Zooplankton composition of ten reservoirs in southern Brazil

The zooplankton of ten reservoirs of Sao Paulo State was analyzed as part of a larger project, Typology of Reservoirs of São Paulo State.Twenty-four genera of Rotifera, six species of Copepoda and at least nine species of Cladocera were found in samples collected on four occasions in 1979. In general, Rotifera dominated in most reservoirs, although fluctuations occurred during the year.The reservoirs were arranged in four groups, according to zooplankton density, whose range was 10 to 500 i 1^–1.The average composition of Crustacea, in number of species at any one time is comparable to those of other water bodies, being a little higher than that of Colorado lakes.The number of species of limnetic Cladocera in Brazil is between those of Holarctic Region and Tropical Asia. Ceriodaphnia cornuta and Bosminopsis deitersi, and a few species of Daphnia are typical of Brazilian zooplankton. Thermocyclops crassus is common in the southern reservoirs but T. minutus seems to be more widely distributed in Brazil. Calanoida occurred in relatively few reservoirs in São Paulo and usually one species at one time. Brachionus and Keratella were more abundant closer to the Equator then to the Tropics, where other genera seem to be more abundant.The range in size of the planktonic Crustacea is relatively small when compared to temperate lakes, being similar to that of other tropical lakes.     

Quantification of trehalose in biological samples with a conidial trehalase from the thermophilic fungus Humicola grisea var. thermoidea

The partially-purified, thermally-stable trehalase from conidia of Humicola grisea was highly specific for trehalose and was free of potentially interfering activities. The enzyme was fully stable when stored in solution at -15°C for at least 6 months. This preparation could be used to quantify trehalose from 0.05 to 1.25 mol/ml either in carbohydrate mixtures or in complex biological materials.M.J. Neves, H.F. Terenzi and J.A. Jorge are with Departmento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirao Preto, Universidade de São Paulo, 14040-901-Ribeirão Preto, São Paulo, Brazil; F.A. Leone is with Departamento de Quimica, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901-Ribeirão Preto, São Paulo, Brazil.     

Effect of carbon source on the β-glucosidase system of the thermophilic fungus Humicola grisea

H. grisea produced an extracellular -glucosidase (EC 3.2.1.21) at high activity in media supplemented with carboxymethyl cellulose (CMC) or cellobiose. Cellobiose-induced -glucosidase was insensitive to glucose repression whereas that of CMC-supplemented cultures was partially repressed. Molecular sieving revealed three main active components (M_r 50, 128 and 240 kDa). Glucose competitively inhibited -glucosidase activities with K_i values of 0.9mM and 3.3mM (extracellular) and 10.2mM and 22.6mM (cytosolic), induced in the presence of CMC or cellobiose respectively.The authors are with the Departamento de Biologia, Faculdade de Filosofia. Ciências e Letras de Ribeirão Preto, Universidade de São Paulo-14040-901 Ribeirão Preto, São Paulo, Brasil;     

Ecology and dynamics of two intertidal algal communities on the littoral of the island of São Miguel (Azores)

The intertidal benthic algal communities of two sites located on opposite coasts of São Miguel Island (Azores), were studied over a 2-year period (September 1993–September 1995). At both sites (São Roque on the south coast and São Vicente on the north), the littoral region was surveyed from the upper intertidal down to the sublittoral fringe. The survey revealed five distinct zones, with a variable degree of overlapping. The two upper zones were characterized by animals (littorinids and barnacles, respectively). Lower down, algal communities formed three distinct zones: an upper Fucus spiralis/Gelidium microdon association, a more extensive turf zone, and a belt featuring erect or frondose algae. Upper in the eulittoral, the turf was mainly monospecific, and dominated by Caulacanthus ustulatus. The lower eulittoral turf was dominated by articulated coralline algae, the associated species differing between the two sites studied. Mainly erect algae (Pterocladiella, Asparagopsis, etc.) occurred furthest down the shore and extended into the nearby shallow sublittoral. Two intertidal communities were studied at each locality: the upper eulittoral (Caulacanthus turf in São Roque and the Fucus spiralis/Gelidium microdon association at São Vicente), and the lower eulittoral (the coralline turf). The lower littoral communities had a higher algal diversity. A general pattern was observed in the seasonal variation of biomass: the lower levels exhibited the higher values in late summer/early autumn, the period in which the upper levels had the lowest standing crops. Physical factors are proposed to account for this. No significant inter-annual variations could be detected, indicating relatively stable communities, at least on a short-term basis.     

