Natural diet of grapsoid crab <Emphasis Type="Italic">Plagusia dentipes</Emphasis> de Haan (Decapoda: Brachyura: Plagusiidae) in Tateyama Bay,Japan

The natural diet of Plagusia dentipes de Haan was studied in Tateyama Bay, Japan, between June 2004 and May 2005. A total of 389 specimens were collected for analysis of stomach content during the period, with sizes ranging between 7.1 and 63.1 mm in carapace width. The major dietary item was rhodophycean algae (mostly articulated coralline algae), which was ingested by 91.8% of the crabs and accounted on average for 55.6% (points) of the volume of stomach contents. Chlorophycean algae (mostly Ulvaceae, 39.1% and 8.1 points) and crustaceans (mostly amphipods, 38% and 3 points) came next in feeding frequency and volume. Minor dietary items also included other algae such as Phaeophyceae and animals such as mollusks (bivalves, gastropods), annelids (polychaetes), other crustaceans (caprellids, isopods), and echinoids. Significant seasonal dietary differences were observed and, in general, the diet in spring contained more food items, particularly more animals, compared to other seasons. Feeding of Rhodophyceae was highest and lowest in winter and summer, respectively. The total volume of food consumed was also lowest in summer and likely reflected reduced availability of the main food item in this season. There were no differences in dietary items between male and female crabs. In conclusion. P. dentipes is a primarily herbivorous crab with incidental or opportunistic feeding on animal items, and it is suggested that seasonal shifts in consumption may be related to growth, molting, and reproductive activity.     

Coralligenous assemblages along their geographical distribution: Testing of concepts and implications for management

• 1. The coralligenous habitat was studied at the large Mediterranean scale, by applying a standardized, non‐destructive photo‐sampling protocol, developed in the framework of the CIGESMED project.
• 2. The results provided evidence to support the following statements: (a) the assemblage pattern is not homogeneously distributed across the four Mediterranean ecoregions studied (biotic gradients hypothesis); and (b) the assemblage pattern does not change significantly when the information is aggregated to higher taxonomic levels (taxonomic sufficiency hypothesis).
• 3. Surrogate taxonomic categories higher than species, such as genus and family, can be used to reveal the multivariate pattern of the coralligenous assemblages.
• 4. Although preliminary at the pan‐Mediterranean scale, these outcomes set the scene for future comparisons as more data sets become available but also for comparisons between taxonomic and functional patterns.

     

The introduction of the European bitterling (Rhodeus amarus) to west and central Europe

The European bitterling is considered to be a native species over much of its present range in Europe. A dramatic decline in its abundance from 1960 to 1980 in west and central Europe, attributed to aquatic pollution, led to the establishment of stringent national and international regulations for protection of the species. Here, we review the evidence that until AD 1100 the bitterling was restricted to the Ponto‐Caspian and Aegean regions (south‐eastern Europe and adjacent regions of Asia Minor) and only expanded into its present range during the 19th century. The earliest records of bitterling in west and central Europe are from regions where carp cultivation was common and the bitterling appears to have spread into this region in association with the gradual expansion of carp cultivation. After an initial period of expansion, between approximately 1150 and 1560 in regions with carp cultivation, the species virtually disappeared from Europe during the coldest period of the Little Ice Age. Bitterling reappeared at the end of the 18th century, initially in historical centres of carp cultivation, and was again abundant and widespread in Europe by around 1850. Its reappearance appears to have been through expansion of refuge populations as well as new invasions. The decline in abundance of bitterling during the period 1960–80 in west and central Europe appears not only to have been caused by pollution, as is generally believed, but may also be correlated with low spring temperatures. From approximately 1980 onwards the European bitterling once again expanded its distribution in many parts of Europe, particularly in eastern Europe. This recent expansion may be due to a combination of factors, including a rise in ambient temperature coupled with an increase in anthropogenic dispersal and changes to aquatic habitats favourable to bitterling. Thus, the bitterling, which is legally protected in Europe at a national and international level as an endangered indigenous species, is actually an invasive species and a parasite of freshwater mussels. Its current expansion in distribution could pose a hazard to freshwater mussel populations in regions where they are already threatened.     

使用漂白粉改善对虾池水环境的研究

对漂白粉的杀菌效果，对对虾毒性、对单胞藻和虾池水环境因子的影响进行了试验研究。池水有效氛浓度为０．３～０．５×１０（－６），不会对对虾和池内单胞藻造成危害，并可使氨氮含量降低，ＰＨ值增加，对溶解氧、化学耗氧量等无明显影响。治疗虾病时，先使用漂白粉，然后投喂药饵，可取得较好效果。     

阔叶丰花草对茄科作物的化感效应

为探明入侵植物阔叶丰花草对茄科作物种子萌发和幼苗生长的影响,采用种子萌发与生物测定法,测定比较了阔叶丰花草不同浓度水提液处理番茄、茄子和辣椒种子的萌发率、幼苗的根长及茎长。结果表明：番茄和茄子的发芽速度指数随处理浓度上升而显著降低;番茄种子的萌发率略低于对照,均在93．33％以上;茄子和辣椒种子的萌发率均随水提液浓度的上升而降低,14 d 时分别在70％以上和66．67％以上;各浓度水提液番茄和茄子的根长显著低于对照,辣椒除高浓度外,根长均长于对照;培养7 d 时番茄的茎长短于对照,14 d 时均长于对照。结论：阔叶丰花草对番茄的综合化感效应表现为抑制作用;低浓度的水提液对茄子综合化感效应表现为促进作用,高浓度为抑制作用;辣椒则表现为抑制转变为促进,表现出一定的适应性。     

