scholarly journals Soil invertebrates in southern Brazilian Araucaria forest - grassland mosaic: differences between disturbed and undisturbed areas

2009 ◽  
Vol 99 (3) ◽  
pp. 307-312 ◽  
Author(s):  
André Frainer ◽  
Marcelo M. Duarte
Keyword(s):  
Soil Invertebrates ◽  
The Other ◽  
Soil Invertebrate ◽  
Southern Brazil ◽  
Araucaria Forest ◽  
Taxonomic Level ◽  
Other Hand ◽  
Disturbed Area ◽  
Forest Habitats

Soil invertebrate distribution in Araucaria forest, grassland and edge habitats was studied in both disturbed and undisturbed areas in southern Brazil. Mean-density and taxa compositions were verified. Invertebrate densities differed between grassland and the other two habitats in the undisturbed area but not across the disturbed one. At the disturbed area taxa differed between the grassland and the other two habitats. The undisturbed area, on the other hand, presented taxa differences only between the grassland and the forest habitats. Acari, Arachnida and Collembola were the most sensitive taxa for detecting differences across habitats in both areas. At the disturbed area, these taxa presented densities lowering from the forest to the grassland. At the undisturbed area the same taxa increased from the forest to the grassland. Coleoptera and Formicidae (Insecta) presented no difference between habitats at the studied taxonomic level.

scholarly journals Ecology and Diversity of Urban Pine Forest Soil Invertebrates in Rīga, Latvia / Augsnes Bezmugurkaulnieku Bioloģiskā Daudzveidība Urbānajos Priežu Mežos Rīgā, Latvijā

2015 ◽  
Vol 69 (3) ◽  
pp. 120-131
Author(s):  
Dmitry Telnov ◽  
Ineta Salmane
Keyword(s):  
Soil Fauna ◽  
Urban Forest ◽  
Soil Invertebrates ◽  
Soil Invertebrate ◽  
Community Similarity ◽  
Faunal Diversity ◽  
Undisturbed Soils ◽  
Pine Forest Soil ◽  
Disturbed Soils ◽  
Forest Habitats

Abstract A study on ecology and diversity of soil invertebrates of urban pine and mixed pine forests was carried out in seven different sampling plots in Rīga during 2014. Ninety eight soil samples were processed and in total, 40 426 specimens were extracted (of them, 25 237 specimens were identified to species level and 15 189 to order level). Indices (abundance, community similarity etc.) characterising faunal diversity and species communities of Rīga city soil fauna were estimated. The most numerous soil invertebrate groups were Collembola, Oribatida and Mesostigmata, accounting for 95% of all collected animals. There was rather high diversity of soil invertebrates in the disturbed urban forest habitats, but undisturbed soils harbour a greater species richness of mite fauna than disturbed soils.

Behaviour and daily activity of the squirrel Sciurus ingrami in a secondary araucaria forest in southern Brazil

2000 ◽  
Vol 78 (10) ◽  
pp. 1732-1739 ◽  
Author(s):  
Marcelo Bordignon ◽  
Emygdio LA Monteiro-Filho
Keyword(s):  
The Other ◽  
Southern Brazil ◽  
Mating Period ◽  
Araucaria Forest ◽  
Morning Peak ◽  
The Mean ◽  
Two Peaks ◽  
Autumn And Winter ◽  
Number Of Males ◽  
Daily Time

A study on the behaviour of a population of squirrels, the "serelepe" (Sciurus ingrami), was conducted in a secondary araucaria forest in southern Brazil. Forty-three squirrels were marked and observed between 05:00 and 18:00 daily. The largest number of males were trapped during the winter, coinciding with an increase in the number of agonistic encounters and mating chases. Two peaks in occurrence of trapped pregnant females were found, one during the winter and the other in the summer. The population density was 0.89 squirrels/ha and the mean area occupied by males was larger during the winter mating period, decreasing gradually during subsequent seasons. The diurnal activity of S. ingrami exhibited bimodal curves in all seasons, with one peak in the morning and another in the afternoon. During the winter, the morning peak was greater in amplitude than during the other seasons. In the spring and summer, a marked increase in the activity of the squirrels during the hottest hours occurred. The morning peak of activity occurred earlier in the spring and summer and later in the autumn and winter. The daily time spent inrest, displacement, feeding, and maintenance showed seasonal variation similar to that shown by other sciurids.

scholarly journals Citrus sudden death-associated virus (CSDaV) and citrus tristeza virus (CTV) in eleven rootstocks for ‘Valência’ sweet orange