Disease in Zoanthids: dynamics in space and time

Numerous diseases in benthic marine organisms have been recognized over the last decade. Here, a new disease (pathogen unknown) is described and quantified in space and time for Palythoa caribaeorum (Cnidaria, Zoanthidea) populations on the São Paulo coast, Brazil (23° S). The degree of environmental stress (moderate vs. high), depth and temporal variation (seasons, years) on the frequency of the disease was assessed by monitoring plots at two sites: Ponta Recife (continent) and Praia Portinho (São Sebastião island), and at two depths per site (0.5–1.5 m and 2.5–4 m). The disease spread outward from within the colony in a circular pattern. A transverse section extending from normal to diseased tissue showed a progression from normal polyps to pale, swollen polyps, followed by remnant spicule-like structures, and finally fine black matter and bare substratum in the middle of the lesion. The disease occurred in one or more portions of the colony simultaneously. Disease frequency and total area infected increased significantly with colony size. Generally, the disease affected 5% of the total colony area, and occurred when gonad development was maximal. Therefore, 20.5% (n = 306), and 14.6% (n = 578) of the population was infected in two consecutive years, respectively. Disease exhibited higher rates during summer (tourist season) and fall, and decreased significantly in the winter with the presence of cool water. Factors associated with the increased instance of disease during the summer were higher temperatures, precipitation and sewage; the opposite was noted in the winter. Disease frequency varied significantly between years, seasons, sites and depths. Colonies exhibited higher disease frequency in Ponta Recife characterized by high levels of sedimentation, increased turbidity and low levels of incident light with respect to Praia Portinho. Colonies in shallow water exhibited greater frequency of disease compared to those in deeper water. Physiological stress, low energy input, energy expenditure and energy re-allocation may increase the susceptibility of P. caribaeorum colonies to disease. It is suggested that this disease may play an important role in the life history of P. caribaeorumbecause of its influence on partial mortality, colony area, population size structure, reproduction and ultimately fitness. This represents the first report of disease-related mortality in reef zoanthids of the Southwestern Atlantic.     

Predation on and by pelagic Turbellaria in some lakes in Brazil

Planktonic Turbellaria are of common occurrence in both natural and man-made lakes in Brazil. Experiments were performed in 1987 and 1989 to determine which zooplankton species are consumed by predatory Mesostoma sp. from three natural lakes in the Rio Doce Valley. Experiments were also performed in 1989 with a yet unidentified flatworm from Barra Bonita reservoir. Both predators consumed Daphnia and Ceriodaphnia at a high rate: 4 individuals per day in the case of Mesostoma sp., a large species and 1.5 ind day^–1 in the case of the smaller species from Barra Bonita reservoir. Consumption of copepod nauplii, copepodids and adults was much lower, and Ostracoda were not consumed at all. Experiments on food selectivity showed a clear preference by the flatworms for cladocerans.In the lakes studied, flatworms are heavily preyed upon by larvae of Chaoborus and by Mesocyclops species.Turbellaria densities in the natural lakes were around 300 individuals per cubic meter, whereas in Barra Bonita reservoir, 1000 individuals per cubic meter was a mean value in a fifteen days study.Federal University of São Carlos - Laboratory of LimnologyUniversity of São Paulo - Canter of Water Resource and Applied EcologyPost-graduate student - University of São Paulo     

Macroalgae of a stream in southeastern Brazil: composition,seasonal variation and relation to physical and chemical variables

Macroalgal seasonality was studied monthly in a second-order stream in the north-west of São Paulo State, S.E. Brazil. Seasonal variation was based on frequency and percentage cover. Seven species were found during the study period, three of which (Chantransia stage of Sirodotia delicatula, Homoeothrix juliana and Klebsormidium subtile) were encountered throughout the year and showed well-defined seasonal patterns as well as the highest value of frequency and percentage cover. Chantransia and H. juliana dominated in summer and fall, while for K. subtile winter was the most favourable period. The remaining species (Oscillatoria agardhii, Microcoleus subtorulosus, Oedogonium sp. and Chaetophora elegans) had no clear seasonal pattern, in addition to their low values of frequency and percentage cover. Individually, K. subtile correlated with higher number of physical and chemical variables (oxygen, pH, precipitation, temperature, daylength, conductance and turbidity) than Chantransia and H. juliana (discharge and depth). Principal component analyses revealed that no single variable was responsible for the macroalgal seasonal dynamics. The variables most closely related to seasonal variation of the macroalgal community were daylength, precipitation, discharge, turbidity and dissolved oxygen. Precipitation and flow were suggested as key factors in determining seasonality of the macroalgae.     

