Search results for "Temperate climate"
showing 10 items of 109 documents
Life-history of two African Sylvia warblers: low annual fecundity and long post-fledging care
2004
The investigation of factors that cause differences in life-history traits between temperate and tropical birds is often hampered by a lack of knowledge about tropical species. Even within the well-known warblers of the genus Sylvia, which include resident species from temperate and tropical regions as well as migrants, there are few data from tropical species. We investigated the breeding biology of the tropical species Sylvia lugens and S. boehmi in a 2-year study in Kenya. Both species had a clutch size of 2.0 and laid c. 3.7 clutches per year. Breeding was characterized by long incubation periods (S. lugens 14.5 days, S. boehmi 15.0 days), long nestling periods (16.0 and 12.9 days, resp…
Olfactory foraging in temperate waters: sensitivity to dimethylsulphide of shearwaters in the Atlantic Ocean and Mediterranean Sea
2014
AbstractMany procellariiforms use olfactory cues to locate food patches over the seemingly featureless ocean surface. In particular, some of them are able to detect and are attracted by dimethylsulfide (DMS), a volatile compound naturally occurring over worldwide oceans in correspondence with productive feeding areas. However, current knowledge is restricted to sub-Antarctic species, and to only one study realized under natural conditions at sea. Here, for the first time, we investigated the response to DMS in parallel in two different environments in temperate waters, the Atlantic Ocean and the Mediterranean Sea, employing Cory's (Calonectris borealis) and Scopoli's shearwaters (Calonectri…
Synopsis of Carex (Cyperaceae) from sub-Saharan Africa and Madagascar
2011
This synopsis provides a key, synonymy, lectotypification, habitat descriptions and distributions for the 81 species and six additional infraspecific taxa of Carex known from tropical and southern Africa and Madagascar. It is the first treatment of Carex including all tropical and southern temperate areas in Africa since Kukenthal's monograph of subfamily Caricoideae in 1909. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 166, 51–99.
Environmental and Biochemical Factors Controlling the in Vitro Emergence of Somatic Embryos in European Spindle Tree (Euonymus europaeus L)
2000
The European spindle tree (Euonymus europaeus L. Celastraceae) is a shrubby tree widely distributed in temperate regions of western European countries from the northern part of France to St. Petersburg and the western part of Russia. The Celastraceae comprises 55 genera, including at least 850 known species of trees and shrubs which are found in tropical and temperate regions. Various secondary metabolites are elaborated in the family including steroids, triterpenoids, sesquiterpene, peptide ore alkaloids. The spindle tree is commonly found in quickset hedges and small broad-leaved forests when the soil is deep, moist, clayey and chalky. The leaves are relatively small (3–4 cm long) simple …
The effect of clove oil sedation on oxygen consumption of six temperate-zone fish species
2004
Yield development of flax varieties and lines within variable environment in Latvia
2015
Flax is the multiple purpose crop cultivated in temperate region. Seeds of oil flax recently became important constituent for many industrial applications, such as pharmacy, medicine, food production <em>etc.</em> and have high prospective for use in Latvia. Understanding the underlying processes that limit seed yield in flax is major with respect to enhancing the breeding of flax for yield improvements. The aim of study was evaluated 29 flax varieties and lines (including 20 Latvian origins) plasticity of seed yield production in changeable environmental conditions. The experiment was carried out in the Agricultural Scientific Centre of Latgale on field trials over the period 2…
Biology of the preimaginal stages in trogid beetles (Coleoptera): Experimental data∗
1992
Abstract Some aspects of larval behaviour in two species of trogid beetles, Trox bispidus (Pontoppidan) from temperate Europe and Afromorgus tuberosus (Klug) from tropical Africa, have been studied experimentally. From the results obtained it emerges that the rise of the newborn larvae towards the soil surface is imputable to a simple negative geotropism. Larval food relocation also contributes to reducing aggressive interactions at the food source. The potential range of trophic and behavioural variation seems to be larger than that expressed in nature as a rule. This can contribute to explaining, in evolutive terms, the rare cases of transgression from a uniform trophic and behavioural pa…
The Effect of perturbations on phytoplankton assemblages in a deep reservoir (Vouglans, France)
2003
Disturbances, such as rainfall and hydrological management of Vouglans reservoir, seem to influence the establishment of the ecological system inside this man-made lake. In this paper, the main effect of these disturbances are changes in the z mix :z eu ratio, with a shift in the composition and phytoplankton dynamics, and consequently in the Shannon’s diversity. The seasonal changes found in the surface layers of Vouglans reservoir were typical for mesotrophic and temperate lakes, but some perturbations induced the ‘reversion’ to an earlier stage in the expected successional pattern during the stratification period. This early-state displayed an intensive proliferation of the filamentous u…
Factors affecting the distribution of recent lacustrine ostracoda from the Caicedo de Yuso-Arreo Lake (Western Ebro Basin, Spain)
2005
Recent Ostracoda assemblages of the Caicedo de Yuso Lake have been described as representative of palustrine/lacustrine environments in Iberian temperate lakes. This study considers the changes in assemblages at a fixed station during two consecutive annual cycles, as well as their distribution in summer and winter profiles of the lake. Total sample-assemblages have been quantified as species diversities, measured by the Shannon-Wiener index H (S). The trends of this index are compared to physical parameters (temperature, conductivity, dissolved oxygen, CO2) of the bottom waters of this lake. The Ostracoda assemblages (8100 adults and juvenile living specimens, belonging to 20 species) are …
Shape and size in phytoplankton ecology: do they matter?
2007
This paper summarises the outcomes of the 14th Workshop of the International Association of Phytoplankton Taxonomy and Ecology (IAP). The authors mostly addressed their contributions on the following topics: morphological and morpho-functional descriptors of phytoplankton, size and shape structure of phytoplankton related to different kinds of environmental variables and the role of morphological and physiological plasticity of phytoplankton in maintaining the (apparently) same populations under different environmental conditions. Case studies from different kinds of aquatic environments (deep and shallow lakes, reservoirs with different age, purpose and trophic state, floodplain wetlands m…