Search results for "ecological succession"
showing 10 items of 96 documents
40 Ar/ 39 Ar ages of fallout tephra layers and volcaniclastic deposits in the sedimentary succession of the western Woodlark Basin, Papua New Guinea:…
2001
Late Pliocene and Pleistocene small mammal chronology in the Italian peninsula
2007
The abundant documentation of small mammals in the Italian peninsula, collected over recent years, furnishes a detailed biochronological sequence mainly from the Late Pliocene onwards. An updated stratigraphic framework is here presented, based on the European small mammal biozonation. The Early Villanyian is characterized by Mimomys hassiacus, M. stehlini, and, later, poorly documented M. polonicus. The Late Villanyian localities are well characterized with M. pliocaenicus, M. pitymyoides and M. tigliensis. The older part of the Early Biharian is documented by assemblages containing Microtus (Allophaiomys) ex gr. pliocaenicus, M. pusillus, M. cf. ostramosensis and M. tornensis, while the l…
Impact of secondary succession in abandoned fields on some properties of acidic sandy soils
2020
Abstract Abandonment of agricultural lands in recent decades is occurring mainly in Europe, North America and Oceania, and changing the fate of landscapes as the ecosystem recovers during fallow stage. The objective of this study was to find the impact of secondary succession in abandoned fields on some parameters of acidic sandy soils in the Borská nížina lowland (southwestern Slovakia). We investigated soil chemical (pH and soil organic carbon content), hydrophysical (water sorptivity, and hydraulic conductivity), and water repellency (water drop penetration time, water repellency cessation time, repellency index, and modified repellency index) parameters, as well as the ethanol sorptivit…
The “Start-up a Business” Strategy in the Succession Process Planning at the Top of Family Firms.
2019
In small family firms, succession to the top is very critical stage of their lives. A high percentage of these firms do not survive their founder. When the successor takes the reins of the company, he has no experience and reputation. For this reason, he very often fails to allow the family firm to survive after its founder. Although many streams of research address succession in family businesses, significant gaps in the literature remain in the field of the strategies that can mitigate the vulnerability of the family firms when the old leader retires and a new leader takes the reins of the company. The underlying argument in this paper is: By starting up one’s own company some years befor…
Impact of wheat straw decomposition on successional patterns of soil microbial community structure
2009
International audience; The dynamics of indigenous bacterial and fungal soil communities were followed throughout the decomposition of wheat straw residue. More precisely, such dynamics were investigated in the different soil zones under the influence of decomposing wheat straw residue (i.e. residues, soil adjacent to residue = detritusphere, and bulk soil). The genetic structures of bacterial and fungal communities were compared throughout the decomposition process long by applying B- and F-ARISA (for bacterial and fungal-automated ribosomal intergenic spacer analysis) to DNA extracts from these different zones. Residue decomposition induced significant changes in bacterial and fungal comm…
Soil carbon dynamics during secondary succession in a semi-arid Mediterranean environment
2018
Clarifying which factors cause an increase or decrease in soil organic carbon (SOC) after agricultural abandonment requires integration of data on the temporal dynamics of the plant community and SOC. A chronosequence of abandoned vineyards was studied on a volcanic island (Pantelleria, Italy). Vegetation in the abandoned fields was initially dominated by annual and perennial herbs, then by Hyparrhenia hirta (L.) Stapf, and finally by woody communities. As a consequence, the dominant photosynthetic pathway changed from C3 to C4 and then back to C3. Conversion of a plant community dominated by one photosynthetic pathway to another changes the 13C/12C ratio of inputs to soil organic carbon (S…
Middle Eocene calcareous nannofossils in the Jaca transect (South-central Pyrenees Eocene Basin, Aragón river valley, Huesca)
2020
The calcareous nanoplankton is studied from the base of the turbidite systems of the Upper Hecho Group (Jaca Basin, middle Eocene of the South-central Pyrenean Basin) up to the Gracionepel instabilities, within the Larres slope Marls. This new chronostratigraphic contribution is of crucial importance for the improvement of the detailed temporal and spatial correlation framework of the genetically related depositional systems at basin scale. The calcareous nanofossil assemblage is largely dominated by Coccolithus pelagicus , C. formous as well as different species of Reticulofenestra , accompanied by occasional specimens of several species of Sphenolithus and Chiasmolithus . The results obt…
Succession et remplacements de communautés à brachiopodes en régime de sédimentation discontinue (Jurassique Moyen, Bourgogne, France)
1993
Abstract Sequence stratigraphy throws a new and seminal light on the fossil record and helps in determining the respective role played by external control (community replacement) and internal control (paleoecological succession) in the temporal “train” of marine benthic paleocommunities. Five brachiopod-dominated communities (C1–C5) are recognized and their temporal “train” described, during the uppermost Bathonian-lower Callovian interval in Burgundy. The first series (C1–C3) exhibits a trend interpreted as a paleoecological succession and the next two (C3–C4, C4–C5) as community replacements. Within the scope of sequence stratigraphy, the paleoecological succession comes at the end of a t…
State Continuity, Succession and Responsibility: Reparations to the Baltic States and their Peoples?
2003
Experience discrepancy in leadership succession: Does it matter? Evidence from the Elite European Soccer Clubs (1994-2015)
2018
International audience; The level of profile similarity between the new leader and the former one matters and will affect subsequent strategic change and thus performance. An excess of exploration as well as an excess of exploitation are detrimental to future performance. When replacing a leader, owners should take into consideration the profile and experience dissimilarities between the predecessor and the successor.