Distribution and abundance of arboreal species in the atlantic ombrophilous dense forest in Southeastern Brazil*

The relative densities of arboreal species of 17 surveys carried out in the Atlantic Ombrophilous Dense Forest of São Paulo state, SE Brazil, were compared by means of multivariate analysis (cluster, TWINSPAN, PCA, DCA and CCA) to assess floristic and structural variation. The arboreal flora of this vegetation formation is heterogeneous: out of the 771 specific binomials cited, 478 were recorded only once. As the results were similar whether these 478 species were included or not, they were therefore excluded from subsequent analyses. The cluster analysis and TWINSPAN recognised two floristic-structural groups: Coastal Province and Atlantic Plateau. The DCA resulted in a gradient related to distance from the sea, from the Coastal Province towards the Atlantic Plateau (₁=0.6944). The CCA confirmed this separation on the first axis (₁=0.6944; 12.7% of total variance; p<0.01) and showed this gradient to be associated with altitude and latitude on one hand and temperature and precipitation on the other. The influence of latitude and longitude was weak. Although surveys used different criteria, only the minimum individual size adopted in sampling showed a weak influence on the second axis on the CCA (₂=0.4437; 8% of total variance), and sampling method showed no influence. A positive relationship between geographical distance and floristic-structural dissimilarity was detected by the Mantel test (Z _obs=0.320; Z _ave=0.300; p<0.001). The predominance of arboreal species of restricted distribution and the great spatial variation of abundance would appear to indicate narrow niches. The occurrence of complex and non-linear gradients suggests the importance of several other abiotic features in the spatial distribution and abundance of arboreal species in the Atlantic Ombrophilous Dense Forest in the state of São Paulo.     

Sensitivity facilitation in the insect eye

Summary ERG amplitude facilitation, observed in the eye ofAtta sexdens after light adaptation, was studied as a function of duration and intensity of adaptation, of dark interval between adapting and test stimuli, and of level of steady background illumination. Results show that sensitivity facilitation in this eye cannot be regarded as a minor effect since it covers a 2 log unit range, the same as that obtained for conditions that produce sensitivity reduction. Maximum facilitation occurs with short and intense light adaptation. The time span of the effect is close to 2 min, and its maximum amplitude may be attained up to 20 s after light adaptation. Increase in background illumination gradually erases facilitation. However, the facilitated response is less sensitive to background illumination than the dark adapted response. Long durations of light adaptation cause ERG decrease, or inhibition. A comparison of these two end results of light adaptation suggests that they arise from different processes, perhaps with distinct origins.Supported by a grant from Fundação de Amparo à Pesquisa do Estado de São Paulo, to the senior author (Contract n 71/1141)With a Fellowship from Fundação de Amparo à Pesquisa do Estado de São Paulo (N 74/388)We wish to express our appreciation to Henrique Fix for his editorial assistance, and to Celia Jablonka for laboratory help.     

Mycoflora of the toxic feeds associated with equine leukoencephalomalacia (ELEM) outbreaks in Brazil

The mycoflora of 39 feed samples associated with 29 Equine Leukoencephalomalacia (ELEM) outbreaks was studied from 1988 to 1990, in Brazil. Microbiological examination indicatedFusarium spp. as the most frequent mold which occurred in 97.4% of samples followed byPenicillium spp. in 61.5% andAspergillus spp. in 35.9%. The moisture content of feed implicated in death of horses was above 15% which can favor the development ofFusarium spp. From the genus,F. moniliforme was the predominant species with an occurrence of 82.0%. Two additional species, not commonly associated with animal toxicosis, were isolated in low frequency,F. proliferatum (12.8%) andF. subglutinans (2.6%). It is important to emphasize that the isolation ofF. proliferatum andF. subglutinans from feed obtained from the epizootic areas has not been documented previously in Brazil.Part of the thesis of M.C.A. Meireles to get the degree of Doctor Leucoencefalomalácia Eqüina (LEME) no Brasil: Aspectos epizootiológicos, microbiológicos e micotoxicológicos, Preliminary communication in 1989, Congresso Brasileiro de Microbiologia, Rev Microbiol (São Paulo) 20 (Sup. 1): 359 (F 181).     