2018 ◽  
Vol 40 (4) ◽  
Author(s):  
André Luiz Fadel ◽  
Francisco de Assis Alves Mourão Filho ◽  
Eduardo Sanches Stuchi ◽  
Nelson Arno Wulff ◽  
Hilton Thadeu Zarate Couto
Keyword(s):  
Sudden Death ◽  
Citrus Tristeza Virus ◽  
Sweet Orange ◽  
Disease Incidence ◽  
The Other ◽  
Southern Brazil ◽  
Rangpur Lime ◽  
Other Hand ◽  
Tristeza Virus ◽  
Citrus Tristeza

Abstract Citrus sudden death (CSD) is a highly destructive disease and has caused the eradication of millions of trees in southern Brazil within the last 15 years. In spite of the exact cause of CSD has not been determined, evidences have shown that this disease can be transmitted by biotic vectors. Disease incidence in sweet orange scions is related to the rootstock, and the combination with ‘Rangpur’ lime is the most affected. On the other hand, there are evidences of a relation between CSD affected trees and the presence of the Citrus sudden death associated virus (CSDaV) and/or Citrus tristeza virus (CTV). Based on such information, this study has been carried out to determine the presence of CSDaV and CTV, and the association between each other in eleven rootstocks for ‘Valencia’ sweet orange. The results presented herein showed differences related to the presence of CSDaV and CTV in different rootstocks for ‘Valencia’ sweet orange and no relation between the presence of CSDaV and CTV.

scholarly journals Geographical and seasonal distributions of the seedeaters Sporophila bouvreuil and Sporophila pileata (aves: Emberizidae)

2010 ◽  
Vol 50 (32) ◽  
pp. 517-533 ◽  
Author(s):  
Érika Machado ◽  
Luís Fábio Silveira
Keyword(s):  
Seed Production ◽  
Breeding Season ◽  
Atlantic Forest ◽  
Short Distance ◽  
Movement Patterns ◽  
The Other ◽  
Southern Brazil ◽  
Migration Patterns ◽  
Other Hand ◽  
Resident Populations

Many species in the genus Sporophila are migratory. Migration patterns, while poorly studied, may be influenced by seed production which can be very seasonal in some regions. The distribution of S. bouvreuil extends from the Amazon and Suriname south through a large part of the open regions of Brazil. Sporophila pileata, on the other hand, is found in southeastern and southern Brazil as well as Argentina and Paraguay. Both of these species migrate, but their movement patterns are poorly known. To better understand the geographical and the seasonal distributions of S. bouvreuil and S. pileata, we grouped the records into two categories: the breeding season (September to March) and the putative migration season (April to August). We found two areas of sympatry between S. bouvreuil and S. pileata in the Brazilian states of Minas Gerais and São Paulo. For S. bouvreuil we suggest that populations that breed in the Amazon migrate to the Cerrado or Caatinga, where they will encounter resident populations of the same species. These resident populations may take part in short distance migrations. Sporophila pileata, on the other hand, occur in the Cerrado and open areas within the Atlantic Forest and it is not yet possible to determine migratory tendencies or destinations in the non-breeding season.

A study of cometary eruptions through OH radio-lines

1999 ◽  
Vol 173 ◽  
pp. 249-254
Author(s):  
A.M. Silva ◽  
R.D. Miró
Keyword(s):  
Short Duration ◽  
Growth Curves ◽  
The Other ◽  
Initial Mass ◽  
Radio Lines ◽  
Other Hand ◽  
Sudden Rise

AbstractWe have developed a model for theH2OandOHevolution in a comet outburst, assuming that together with the gas, a distribution of icy grains is ejected. With an initial mass of icy grains of 108kg released, theH2OandOHproductions are increased up to a factor two, and the growth curves change drastically in the first two days. The model is applied to eruptions detected in theOHradio monitorings and fits well with the slow variations in the flux. On the other hand, several events of short duration appear, consisting of a sudden rise ofOHflux, followed by a sudden decay on the second day. These apparent short bursts are frequently found as precursors of a more durable eruption. We suggest that both of them are part of a unique eruption, and that the sudden decay is due to collisions that de-excite theOHmaser, when it reaches the Cometopause region located at 1.35 × 105kmfrom the nucleus.

Closing the GAP—A 5Å Scanning Microscope

1969 ◽  
Vol 27 ◽  
pp. 6-7
Author(s):  
A. V. Crewe
Keyword(s):  
Normal Form ◽  
The Other ◽  
Resolving Power ◽  
Scanning Microscope ◽  
Conventional Microscope ◽  
Other Hand ◽  
Closing The Gap ◽  
Thermal Sources ◽  
Better Than ◽  
Transmission Microscope

We have become accustomed to differentiating between the scanning microscope and the conventional transmission microscope according to the resolving power which the two instruments offer. The conventional microscope is capable of a point resolution of a few angstroms and line resolutions of periodic objects of about 1Å. On the other hand, the scanning microscope, in its normal form, is not ordinarily capable of a point resolution better than 100Å. Upon examining reasons for the 100Å limitation, it becomes clear that this is based more on tradition than reason, and in particular, it is a condition imposed upon the microscope by adherence to thermal sources of electrons.

