这种差异趋势的主要原因是政府政策和农民利益最大化等因素共同作用的结果。同时,工业和城市化发展使用于农业生产的化肥施用量和农业机械总动力逐渐增加。这种发展趋势对环境、工业和城市化带来了不同影响。[结论]为了社会经济和环境的和谐发展,政府应制定更多的政策来协调社会经济和环境的发展。