Seasonal variation of biomass and productivity of the periphytic community on artificial substrata in the Jurumirim Reservoir (São Paulo, Brazil)

The seasonal variation of the periphytic community attached to an artificial substratum (glass tubes) was studied during two different periods in a lagoon connected to the Paranapanema River, the main tributary of the Jurumirim Reservoir (São Paulo-Brazil). An analysis of dry weight, ash free dry weight, chlorophyll a, phaeophytin and primary productivity of periphyton was carried out. The first experiment lasted from August to December 1993, the second from February to June 1994. Tubes were removed after 7, 14, 21, 28, 60, 90 and 119 days of incubation. In the 1st experiment, the periphytic community reached a higher biomass after the 4th week of colonization (28th day), in the 2nd experiment after the 2nd week (14th day). This discrepancy is related to seasonal differences in environmental factors (water temperature, nutrients concentrations and water discharge) that determine initial colonization. After the first stages of colonization, the biomass and primary productivity of periphyton reached their maximum values after the 60th day of incubation. In both experiments, three developmental phases could be discerned. In the initial phase, an exponential growth was observed. In the second phase, the bioderm reached its maximum biomass and productivity. In the third phase, a decrease of biomass and productivity occurred.

Effect of substrata on the development of stem cuttings of Lippia alba (Mill.) NEBR. - Limonene-carvone chemotype

Studies were conducted to show the effect of different substrata on the development of stem cuttings of Lippia alba made of limonene-carvone chemotype. The experiment was done in the College of Agronomical Sciences, UNESP, Botucatu, SP, Brazil in 2000. The cuttings were planted in polystyrene trays consisting of 72 cells. The cuttings had about 0.20 m of length and were put in the following substrata:Fine sand (T1), commercial substratum (T2), carbonised rice peel and local soil (T3), local soil, cow manure and carbonised rice peel (T4), vermiculite (T5), and carbonised rice peel (T6). After 40 days the development of stem cuttings were evaluated. High rate of rooting of stem cuttings was verified, with average of 95 10 and no significant difference between the treatments. In relation to dry mass of aerial parts and dry mass of roots, significant differences were found. For dry mass production of aerial parts the commercial substratum (T2) and the local soil, cow manure, carbonised rice peel (T4) were optimal. For mass of roots the local soil, cow manure, carbonised rice peel (T4) proved to be the best.

Effect of substrata on the development of stem cuttings of Lippia alba (Mill.) N. E. BR. - Limonene-carvone chemotype

Studies were conducted to show the effect of different substrata on the development of stem cuttings of Lippia alba made of limonene-carvone chemotype. The experiment was done in the College of Agronomical Sciences, UNESP, Botucatu, SP, Brazil in 2000. The cuttings were planted in polystyrene trays consisting of 72 cells. The cuttings had about 0.20 m of length and were put in the following substrata: Fine sand (T1), commercial substratum (T2), carbonised rice peel and local soil (T3), local soil, cow manure and carbonised rice peel (T4), vermiculite (T5), and carbonised rice peel (T6). After 40 days the development of stem cuttings were evaluated. High rate of rooting of stem cuttings was verified, with average of 95% and no significant difference between the treatments. In relation to dry mass of aerial parts and dry mass of roots, significant differences were found. For dry mass production of aerial parts the commercial substratum (T2) and the local soil, cow manure, carbonised rice peel (T4) were optimal. For mass of roots the local soil, cow manure, carbonised rice peel (T4) proved to be the best.

Diversity of decapod crustaceans at the interface of unconsolidated seabed areas and rocky shores in tropical/subtropical Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morfologia e avaliação do crescimento inicial de plântulas de Bactris gasipaes Kunth. (arecaceae) em diferentes substratos

Este trabalho teve por objetivos descrever a morfologia dos diásporos, as fases da germinação e determinar o substrato mais adequado para o crescimento inicial de plântulas de pupunha. Periodicamente, unidades representativas de cada fase de germinação foram retiradas para a descrição da seqüência dos eventos morfológicos. Os substratos usados para o crescimento inicial foram Plantmax HT, areia, terra (latossolo roxo) e outro com proporções iguais de terra, areia e esterco (TAE). Avaliou-se o crescimento inicial das plântulas aos 101 dias após o transplante, com base na sua altura, número de folhas, comprimento e largura das folhas. Observou-se que as sementes são albuminosas, com endosperma oleaginoso e de consistência relativamente dura. O embrião é lateral, periférico e relativamente indiferenciado, de forma cônica. A germinação inicia-se com o desenvolvimento de uma massa de células indiferenciadas na depressão micropilar. Posteriormente, esta massa de células torna-se cilíndrica, com a diferenciação dos primórdios caulinar e radicular. O primórdio caulinar é constituído por três bainhas envolvendo a primeira folha. Estas se abrem sucessivamente, permitindo a emergência da folha primária. Entre os substratos testados, de acordo com os parâmetros avaliados, os mais adequados para crescimento inicial de mudas de Bactris gasipaes Kunth foram o TAE e o Plantmax.