Habitat and Population Data of Troglobitic Armored Cave Catfish, Ancistrus Cryptophthalmus Reis, 1987, from Central Brazil (Siluriformes: Loricariidae)

Population ecology of the troglobitic armored catfish, A. cryptophthalmus, from caves in São Domingos karst area of central Brazil, was studied in a two-census capture-mark-recapture study carried out during the dry season of 1999. Like many loricariids, including epigean Ancistrus catfishes from that area, A. cryptophthalmus is a typical bottom-dweller with a strong preference for rocky substrates in fast-flowing stream sectors. Relatively high population densities, when compared to other cavefishes, were recorded in the studied cave sections: 0.9 individuals m^–2 in Angélica Cave and 0.5 individuals m^–2 in Passa Três Cave. Passa Três Stream is a small tributary of the São Vicente Cave system, and the estimated population for Passa Três Cave (ca. 2000 m long) is around 1000 individuals. On the other hand, the large Angélica Cave Stream (8 km long) harbors a very large population, conservatively estimated at 20 000 individuals. No fish movements of distances longer than 100 m were recorded in the 40-day period. In Passa Três Cave, a few movements of distances up to 60 m were detected. Proportion of mature females in Angélica Cave was higher than in Passa Três Cave, possibly reflecting a greater food availability in the first cave. Mean individual growth rates in Angélica Cave (1.35 mm month^–1 for size class <41 mm SL, 0.17 mm month^–1 for size class >41 mm SL) point to relatively high longevities, possibly attaining 15 years.     

A comparison,by sweep sampling,of the arthropod fauna of secondary vegetation in Michigan,England and Costa Rica

• 1 Six 800-sweep samples of English and Michigan (“old field”) secondary vegetation arthropods are compared with Costa Rican samples taken in the same way.
• 2 Parasitic Hymenoptera and spiders accounted for a larger proportion of the arthropod fauna in the mid-latitude than the tropical samples.
• 3 In one English field, the seasonal change in insect numbers was 88% of that recorded over all the seasonal and elevational changes examined in Costa Rica. Furthermore, the difference in the total dry weights of the arthropod fauna between December and July was similar to the difference found between the wet and dry seasons in tropical secondary vegetation (also similar to the difference between day and night values during the dry season).
• 4 Aphids and Psyllidae were far more abundant in the English site than in the Costa Rican mainland sites.
• 5 In mid-summer, the English field had far more arthropods in it than did any of the tropical sites sampled.

     

Hydrography and characteristics of the phytoplankton in shelf and oceanic waters off southeastern Brazil during winter (July/August 1982) and summer (February/March 1984)

The physical and chemical environment, and the phytoplankton primary production of southeastern Brazil were studied in relation to the general oceanographic structure during two research cruises (winter and summer). In each cruise, a total of 91 stations were occupied. Data were collected on the spatial distribution of nutrients, phytoplankton biomass and photosynthetic capacity over the coastal, shelf and oceanic areas off São Paulo, Paraná and Santa Catarina States.During wintertime, the mixing processes between tropical warm waters of the Brazil Current and subantarctic waters of the Malvinas Current formed strong environmental gradients. The drainings of Rio de La Plata and Lagoa dos Patos are transported northwards by coastal currents, enriching the shelf waters off Santa Catarina State with inorganic nutrients and consequently increasing the chlorophyll a to the highest concentrations (> 3.5 mg m ^–3) measured during the two cruises. In slope waters chlorophyll values were always low (0.05–0.45 mg m ^–3). The chlorophyll within the euphotic layer varied from 8.8–36.7 and 1.2–18.5 mg m^–2 during winter and summer, respectively.The surface photosynthetic rates during winter and summer cruises ranged respectively from 0.21–9.17 and 0.66–19.60 mgC/mgChl.a/h. The mean rates were higher in nearshore waters and decreased seaward.The thermal structure of the water column affected the vertical distribution of chlorophyll a and photosynthesis within the euphotic zone; During unstratified periods (winter) they were uniformly distributed but the occurrence of subsurface peaks of chlorophyll and strong photosynthetic inhibition of low light adapted cells in deeper layers are associated to the seasonal thermocline. Occasionally, upwelling of deep waters from shelf break enriched the deeper euphotic layers in offshore areas. Intensive upwelling was observed off Paranagua Bay (Parana State) and the mechanisms of its formation are discussed.     

