Patterns of Co-occurrence of Rare and Threatened Species in Winter Arable Plant Communities of Italy

Detecting patterns of species co-occurrence is among the main tasks of plant community ecology. Arable plant communities are important elements of agroecosystems, because they support plant and animal biodiversity and provide ecosystem services. These plant communities are shaped by both agricultural and environmental drivers. The pressure of intensive agriculture worldwide has caused the decline of many characteristic arable species and communities. Italy is the European country where arable plant biodiversity is the best preserved. In this study, we assessed the patterns of co-occurrence of rare and threatened arable plants in 106 plots of winter arable vegetation located from Piedmont to Calabria, in the mainland part of the country. For this purpose, we based our investigation on the analysis of a recently acquired dataset and on the European list of rare and threatened arable plants. We highlight how different species of conservation interest tend to occur in the same community. On the other hand, generalist and more competitive taxa show similar patterns of co-occurrence. We suggest that single species of conservation value could be suitable indicators of a well-preserved community. On the other hand, to be effective, conservation strategies should target the whole community, rather than single species.

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The stuble-field plant communities in South-East Poland. Part V. The comparative characteristics of stuble-fleld plant communities

Acta Agrobotanica ◽

10.5586/aa.1993.009 ◽

2013 ◽

Vol 46 (1) ◽

pp. 99-127

Author(s):

Czesława Trąba

Keyword(s):

Plant Communities ◽

The Other ◽

Euphorbia Esula ◽

Soil Conditions ◽

Hydrological Conditions ◽

Mechanical Structure ◽

Field Plant ◽

Other Hand ◽

Setaria Glauca

In this of the presented paper results of the studies conducted in preceding four parts (I-IV) were synthetically assumed. On that background a comparative characteristics of specified stuble-field plant communities was conducted. It contains the most important features of communities and seats, in which they appear. In climatically, geomorphologically, hydrologically and with respect to soils differentiated conditions of South-East Poland, especially in former Rzeszów region, there were described stubble-field plant communities occurring as well on lowland, as on highland agricultural utility complexes. There were analysed 359 phytosociological records, in which 232 ones came from lowland, while 127 from highland complexes. The specified communities were included to two orders: Secali-Violetalia arvensis (suborder Polygono-Chenopodienalia : alliances Eu-Polygono-Chenopodion and Panico-Setarion) and Cyperetalia fusci (alliance Nanocyperion flavescentis). On the lowland agricultural utility complexes specified were seven types of communities: 3 belonged to Panico-Setarion alliance (association Digitarietum ischaemi; community with Setaria glauca and association Echinochloo-Setarietum), 2 to Eu-Polygono-Chenopodion alliance (the community with Euphorbia esula and Oxalis stricta as well the community with Veronica persica), while 2 associations from the Nanocyperion flavescentis (Hyperico-Spergularietum and Centunculo-Anthocerotetum) alliance. On the other hand, on the highland complexes of South-East Poland only 3 communities were found: 1) with Setaria glauca included to Panico-Setarion alliance, 2) with Veronica persica from Eu-Polygono-Chenopodion alliance and 3) Centunculo-Anthocerotetum association from Nanocyperion flavescentis alliance. The specified floral types, as well as lower units (variants and sub variants), reflected the mechanical structure, hydrological conditions and pH soils in their seats, what confrumed a great differentiation of soil conditions on the tested area.

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Botanical geography correspondence between Alexander von Humboldt and Filippo Parlatore (1851-1852)

Natural History Sciences ◽

10.4081/nhs.2020.470 ◽

2020 ◽

Vol 7 (2) ◽

Author(s):

Enrico Banfi ◽

Agnese Visconti

Keyword(s):

Plant Communities ◽

The Other ◽

Natural Plant ◽

Alexander Von Humboldt ◽

Other Hand ◽

State Library ◽

The One ◽

The Relationship ◽

Selection Of

This paper focuses on the relationship between Alexander von Humboldt, the famous German explorer-naturalist and Filippo Parlatore, botanist from Palermo (Sicily, Italy) in the field of botanical geography. Our considerations are based on three letters written by Humboldt to Parlatore in May 1851 and two letters with attachments written by Parlatore in answer to Humboldt in May 1851 and June 1852. The former are preserved in the Biblioteca comunale di Palermo (Palermo City Library) and the latter in the Staatsbibliothek zu Berlin (Berlin State Library). On reading the correspondence it can be inferred how, on the one hand, Humboldt asked Parlatore for verification on some important questions of botanical geography that he intended to cover in the second part (never published) of volume five of his Kosmos, and how, on the other hand, Parlatore diverged in his answers from Humboldt’s intent to search for universal laws to explain the distribution of plants on the planet. In fact, Parlatore was engaging in new lines of research, which, though stemming from Humboldt, were moving towards a modern twodimensional interpretation of natural plant communities according to which vegetation and flora, though interacting, are distinct realities and require different methods of study. The paper includes a portrait of Parlatore and one of Humboldt, a taxonomic table of the plants mentioned by the two scientists in their correspondence and illustrations of a selection of the same plants.

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A study of cometary eruptions through OH radio-lines

International Astronomical Union Colloquium ◽

10.1017/s025292110003150x ◽

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.

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Closing the GAP—A 5Å Scanning Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061938 ◽

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.

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Life Beyond 1MeV

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600000118 ◽

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.

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Can the Academic Self-Concept be Positive and Realistic?

Zeitschrift für Pädagogische Psychologie ◽

10.1024/1010-0652.19.3.132 ◽

2005 ◽

Vol 19 (3) ◽

pp. 129-132 ◽

Cited By ~ 6

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.

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Stories and the Self

Journal of Media Psychology Theories Methods and Applications ◽

10.1027/1864-1105/a000255 ◽

2020 ◽

Vol 32 (2) ◽

pp. 47-58 ◽

Cited By ~ 1

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.

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Don’t Put Me in This Group

Social Psychology ◽

10.1027/1864-9335/a000363 ◽

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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