Changes in Soil Biota Resulting from Growth of the Invasive Weed,Ambrosia artemisiifolia L.（Compositae）, Enhance Its Success and Reduce Growth of Co-Occurring Plants

Exotic plant invasion presents a serious threat to native ecosystem structure and function. Little is known about the role of soil microbial communities in facilitating or resisting the spread of invasive plants into native communities. The purpose of this research is to understand how the invasive annual plant Ambrosia artemisiifolia L. facilitates its competition capacity through changing the structure and function of soil microbial communities. The soil characteristics of different areas invaded by A. artemisiifolia were examined. Greenhouse experiments were designed to assess the effect of A. artemisiifolia invasion-induced changes of soil biota on co-occurring plant growth, and on the interactions between A. artemisiifolia and three co-occurring plant species. The results showed that the soil organic C content was the highest in heavily invaded sites, the lowest in native plant sites, and intermediate in newly invaded sites. Soil available N, P and K concentrations in heavily invaded site were 2.4, 1.9 and 1.7 times higher than those in native plant soil, respectively. Soil pH decreased as A. artemisiifolia invasion intensity increased, and was lower in invaded sites（heavily invaded and newly invaded） than in native plant sites. The soil microbial community structure was clearly separated in the three types of sites, and A. artemisiifolia invasion increased anaerobe, sulfate-reducing bacteria and actinomycete abundance. Soil biota of invaded sites inhibits growth of co-occurring plants（Galinsoga parvifloraCav., Medicago sativa L. and Setaria plicata（Lam.） T. Cooke.） compared to soil biota from un-invaded sites, but facilitates A. artemisiifolia growth and competition with co-occurring plants. A. artemisiifolia biomass was 50-130% greater when competing with three co-occurring plants, compared to single-species competition only（invasion by A. artemisiifolia alone）, in heavily invaded soil. Results of the present study indicated that A. artemisiifolia invasion alters the soil microbial communit     

喜旱莲子草的利用现状及展望

喜旱莲子草[Alternanthera philoxeroides(Mart.)Griseb]在农业上可以作为饲料、肥料、栽培食用菌、制作沼气,并用于水稻育种;在污染治理上的主要应用在净化水体、富集重金属上;在医药上主要应用在抑菌、抗病毒、护肝、抗肿瘤上。笔者综述了近年来国内外对喜旱莲子草利用和研究的进展,并对其未来利用进行了展望。     

原生动物在水质净化过程中的应用与发展

原生动物是水质净化过程中重要的组成部分,研究原生动物在水质净化方面的应用与发展已成为研究热点。首先阐述了原生动物的概念、营养类型、分类和研究目的,并在此基础上分析了原生动物在水质净化过程中的生态演替、指示作用、预测出水水质及强化净化效果等方面的特性;最后从原生动物种群动态与水质变化的相互关系、原生动物污泥减量化效果和食藻类原生动物在治理蓝藻水华中的应用等方面分析了原生动物在水质净化领域的研究方向。     

狐尾藻在养殖污水净化中的作用原理及相关应用进展

我国畜禽养殖污染问题日益严峻,传统的生物工程处理技术虽取得较好效果,但仍存在投资成本高、氮磷去除效果不佳等问题,且其副产物又有二次污染的风险。近年来,利用狐尾藻处理养殖污水较好地解决了上述问题。本文就近年来狐尾藻处理养殖污水及其饲料化、肥料化等资源化利用进行综述,主要介绍了狐尾藻的生物学特征及生长条件,其在养殖污水中氮磷去除、有机污染物的降解及重金属吸附方面的作用原理、应用方式和效果,并对其应用存在的不足及未来研究方向进行展望,以期为狐尾藻在养殖污水上的应用提供参考。     

Cytologic,histologic, microbiologic,and electron microscopic characterization of a canine Prototheca wickerhamii infection

An adult dog was presented for chronic cough and a recent development of ulcerated, erythematous nares with nasal discharge. Cytology of enlarged peripheral lymph nodes revealed many intracellular and extracellular organisms. These round or rarely oval organisms measured approximately 5-9 µm in diameter and frequently contained several globular structures, ranging from deeply basophilic to magenta. A thin, clear halo was present. Smaller 1-2 µm, magenta forms were also observed. Fungal culture yielded small, wet, raised, irregularly shaped, white to pale tan colonies. Microbiologic staining of cultured material revealed features suggestive of algae. Histopathology of the lymph nodes revealed marked granulomatous inflammation with intralesional algal organisms suggestive of Prototheca. Electron microscopic findings were also consistent with protothecosis. Polymerase chain reaction, followed by direct DNA sequencing, identified the organism as Prototheca wickerhamii. A brief literature review discussing protothecosis in veterinary medicine is included.