Phylogenetic analysis of Theobroma (Sterculiaceae) based on Kunitz-like trypsin inhibitor sequences

Trypsin inhibitor gene sequences were used to investigate the phylogenetic relationships among Theobroma and Herrania species, considered as sister-groups, with particular interest on the monophyly and infra-generic relationships of Theobroma. The presumed amino acid sequences of 23 analyzed samples, from 11 Theobroma and three Herrania species, comprising all sections from both genera, demonstrated a high similarity with a previously characterized T. cacao Kunitz trypsin inhibitor. The trypsin inhibitor gene accumulated mutations at faster rate than prior analyzed nuclear or chloroplastic genes. None of the sequences presented introns. The phylogeny of the trypsin inhibitor sequences was congruent with the phylogenetic hypotheses of the Theobroma and Herrania species based on morphology. The monophyly of Theobroma was not strongly supported, corroborating previously described absence of obvious synapomorphies for Theobroma. The species grouped consistently according to genus and section. The monophyly of all Theobroma sections was supported, except for section Glossopetalum, which was paraphyletic to section Andropetalum. Evidences sustain that T. mammosum may be included into section Glossopetalum. The potential use of trypsin inhibitor gene sequences in phylogenetic studies of Theobroma was demonstrated.We acknowledge the financial support by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); International Foundation of Science (IFS), and the permission from Empresa Brasileira de Pesquisas Agropecuária (EMBRAPA); Comissão Executiva do Plano da Lavoura Cacaueira (CEPLAC) to use the plant material. We thank the useful comments from the reviewers.     

Species composition and seasonal abundance of zooplankton in two Ethiopian Rift Valley lakes — Lakes Abiata and Langano

The composition and annual cycle of the zooplankton of two Ethiopian Rift Valley soda lakes is described. Lake Langano has a conductivity of 1 400 to 1800 µS cm^–1 and a permanent mineral turbidity. Lake Abiata is more concentrated (conductivity 19 000 to 23 000 µS cm^–1) and more alkaline but less turbid; it is characterised by dense phytoplankton blooms, mainly cyanophytes.The zooplankton assemblage is typically tropical, with relatively few species of Cladocera and Copepoda. There was a marked difference in zooplankton between the two lakes, Lake Abiata showing much higher concentrations and greater wet season/ dry season differences. The species composition was also different. Lake Abiata lacked Cladocera, and calanoid copepods occurred only during the wet season with lower conductivities. These two phenomena were attributed to high sodium bicarbonate concentration and to dense cyanophyte blooms. Eleven species of rotifers occurred in Lake Abiata, including six Brachionus spp. but B. rubens was the only rotifer found in Lake Langano. The seasonal variation of the zooplankton is discussed in relation to seasonal fluctuations in conductivity and Chl a concentration.     

Temporal variability and production of Euterpina acutifrons (Copepoda: Harpacticoida) in the Cananéia Lagoon estuarine system,São Paulo,Brazil

Diel and seasonal variations in abundance, population structure, biomass and production rate of the harpacticoid copepod Euterpina acutifrons were studied in the Cananéia Lagoon estuarine system, São Paulo, Brazil. Zooplankton samples were collected at 4-h intervals during multiple 24-h periods, from February 1995 to January 1996. Copepodites and adults of E. acutifrons were present in the plankton throughout the year (temperature, 18.6–29.4 °C; salinity, 4.5–33.0 psu; chlorophyll-a concentration, 1.32–20.42 g l^–1). Abundance of E. acutifrons showed considerable diel variations. On most sampling dates, higher abundances were recorded at times when salinity was higher. Biomass varied from 0.044 ± 0.046 (daily mean ± SD) to 5.264±3.425 mg C m^–3. The estimated production rates (minimum ± SD–maximum ± SD) were 0.034±0.035–4.95±3.25 (Ikeda-Motoda model), 0.035±0.036–5.123±3.347 (Huntley-Lopez model), and 0.016±0.017–2.101±1.372 mg C m^–3 d^–1 (Hirst-Sheader model).     