Life Beyond 1MeV

1980 ◽  
Vol 38 ◽  
pp. 30-33
Author(s):  
K.H. Westmacott
Keyword(s):  
Electron Microscopy ◽  
Past Experience ◽  
The Other ◽  
Good Case ◽  
Other Hand ◽  
The U.S

Life beyond 1MeV – like life after 40 – is not too different unless one takes advantage of past experience and is receptive to new opportunities. At first glance, the returns on performing electron microscopy at voltages greater than 1MeV diminish rather rapidly as the curves which describe the well-known advantages of HVEM often tend towards saturation. However, in a country with a significant HVEM capability, a good case can be made for investing in instruments with a range of maximum accelerating voltages. In this regard, the 1.5MeV KRATOS HVEM being installed in Berkeley will complement the other 650KeV, 1MeV, and 1.2MeV instruments currently operating in the U.S. One other consideration suggests that 1.5MeV is an optimum voltage machine – Its additional advantages may be purchased for not much more than a 1MeV instrument. On the other hand, the 3MeV HVEM's which seem to be operated at 2MeV maximum, are much more expensive.

Can the Academic Self-Concept be Positive and Realistic?

2005 ◽  
Vol 19 (3) ◽  
pp. 129-132 ◽  
Author(s):  
Reimer Kornmann
Keyword(s):  
Academic Performance ◽  
Opposite Effect ◽  
Self Esteem ◽  
Point Of View ◽  
The Other ◽  
Self Concept ◽  
High Ability ◽  
Self Image ◽  
Other Hand

Summary: My comment is basically restricted to the situation in which less-able students find themselves and refers only to literature in German. From this point of view I am basically able to confirm Marsh's results. It must, however, be said that with less-able pupils the opposite effect can be found: Levels of self-esteem in these pupils are raised, at least temporarily, by separate instruction, academic performance however drops; combined instruction, on the other hand, leads to improved academic performance, while levels of self-esteem drop. Apparently, the positive self-image of less-able pupils who receive separate instruction does not bring about the potential enhancement of academic performance one might expect from high-ability pupils receiving separate instruction. To resolve the dilemma, it is proposed that individual progress in learning be accentuated, and that comparisons with others be dispensed with. This fosters a self-image that can in equal measure be realistic and optimistic.

Stories and the Self

2020 ◽  
Vol 32 (2) ◽  
pp. 47-58 ◽  
Author(s):  
Stefan Krause ◽  
Markus Appel
Keyword(s):  
Meta Analysis ◽  
The Self ◽  
The Other ◽  
Lower Degree ◽  
Contrast Effects ◽  
Self Perception ◽  
Self Perceptions ◽  
Other Hand ◽  
The One ◽  
Implicit And Explicit

Abstract. Two experiments examined the influence of stories on recipients’ self-perceptions. Extending prior theory and research, our focus was on assimilation effects (i.e., changes in self-perception in line with a protagonist’s traits) as well as on contrast effects (i.e., changes in self-perception in contrast to a protagonist’s traits). In Experiment 1 ( N = 113), implicit and explicit conscientiousness were assessed after participants read a story about either a diligent or a negligent student. Moderation analyses showed that highly transported participants and participants with lower counterarguing scores assimilate the depicted traits of a story protagonist, as indicated by explicit, self-reported conscientiousness ratings. Participants, who were more critical toward a story (i.e., higher counterarguing) and with a lower degree of transportation, showed contrast effects. In Experiment 2 ( N = 103), we manipulated transportation and counterarguing, but we could not identify an effect on participants’ self-ascribed level of conscientiousness. A mini meta-analysis across both experiments revealed significant positive overall associations between transportation and counterarguing on the one hand and story-consistent self-reported conscientiousness on the other hand.

Don’t Put Me in This Group

2019 ◽  
Vol 50 (2) ◽  
pp. 80-93
Author(s):  
Jort de Vreeze ◽  
Christina Matschke
Keyword(s):  
Positive Emotions ◽  
Negative Emotions ◽  
Negative Information ◽  
The Self ◽  
The Other ◽  
Other Hand ◽  
Group Memberships

Abstract. Not all group memberships are self-chosen. The current research examines whether assignments to non-preferred groups influence our relationship with the group and our preference for information about the ingroup. It was expected and found that, when people are assigned to non-preferred groups, they perceive the group as different to the self, experience negative emotions about the assignment and in turn disidentify with the group. On the other hand, when people are assigned to preferred groups, they perceive the group as similar to the self, experience positive emotions about the assignment and in turn identify with the group. Finally, disidentification increases a preference for negative information about the ingroup.

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