Spatial and temporal variation in population structure of Hemigrammus marginatus (Characiformes: Characidae) in streams of the Ivinhema River Basin, Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Spatial and temporal variability in soil CO2-C emissions and relation to soil temperature at King George Island, maritime Antarctica

Few studies have examined the effects of temperature on spatial and temporal trends in soil CO2-C emissions in Antarctica. In this work, we present in situ measurements of CO2-C emissions and assess their relation with soil temperature, using dynamic chambers. We found an exponential relation between CO2 emissions and soil temperature, with the value of Q10 being close to 2.1. Mean emission rates were as low as 0.026 and 0.072 g of CO2-C m-2 h-1 for bare soil and soil covered with moss, respectively, and as high as 0.162 g of CO2-C m-2 h-1 for soil covered with grass, Deschampsia antarctica Desv. (Poaceae). A spatial variability analysis conducted using a 60-point grid, for an area with mosses (Sannionia uncianata) and D. antarctica, yielded a spherical semivariogram model for CO2-C emissions with a range of 1 m. The results suggest that soil temperature is a controlling factor on temporal variations in soil CO2-C emissions, although spatial variations appear to be more strongly related to the distribution of vegetation types. © 2010 Elsevier B.V. and NIPR.

Spatial variability structure of soil CO2 emission and soil attributes in a sugarcane area

Soil CO2 emission (F-CO2) is influenced by chemical, physical and biological factors that affect the production of CO2 in the soil and its transport to the atmosphere. F-CO2 varies in time and space depending on environmental conditions, including the management of the agricultural area. The aim of this study was to investigate the spatial variability structure of F-CO2 and soil attributes in a mechanically harvested sugarcane area (green harvest) using fractal dimension (D-F) derived from isotropic variograms at different scales (fractograms). F-CO2 showed an overall average of 1.51 mu mol CO2 m(-2) s(-1) and correlated significantly (P < 0.05) with soil physical attributes, such as soil bulk density, air-filled pore space, macroporosity and microporosity. Topologically significant DF values were obtained from the characterization of F-CO2 at medium and large scales (above 20 m), with values of 2.92 and 2.90, respectively. The variations in D-F with scales indicate that the spatial variability structure of F-CO2 was similar to that observed for soil temperature and total pore volume and was the inverse of that observed for other soil attributes, such as soil moisture, soil bulk density, microporosity, air-filled pore space, silt and clay content, pH, available phosphorus and the sum of bases. Thus, the spatial variability structure of F-CO2 presented a significant relationship with the spatial variability structure for most soil attributes, indicating the possibility of using fractograms as a tool to better describe the spatial dependence of variables along the scale. (C) 2014 Elsevier B.V. All rights reserved.

LONG-TERM PATTERNS OF SPATIAL AND TEMPORAL DISTRIBUTION IN THE SEABOB SHRIMP XIPHOPENAEUS KROYERI (DECAPODA: PENAEIDAE) POPULATION IN SOUTHEASTERN BRAZIL

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Spatial-temporal variation of parasites in Cnemidophorus ocellifer (Teiidae) and Tropidurus hispidus and Tropidurus semitaeniatus (Tropiduridae) from Caatinga areas in northeastern Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

On the spatial and temporal dependence of CO2 emission on soil properties in sugarcane (Saccharum spp.) production

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Development of technologies and methods for monitoring the spatial variability of air temperature in greenhouse environment

Climatic factors directly influence growth and productivity of plants inside greenhouses, where temperature can be considered one of the major parameter in this context. Thus, the aim of this research was to develop a low cost device for thermal sensing and data acquisition, and use it in data collection and analysis of spatial variability of temperature inside a greenhouse with tropical climate. The developed equipment for thermal measurements showed a high degree of accuracy and fast responses in measurements, proving its efficiency. The data analysis interpretations were made from the elaborations of variograms and of tridimensional maps generated by a geostatistical software. The processed data analysis presented that a greenhouse without thermal control has spatial variations of air temperature, both in the sampled horizontals layers as in the three analyzed vertical columns, presenting variations of up to 3.6 ºC in certain times.