The biodiversity and conservation of the birds of São Tomé and Príncipe

At present the majority of the endemic bird species occurring on São Tomé and Príncipe remain common, the rarer species being those largely confined to primary rainforest. In 1990 the dwarf olive ibis (Bostrychia bocagei), São Tomé fiscal shrike (Lanius newtoni), São Tomé short-tail (Amaurocichla bocagii) were rediscovered and in 1991 the São Tomé grosbeak (Neospiza concolor) was seen for the first time since 1888. Lowland primary forest is the only habitat on São Tomé in which all the endemic species are found. Primary forest on Príncipe remains largely unsurveyed since the beginning of the century. Due to the decline in the cocoa industry and poor infra-structure post-independence the extent of secondary forest is probably at its greatest since the late 1800s. This habitat is an important buffer zone against development for the remaining primary forest and also contains important populations of many of the endemic species, in particular the São Tomé scops owl (Otus hartlaubi), São Tomé oriole (Oriolus crassirostris) and giant weaver (Ploceus grandis). On both islands the remaining areas of primary forest need immediate protection and suitable boundaries have been designated under the Zona Ecológica plan. Fortunately, except for an important area around Lagôa Amélia, primary forest is not under immediate threat, although a variety of pressures are likely to increase. In conjunction with the protection of primary forest, a plant for managing the remaining timber resource on the islands will be a vital requirement, particularly if areas of shade forest, an important habitat for endemic bird species and a potentially valuable economic resource, are to be conserved and sustainably managed.     

Observations on Savanna vegetation-types in the Guianas

Summary The vegetation was studied of a number of savannas in northern and southern Surinam, and in French Guiana. The results are compared in particular with the vegetation classification proposed earlier for northern Surinam, and with some records from the northern Rupununi Savanna, Guyana (Van Donselaar 1965).The savannas studied near Brownsweg (northern Surinam) have vegetation types that correspond completely with those of some other savannas of the same geological-pedological type more to the North, as described before. New is the finding of a type of scrub bordering the savanna, being the scrub equivalent of a type of bushes described earlier as theMarlierea type.On the top and the slopes of the Blauwe Berg near Berg en Dal (northern Surinam) an anthropogenic savanna has developed. Two new vegetation types are recorded here that belong to the alliance Rhynchosporo-Trachypogonion. At the foot of the hill a flat savanna supports a vegetation that gives the impression of being of recent origin and unbalanced.It appears possible to apply the existing classification to the communities found on savannas near Cayenne (French Guiana). In this area the conspicuousByrsonima verbascifolia (var.villosa fo.spathulata) occurs in several undescribed vegetation types that belong to various entities. A xerophilous and a hygrophilous community ofByrsonima verbascifolia are distinguished, belonging to the Rhynchosporo-Trachypogonion and the Bulbostylidion lanatae, respectively.On the Sipaliwini Savanna in southern Surinam most vegetation types do not fit into one of the existing alliances. However, if new alliances would be described, it should be possible to include them into the existing orders. There probably is an alliance, called here communities ofTrachypogon plumosus andBulbostylis spadicea, that might be regarded as the southern counterpart of the Rhynchosporo-Trachypogonion in the order Trachypogonetalia plumosi, and a supposed alliance with muchRhynchospora graminea andR. globosa might have the same position with regard to the Imperato-Mesosetion in the order Paspaletalia pulchelli. Among the communities that might be included in the alliance Axonopodion chrysitidis there is one occurring on sandy soil without a hog-wallow structure at the surface. Floristically it has connections with the Paspaletalia pulchelli but it also has many characteristic species of its own. Whether this community has to be placed in a distinct alliance will have to depend on the results of further investigations in this area. Anyhow, more data are needed for the drafting of a complete picture of the rich and interesting Sipaliwini Savanna.On a savanna south-west of the airstrip Sipaliwini (southern Surinam) the vegetation consists mainly of communities belonging to the Bulbostylidion lanatae.Summarizing the above-mentioned results, one may say that a number of communities not studied before are added to the picture of the savanna vegetation of the Guianas. It proved possible to integrate these communities without much difficulty in the classification presented earlier that so far has functioned as a practical framework.