Efeitos de substratos e temperaturas na germinação de sementes de tamareira-anã (Phoenix roebelenii O'Brien)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Biodigestão anaeróbia dos dejetos de cabritos Saanen alimentados com dietas com diferentes proporções volumoso e concentrado

Avaliaram-se os efeitos da idade do animal e da proporção de volumoso nas dietas sobre a biodigestão anaeróbia dos dejetos de cabritos Saanen. Foram utilizadas as fezes produzidas por cabritos Saanen aos 90, 120 e 150 dias de idade e alimentados com dietas de três relações volumoso:concentrado (80:20, 60:40 e 40:60), representando as dietas 1, 2 e 3, respectivamente. Utilizaram-se biodigestores tipo batelada de bancada com capacidade para 12 litros de substrato em fermentação e 8% de sólidos totais iniciais para determinação das produções e dos potenciais de produção de biogás e metano, da redução de sólidos voláteis e quantificação dos teores de minerais no afluente e efluente. As maiores reduções de sólidos voláteis foram observadas nos substratos preparados com as fezes de cabritos aos 150 dias alimentados com a dieta com relação volumoso:concentrado de 40:60. Os melhores rendimentos de substrato ou fezes foram obtidos com os dejetos dos cabritos de 120 e 150 dias de idade alimentados com a dieta com relação volumoso:concentrado 40:60. As maiores concentrações de minerais nos biodigestores foram observadas para as fezes de cabritos de 150 dias de idade alimentados com a dieta com relação volumoso:concentrado 40:60. A biodigestão anaeróbia é eficiente na remoção de coliformes nos dejetos de caprinos, proporcionando efluentes com no máximo 4,3 × 10² coliformes totais termotolerantes por grama de material.

Formação de mudas de eucalipto com utilização de lixo orgânico e níveis de irrigação calculados por dois métodos

O estudo das características e das possibilidades de utilização de Resíduo Sólido Urbano (R.S.U.) e mais especificamente de Resíduo Sólido Orgânico Urbano (R.S.O.U.), no Brasil e no Mundo, ainda não produziu informações que possibilitem conhecimentos suficientes para tomadas de decisões que estão sendo exigidas, em razão do crescente volume de resíduos produzidos e os impactos ao meio ambiente. Este trabalho teve o objetivo de estudar o efeito da irrigação associada ao uso de R.S.O.U. para formação de mudas de eucalipto. A pesquisa foi desenvolvida na UNESP, Câmpus de Jaboticabal - SP, sendo adotado como delineamento estatístico o esquema fatorial inteiramente casualizado. Foram utilizados 11 substratos: dois tipos de solos (um Latossolo Vermelho eutrófico e um Latossolo Vermelho distrófico), com e sem adubação química, seis misturas de solo e R.S.O.U., e um utilizando somente R.S.O.U. Sementes de eucalipto var. Citriodora Hooker foram semeadas diretamente em topetes e irrigadas com base em dois métodos de quantificação da água evapotranspirada (tanque Classe A e determinação da massa), em quatro níveis (50; 70; 100 e 130% da evapotranspiração). Os dados coletados e analisados estatisticamente demonstraram que doses acima de 20% de R.S.O.U. na mistura, em solos destinados à produção de mudas de eucalipto, causam efeitos negativos na sobrevivência das plantas.