Ecological distribution of the shrimp Nematopalaemon schmitti (Crustacea: Decapoda: Caridea) in three bays on the south-eastern coast of Brazil

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

Spatial choice is biased by chemical cues from conspecifics in the speckeled worm eel Myrophis punctatus

A enguia mirongo-mirim Myrophis punctatus vive em agrupamentos de alta densidade populacional e comumente se enterra ou permanece sob o substrato. Esses comportamentos podem levar a marcas químicas no subtrato e podem, portanto, modular o uso do espaço nessa espécie. Neste estudo, testamos a hipótese de que a preferência espacial da enguia mirongo-mirim é influenciada pela presença de odor do animal coespecífico no subtrato. Mostramos que as enguias evitam a área que contém tal odor, indicando que as decisões de ocupação espacial podem ser influenciadas por pistas químicas de coespecíficos. As enguias claramente detectaram o odor de um animal coespecífico e essa percepção poderia ser um indicativo da presença de um coespecífico enterrado no substrato. Visto que elas evitam uma área contendo tal odor, sugerimos que isso poderia ser uma resposta para evitar invadir o território de um animal residente.

Mineralogy of the clay fraction of Alfisols in two slope curvatures: III - spatial variability

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

A new method to quantify macroalgae and a practical sampler for experimentation in lotic habitats

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of fluid volume variations on the calculated value of the left ventricular mass measured by echocardiogram in patients submitted to hemodialysis

The left ventricular mass (LVM) measurement is of major importance for renal patients, as ventricular hypertrophy is an important prognostic index. The echo-cardiogram of the ventricular mass is larger before than it is after hemodialysis, which can confuse data interpretation. The aim of this work is to study the influence of alterations in fluid volume on the variations in measurements of ventricular mass observed during the course of a hemodialysis. Sixteen patients with chronic renal insufficiency in hemodialysis were evaluated at the Dialysis Unit of the University Hospital-UNESP, Botucatu, São Paulo State. The left ventricular mass was calculated from echocardiograms taken before and after hemodialysis and simultaneous ultra-filtration (12 patients: UF GROUP) and before and after hemodialysis isovolemic phase with sequential ultra-filtration (10 patients: ISO GROUP). Six of these patients were submitted to measurements of left ventricular mass before and after hemodialysis in both isovolemic and simultaneous ultra-filtration procedures. In the UF group, there was significant reduction in the following parameters before and after dialysis: diastolic diameter from 54.0 +/- 6.0 mm to 45.6 +/- 7.6 mm; left ventricular mass from 342 +/- 114 g to 265 +/- 117 g; and its respective index (IMVE) from 214 +/- 68 g/m(2) to 168 +/- 71 g/m(2). The ISO group showed no statistically significant variation. The behavior of the variables of six patients submitted to both observations confirm these results. In conclusion, the variations in echocardiogram measurements of the left ventricular mass relating to hemodialysis appear to be induced by alterations of the volemic condition.

Controlling factors of benthic macroinvertebrates distribution in a small tropical pond, lateral to the Paranapanema River (São Paulo, Brazil).

The aim of the present study was to examine the benthic fauna in a marginal pond lateral to the Paranapanema River and to identify the main controlling factors of its distribution. Considering the small size of the lacustrine ecosystem, we expected that seasonal variations of the benthic community attributes are more important than spatial variations; Methods: Two samplings, one in March and another in August, were carried out at nine sites in the pond. Sediment samples were obtained through a Van Veen grab for invertebrate sorting, granulometric analysis, and for quantification of organic matter in sediment. Other abiotic factors were measured, such as water transparency, dissolved oxygen, pH, electric conductivity, temperature, and depth of sediment sampling sites. Regarding the comparative analysis at spatial scale, no significant variations in density of the benthic invertebrate community were found. Results: In relation to the studied abiotic factors, only depth presented significant differences among sampling sites; All the measured environmental parameters presented significant differences among sampling months, except depth and the physical and chemical characteristics of the sediment. The abundance of Chaoboridae and Chironomidae was the unique attribute with a significant difference in comparing the two months. A higher abundance of taxa occurred in August, especially for Oligochaeta, Nematoda, Chaoboridae, and Chironomidae; Conclusions: Because of the low structural complexity of the studied pond, we concluded that the changes in benthic macroinvertebrate community attributes were mainly due to seasonal effects.

Genomic organization and comparative chromosome mapping of the U1 snRNA gene in cichlid fish, with an emphasis in Oreochromis niloticus

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

Diet and capture of Hypostomus strigaticeps (Siluriformes, Loricariidae) in a small brazilian stream: relationship with limnological aspects

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