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Beobachtungen an Savannen vegetationstypen in den Guayanas

Zusammenfassung Die Vegetation einiger Savannen in Nordsurinam, Südsurinam und Französisch-Guayana wurde untersucht. Die Ergebnisse werden besonders verglichen mit einer schon früher vorgeschlagenen Vegetationsklassifikation und mit einigen Aufnahmen der nördlichen Rupununisavanne in Guayana, dem ehemahligen Britisch-Guayana (Van Donselaar 1965).Die bei Brownsweg (Nordsurinam) untersuchten Savannen haben Vegetationstypen, die denjenigen anderer, schon früher bearbeiteter, mehr nördlich gelegener Savannen desselben geologisch-pädologischen Typs ganz ähnlich sind. Es wurde ein neuer, die offenen Savannen begrenzender Typ von Gestrüpp gefunden. Er ist als Gestrüppäquivalent eines Buschtyps, der früher alsMarlierea-typ beschrieben worden ist, zu betrachten.Auf dem Gipfel und den Hängen des Blauen Berges bei Berg en Dal (Nordsurinam) hat sich eine anthropogene Savanne entwickelt. Zwei neue Vegetationstypen wurden hier angetroffen, beide dem Verband Rhynchosporo-Trachypogonion angehörend. Eine flache Savanne am Fuß des Berges trägt eine Vegetation, die rezent entstanden und noch nicht ausgeglichen zu sein scheint.Es ergibt sich, daß die vorhandene Klassifikation auch auf die Pflanzengesellschaften einiger Savannen bei Cayenne (Französisch-Guayana) zutrifft. In dieser Gegend findet sich die auffälligeByrsonima verbascifolia (var.villosa fo.spathulata) in mehreren unbeschriebenen Vegetationstypen, die verschiedenen Einheiten angehören. Es wurde eine xerophile und eine hygrophile Gesellschaft vonByrsonima verbascifolia unterschieden, die den Verbänden Rhynchospora-Trachypogonion bezw. Bulbostylidion lanatae zugeteilt werden können.Die meisten Vegetationstypen der Sipaliwinisavanne (Südsurinam) passen nicht in einen der beschriebenen Verbände. Wenn aber neue Verbände dafür beschrieben würden, so könnten diese in den bestehenden Ordnungen untergebracht werden. Es ist wohl ein Verband zu unterscheiden, hier Gesellschaften vonTrachypogon plumosus undBulbostylis spadicea genannt, der als ein südliches Gegenstück des nördlichen Rhynchosporo-Trachypogonion-Verbandes in der Ordnung Trachypogonetalia plumosi zu betrachten wäre, und vermutlich steht ein Verband mit vielRhynchospora graminea undR. globosa in demselben Verhältnis zum Imperato-Mesosetion-Verband in der Ordnung Paspaletalia pulchelli. Unter den Gesellschaften, die dem Verband Axonopodion chrysitidis zuzurechnen sind, gibt es eine auf sandigem Boden ohne Hügel-und-Schlenken-Struktur. Sie hat floristische Beziehungen zu den Paspaletalia pulchelli, aber hat auch manche eigene Kennarten. Die Entscheidung, ob diese Gesellschaft in einem neuen Verband unterzubringen ist, muß von weiteren Untersuchungsergebnissen abhängig gemacht werden. Überhaupt ist noch viel weitere Arbeit erforderlich, bevor das Bild der Vegetation der reichen und interessanten Sipaliwinisavanne vollständig ist.Die Vegetation einer Savanne südwestlich des Flugplatzes Sipaliwini (Südsurinam) besteht hauptsächlich aus Gesellschaften des Verbandes Bulbostylidion lanatae.Als Zusammenfassung der obenerwähnten Ergebnisse kann man sagen, daß eine Anzahl von bisher nicht bekannten Gesellschaften dem Gesammtbild der Savannenvegetation der Guayanas hinzugefügt worden ist. Es hat sich gezeigt, daß diese Gesellschaften ohne viel Mühe in die früher veröffentlichte Klassifikation eingefügt werden können, so daß diese als ein praktisches Ramenwerk brauchbar bleibt.