Gamasida (Arachnida: Acari) Edáficos de Piracicaba, Estado de São Paulo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Propagação vegetativa da alfavaca-cravo utilizando diferentes tipos de estacas e substratos

A propagação vegetativa é considerada importante ferramenta para o melhoramento de espécies lenhosas e herbáceas e vem sendo amplamente utilizada, visando melhorar e manter variedades de importância econômica e medicinal. Neste contexto utilizou-se estacas de alfavaca-cravo de 15 cm para apicais e 25 cm para as medianas, sendo estas com e sem folhas. As estacas foram plantadas em bandejas de isopor de 72 células, utilizando-se 10 substratos. Após 35 dias, as estacas foram retiradas com cuidado, sendo as partes aéreas e radiculares separadas e acondicionadas em saco de papel e mantidas em estufa a 70ºC por 48 h para posterior avaliação da matéria seca. Analisou-se a percentagem de enraizamento, número de folhas na estaca, peso de matéria seca de folha e de raiz. Não houve interação significativa entre os diferentes tipos de substrato e estaca para percentagem de enraizamento, sendo que os substratos de modo geral diferiram pouco entre si. Entre os tipos de estaca destacaram-se para esta variável a mediana sem folha e a apical com folha. Para as demais variáveis houve interação significativa entre o tipo de estaca e o substrato. A melhor estaca foi a mediana sem folhas plantadas em substrato arisco + esterco + húmus e vermiculita nas seguintes proporções: 20%:40%:40%; 40%:20%:40% e 40%:40%.

Effects of irradiance and spectral composition on the establishment of macroalgae in streams in southern Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Clues to the presence of pathogenic fungi in certain environments

The presence of various pathogenic fungi in rather unsuspected hosts and environments has always attracted the attention of the scientific community. Reports on the putative role of animals in fungal infections of humans bear important consequences on public health as well as on the understanding of fungal ecology. Fungi are ubiquitous in nature and their great capacity for adaptation allows them to survive and indeed, to thrive, in plants, trees and other natural substrata. Nonetheless, we are just beginning to learn the significance that these diverse fungal habitats have on the increasing number of immunosuppressed individuals. The accidental or permanent presence of fungi in animals, plants, soils and watercourses should not be taken too lightly because they constitute the source where potential pathogens will be contracted. If those fungal habitats that carry the largest risks of exposure could be defined, if seasonal variations in the production of infectious propagules could be determined, and if their mode of transmission were to be assessed, it would be possible to develop protective measures in order to avoid human infection. Additionally, unsuspected avenues for the exploration of fungal survival strategies would be opened, thus enhancing our capacity to react properly to their advancing limits. This paper explores several ecological connections between human pathogenic fungi and certain animals, trees, waterways and degraded organic materials. The occurrence of such connections in highly endemic areas will hopefully furnish more precise clues to fungal habitats and allow the design of control programs aimed at avoiding human infection.

Choosing between Cox proportional hazards and logistic models for interval-censored data via bootstrap

This work develops a new methodology in order to discriminate models for interval-censored data based on bootstrap residual simulation by observing the deviance difference from one model in relation to another, according to Hinde (1992). Generally, this sort of data can generate a large number of tied observations and, in this case, survival time can be regarded as discrete. Therefore, the Cox proportional hazards model for grouped data (Prentice & Gloeckler, 1978) and the logistic model (Lawless, 1982) can befitted by means of generalized linear models. Whitehead (1989) considered censoring to be an indicative variable with a binomial distribution and fitted the Cox proportional hazards model using complementary log-log as a link function. In addition, a logistic model can be fitted using logit as a link function. The proposed methodology arises as an alternative to the score tests developed by Colosimo et al. (2000), where such models can be obtained for discrete binary data as particular cases from the Aranda-Ordaz distribution asymmetric family. These tests are thus developed with a basis on link functions to generate such a fit. The example that motivates this study was the dataset from an experiment carried out on a flax cultivar planted on four substrata susceptible to the pathogen Fusarium oxysoprum. The response variable, which is the time until blighting, was observed in intervals during 52 days. The results were compared with the model fit and the AIC values.

Stirring, charging, and picking: hunting tactics of potamotrygonid rays in the upper Paraná River

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of culture conditions on the biomass determination by ergosterol of Lentinus crinitus and Psilocybe castanella

Estimating fungal growth is important in processes of soil bioremediation. It has been demonstrated that ergosterol is a good indicator of fungal biomass in solid substrata. In the present study were evaluated the effects upon the ergosterol rate of Lentinus crinitus Berk. and Psilocybe castanella Peck through the culture conditions of these fungi, which are evaluated for the bioremediation of soils contaminated by organochlorates. A good correlation between fungal biomass and ergosterol was observed for both species. The culture conditions did not influence the ergosterol rate of L. crinitus. Yet the ergosterol rate of P. castanella was influenced from 35 days of culture and when grown in the presence of 15.00 g hexachlorobenzene l(-1) of culture medium. So it is possible to estimate growth of both species using ergosterol as indicator in processes of soil bioremediation since the influences observed in the ergosterol rate of P. castanella are considered.