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Observaçoes sôbre vegetaçoes de savana nas Guianas

Resumo A vegetação foi estudada em várias savanas ao norte e sul de Suriname, e na Guiana Francêsa. Os resultados foram comparados, em particular, com a classificação de tipos de vegetação obtida antes no norte de Suriname e com alguns dados da parte norte da Savana Rupununi, Guiana Inglesa, agora Guyana (Van Donselaar 1965).As savanas estudadas perto de Brownsweg (norte do Suriname) possuem tipos de vegetação que correspondem completamente com aqueles de outras savanas do mesmo tipo geológico-pedológico mais ao norte, já descritos antes. Foi encontrada aí uma faixa arbustiva bordejando a savana que é nova e, equivalente ao tipo de capões descrito anteriormente como o tipo deMalierea.No topo e nas vertentes do Blauwe Berg perto de Berg en Dal (norte do Suriname) uma savana antropogênica encontra-se desenvolvida aí. Dois tipos novos de vegetação são aí apontados que pertencem a aliança Rhynchosporo-Trachypogonion. No sopé de colina encontra-se uma savana plana que apresenta uma vegetação dando a impressão se sêr de origem recente e em desequilíbrio.Parece sêr possível aplicar a classificação existente das comunidades encontradas nas savanas próximas à Cayenne (Guiana Francêsa). Nessa área a conspícuaByrsonima verbascifolia (var.villosa fo.spathulata) ocorre em vários tipos vegetais não descritos que pertencem a entidades diversas. Uma comunidade xerófila e uma higrófila deByrsonima verbascifolia são definidas, pertencendo a primeira ao Rhynchosporo-Trachypogonione, a segunda ao Bulbostylidon lanatae.Na Savana Sipaliwini ao sul de Suriname a maioria dos tipos de vegetação não se acomodam a nenhuma das alianças existentes. Entretanto, se novas alianças fossem criadas, seria possível incluilas nas ordens existentes. É provàvelmente uma aliança chamada aquí comunidades deTrachypogon plumosus eBulbostylis spadicea que pudesse sêr considerada como correspondente sulino do Rhynchosporo-Trachypogonion na ordem Trachypogonetalia plumosi, e uma aliança com muitaRhynchospora graminea eR. globosa que pudesse estar na mesma situação em relação ao Imperato-Mesosetion da ordem Paspaletalia pulchelli. Entre as comunidades possíveis de sêr incluidas na aliança Axonopodion chrysitidis, é uma que se encontra em solo arenoso, mas sem a superfície com caneluras reticuladas que é chamada hogwallowed em inglês e kaw-foetoe no Suriname. Além das conecções florísticas com a Paspaletalia pulchelli tem muitas espécies características próprias. Se esta comunidade tem que sêr localizada numa aliança separada, dependerá dos resultados de investigações futuras nesta área. Em tôdo caso mais dados são necessários para a delineação dum desenho completo da rica e interessante Savana Sipaliwini.Na savana SW do compo d'aterrisagem Sipaliwini (sul do Suriname) a vegetação consiste, a maioria, de comunidades de Bulbostylidion lanatae.Reunindo os resultados acima mencionados, podemos dizer que um número de comunidades não estudados antes são acrescentados à pintura da vegetação das savanas das Guianas. Também evidenciou-se sêr possível integrar estas comunidades sem muitas dificuldades não classificação apresentada antes, que até agora funciona como moldura prática.

     

Improved culture media for growth of Bradyrhizobium japonicum

A freshly-prepared yeast extract at 30 or 50 g/l improved the growth of Bradyrhizobium japonicum SEMIA 587 in a 5-l stirred fermenter. Monosodium glutamate or a commercial yeast extract at 2.0 g/l almost doubled cell mass productivity and cell viability when added at the end of the first exponential growth phase.The authors are with the Divisão de Quimica, Agrupamento de Biotecnologia, Instituto de Pesquisas Tecnológicas do Estado de São Paulo, S/A.-IPT-Cidade Universitária s/n., Caixa Postal 7141, CEP 01064-970, São Paulo, SP, Brazil     

Disseminated dermatophytosis caused by Microsporum gypseum in two patients with the acquired immunodeficiency syndrome

Microsporum gypseum is not a common agent of human dermatophytosis. To the best of our knowledge, this fungus has not been described in human immunodeficiency virus (HIV)-infected patients. We report a tinea corporis infection with atypical presentation caused by M. gypseum in two patients with the acquired immunodeficiency syndrome (AIDS) studied at the São Paulo Hospital (São Paulo, Brazil).This revised version was published online in October 2005 with corrections to the Cover Date.